Tracking pedogenic carbonate formation and migration in agricultural soils amended with crushed wollastonite ore- Evidence from field trials

Tracking pedogenic carbonate formation and migration in agricultural soils amended with crushed wollastonite ore- Evidence from field trials | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Tracking pedogenic carbonate formation and migration in agricultural soils amended with crushed wollastonite ore- Evidence from field trials Reza Khalidy, Yi Wai Chiang, Rafael M. Santos This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3851689/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Considered as a well-known carbon sequestration method, terrestrial enhanced rock weathering involves the application of crushed silicate-bearing minerals to urban and agricultural soils. Once dissolved in the soil-water system, alkaline minerals adjust the pH in a range favorable for pedogenic carbonate formation and, hence, atmospheric carbon drawdown. As a fast-weathering Ca-rich mineral, wollastonite is recognized as one of the primary candidates for this process. Although previous studies proved the potential of wollastonite to sequester carbon in croplands, no study has investigated the fate of wollastonite over the vertical profile of soil. Furthermore, no studies have investigated changes in the elemental composition of soils due to wollastonite amendment on a field scale. The present study presents the results of a multi-year sampling collection from different layers (0–15, 15–30, and 30–60 cm) of agricultural soil amended with wollastonite in Woodstock, Ontario, Canada. The impact of initial soil pH on pedogenic carbonate formation was also investigated with the inclusion of two more field trials. The results denoted wollastonite addition increases the inorganic carbon pool of soil up to 6.60 t CO 2 /ha at higher (20 t/ha) wollastonite dosage. The elemental composition and mineralogy analyses were indicative of weathering occurrence in soil samples. This study indicates that carbonate formation is not limited to surficial layers, and deeper layers also need to be taken into account for estimating carbon capture due to ERW practice. Environmental Engineering Agronomy Geochemistry enhanced rock weathering soil inorganic carbon pedogenic carbonate formation carbon dioxide removal Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 1. Introduction Induced from anthropogenic activities, fossil fuels emissions are the prime mover of atmospheric CO 2 concentration to 100 ppm above the pre-industrial range and global warming and climate change-related ramifications (Khalidy and Santos, 2021a ; Millar et al., 2017 ; Lindsey and Dahlman, 2020 ). As an urgent response, drawing up and scaling up carbon dioxide removal (CDR) technologies are needed to decelerate this trend (Kelemen et al., 2020 ; Khalidy and Santos, 2021b ; Rahmanihanzaki and Hemmati, 2022 ). Among CDR technologies, mineral carbonation is being recognized as a long-term carbon storage sink using feedstocks that occur naturally in Earth terrestrial ecosystems (Oelkers et al., 2008; Wilson et al., 2014 ). As the third largest pool of carbon in the world, soil is deemed as an earth-shattering sink for carbon (Stanbery et al., 2023 ; Zamanian et al., 2016 ). Carbon storage might be accumulated in the forms of soil organic carbon (SOC) or soil inorganic carbon (SIC) in soil (Beerling et al., 2018 ; Lal 2007 ; Sanderman 2012). The carbon sequestration as SOC, highly dependent on practice management (Sanderman 2012) and subjected to decarbonization (Jorat et al., 2022 ), is usually regulated through photosynthesis and the organic matter cycle (Haque et al. 2019b ). SIC, on the other hand, is recognized as a stable pool, and its sequestration proceeds through weathering of alkaline metals (Haque et al. 2019a ). As an endorsement of this method, the application of powdered silicate minerals (such as wollastonite, basalt, and dolerite) and crushed concrete is well acknowledged as the low-cost and low-energy method for uptaking carbon as SIC (Haque et al., 2019b ; Kelland et al., 2020 ; Manning et al., 2013 ; Renforth et al., 2015 ). This process, called enhanced rock weathering (ERW), gets underway as Ca and Mg cations become available in the soil-water system as silicate minerals dissolve (Andrews and Taylor, 2019 ). Meanwhile, the dissolution of CO 2 , originating from the atmosphere or soil organic matter (SOM), in percolating water contributes to the formation of carbonic acid and promotes the release of Ca and Mg from silicate minerals (through bringing down pH) (Beerling et al., 2018 ). The formed carbonic acid eventually dissociates to bicarbonate and proton in the soil-water solution. Depending on the geochemistry of native soil, these practices conclude either in pedogenic carbonate formation in soil/subsoil profile or migration of bicarbonates into groundwater systems (Khalidy et al., 2022 , Hartmann et al., 2013 ). Jorat et al. ( 2022 ) estimated annual carbon sequestration of 33 and 17 t/ha as pedogenic carbonate due to crushed concrete and dolerite addition in urban soils, respectively. In the study conducted by Haque et al. ( 2020a ), it was revealed both the weathering interval and dosage of Ca-rich silicate mineral (wollastonite) dosage have a positive correlation with the SIC accumulation rate (up to 6 t/ha after three years) in the agricultural fields of southwestern Ontario, Canada. From an agronomy viewpoint, the co-benefits of ERW practice on plant growth (and vice versa) are well documented (Haque et al., 2019b ; Haque et al., 2020b ; Jariwala et al., 2022 ; Kelland et al., 2020 ). The secretion of organic acids such as citric acid and maleic acid from plant roots boosts silicate minerals' dissolution and ameliorates the ERW process (Haque et al., 2019b ). Furthermore, Haque et al. ( 2020a ) demonstrated that increases of wollastonite application rates up to 10 and 5 kg/m 2 increase root biomass of alfalfa and soybean, respectively; however, higher dosages had a reverse effect on these plants. In another study, Jariwala et al. ( 2022 ) reported consistent outcomes where wollastonite treatment supplied more available Si for plants in soil. As a conventional agricultural practice, liming aims to adjust the pH of acidic soil to a neutral zone through the addition of Ca-rich materials such as lime (CaCO 3 ) and dolomite (MgCa(CO 3 ) 2 ) (Sanderman 2012). The liming process improves plant productivity (through ameliorating nutrient availability and abiotic activities) and soil aggregation (Ameyu, 2019 ; Fereira et al., 2019; Holland et al., 2017 ; Pang et al., 2019 ). However, an imminent drawback of liming is emitting CO 2 into the atmosphere that can exceed 200 Mt C per year annually and is regarded as the second practice with the highest CO 2 flux just after soil acidification (Ahmad et al., 2015 ; Sanderman, 2012; Zamanian et al., 2021 ). Therefore, ERW is alluded to as a substitution for liming, delivering coequal benefits to the agricultural and agronomy system, while turning over the carbon efflux into stabilizing carbon in soil and contributing to climate change mitigation. The procedure involving amending agricultural soil with wollastonite (e.g., determining the amount of wollastonite to apply per hectare and the method to spread it over the soil) was described by Haque et al. ( 2020a ). However, the analysis of this study was limited to a very surficial layer of soil (0–15 cm). Since weathering products (especially the finer fraction) are exposed to downward migration, we aimed to investigate the impact of the wollastonite amendment on the deeper horizons of three new agricultural fields in Southwestern Ontario. Two of these field trials were part of a lime replacement project, where the objective was to see how wollastonite ameliorates soil properties (particularly pH). For sampling soil samples in field locations, we followed a protocol that describes, in detail: (1) a soil sampling method to be used following soil silicate amendment, which accounts for the statistical significance of the analyzed soil data; (2) a soil fractionation method that improves the accuracy of quantifying changes in pedogenic inorganic carbonate pool as a result of enhanced silicate weathering, and (3) the calculation steps used to determine the SIC sequestration rate as a result of soil silicate amendment. 2. Methods 2.1 Site Description This study involves three field trial studies. The first experiment was conducted on an agricultural micro plot (soil type: Sandy loam, N 43˚14’ W 80˚62’, surface area: 0.012 acres) harvested with rye in Woodstock, Ontario (ON) (Fig. 1). The objective of this field work was to monitor pedogenic carbonate formation over the vertical profile of soil (e.g., 0–60 cm). A dosage of 15 t/ha of wollastonite was applied to the area in the Summer 2019. The soil samples were collected at different depths on a yearly basis to track changes in the pedogenic carbonate pool in soil. The first and second sample collections were concluded in Fall 2020 and Fall 2021, respectively. The objective of two other field trials was to investigate wollastonite's impact on plants’ growth and soil health (liming replacement). One of the fields, located in Dawn Euphemia, ON (soil type: Silt clay, N 42°42’ W 82°03’) (Fig. 2.a), was harvested with soybean, wheat, and corn in 2021, 2022 and 2023, respectively. The wollastonite with the rate of 10 t/ha was applied to this field in late Spring 2021. This field is 145 acres and characterized by three discrete zones of low pH, neutral pH (strip area), and high pH areas. The sampling (after wollastonite application) from this field was conducted in late April 2022. The other field is located in Thorndale, ON (soil type: Silt loam, N 43°07’ W 81°10’) (Fig. 2.b) and is harvested with a three-crop rotation (wheat, corn, and soybean) system. The wollastonite with an application rate of around 20 t/ha was applied to this field (50 acres) in late Spring 2021. The first phase of sampling from this field was conducted in October 2021. The core soils were collected from this field (before wollastonite application as “year 0” data) to investigate the impact of enhanced weathering on SIC content, pH, and physical characterization of soil. 2.2 Wollastonite Characterization The wollastonite used for field trials was sourced from Canadian Wollastonite Inc. (Canada), mined near Kingston, ON. The main characterization of the wollastonite ore from this source is demonstrated in Table 1. Table 1 . Characterization (BET, particle size distribution, and elemental composition) of wollastonite sourced from Canadian Wollastonite. BET surface area (m 2 /g) 0.198 ± 0.01 Particle size (volume %): > 500 µm 11.05 250–500 µm 47.21 63–250 µm 35.55 32–63 µm 2.18 < 32 µm 3.17 XRF(mass %) Na 2 O 2.63 MgO 6.03 Al 2 O 3 5.29 SiO 2 56.62 P 2 O 5 0.07 SO 3 0.41 Cl 0.12 K 2 O 1.32 CaO 23.97 TiO 2 0.24 V 2 O 5 0.04 Cr 2 O 3 0.02 MnO 0.06 Fe 2 O 3 2.04 SrO 0.17 LOI 0.88 According to the elemental composition of the wollastonite (Table 1), the mineral contains Mg, which could be indicative of diopside (MgCaSi 2 O 6 ), have been found to co-exist with wollastonite. This can be corroborated by looking into XRD pattern of the sample, where peaks of diopside are conspicuous along with those belonging to wollastonite. (Fig. 3). 2.4. Sample collection and soil analyses In the Woodstock field (Fig. 1), the samples were collected from three layers of 0–15, 15–30 and 30–60 cm layers of soil one year and two years after wollastonite application. Samples were collected from surficial layer (0–15) cm layer of two other fields (Thorndale and Dawn Euphemia, Fig. 2), before and after wollastonite application. The method for collecting, preparing and analyzing soil carbonate content is described in detail in our previous study (Khalidy et al., 2021 ). Accordingly, after transporting to lab, samples were air-dried. The soil samples' carbonate content (soil inorganic carbon (SIC) in gCO 2 ·(kg·soil) −1 ) was determined using the calcimetry technique. This method involved adding 20 ml of MiliQ water to the soil samples in an Erlenmeyer flask followed by the addition of 7 ml of 4 M HCL (Khalidy et al. 2021 ; Khalidy et al., 2023 ). To obtain the pan fraction (particles finer than 710 µm), soil samples were placed in oven at 105˚ C overnight. Then they were placed on a sieve shaker consisting of different mesh sizes (710 to 50 µm), at 60 rpm for 15 min. Finally, the carbonate content of pan fraction was compared with the bulk samples. To determine the pH of soil samples, 5:1 volumetric ratio of water was added to the soil, and the formed suspension was placed for 1 hour on a shaker (Rayment and Higginson, 1992 ). Then, the suspension was kept motionless for another hour before measurement using a pH meter (Oakton pH 700 Benchtop meter). To account for the changes in the mineral phases of soil samples due to wollastonite treatment, X-ray diffraction (XRD, Panalytical Empyrean) and X-ray fluorescence (XRF, Rigaku Supermini 200) analyses were employed. The multipoint Brunauer-Emmett-Teller (BET) surface area and particle size distribution of wollastonite were determined using a physisorption analyzer (Quantachrome Autosorb iQ) and laser diffraction (Malvern Mastersize SM), respectively. 2.5. Data Analyses All readings of experimental analyses on soil and leachate samples were conducted in triplicate, and the mean of results was reported (along with standard error). To discern the statistical significance of treatments (control vs. wollastonite amendment), the Independent Samples T-Test was used in IBM SPSS software. 3. Results and Discussion 3.1 Mineralogy and elemental composition Figure 4 demonstrates the XRD diffractograms of soils amended with wollastonite and the corresponding control soils. Due to the complexity of soil composition, quantifying the mineral phases is challenging (Haque et al., 2020a ); therefore, the peaks were identified qualitatively. According to Fig. 4, Quartz and Albite are present in samples from all locations, while there are minor differences in the other phases. Regarding minor phases, microcline is present in all locations, while muscovite was only detected in Woodstock and Dawn Euphemia soils. When it comes to weathering products, minuscule peaks of calcite are detectable in the amended samples. Several wollastonite and diopside peaks are visible in Thorndale field’s soil, while are absent in other fields. Comparing the XRD results of field soil and our soil column experiment (discussed in Chap. 5), it can be deduced that wollastonite/diopside phases are much more distinct in the latter. This can be explained in two ways. First, a higher wollastonite dosage was applied in the column experiment (50 t/ha vs. 5–20 t/ha in the field trials), so it is more probable that a higher amount of unweathered portion remains in the soil for a longer time. Interestingly, the only occurrence of wollastonite peaks in field samples corresponds to the highest dosage of wollastonite application (Thorndale location, 20 t/ha) among field trials. Furthermore, field trials took longer (6 months to 1 year) than column experiment (5 months), which left more time for wollastonite to weather in soil. As discussed by Calabrese et al. ( 2022 ), ambient factors such as climate and abiotic agents could boost mineral dissolution in the field scale compared to laboratory condition. XRF analyses denote an increment of CaO% in all samples, while MgO% follows the same trend except for Dawn Euphemia (DE) field (high pH area), showing a slight decrease (Fig. 5). The highest amendment occurred in the Woodstock field (0.7 and 0.5% increase in the CaO and MgO contents, respectively). Looking at some other elements (Al 2 O 3 ,Fe 2 O 3 and SiO 2 ) there is no clear trend after the wollastonite introduction. For example, the content of SiO 2 shows two different trends of increase (DE, Neutral Area and Thorndale Field) and decrease (Woodstock, DE Low pH and High pH areas). 3.2 Carbonate content The carbonate content of field soils before and after wollastonite application are illustrated in Fig. 6. The SIC in Woodstock, Thorndale and Neutral area of Dawn Euphemia are 2.52, 1.71 and 2.46 (gr, CaCO 3 (eqv)/(kg,soil)), respectively (in Woodstock field, no soil collection was conducted before application and soil obtained from neighborhood field is regarded as “before application). The carbonate accumulation in Woodstock and Thorndale fields is notable, corresponding to more than 4 and 6 times higher compared to prior application contents, respectively. In the Dawn Euphemia field, the SIC of field soils before wollastonite application has a negative correlation with initial pH and is in the range of 0.62 (in the Low pH area of the Dawn Euphemia field) and 4.76 (in the High pH area of Dawn Euphemia) (g, CaCO3 (eqv)/(kg,soil)). Although the accumulation of carbonates in this field is lower than in the other fields, the trend of increment is in agreement with local SIC and pH of soil. Accordingly, the net carbonate accumulation in Low pH, Neutral and High pH areas equals 1.93, 1.10 and 0.78 (g, CaCO 3 (eqv)/(kg,soil)), respectively. These findings imply that the lower the pH of soil, the higher the accumulation of pedogenic carbonate in the Dawn Euphemia field. However, previous studies have shown increasing pH favors pedogenic carbonate formation, while wollastonite dissolution is promoted in low pH soil (Haque et al., 2019b ). One explanation for this is that more carbonate is formed in High pH area but some of them migrated downward to sublayers over time. While, in the Low pH area, the pH was first stabilized in a neutral zone (Fig. 10) and then secondary carbonates were formed near the neutral range of pH. This hypothesis can be corroborated by the higher carbonate content of in the15-30 and 30–60 cm layers of the High pH area compared to the Low pH area (Results are not shown here). Another explanation could be that wollastonite dissolution slows down at higher pH (Haque et al., 2019b ; Haque et al., 2023 ), so it is expected that over a given period of time more wollastonite will be dissolved in soils of lower pH. As previous studies reported carbonate content enrichment in pan fraction of soil (Dudhaiya et al., 2019 ), we investigated this fraction in field trials as well (Fig. 6, shaded height of bars). The carbonate content of pan fraction of soil in “year zero” and after wollastonite application are higher than bulk samples except Thorndale field (the control sample of Woodstock was not analyzed for pan fraction as we didn’t have enough quantity of this sample). The SIC content of the pan fraction follows the same trend of accumulation. However, the ratio of carbonate content in pan fraction is lower than corresponding bulk samples in Dawn Euphemia (all three zones), while the trend is reversed in the Thorndale field. Samples were collected after six months and twelve months of wollastonite application from Thorndale and Dawn Euphemia fields, respectively. Hence, this might explain that finer particles were migrated to the subsoil layers in Dawn Euphemia field. 4.3.2.1 Tracking carbonate changes in deeper layers To track carbonate changes in deeper horizons of the Woodstock field, we extended the measurement and collection (with two different samplers: Dakota and Auger) down to 100 cm. The carbonate content of three layers of 0–15 cm, 15–30 cm and 30–60 cm are denoted in Fig. 7. These samples were collected with Dakota (tubular T-Style handle) sampler and the values are representative the average of whole field. These results denote that the carbonate content of the surficial layer (0–15 cm) is barely distinct between the first and second year, while deeper layers (15–30 cm and 30–60 cm) tend to be more enriched in the carbonate in the second year. It can be implied that accumulation of carbonates in deeper layers (particularly 30–60 cm) is associated with migration of Ca 2+ cations upon wollastonite dissolution or precipitation-dissolution-recrystallization of carbonates in deeper layers. Looking into the elemental composition of 30–60 cm layer of soil, CaO (2.87%) and MgO (1.68%) of this layer are akin to values of the surficial layer of this field reported in Fig. 5, while plainly far from control field data The auger sampler was employed to collect samples from deeper horizons of soil (up to 100 cm) at two locations in the field in two consecutive years (Fig. 8). In the first location (Core 1), after digging the soil up to 100 cm, we reached water table (or perched water table) in both sample collection episodes. Whereas the second location (Core 2) ended up in a layer of rocks and sampling became impractical at around 100 cm depth. As shown in Fig. 8, the carbonate content is generally in the lower range (5–10 times) at the Core 1 location (at the same depth range). While the carbonate content tends to increase in year 2 in Core 1 location (with a smaller deviation), carbonate content at Core 2 location depicts various shifts. Accordingly, shallower layers (0–30 cm and 30–60 cm) show improvement in carbonate content in the second year, while the deepest layer (60–100 cm) shows a decline in carbonate content (though with high standard deviation). Given the enrichment of carbonates in deeper layers (in the range of 100 to 250 times higher than newly formed carbonates) and the complexity of sampling in deep horizons, it is burdensome and uncertain to track and detect an increase in pedogenic carbonate formation due to wollastonite amendment even in long term. 3.3 Determination of sequestrated carbon in the form of pedogenic carbonate Based on bulk density, depth of sampling (15 cm), and carbonate accumulation, the sequestrated carbon in soil due to amendment with wollastonite was calculated and is presented in Fig. 9. Accordingly, more than 6 t CO 2 /ha was stabilized in Woodstock and Thorndale fields, corresponding to an efficiency (ratio of tonne of sequestrated CO 2 to applied wollastonite) of 0.42 and 0.33, respectively. In Dawn Euphemia field, the amount of sequestration varies between 0.52 (in the High pH area) and 1.29 (in the Low pH area) t CO 2 /ha. The sequestration efficiency in the Dawn Euphemia (0.05–0.13) field is much lower than the two other fields. Comparing results with previous field study conducted in Ontario, Haque et al. ( 2020a ) reported a lower amount of carbon sequestration (0.11–0.4 tonnes CO 2 /ha over a few weeks to a few months) with lower wollastonite dosage of application (1.25-5 t/ha). Our results denote higher rates of wollastonite application (e.g., 15–20 t/ha) still significantly proliferates the amount of stabilized carbonates. 3.4 Soil pH As demonstrated in Fig. 10, the pH of the soil was improved in all field trials, though the degree of change varies. In the Dawn Euphemia field, a larger upward shift of soil pH was observed in the Low pH area and Neutral area, with an average of 0.97 and 0.89 unit increase, respectively. On other hand, the High pH area experienced a milder change (0.38-unit increment). In the Thorndale field, the pH of soil elevated to pH > 7 (compared to pH < 5.5, before wollastonite application). In the Woodstock field, the pH is mildly higher in the amendment field (after one year of application) compared to the control area, nevertheless, the increment ceased in the second year. The pH measurement implies that the soil system response to change is a function of initial pH. Accordingly, the largest accrual of pH was observed in acidic soils (the Low pH area in Dawn Euphemia and Thorndale fields). Conversely, the pH value seems to be stabilized in an alkaline range (pH > 7), as is the case of the High pH area in Dawn Euphemia and Woodstock (Year 1 vs. Year 2) fields. Studies reporting improvement of soil pH due to ERW practice abound in the literature (Dietzen et al., 2018 ; Haque et al., 2020a ; Kelland et al., 2020 ; te Pas et al., 2023 ). In a field-scale experiment, Haque et al. ( 2020a ) outlined improvement of pH in soils amended with Wollastonite in, while the degree of change was improved over time. All of the soils investigated in the mentioned study were in the range of mildly acidic (5.9 < pH < 6.7), coming with a gentle rise in different intervals (a few months to three years). In another field study, only a slight increase in soil pH was observed due to the introduction of glacial rock flour (enriched in Ca and Mg-bearing silicate minerals) to acidic soil (pH around 5) (Dietzen et al., 2018 ). It can be deduced from miscellaneous studies that pH steps up due to ERW practice doesn’t follow a specific trend and is dependent on many factors, including practice management, harvested plants, the composition of the applied mineral, etc. (Dietzen et al., 2018 ; Jariwala et al., 2022 ; te Pas et al., 2023 ). 3.5 Soil Organic Matter The objective of LOI analysis was to see how wollastonite addition affects SOM. Due to the positive correlation between SOM and SOC (Ruiz Sinoga et al., 2012 ), it is possible to assess the impact of wollastonite on SOC. The results of LOI analyses are represented in Fig. 11. The general trend is a reduction in SOM after the wollastonite amendment, while the magnitude of alteration varies in different fields. In Dawn Euphemia field, SOM reduces in order of High pH zone (0.26% decrease), Neutral zone, and Low pH zone (with an inconsiderable depletion), respectively. The highest depletion is observed in the Thorndale field, with around 1% reduction in the SOM content. Since there was no “Year zero” collection in the Woodstock field, the SOM of the amended field was compared to neighboring area (as an indication of background value). The SOC of the amended field is higher than the neighboring area. However, this could be attributed to the different harvesting/management practices performed in these two pieces of field. Interestingly, the SOM of this field in the second year of collection decreased compared to the first year (and comparable to the value of the neighboring area). The results of SOM are in line with trends reported in the literature. We observed the same trend in the soil column experiment (Chap. 5 of present thesis) with a significant drop of SOM in surficial layers (e.g., 0–15 and 15–30 cm layers) of soil amended with wollastonite, while the SOM content of sub soil layers (30–45 and 45–60 cm) was found intact. Haque et al. ( 2019b ) reported a decline of SOC in soil samples mixed with crushed wollastonite (through a pot experiment). In another study conducted by te Pas et al. ( 2023 ), the alteration of SOC due to silicate mineral introduction (including wollastonite) was found insignificant. 4. Conclusion The result of this study adds more insights to the literature on the potential of ERW weathering practice (via wollastonite) as a method for stabilizing atmospheric carbon in the form of pedogenic carbonate on a field scale. The highest amount of sequestrated carbon due to wollastonite was equal to 6.60 t CO 2 /ha, corresponding to an efficiency of 0.33 (t CO 2 /t wollastonite). The soils with initially lower pH appeared to have greater capacity to sequester carbon based on the increase of carbon measured after application and hence higher carbon sequestration. In line with previous studies, the carbonate content of the pan fraction (< 50 µm) was higher than bulk samples. We detected signs of downward migration of carbonates into deeper layers of soil (e.g., up to 60 cm) is difficult. However, due to the complexity of sampling and large deviation of primary carbonates, tracking carbonates at deeper horizons (e.g., > 60 cm) was difficult. Wollastonite amendment was found effective in improving soil pH in different ranges (acidic, neutral, and alkaline), with a pronounced degree in acidic soils (e.g., from pH ≈ 5 to pH ≈ 6–7). While XRF analyses denoted CaO and MgO increment comes with wollastonite addition in most fields, XRD analyses can barely detect mineral phases associated with weathering products, particularly in soils undergoing lower dosages of wollastonite. Wollastonite amendment also reduced the SOM of field samples and has an inverse correlation with the amount of wollastonite addition. Our results also present some evidence of the downward movement of carbonates into subsoil layers, in line with our observation from our soil column experiment. Hence, it calls for the consideration of carbonate accumulation in deeper layers and local pH as part of carbon dioxide removal methods due to ERW practice. Figuring out these uncertainties could enhance- the acceptability of ERW as a reliable and enduring carbon sequestration approach to tackle climate change. References Ahmad, W., Singh, B., Dalal, R.C., Dijkstra, F.A., 2015. Carbon dynamics from carbonate dissolution in Australian agricultural soils. Soil Res. 53, 144-153. https://doi.org/10.1071/SR14060. Ameyu, T., 2019. A review on the potential effect of lime on soil properties and crop productivity improvements. J. Environ. Earth Sci. 9 (2), 17–23. https://doi.org/10.7176/jees/9-2-03. Andrews, M.G., Taylor, L.L., 2019. Combating Climate Change Through Enhanced Weathering of Agricultural Soils. Elements 15, 253–258. https://doi.org/10.2138/gselements.15.4.253. Beerling, D.J., Leake, J.R., Long, S.P., Scholes, J.D., Ton, J., Nelson, P.N., Bird, M., Kantzas,E., Taylor, L.L., Sarkar,B., Kelland, M., DeLucia, E., Kantola, I., Müller, C., Rau, G., Hansen, J., 2018. Farming with crops and rocks to address global climate, food and soil security. Nat. Plants 4,138–147. https://doi.org/10.1038/s41477-018-0108-y. Calabrese, S., Wild, B., Bertagni, M.B., Bourg, I.C., White, C., Cipolla, G., Noto, L.V., Porporato, A., 2022. Nano- to Global-scale Uncertainties in Terrestrial Enhanced Weathering. Environ Sci Tech 2022;56(22):15261–72. https://doi.org/10.1021/acs.est.2c03163. Dietzen, C., Harrison, R., Michelsen-Correa, S., 2018. Effectiveness of enhanced mineral weathering as a carbon sequestration tool and alternative to agricultural lime: an incubation experiment. Int. J. Greenh. Gas Control 74, 251–258. https://doi.org/10.1016/j.ijggc.2018.05.007. Dudhaiya, A., Haque, F., Fantucci, H., Santos, R.M., 2019. Characterization of physically fractionated wollastonite-amended agricultural soils. Minerals 9, 635. https://doi.org/10.3390/min9100635. Ferreira, T.R., Pires, L.F., Wildenschild, D., Brinatti, A.M., Borges, J.A.R., Auler, A.C., dos Reis, A.M.H., 2019. Lime application effects on soil aggregate properties: Use of the mean weight diameter and synchrotron-based X-ray μCT techniques. Geoderma 338, 585-596. https://doi.org/10.1016/j.geoderma.2018.10.035. Haque, F., Khalidy, R., Chiang, Y.W., Santos, R.M., 2023. Constraining the Capacity of Global Croplands to CO2 Drawdown via Mineral Weathering. ACS Earth Space Chem., in press. 10.1021/acsearthspacechem.2c00374. Haque, F., Chiang, Y.W., Santos, R.M., 2019a. Alkaline Mineral Soil Amendment: A Climate Change ‘Stabilization Wedge’? Energies 12, 2299. https://doi.org/10.3390/en12122299. Haque, F., Santos, R.M., Dutta, A., Thimmanagari, M., Chiang, Y.W., 2019b. Co-benefits of wollastonite weathering in agriculture: CO2 sequestration and promoted plant growth. ACS Omega 4 (1), 1425–1433. https://doi.org/10.1021/acsomega.8b02477. Haque, F., Santos, R.M., Chiang, Y.W., 2020a. CO 2 Sequestration by wollastonite-amended agricultural soils-An Ontario field study. Int. J. Greenh. Gas Control 97, 103017. https://doi.org/10.1016/j.ijggc.2020.103017. Haque, F., Chiang, Y.W., Santos, R.M., 2020b.Optimizing Inorganic Carbon Sequestration and Crop Yield With Wollastonite Soil Amendment in a Microplot Study. Front. Plant Sci. 11, 1012. https://doi.org/10.3389/fpls.2020.01012. Hartmann, J., West, A.J., Renforth, P., Kohler, P., De La Rocha, C.L., Wolf-gladrow, D.A., Dürr, H.H., Scheffran, J., Rocha, C.L.D.L., Wolf-gladrow, D.A., Dürr, H.H., Scheffran, J., De La Rocha, C.L., Wolf-gladrow, D.A., Dürr, H.H., Scheffran, J., 2013. Enhanced chemical weathering as a geoengineering strategy to reduce atmospheric carbon dioxide, supply nutrients, and mitigate ocean acidification. Rev. Geophys. 51, 113–149. https://doi.org/10.1002/rog.20004. Holland, J.E., Bennett, A.E., Newton, A.C., White, P.J., Mckenzie, B.M., 2017. Liming impacts on soils, crops and biodiversity in the UK: A review. Sci. Total. Environ. 610-611, 316-332. http://doi.org/10.1016/j.scitotenv.2017.08.020. Jariwala, H. Haque, F., Vanderburgt, S., Santos, R.M., Chiang, Y.W., 2022. Mineral-Soil-Plant-Nutrient Synergisms of Enhanced Weathering for Agriculture: Short-Term Investigations Using Fast-Weathering Wollastonite Skarn. Front. Plant Sci. 13, 929457. https://doi.org/10.3389/fpls.2022.929457 Jorat, M.E., Kraavi, K.E., Manning, D.A.C., 2022. Removal of atmospheric CO2 by engineered soils in infrastructure projects. J. Environ. Manage. 314, 115016. https://doi.org/10.1016/j.jenvman.2022.115016. Khalidy, R., Arnaud, E., Santos, R.M., 2022. Natural and human-induced factors on the accumulation and migration of pedogenic carbonate in soil: a review. Land 11, 1448. https://doi.org/10.3390/land11091448. Khalidy, R., Chiang, Y.W., Santos, R.M., 2023. Fate and migration of enhanced rock weathering products through soil horizons; implications of irrigation and percolation regimes. Catena 233, 107524. https://doi.org/10.1016/j.catena.2023.107524 Khalidy, R., Haque, F., Chiang, Y.W., Santos, R.M., 2021. Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils. J. Vis. Exp. 172, e61996. https://doi.org/10.3791/61996. Khalidy, R., Santos, R.M., 2021b. Assessment of geochemical modeling applications and research hot spots—a year in review. Environ. Geochem. Health 43, 3351–3374. https://doi.org/10.1007/s10653-021-00862-w. Khalidy, R., Santos, R.M., 2021a. The fate of atmospheric carbon sequestrated through weathering in mine tailings. Miner. Eng. 163, 106767. https://doi.org/10.1016/j.mineng.2020.106767. Kelemen, P.B., McQueen, N., Wilcox, J., Renforth, P., Dipple, G., Vankeuren, A.P., 2020. Engineered carbon mineralization in ultramafic rocks for CO2 removal from air: review and new insights. Chem. Geol. 550, 119628. https://doi.org/10.1016/j.chemgeo.2020.119628. Kelland, M.E., Wade, P.W., Lewis, A.L., Taylor, L.L., Sarkar, B., Andrews, M.G., Lomas, M.R., Cotton, T.E.A., Kemp, S.J., James, R.H., 2020. Increased yield and CO 2 sequestration potential with the C4 cereal Sorghum bicolor cultivated in basaltic rock dust-amended agricultural soil. Glob. Chang. Biol. 26, 3658–3676. https://doi.org/10.1111/gcb.15089. Lal, R., 2007. Carbon management in agricultural soils. Mitigation and Adaptation Strategies for Global Change 12, 303e322. https://doi.org/10.1007/s11027-006-9036-7. Li, J., Hitch, M., Power, I.M., Pan, Y., 2018. Integrated mineral carbonation of ultramafic mine deposits—A review. Minerals 8, 1–18. https://doi.org/10.3390/min8040147. Lindsey, R., Dahlman, L., 2020. Climate change: Global temperature. https:// www.climate.gov/news-features/understanding-climate/climate-change-globaltemperature (Accessed 14/09/2023). Manning, D.A.C., Renforth, P., Lopez-Capel, E., Robertson, S., Ghazireh, N., 2013. Carbonate precipitation in artificial soils produced from basaltic quarry fines and composts: An opportunity for passive carbon sequestration. Int. J. Greenh. Gas Control 17, 309-317. https://doi.org/10.1016/j.ijggc.2013.05.012. Millar, R., Fuglestvedt, J., Friedlingstein, P., Rogelj, J., Grubb, M.J., Matthews, H.D., Skeie, R.B., Forster, P.M., Frame, D.J., Allen, M.R., 2017. Emission budgets and pathways consistent with limiting warming to 1.5 °C. Nat. Geosci. 10, 741–747. https://doi.org/10.1038/ngeo3031. Pang, Z., Tayyab, M., Kong, C., Hu, C., Zhu, Z., Wei, X., Yuan, Z., 2019. Liming positively modulates microbial community composition and function of sugarcane fields. Agronomy 9, 808 https://doi.org/doi.org/10.3390/agronomy9120808. Rahmanihanzaki, M., Hemmati, A., 2022. A review of mineral carbonation by alkaline solidwaste. Int. J. Greenh. Gas Control 121, 103798. https://doi.org/10.1016/j.ijggc.2022.103798. Rayment, G.E., Higginson, F.R., 1992. Australian laboratory handbook of soil and water chemical methods. Inkata Press Pty Ltd. Renforth, P., Pogge von Strandmann, P.A.E., Henderson, G.M., 2015. The dissolution of olivine added to soil: Implications for enhanced weathering. Appl. Geochemistry 61, 109–118. https://doi.org/10.1016/j.apgeochem.2015.05.016. Ruiz Sinoga, J.D., Pariente, S., Diaz, A.R., Martinez Murillo, J. F., 2012. Variability of relationships between soil organic carbon and some soil properties in Mediterranean rangelands under different climatic conditions (South of Spain). Catena 94, 17-25. https://doi.org/10.1016/j.catena.2011.06.004. Sanderman, J., 2018. Can management induced changes in the carbonate system drive soil carbon sequestration? A review with particular focus on Australia. Agric. Ecosyst. Environ. 155, 70-77. https://doi.org/10.1016/j.agee.2012.04.015. Stanbery, C., Ghahremani, Z., Huber, D.P., Will, R., Benner, S.G., Glenn, N., Hanif, T., Spaete, L., Terhaar, D., Lohse, K.A., Seyfried, M., Freutel, W., Pierce, J.L., 2023. Controls on the presence and storage of soil inorganic carbon in a semi-arid watershed. Catena 225, 106980. https://doi.org/10.1016/j.catena.2023.106980. te Pas, E.E.E.M., Hagens, M., Comans, R.N.J., 2023. Assessment of the enhanced weathering potential of different silicate minerals to improve soil quality and sequester CO2. Front. Clim. 4, 954064 https://doi.org/10.3389/fclim.2022.954064. Wilson, S.A., Harrison, A.L., Dipple, G.M., Power, I.M., Barker, S.L.L., Ulrich Mayer, K., Fallon, S.J., Raudsepp, M., Southam, G., 2014. Offsetting of CO2 emissions by air capture in mine tailings at the Mount Keith Nickel Mine, Western Australia: rates, controls and prospects for carbon neutral mining. Int. J. Greenh. Gas Control 25, 121–140. https://doi.org/10.1016/j.ijggc.2014.04.002. Zamanian, K., Pustovoytov, K., Kuzyakov, Y., 2016. Pedogenic carbonates: Forms and formation processes. Earth Sci. Rev. 157, 1-17. https://doi.org/10.1016/j.earscirev.2016.03.003. Zamanian, K., Zhou, J., Kuzyakov, Y., 2021. Soil carbonates: the unaccounted, irrecoverable carbon source. Geoderma 384, 114817. https://doi.org/10.1016/j.geoderma.2020.114817. Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3851689","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":266368382,"identity":"8ceec1f6-a852-42ac-9791-509a648c8674","order_by":0,"name":"Reza Khalidy","email":"","orcid":"https://orcid.org/0000-0002-6769-9691","institution":"University of Guelph","correspondingAuthor":false,"prefix":"","firstName":"Reza","middleName":"","lastName":"Khalidy","suffix":""},{"id":266368383,"identity":"37ec904f-e6f9-458e-808c-7f6f9f326889","order_by":1,"name":"Yi Wai Chiang","email":"","orcid":"https://orcid.org/0000-0002-7798-9166","institution":"University of Guelph","correspondingAuthor":false,"prefix":"","firstName":"Yi","middleName":"Wai","lastName":"Chiang","suffix":""},{"id":266368384,"identity":"b1706281-0454-4cbf-b1fd-cd05ef169a19","order_by":2,"name":"Rafael M. Santos","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA30lEQVRIiWNgGAWjYBADOQhVwJBAjGrGBiBhDGEbkKAlsYFoLfLtZ48/+PDnXvqG4+3XJD4Y3MljYD/8AK8WgzN5iY0z24pzN5w5UyY5w+BZMQNPmgF+LQw5hs28DQm5G27kpEnzGBxObJBgwK9Fvv+NYTPPn4R0A5CWP2At7B/we+YG0BYetoQEgxvpx6QZwFp4CDjsxhvDmTPbEgxnnjnDbNlj8CyxjSengIDDcgw+fPiTIM93vP3hjR8VdxL72Y9vwO8wBAC75wADG7HqgYD9AVjLKBgFo2AUjAJ0AAAeNE04E6v0LQAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0002-8368-8618","institution":"University of Guelph","correspondingAuthor":true,"prefix":"","firstName":"Rafael","middleName":"M.","lastName":"Santos","suffix":""}],"badges":[],"createdAt":"2024-01-10 23:00:25","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-3851689/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3851689/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":49537619,"identity":"7a47479b-0fef-492a-8522-d551eb503dbb","added_by":"auto","created_at":"2024-01-12 16:34:38","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":431595,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ea) Experimental field located in Woodstock, ON b) Wollastonite application to the experimental field in Summer 2019 c) First phase of field sampling conducted in September 2020\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/5fbd93cf0b055883b30a4afc.jpg"},{"id":49537621,"identity":"e228f27e-879a-4d2c-9a14-49d0ac63a2f6","added_by":"auto","created_at":"2024-01-12 16:34:38","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":300556,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eExperimental field located in a) Dawn Euphemia b) Thorndale\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/3cfc433cdb71bbc4573138c2.jpg"},{"id":49538455,"identity":"caccac4a-778d-42e5-8fce-9586e45eaf74","added_by":"auto","created_at":"2024-01-12 16:50:38","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":157192,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eXRD spectra of wollastonite sourced from Canadian Wollastonite and used in the field studies with highlighting peaks of wollastonite, diopside and Albite in the sample.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/3ce85a27168c5ae5695c89f3.jpg"},{"id":49537620,"identity":"f8c10856-b2f1-46ed-a7cd-9d39ff4d3476","added_by":"auto","created_at":"2024-01-12 16:34:38","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":125379,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eXRD diffractograms of field soil samples before (above) and after (below) wollastonite application. a) Woodstock, b) Thorndale, c) Dawn Euphemia (neutral area), and d) Dawn Euphemia (HpH area).\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/6f8551e7e470205d49edaac3.jpg"},{"id":49538122,"identity":"df6be51e-6b4d-4a75-9ede-93c73107c99f","added_by":"auto","created_at":"2024-01-12 16:42:38","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":204173,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChange in elemental composition of soil samples after wollastonite application. The hollow and filled symbols are representative of before and after wollastonite treatment values, respectively. The plus, multiplication and asterisks signs are indicative of control, year one and year two collection of Woodstock field, respectively.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/a51ed8030a0d4d2579443a38.jpg"},{"id":49538697,"identity":"ddc731ac-4890-4274-a8ea-e04088bd0c10","added_by":"auto","created_at":"2024-01-12 16:58:38","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":140661,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe CaCO\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e(eqv) content in soil samples (0-15 cm layer) with yellow and green bars are indicative of before and after wollastonite application, respectively. The solid and shaded bars are representative of carbonate content in bulk sample and pan fraction (passed through 50 μm sieve), respectively.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/8e9d4408acfb1f8262a60efe.jpg"},{"id":49537623,"identity":"01a7e783-7ea3-4987-94ee-cf7719443425","added_by":"auto","created_at":"2024-01-12 16:34:38","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":116714,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe carbonate content of different layers of soil of Woodstock field, collected with Dakota sampler.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/d06a74f31d744c60cfdf92df.jpg"},{"id":49538456,"identity":"03fb046d-e565-4ece-8f00-d5125a23aa17","added_by":"auto","created_at":"2024-01-12 16:50:38","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":126518,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe carbonate content of core samples collected with Auger sample at Woodstock field.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/39567dc2282b1eee266b0b59.jpg"},{"id":49538120,"identity":"c5268910-58f8-4ba2-8810-d9f775acc8d1","added_by":"auto","created_at":"2024-01-12 16:42:38","extension":"jpg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":99259,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe amount of sequestrated carbon in terms of pedogenic carbonate formation vs. the efficiency in studied fields\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"9.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/5fdc89fcfc9b692571077e29.jpg"},{"id":49538121,"identity":"6619727f-baab-4069-914a-d7f51d2956df","added_by":"auto","created_at":"2024-01-12 16:42:38","extension":"jpg","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":162750,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe modification in soil pH after wollastonite application in field trials (yellow: before and green: after wollastonite application, the rightest bar represents the pH of Woodstock two years after application).\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"10.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/f07c80243fe190feada2a0e8.jpg"},{"id":49537629,"identity":"6864cb15-dd16-4d42-8977-a80cfc73cdb4","added_by":"auto","created_at":"2024-01-12 16:34:38","extension":"jpg","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":177807,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe change in soil SOM after wollastonite application in field trials (yellow: before and green: after wollastonite application, the rightest bar represents SOM of Woodstock two years after application).\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"11.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/3d7d64a6cb26ed22a8db6c61.jpg"},{"id":49539329,"identity":"e5d105ed-0b9a-48ec-b907-d932f36d587d","added_by":"auto","created_at":"2024-01-12 17:06:38","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1160746,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3851689/v1/581cf991-8ad1-4828-83c3-37b863a98191.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eTracking pedogenic carbonate formation and migration in agricultural soils amended with crushed wollastonite ore- Evidence from field trials\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eInduced from anthropogenic activities, fossil fuels emissions are the prime mover of atmospheric CO\u003csub\u003e2\u003c/sub\u003e concentration to 100 ppm above the pre-industrial range and global warming and climate change-related ramifications (Khalidy and Santos, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2021a\u003c/span\u003e; Millar et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Lindsey and Dahlman, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). As an urgent response, drawing up and scaling up carbon dioxide removal (CDR) technologies are needed to decelerate this trend (Kelemen et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Khalidy and Santos, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e; Rahmanihanzaki and Hemmati, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Among CDR technologies, mineral carbonation is being recognized as a long-term carbon storage sink using feedstocks that occur naturally in Earth terrestrial ecosystems (Oelkers et al., 2008; Wilson et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2014\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAs the third largest pool of carbon in the world, soil is deemed as an earth-shattering sink for carbon (Stanbery et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Zamanian et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Carbon storage might be accumulated in the forms of soil organic carbon (SOC) or soil inorganic carbon (SIC) in soil (Beerling et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Lal \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Sanderman 2012). The carbon sequestration as SOC, highly dependent on practice management (Sanderman 2012) and subjected to decarbonization (Jorat et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), is usually regulated through photosynthesis and the organic matter cycle (Haque et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2019b\u003c/span\u003e). SIC, on the other hand, is recognized as a stable pool, and its sequestration proceeds through weathering of alkaline metals (Haque et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2019a\u003c/span\u003e). As an endorsement of this method, the application of powdered silicate minerals (such as wollastonite, basalt, and dolerite) and crushed concrete is well acknowledged as the low-cost and low-energy method for uptaking carbon as SIC (Haque et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2019b\u003c/span\u003e; Kelland et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Manning et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Renforth et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2015\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis process, called enhanced rock weathering (ERW), gets underway as Ca and Mg cations become available in the soil-water system as silicate minerals dissolve (Andrews and Taylor, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Meanwhile, the dissolution of CO\u003csub\u003e2\u003c/sub\u003e, originating from the atmosphere or soil organic matter (SOM), in percolating water contributes to the formation of carbonic acid and promotes the release of Ca and Mg from silicate minerals (through bringing down pH) (Beerling et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). The formed carbonic acid eventually dissociates to bicarbonate and proton in the soil-water solution. Depending on the geochemistry of native soil, these practices conclude either in pedogenic carbonate formation in soil/subsoil profile or migration of bicarbonates into groundwater systems (Khalidy et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Hartmann et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2013\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eJorat et al. (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) estimated annual carbon sequestration of 33 and 17 t/ha as pedogenic carbonate due to crushed concrete and dolerite addition in urban soils, respectively. In the study conducted by Haque et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2020a\u003c/span\u003e), it was revealed both the weathering interval and dosage of Ca-rich silicate mineral (wollastonite) dosage have a positive correlation with the SIC accumulation rate (up to 6 t/ha after three years) in the agricultural fields of southwestern Ontario, Canada.\u003c/p\u003e \u003cp\u003eFrom an agronomy viewpoint, the co-benefits of ERW practice on plant growth (and vice versa) are well documented (Haque et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2019b\u003c/span\u003e; Haque et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2020b\u003c/span\u003e; Jariwala et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Kelland et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). The secretion of organic acids such as citric acid and maleic acid from plant roots boosts silicate minerals' dissolution and ameliorates the ERW process (Haque et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2019b\u003c/span\u003e). Furthermore, Haque et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2020a\u003c/span\u003e) demonstrated that increases of wollastonite application rates up to 10 and 5 kg/m\u003csup\u003e2\u003c/sup\u003e increase root biomass of alfalfa and soybean, respectively; however, higher dosages had a reverse effect on these plants. In another study, Jariwala et al. (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) reported consistent outcomes where wollastonite treatment supplied more available Si for plants in soil.\u003c/p\u003e \u003cp\u003eAs a conventional agricultural practice, liming aims to adjust the pH of acidic soil to a neutral zone through the addition of Ca-rich materials such as lime (CaCO\u003csub\u003e3\u003c/sub\u003e) and dolomite (MgCa(CO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e) (Sanderman 2012). The liming process improves plant productivity (through ameliorating nutrient availability and abiotic activities) and soil aggregation (Ameyu, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Fereira et al., 2019; Holland et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Pang et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). However, an imminent drawback of liming is emitting CO\u003csub\u003e2\u003c/sub\u003e into the atmosphere that can exceed 200 Mt C per year annually and is regarded as the second practice with the highest CO\u003csub\u003e2\u003c/sub\u003e flux just after soil acidification (Ahmad et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Sanderman, 2012; Zamanian et al., \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Therefore, ERW is alluded to as a substitution for liming, delivering coequal benefits to the agricultural and agronomy system, while turning over the carbon efflux into stabilizing carbon in soil and contributing to climate change mitigation.\u003c/p\u003e \u003cp\u003eThe procedure involving amending agricultural soil with wollastonite (e.g., determining the amount of wollastonite to apply per hectare and the method to spread it over the soil) was described by Haque et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2020a\u003c/span\u003e). However, the analysis of this study was limited to a very surficial layer of soil (0\u0026ndash;15 cm). Since weathering products (especially the finer fraction) are exposed to downward migration, we aimed to investigate the impact of the wollastonite amendment on the deeper horizons of three new agricultural fields in Southwestern Ontario. Two of these field trials were part of a lime replacement project, where the objective was to see how wollastonite ameliorates soil properties (particularly pH). For sampling soil samples in field locations, we followed a protocol that describes, in detail: (1) a soil sampling method to be used following soil silicate amendment, which accounts for the statistical significance of the analyzed soil data; (2) a soil fractionation method that improves the accuracy of quantifying changes in pedogenic inorganic carbonate pool as a result of enhanced silicate weathering, and (3) the calculation steps used to determine the SIC sequestration rate as a result of soil silicate amendment.\u003c/p\u003e"},{"header":"2. Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n\u003ch2\u003e2.1 Site Description\u003c/h2\u003e\n\u003cp\u003eThis study involves three field trial studies. The first experiment was conducted on an agricultural micro plot (soil type: Sandy loam, N 43˚14\u0026rsquo; W 80˚62\u0026rsquo;, surface area: 0.012 acres) harvested with rye in Woodstock, Ontario (ON) (Fig.\u0026nbsp;1). The objective of this field work was to monitor pedogenic carbonate formation over the vertical profile of soil (e.g., 0\u0026ndash;60 cm). A dosage of 15 t/ha of wollastonite was applied to the area in the Summer 2019. The soil samples were collected at different depths on a yearly basis to track changes in the pedogenic carbonate pool in soil. The first and second sample collections were concluded in Fall 2020 and Fall 2021, respectively.\u003c/p\u003e\n\u003cp\u003eThe objective of two other field trials was to investigate wollastonite's impact on plants\u0026rsquo; growth and soil health (liming replacement). One of the fields, located in Dawn Euphemia, ON (soil type: Silt clay, N 42\u0026deg;42\u0026rsquo; W 82\u0026deg;03\u0026rsquo;) (Fig.\u0026nbsp;2.a), was harvested with soybean, wheat, and corn in 2021, 2022 and 2023, respectively. The wollastonite with the rate of 10 t/ha was applied to this field in late Spring 2021. This field is 145 acres and characterized by three discrete zones of low pH, neutral pH (strip area), and high pH areas. The sampling (after wollastonite application) from this field was conducted in late April 2022. The other field is located in Thorndale, ON (soil type: Silt loam, N 43\u0026deg;07\u0026rsquo; W 81\u0026deg;10\u0026rsquo;) (Fig.\u0026nbsp;2.b) and is harvested with a three-crop rotation (wheat, corn, and soybean) system. The wollastonite with an application rate of around 20 t/ha was applied to this field (50 acres) in late Spring 2021. The first phase of sampling from this field was conducted in October 2021. The core soils were collected from this field (before wollastonite application as \u0026ldquo;year 0\u0026rdquo; data) to investigate the impact of enhanced weathering on SIC content, pH, and physical characterization of soil.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n\u003ch2\u003e2.2 Wollastonite Characterization\u003c/h2\u003e\n\u003cp\u003eThe wollastonite used for field trials was sourced from Canadian Wollastonite Inc. (Canada), mined near Kingston, ON. The main characterization of the wollastonite ore from this source is demonstrated in Table\u0026nbsp;1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable \u003c/strong\u003e\u003cstrong\u003e1\u003c/strong\u003e. \u003cstrong\u003eCharacterization (BET, particle size distribution, and elemental composition) of wollastonite sourced from Canadian Wollastonite.\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tabc\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eBET surface area (m\u003csup\u003e2\u003c/sup\u003e/g)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003e0.198\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eParticle size (volume %):\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026gt;\u0026thinsp;500 \u0026micro;m\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e11.05\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e250\u0026ndash;500 \u0026micro;m\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e47.21\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e63\u0026ndash;250 \u0026micro;m\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e35.55\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e32\u0026ndash;63 \u0026micro;m\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2.18\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026lt;\u0026thinsp;32 \u0026micro;m\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3.17\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eXRF(mass %)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNa\u003csub\u003e2\u003c/sub\u003eO\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2.63\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMgO\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e6.03\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAl\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e5.29\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSiO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e56.62\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eP\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.07\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.41\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eCl\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.12\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eK\u003csub\u003e2\u003c/sub\u003eO\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e1.32\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eCaO\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e23.97\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTiO\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.24\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eV\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.04\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eCr\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.02\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMnO\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.06\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eFe\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2.04\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSrO\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.17\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eLOI\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.88\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eAccording to the elemental composition of the wollastonite (Table\u0026nbsp;1), the mineral contains Mg, which could be indicative of diopside (MgCaSi\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e6\u003c/sub\u003e), have been found to co-exist with wollastonite. This can be corroborated by looking into XRD pattern of the sample, where peaks of diopside are conspicuous along with those belonging to wollastonite. (Fig.\u0026nbsp;3).\u003c/p\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n\u003ch2\u003e2.4. Sample collection and soil analyses\u003c/h2\u003e\n\u003cp\u003eIn the Woodstock field (Fig.\u0026nbsp;1), the samples were collected from three layers of 0\u0026ndash;15, 15\u0026ndash;30 and 30\u0026ndash;60 cm layers of soil one year and two years after wollastonite application. Samples were collected from surficial layer (0\u0026ndash;15) cm layer of two other fields (Thorndale and Dawn Euphemia, Fig.\u0026nbsp;2), before and after wollastonite application.\u003c/p\u003e\n\u003cp\u003eThe method for collecting, preparing and analyzing soil carbonate content is described in detail in our previous study (Khalidy et al., \u003cspan class=\"CitationRef\"\u003e2021\u003c/span\u003e). Accordingly, after transporting to lab, samples were air-dried. The soil samples' carbonate content (soil inorganic carbon (SIC) in gCO\u003csub\u003e2\u003c/sub\u003e\u0026middot;(kg\u0026middot;soil)\u003csup\u003e\u0026minus;1\u003c/sup\u003e) was determined using the calcimetry technique. This method involved adding 20 ml of MiliQ water to the soil samples in an Erlenmeyer flask followed by the addition of 7 ml of 4 M HCL (Khalidy et al. \u003cspan class=\"CitationRef\"\u003e2021\u003c/span\u003e; Khalidy et al., \u003cspan class=\"CitationRef\"\u003e2023\u003c/span\u003e). To obtain the pan fraction (particles finer than 710 \u0026micro;m), soil samples were placed in oven at 105˚ C overnight. Then they were placed on a sieve shaker consisting of different mesh sizes (710 to 50 \u0026micro;m), at 60 rpm for 15 min. Finally, the carbonate content of pan fraction was compared with the bulk samples.\u003c/p\u003e\n\u003cp\u003eTo determine the pH of soil samples, 5:1 volumetric ratio of water was added to the soil, and the formed suspension was placed for 1 hour on a shaker (Rayment and Higginson, \u003cspan class=\"CitationRef\"\u003e1992\u003c/span\u003e). Then, the suspension was kept motionless for another hour before measurement using a pH meter (Oakton pH 700 Benchtop meter). To account for the changes in the mineral phases of soil samples due to wollastonite treatment, X-ray diffraction (XRD, Panalytical Empyrean) and X-ray fluorescence (XRF, Rigaku Supermini 200) analyses were employed. The multipoint Brunauer-Emmett-Teller (BET) surface area and particle size distribution of wollastonite were determined using a physisorption analyzer (Quantachrome Autosorb iQ) and laser diffraction (Malvern Mastersize SM), respectively.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n\u003ch2\u003e2.5. Data Analyses\u003c/h2\u003e\n\u003cp\u003eAll readings of experimental analyses on soil and leachate samples were conducted in triplicate, and the mean of results was reported (along with standard error). To discern the statistical significance of treatments (control vs. wollastonite amendment), the Independent Samples T-Test was used in IBM SPSS software.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3. Results and Discussion","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n\u003ch2\u003e3.1 Mineralogy and elemental composition\u003c/h2\u003e\n\u003cp\u003eFigure 4 demonstrates the XRD diffractograms of soils amended with wollastonite and the corresponding control soils. Due to the complexity of soil composition, quantifying the mineral phases is challenging (Haque et al., \u003cspan class=\"CitationRef\"\u003e2020a\u003c/span\u003e); therefore, the peaks were identified qualitatively. According to Fig.\u0026nbsp;4, Quartz and Albite are present in samples from all locations, while there are minor differences in the other phases. Regarding minor phases, microcline is present in all locations, while muscovite was only detected in Woodstock and Dawn Euphemia soils.\u003c/p\u003e\n\u003cp\u003eWhen it comes to weathering products, minuscule peaks of calcite are detectable in the amended samples. Several wollastonite and diopside peaks are visible in Thorndale field\u0026rsquo;s soil, while are absent in other fields. Comparing the XRD results of field soil and our soil column experiment (discussed in Chap.\u0026nbsp;5), it can be deduced that wollastonite/diopside phases are much more distinct in the latter. This can be explained in two ways. First, a higher wollastonite dosage was applied in the column experiment (50 t/ha vs. 5\u0026ndash;20 t/ha in the field trials), so it is more probable that a higher amount of unweathered portion remains in the soil for a longer time. Interestingly, the only occurrence of wollastonite peaks in field samples corresponds to the highest dosage of wollastonite application (Thorndale location, 20 t/ha) among field trials. Furthermore, field trials took longer (6 months to 1 year) than column experiment (5 months), which left more time for wollastonite to weather in soil. As discussed by Calabrese et al. (\u003cspan class=\"CitationRef\"\u003e2022\u003c/span\u003e), ambient factors such as climate and abiotic agents could boost mineral dissolution in the field scale compared to laboratory condition.\u003c/p\u003e\n\u003cp\u003eXRF analyses denote an increment of CaO% in all samples, while MgO% follows the same trend except for Dawn Euphemia (DE) field (high pH area), showing a slight decrease (Fig.\u0026nbsp;5). The highest amendment occurred in the Woodstock field (0.7 and 0.5% increase in the CaO and MgO contents, respectively). Looking at some other elements (Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e,Fe\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e and SiO\u003csub\u003e2\u003c/sub\u003e) there is no clear trend after the wollastonite introduction. For example, the content of SiO\u003csub\u003e2\u003c/sub\u003e shows two different trends of increase (DE, Neutral Area and Thorndale Field) and decrease (Woodstock, DE Low pH and High pH areas).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n\u003ch2\u003e3.2 Carbonate content\u003c/h2\u003e\n\u003cp\u003eThe carbonate content of field soils before and after wollastonite application are illustrated in Fig.\u0026nbsp;6. The SIC in Woodstock, Thorndale and Neutral area of Dawn Euphemia are 2.52, 1.71 and 2.46 (gr, CaCO\u003csub\u003e3\u003c/sub\u003e (eqv)/(kg,soil)), respectively (in Woodstock field, no soil collection was conducted before application and soil obtained from neighborhood field is regarded as \u0026ldquo;before application). The carbonate accumulation in Woodstock and Thorndale fields is notable, corresponding to more than 4 and 6 times higher compared to prior application contents, respectively. In the Dawn Euphemia field, the SIC of field soils before wollastonite application has a negative correlation with initial pH and is in the range of 0.62 (in the Low pH area of the Dawn Euphemia field) and 4.76 (in the High pH area of Dawn Euphemia) (g, CaCO3 (eqv)/(kg,soil)). Although the accumulation of carbonates in this field is lower than in the other fields, the trend of increment is in agreement with local SIC and pH of soil. Accordingly, the net carbonate accumulation in Low pH, Neutral and High pH areas equals 1.93, 1.10 and 0.78 (g, CaCO\u003csub\u003e3\u003c/sub\u003e (eqv)/(kg,soil)), respectively.\u003c/p\u003e\n\u003cp\u003eThese findings imply that the lower the pH of soil, the higher the accumulation of pedogenic carbonate in the Dawn Euphemia field. However, previous studies have shown increasing pH favors pedogenic carbonate formation, while wollastonite dissolution is promoted in low pH soil (Haque et al., \u003cspan class=\"CitationRef\"\u003e2019b\u003c/span\u003e). One explanation for this is that more carbonate is formed in High pH area but some of them migrated downward to sublayers over time. While, in the Low pH area, the pH was first stabilized in a neutral zone (Fig.\u0026nbsp;10) and then secondary carbonates were formed near the neutral range of pH. This hypothesis can be corroborated by the higher carbonate content of in the15-30 and 30\u0026ndash;60 cm layers of the High pH area compared to the Low pH area (Results are not shown here). Another explanation could be that wollastonite dissolution slows down at higher pH (Haque et al., \u003cspan class=\"CitationRef\"\u003e2019b\u003c/span\u003e; Haque et al., \u003cspan class=\"CitationRef\"\u003e2023\u003c/span\u003e), so it is expected that over a given period of time more wollastonite will be dissolved in soils of lower pH.\u003c/p\u003e\n\u003cp\u003eAs previous studies reported carbonate content enrichment in pan fraction of soil (Dudhaiya et al., \u003cspan class=\"CitationRef\"\u003e2019\u003c/span\u003e), we investigated this fraction in field trials as well (Fig.\u0026nbsp;6, shaded height of bars). The carbonate content of pan fraction of soil in \u0026ldquo;year zero\u0026rdquo; and after wollastonite application are higher than bulk samples except Thorndale field (the control sample of Woodstock was not analyzed for pan fraction as we didn\u0026rsquo;t have enough quantity of this sample). The SIC content of the pan fraction follows the same trend of accumulation. However, the ratio of carbonate content in pan fraction is lower than corresponding bulk samples in Dawn Euphemia (all three zones), while the trend is reversed in the Thorndale field. Samples were collected after six months and twelve months of wollastonite application from Thorndale and Dawn Euphemia fields, respectively. Hence, this might explain that finer particles were migrated to the subsoil layers in Dawn Euphemia field.\u003c/p\u003e\n\u003cdiv id=\"Sec10\" class=\"Section3\"\u003e\n\u003ch2\u003e4.3.2.1 Tracking carbonate changes in deeper layers\u003c/h2\u003e\n\u003cp\u003eTo track carbonate changes in deeper horizons of the Woodstock field, we extended the measurement and collection (with two different samplers: Dakota and Auger) down to 100 cm. The carbonate content of three layers of 0\u0026ndash;15 cm, 15\u0026ndash;30 cm and 30\u0026ndash;60 cm are denoted in Fig.\u0026nbsp;7. These samples were collected with Dakota (tubular T-Style handle) sampler and the values are representative the average of whole field. These results denote that the carbonate content of the surficial layer (0\u0026ndash;15 cm) is barely distinct between the first and second year, while deeper layers (15\u0026ndash;30 cm and 30\u0026ndash;60 cm) tend to be more enriched in the carbonate in the second year. It can be implied that accumulation of carbonates in deeper layers (particularly 30\u0026ndash;60 cm) is associated with migration of Ca\u003csup\u003e2+\u003c/sup\u003e cations upon wollastonite dissolution or precipitation-dissolution-recrystallization of carbonates in deeper layers. Looking into the elemental composition of 30\u0026ndash;60 cm layer of soil, CaO (2.87%) and MgO (1.68%) of this layer are akin to values of the surficial layer of this field reported in Fig.\u0026nbsp;5, while plainly far from control field data\u003c/p\u003e\n\u003cp\u003eThe auger sampler was employed to collect samples from deeper horizons of soil (up to 100 cm) at two locations in the field in two consecutive years (Fig.\u0026nbsp;8). In the first location (Core 1), after digging the soil up to 100 cm, we reached water table (or perched water table) in both sample collection episodes. Whereas the second location (Core 2) ended up in a layer of rocks and sampling became impractical at around 100 cm depth. As shown in Fig.\u0026nbsp;8, the carbonate content is generally in the lower range (5\u0026ndash;10 times) at the Core 1 location (at the same depth range). While the carbonate content tends to increase in year 2 in Core 1 location (with a smaller deviation), carbonate content at Core 2 location depicts various shifts.\u003c/p\u003e\n\u003cp\u003eAccordingly, shallower layers (0\u0026ndash;30 cm and 30\u0026ndash;60 cm) show improvement in carbonate content in the second year, while the deepest layer (60\u0026ndash;100 cm) shows a decline in carbonate content (though with high standard deviation). Given the enrichment of carbonates in deeper layers (in the range of 100 to 250 times higher than newly formed carbonates) and the complexity of sampling in deep horizons, it is burdensome and uncertain to track and detect an increase in pedogenic carbonate formation due to wollastonite amendment even in long term.\u003c/p\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n\u003ch2\u003e3.3 Determination of sequestrated carbon in the form of pedogenic carbonate\u003c/h2\u003e\n\u003cp\u003eBased on bulk density, depth of sampling (15 cm), and carbonate accumulation, the sequestrated carbon in soil due to amendment with wollastonite was calculated and is presented in Fig.\u0026nbsp;9. Accordingly, more than 6 t CO\u003csub\u003e2\u003c/sub\u003e/ha was stabilized in Woodstock and Thorndale fields, corresponding to an efficiency (ratio of tonne of sequestrated CO\u003csub\u003e2\u003c/sub\u003e to applied wollastonite) of 0.42 and 0.33, respectively. In Dawn Euphemia field, the amount of sequestration varies between 0.52 (in the High pH area) and 1.29 (in the Low pH area) t CO\u003csub\u003e2\u003c/sub\u003e/ha. The sequestration efficiency in the Dawn Euphemia (0.05\u0026ndash;0.13) field is much lower than the two other fields.\u003c/p\u003e\n\u003cp\u003eComparing results with previous field study conducted in Ontario, Haque et al. (\u003cspan class=\"CitationRef\"\u003e2020a\u003c/span\u003e) reported a lower amount of carbon sequestration (0.11\u0026ndash;0.4 tonnes CO\u003csub\u003e2\u003c/sub\u003e/ha over a few weeks to a few months) with lower wollastonite dosage of application (1.25-5 t/ha). Our results denote higher rates of wollastonite application (e.g., 15\u0026ndash;20 t/ha) still significantly proliferates the amount of stabilized carbonates.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n\u003ch2\u003e3.4 Soil pH\u003c/h2\u003e\n\u003cp\u003eAs demonstrated in Fig.\u0026nbsp;10, the pH of the soil was improved in all field trials, though the degree of change varies. In the Dawn Euphemia field, a larger upward shift of soil pH was observed in the Low pH area and Neutral area, with an average of 0.97 and 0.89 unit increase, respectively. On other hand, the High pH area experienced a milder change (0.38-unit increment). In the Thorndale field, the pH of soil elevated to pH\u0026thinsp;\u0026gt;\u0026thinsp;7 (compared to pH\u0026thinsp;\u0026lt;\u0026thinsp;5.5, before wollastonite application). In the Woodstock field, the pH is mildly higher in the amendment field (after one year of application) compared to the control area, nevertheless, the increment ceased in the second year.\u003c/p\u003e\n\u003cp\u003eThe pH measurement implies that the soil system response to change is a function of initial pH. Accordingly, the largest accrual of pH was observed in acidic soils (the Low pH area in Dawn Euphemia and Thorndale fields). Conversely, the pH value seems to be stabilized in an alkaline range (pH\u0026thinsp;\u0026gt;\u0026thinsp;7), as is the case of the High pH area in Dawn Euphemia and Woodstock (Year 1 vs. Year 2) fields.\u003c/p\u003e\n\u003cp\u003eStudies reporting improvement of soil pH due to ERW practice abound in the literature (Dietzen et al., \u003cspan class=\"CitationRef\"\u003e2018\u003c/span\u003e; Haque et al., \u003cspan class=\"CitationRef\"\u003e2020a\u003c/span\u003e; Kelland et al., \u003cspan class=\"CitationRef\"\u003e2020\u003c/span\u003e; te Pas et al., \u003cspan class=\"CitationRef\"\u003e2023\u003c/span\u003e). In a field-scale experiment, Haque et al. (\u003cspan class=\"CitationRef\"\u003e2020a\u003c/span\u003e) outlined improvement of pH in soils amended with Wollastonite in, while the degree of change was improved over time. All of the soils investigated in the mentioned study were in the range of mildly acidic (5.9\u0026thinsp;\u0026lt;\u0026thinsp;pH\u0026thinsp;\u0026lt;\u0026thinsp;6.7), coming with a gentle rise in different intervals (a few months to three years). In another field study, only a slight increase in soil pH was observed due to the introduction of glacial rock flour (enriched in Ca and Mg-bearing silicate minerals) to acidic soil (pH around 5) (Dietzen et al., \u003cspan class=\"CitationRef\"\u003e2018\u003c/span\u003e). It can be deduced from miscellaneous studies that pH steps up due to ERW practice doesn\u0026rsquo;t follow a specific trend and is dependent on many factors, including practice management, harvested plants, the composition of the applied mineral, etc. (Dietzen et al., \u003cspan class=\"CitationRef\"\u003e2018\u003c/span\u003e; Jariwala et al., \u003cspan class=\"CitationRef\"\u003e2022\u003c/span\u003e; te Pas et al., \u003cspan class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n\u003ch2\u003e3.5 Soil Organic Matter\u003c/h2\u003e\n\u003cp\u003eThe objective of LOI analysis was to see how wollastonite addition affects SOM. Due to the positive correlation between SOM and SOC (Ruiz Sinoga et al., \u003cspan class=\"CitationRef\"\u003e2012\u003c/span\u003e), it is possible to assess the impact of wollastonite on SOC. The results of LOI analyses are represented in Fig.\u0026nbsp;11. The general trend is a reduction in SOM after the wollastonite amendment, while the magnitude of alteration varies in different fields.\u003c/p\u003e\n\u003cp\u003eIn Dawn Euphemia field, SOM reduces in order of High pH zone (0.26% decrease), Neutral zone, and Low pH zone (with an inconsiderable depletion), respectively. The highest depletion is observed in the Thorndale field, with around 1% reduction in the SOM content. Since there was no \u0026ldquo;Year zero\u0026rdquo; collection in the Woodstock field, the SOM of the amended field was compared to neighboring area (as an indication of background value). The SOC of the amended field is higher than the neighboring area. However, this could be attributed to the different harvesting/management practices performed in these two pieces of field. Interestingly, the SOM of this field in the second year of collection decreased compared to the first year (and comparable to the value of the neighboring area).\u003c/p\u003e\n\u003cp\u003eThe results of SOM are in line with trends reported in the literature. We observed the same trend in the soil column experiment (Chap.\u0026nbsp;5 of present thesis) with a significant drop of SOM in surficial layers (e.g., 0\u0026ndash;15 and 15\u0026ndash;30 cm layers) of soil amended with wollastonite, while the SOM content of sub soil layers (30\u0026ndash;45 and 45\u0026ndash;60 cm) was found intact. Haque et al. (\u003cspan class=\"CitationRef\"\u003e2019b\u003c/span\u003e) reported a decline of SOC in soil samples mixed with crushed wollastonite (through a pot experiment). In another study conducted by te Pas et al. (\u003cspan class=\"CitationRef\"\u003e2023\u003c/span\u003e), the alteration of SOC due to silicate mineral introduction (including wollastonite) was found insignificant.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThe result of this study adds more insights to the literature on the potential of ERW weathering practice (via wollastonite) as a method for stabilizing atmospheric carbon in the form of pedogenic carbonate on a field scale. The highest amount of sequestrated carbon due to wollastonite was equal to 6.60 t CO\u003csub\u003e2\u003c/sub\u003e/ha, corresponding to an efficiency of 0.33 (t CO\u003csub\u003e2\u003c/sub\u003e/t wollastonite). The soils with initially lower pH appeared to have greater capacity to sequester carbon based on the increase of carbon measured after application and hence higher carbon sequestration. In line with previous studies, the carbonate content of the pan fraction (\u0026lt;\u0026thinsp;50 \u0026micro;m) was higher than bulk samples. We detected signs of downward migration of carbonates into deeper layers of soil (e.g., up to 60 cm) is difficult. However, due to the complexity of sampling and large deviation of primary carbonates, tracking carbonates at deeper horizons (e.g., \u0026gt; 60 cm) was difficult. Wollastonite amendment was found effective in improving soil pH in different ranges (acidic, neutral, and alkaline), with a pronounced degree in acidic soils (e.g., from pH\u0026thinsp;\u0026asymp;\u0026thinsp;5 to pH\u0026thinsp;\u0026asymp;\u0026thinsp;6\u0026ndash;7). While XRF analyses denoted CaO and MgO increment comes with wollastonite addition in most fields, XRD analyses can barely detect mineral phases associated with weathering products, particularly in soils undergoing lower dosages of wollastonite. Wollastonite amendment also reduced the SOM of field samples and has an inverse correlation with the amount of wollastonite addition. Our results also present some evidence of the downward movement of carbonates into subsoil layers, in line with our observation from our soil column experiment. Hence, it calls for the consideration of carbonate accumulation in deeper layers and local pH as part of carbon dioxide removal methods due to ERW practice. Figuring out these uncertainties could enhance- the acceptability of ERW as a reliable and enduring carbon sequestration approach to tackle climate change.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAhmad, W., Singh, B., Dalal, R.C., Dijkstra, F.A., 2015. Carbon dynamics from carbonate dissolution in Australian agricultural soils. Soil Res. 53, 144-153. https://doi.org/10.1071/SR14060.\u003c/li\u003e\n\u003cli\u003eAmeyu, T., 2019. A review on the potential effect of lime on soil properties and crop productivity improvements. J. Environ. Earth Sci. 9 (2), 17\u0026ndash;23. https://doi.org/10.7176/jees/9-2-03.\u003c/li\u003e\n\u003cli\u003eAndrews, M.G., Taylor, L.L., 2019. Combating Climate Change Through Enhanced Weathering of Agricultural Soils. Elements 15, 253\u0026ndash;258. https://doi.org/10.2138/gselements.15.4.253.\u003c/li\u003e\n\u003cli\u003eBeerling, D.J., Leake, J.R., Long, S.P., Scholes, J.D., Ton, J., Nelson, P.N., Bird, M., Kantzas,E., Taylor, L.L., Sarkar,B., Kelland, M., DeLucia, E., Kantola, I., M\u0026uuml;ller, C., Rau, G., Hansen, J., 2018. Farming with crops and rocks to address global climate, food and soil security. Nat. Plants 4,138\u0026ndash;147. https://doi.org/10.1038/s41477-018-0108-y.\u003c/li\u003e\n\u003cli\u003eCalabrese, S., Wild, B., Bertagni, M.B., Bourg, I.C., White, C., Cipolla, G., Noto, L.V., Porporato, A., 2022. Nano- to Global-scale Uncertainties in Terrestrial Enhanced Weathering. Environ Sci Tech 2022;56(22):15261\u0026ndash;72. https://doi.org/10.1021/acs.est.2c03163.\u003c/li\u003e\n\u003cli\u003eDietzen, C., Harrison, R., Michelsen-Correa, S., 2018. Effectiveness of enhanced mineral weathering as a carbon sequestration tool and alternative to agricultural lime: an incubation experiment. Int. J. Greenh. Gas Control 74, 251\u0026ndash;258. https://doi.org/10.1016/j.ijggc.2018.05.007.\u003c/li\u003e\n\u003cli\u003eDudhaiya, A., Haque, F., Fantucci, H., Santos, R.M., 2019. Characterization of physically fractionated wollastonite-amended agricultural soils. Minerals 9, 635. https://doi.org/10.3390/min9100635.\u003c/li\u003e\n\u003cli\u003eFerreira, T.R., Pires, L.F., Wildenschild, D., Brinatti, A.M., Borges, J.A.R., Auler, A.C., dos Reis, A.M.H., 2019. Lime application effects on soil aggregate properties: Use of the mean weight diameter and synchrotron-based X-ray \u0026mu;CT techniques. Geoderma 338, 585-596. https://doi.org/10.1016/j.geoderma.2018.10.035.\u003c/li\u003e\n\u003cli\u003eHaque, F., Khalidy, R., Chiang, Y.W., Santos, R.M., 2023. Constraining the Capacity of Global Croplands to CO2 Drawdown via Mineral Weathering. ACS Earth Space Chem., in press. 10.1021/acsearthspacechem.2c00374.\u003c/li\u003e\n\u003cli\u003eHaque, F., Chiang, Y.W., Santos, R.M., 2019a. Alkaline Mineral Soil Amendment: A Climate Change \u0026lsquo;Stabilization Wedge\u0026rsquo;? Energies 12, 2299. https://doi.org/10.3390/en12122299. \u003c/li\u003e\n\u003cli\u003eHaque, F., Santos, R.M., Dutta, A., Thimmanagari, M., Chiang, Y.W., 2019b. Co-benefits of wollastonite weathering in agriculture: CO2 sequestration and promoted plant growth. ACS Omega 4 (1), 1425\u0026ndash;1433. https://doi.org/10.1021/acsomega.8b02477.\u003c/li\u003e\n\u003cli\u003eHaque, F., Santos, R.M., Chiang, Y.W., 2020a. CO\u003csub\u003e2\u003c/sub\u003e Sequestration by wollastonite-amended agricultural soils-An Ontario field study. Int. J. Greenh. Gas Control 97, 103017. https://doi.org/10.1016/j.ijggc.2020.103017.\u003c/li\u003e\n\u003cli\u003eHaque, F., Chiang, Y.W., Santos, R.M., 2020b.Optimizing Inorganic Carbon Sequestration and Crop Yield With Wollastonite Soil Amendment in a Microplot Study. Front. Plant Sci. 11, 1012. https://doi.org/10.3389/fpls.2020.01012.\u003c/li\u003e\n\u003cli\u003eHartmann, J., West, A.J., Renforth, P., Kohler, P., De La Rocha, C.L., Wolf-gladrow, D.A., D\u0026uuml;rr, H.H., Scheffran, J., Rocha, C.L.D.L., Wolf-gladrow, D.A., D\u0026uuml;rr, H.H., Scheffran, J., De La Rocha, C.L., Wolf-gladrow, D.A., D\u0026uuml;rr, H.H., Scheffran, J., 2013. Enhanced chemical weathering as a geoengineering strategy to reduce atmospheric carbon dioxide, supply nutrients, and mitigate ocean acidification. Rev. Geophys. 51, 113\u0026ndash;149. https://doi.org/10.1002/rog.20004.\u003c/li\u003e\n\u003cli\u003eHolland, J.E., Bennett, A.E., Newton, A.C., White, P.J., Mckenzie, B.M., 2017. Liming impacts on soils, crops and biodiversity in the UK: A review. Sci. Total. Environ. 610-611, 316-332. http://doi.org/10.1016/j.scitotenv.2017.08.020.\u003c/li\u003e\n\u003cli\u003eJariwala, H. Haque, F., Vanderburgt, S., Santos, R.M., Chiang, Y.W., 2022. Mineral-Soil-Plant-Nutrient Synergisms of Enhanced Weathering for Agriculture: Short-Term Investigations Using Fast-Weathering Wollastonite Skarn. Front. Plant Sci. 13, 929457. https://doi.org/10.3389/fpls.2022.929457\u003c/li\u003e\n\u003cli\u003eJorat, M.E., Kraavi, K.E., Manning, D.A.C., 2022. Removal of atmospheric CO2 by engineered soils in infrastructure projects. J. Environ. Manage. 314, 115016. https://doi.org/10.1016/j.jenvman.2022.115016.\u003c/li\u003e\n\u003cli\u003eKhalidy, R., Arnaud, E., Santos, R.M., 2022. Natural and human-induced factors on the accumulation and migration of pedogenic carbonate in soil: a review. Land 11, 1448. https://doi.org/10.3390/land11091448.\u003c/li\u003e\n\u003cli\u003eKhalidy, R., Chiang, Y.W., Santos, R.M., 2023. Fate and migration of enhanced rock weathering products through soil horizons; implications of irrigation and percolation regimes. Catena 233, 107524. https://doi.org/10.1016/j.catena.2023.107524\u003c/li\u003e\n\u003cli\u003eKhalidy, R., Haque, F., Chiang, Y.W., Santos, R.M., 2021. Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils. J. Vis. Exp. 172, e61996. https://doi.org/10.3791/61996.\u003c/li\u003e\n\u003cli\u003eKhalidy, R., Santos, R.M., 2021b. Assessment of geochemical modeling applications and research hot spots\u0026mdash;a year in review. Environ. Geochem. Health 43, 3351\u0026ndash;3374. https://doi.org/10.1007/s10653-021-00862-w.\u003c/li\u003e\n\u003cli\u003eKhalidy, R., Santos, R.M., 2021a. The fate of atmospheric carbon sequestrated through weathering in mine tailings. Miner. Eng. 163, 106767. https://doi.org/10.1016/j.mineng.2020.106767.\u003c/li\u003e\n\u003cli\u003eKelemen, P.B., McQueen, N., Wilcox, J., Renforth, P., Dipple, G., Vankeuren, A.P., 2020. Engineered carbon mineralization in ultramafic rocks for CO2 removal from air: review and new insights. Chem. Geol. 550, 119628. https://doi.org/10.1016/j.chemgeo.2020.119628.\u003c/li\u003e\n\u003cli\u003eKelland, M.E., Wade, P.W., Lewis, A.L., Taylor, L.L., Sarkar, B., Andrews, M.G., Lomas, M.R., Cotton, T.E.A., Kemp, S.J., James, R.H., 2020. Increased yield and CO\u003csub\u003e2\u003c/sub\u003e sequestration potential with the C4 cereal Sorghum bicolor cultivated in basaltic rock dust-amended agricultural soil. Glob. Chang. Biol. 26, 3658\u0026ndash;3676. https://doi.org/10.1111/gcb.15089.\u003c/li\u003e\n\u003cli\u003eLal, R., 2007. Carbon management in agricultural soils. Mitigation and Adaptation Strategies for Global Change 12, 303e322. https://doi.org/10.1007/s11027-006-9036-7.\u003c/li\u003e\n\u003cli\u003eLi, J., Hitch, M., Power, I.M., Pan, Y., 2018. Integrated mineral carbonation of ultramafic mine deposits\u0026mdash;A review. Minerals 8, 1\u0026ndash;18. https://doi.org/10.3390/min8040147.\u003c/li\u003e\n\u003cli\u003eLindsey, R., Dahlman, L., 2020. Climate change: Global temperature. https:// www.climate.gov/news-features/understanding-climate/climate-change-globaltemperature (Accessed 14/09/2023).\u003c/li\u003e\n\u003cli\u003eManning, D.A.C., Renforth, P., Lopez-Capel, E., Robertson, S., Ghazireh, N., 2013. Carbonate precipitation in artificial soils produced from basaltic quarry fines and composts: An opportunity for passive carbon sequestration. Int. J. Greenh. Gas Control 17, 309-317. https://doi.org/10.1016/j.ijggc.2013.05.012.\u003c/li\u003e\n\u003cli\u003eMillar, R., Fuglestvedt, J., Friedlingstein, P., Rogelj, J., Grubb, M.J., Matthews, H.D., Skeie, R.B., Forster, P.M., Frame, D.J., Allen, M.R., 2017. Emission budgets and pathways consistent with limiting warming to 1.5\u0026thinsp;\u0026deg;C. Nat. Geosci. 10, 741\u0026ndash;747. https://doi.org/10.1038/ngeo3031.\u003c/li\u003e\n\u003cli\u003ePang, Z., Tayyab, M., Kong, C., Hu, C., Zhu, Z., Wei, X., Yuan, Z., 2019. Liming positively modulates microbial community composition and function of sugarcane fields. Agronomy 9, 808 https://doi.org/doi.org/10.3390/agronomy9120808.\u003c/li\u003e\n\u003cli\u003eRahmanihanzaki, M., Hemmati, A., 2022. A review of mineral carbonation by alkaline solidwaste. Int. J. Greenh. Gas Control 121, 103798. https://doi.org/10.1016/j.ijggc.2022.103798.\u003c/li\u003e\n\u003cli\u003eRayment, G.E., Higginson, F.R., 1992. Australian laboratory handbook of soil and water chemical methods. Inkata Press Pty Ltd.\u003c/li\u003e\n\u003cli\u003eRenforth, P., Pogge von Strandmann, P.A.E., Henderson, G.M., 2015. The dissolution of olivine added to soil: Implications for enhanced weathering. Appl. Geochemistry 61, 109\u0026ndash;118. https://doi.org/10.1016/j.apgeochem.2015.05.016.\u003c/li\u003e\n\u003cli\u003eRuiz Sinoga, J.D., Pariente, S., Diaz, A.R., Martinez Murillo, J. F., 2012. Variability of relationships between soil organic carbon and some soil properties in Mediterranean rangelands under different climatic conditions (South of Spain). Catena 94, 17-25. https://doi.org/10.1016/j.catena.2011.06.004.\u003c/li\u003e\n\u003cli\u003eSanderman, J., 2018. Can management induced changes in the carbonate system drive soil carbon sequestration? A review with particular focus on Australia. Agric. Ecosyst. Environ. 155, 70-77. https://doi.org/10.1016/j.agee.2012.04.015.\u003c/li\u003e\n\u003cli\u003eStanbery, C., Ghahremani, Z., Huber, D.P., Will, R., Benner, S.G., Glenn, N., Hanif, T., Spaete, L., Terhaar, D., Lohse, K.A., Seyfried, M., Freutel, W., Pierce, J.L., 2023. Controls on the presence and storage of soil inorganic carbon in a semi-arid watershed. Catena 225, 106980. https://doi.org/10.1016/j.catena.2023.106980.\u003c/li\u003e\n\u003cli\u003ete Pas, E.E.E.M., Hagens, M., Comans, R.N.J., 2023. Assessment of the enhanced weathering potential of different silicate minerals to improve soil quality and sequester CO2. Front. Clim. 4, 954064 https://doi.org/10.3389/fclim.2022.954064.\u003c/li\u003e\n\u003cli\u003eWilson, S.A., Harrison, A.L., Dipple, G.M., Power, I.M., Barker, S.L.L., Ulrich Mayer, K., Fallon, S.J., Raudsepp, M., Southam, G., 2014. Offsetting of CO2 emissions by air capture in mine tailings at the Mount Keith Nickel Mine, Western Australia: rates, controls and prospects for carbon neutral mining. Int. J. Greenh. Gas Control 25, 121\u0026ndash;140. https://doi.org/10.1016/j.ijggc.2014.04.002.\u003c/li\u003e\n\u003cli\u003eZamanian, K., Pustovoytov, K., Kuzyakov, Y., 2016. Pedogenic carbonates: Forms and formation processes. Earth Sci. Rev. 157, 1-17. https://doi.org/10.1016/j.earscirev.2016.03.003.\u003c/li\u003e\n\u003cli\u003eZamanian, K., Zhou, J., Kuzyakov, Y., 2021. Soil carbonates: the unaccounted, irrecoverable carbon source. Geoderma 384, 114817. https://doi.org/10.1016/j.geoderma.2020.114817. \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"University of Guelph","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"enhanced rock weathering, soil inorganic carbon, pedogenic carbonate formation, carbon dioxide removal","lastPublishedDoi":"10.21203/rs.3.rs-3851689/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3851689/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eConsidered as a well-known carbon sequestration method, terrestrial enhanced rock weathering involves the application of crushed silicate-bearing minerals to urban and agricultural soils. Once dissolved in the soil-water system, alkaline minerals adjust the pH in a range favorable for pedogenic carbonate formation and, hence, atmospheric carbon drawdown. As a fast-weathering Ca-rich mineral, wollastonite is recognized as one of the primary candidates for this process. Although previous studies proved the potential of wollastonite to sequester carbon in croplands, no study has investigated the fate of wollastonite over the vertical profile of soil. Furthermore, no studies have investigated changes in the elemental composition of soils due to wollastonite amendment on a field scale. The present study presents the results of a multi-year sampling collection from different layers (0\u0026ndash;15, 15\u0026ndash;30, and 30\u0026ndash;60 cm) of agricultural soil amended with wollastonite in Woodstock, Ontario, Canada. The impact of initial soil pH on pedogenic carbonate formation was also investigated with the inclusion of two more field trials. The results denoted wollastonite addition increases the inorganic carbon pool of soil up to 6.60 t CO\u003csub\u003e2\u003c/sub\u003e/ha at higher (20 t/ha) wollastonite dosage. The elemental composition and mineralogy analyses were indicative of weathering occurrence in soil samples. This study indicates that carbonate formation is not limited to surficial layers, and deeper layers also need to be taken into account for estimating carbon capture due to ERW practice.\u003c/p\u003e","manuscriptTitle":"Tracking pedogenic carbonate formation and migration in agricultural soils amended with crushed wollastonite ore- Evidence from field trials","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-12 16:34:33","doi":"10.21203/rs.3.rs-3851689/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ac9758c8-f4ae-428e-9e87-ef375071be3f","owner":[],"postedDate":"January 12th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":28072842,"name":"Environmental Engineering"},{"id":28072843,"name":"Agronomy"},{"id":28072844,"name":"Geochemistry"}],"tags":[],"updatedAt":"2024-01-12T16:34:33+00:00","versionOfRecord":[],"versionCreatedAt":"2024-01-12 16:34:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3851689","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3851689","identity":"rs-3851689","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}