Macroinvertebrate-Based Bioassessment of Water Quality and Ecological Integrity in the Kankai River, Eastern Nepal

Macroinvertebrate-Based Bioassessment of Water Quality and Ecological Integrity in the Kankai River, Eastern Nepal | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL This is a preprint and has not been peer reviewed. Data may be preliminary. 5 November 2025 V1 Latest version Share on Macroinvertebrate-Based Bioassessment of Water Quality and Ecological Integrity in the Kankai River, Eastern Nepal Authors : Jeevan Gurung 0000-0001-8784-4617 [email protected] , Debashri Mondal , and Jash Limbu 0000-0002-8006-4199 Authors Info & Affiliations https://doi.org/10.22541/au.176233051.17790584/v1 275 views 128 downloads Contents Abstract 2.1 Study area 2.2 Physicochemical measurements 2.3 Macroinvertebrate sampling and identification 2.4 Biotic and diversity indices 2.5 Statistical analyses 3. Results 3.2 Macroinvertebrate composition and diversity 3.3 Multivariate patterns 4 Discussion 6. Conclusin Supplementary Material Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract Benthic macroinvertebrates serve as key indicators of freshwater ecosystem health due to their varied tolerance to environmental stressors. This study assessed spatial and seasonal variation in macroinvertebrate assemblages and water quality along the Kankai River, eastern Nepal. Thirty taxa belonging to 21 families were identified, with Arthropoda predominating. Sensitive Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa characterized well-oxygenated upstream sites, whereas pollution-tolerant oligochaetes, chironomids, and gastropods dominated nutrient-enriched downstream reaches. Diversity indices, Biological Monitoring Working Party (BMWP) scores, and Hilsenhoff Biotic Index (HBI) values captured clear pollution gradients. Canonical Correspondence Analysis (CCA) revealed that phosphate, free CO₂, pH, and dissolved oxygen (DO) exerted the strongest influence on community structure, separating sensitive and tolerant assemblages along oxygenation and nutrient axes. Cluster analysis distinguished EPT assemblages from intermediate (molluscs, crustaceans) and tolerant (oligochaetes, chironomids) groups. These patterns demonstrate that macroinvertebrate tolerance metrics effectively integrate physicochemical variability and ecological processes, providing a robust tool for biomonitoring and management. The study contributes region-specific insight into Himalayan-Terai river ecology and highlights the need for pollution control and conservation measures to sustain freshwater biodiversity under increasing anthropogenic pressures. 1. Introduction Freshwater ecosystems support a disproportionate share of global biodiversity relative to their area and provide vital services including nutrient cycling, fisheries, drinking water, and cultural values. However, they face accelerating pressures from land-use change, hydrological alteration, pollution, invasive species, and climate extremes (Allan 2004; Dudgeon et al. 2006). Traditional monitoring based solely on physicochemical parameters offers only a snapshot and often fails to capture cumulative ecological responses. Consequently, macroinvertebrate-based bioassessment has become central to evaluating ecological integrity because benthic assemblages integrate conditions over time and respond predictably to gradients in oxygen, nutrients, organic enrichment, and habitat quality (Rosenberg and Resh 1993; Barbour et al. 1999; Bonada et al. 2006). In South Asia, and particularly Nepal, rapid urbanization and agricultural intensification have intensified nutrient loading and organic pollution in rivers, yet long-term biological monitoring remains limited (WWF 2022; BEPLS 2023). Nepal’s Himalayan-Terai rivers are monsoon-dominated and traverse steep ecological gradients, making them ideal natural laboratories for studying community responses to multiple stressors. Within this context, the Kankai River is ecologically and socio‑economically important, supporting irrigation, fisheries, religious practices, and domestic supply, but faces increasing pressures from settlements, sand mining, agricultural runoff, and ritual activities. Here we conduct an integrated bioassessment of the Kankai River using macroinvertebrate assemblages and supporting physicochemical data collected at six stations across 12 months. We hypothesized that (i) oxygen-rich upstream reaches would support sensitive EPT taxa, while nutrient‑enriched downstream sections would be dominated by tolerant oligochaetes and chironomids; and (ii) nutrient enrichment and oxygen dynamics would be the principal axes structuring community turnover revealed by multivariate ordination. Our objectives were to quantify spatial and seasonal variation in water quality; characterize macroinvertebrate composition, diversity, and tolerance; evaluate taxa-environment relationships using CCA and clustering; and identify robust ecological indicators for river management in Nepal. 2. Materials and Methods 2.1 Study area The Kankai River originates in the Sandakpur highlands of eastern Nepal and flows through Ilam and Jhapa districts before joining the Mahananda River in India. The basin (~1,550 km²) spans mountain, hill, and Terai plains, creating pronounced altitudinal and climatic gradients. Six sampling stations (S1-S6) were selected to represent longitudinal and disturbance gradients from minimally impacted headwaters to intensively farmed lowlands. S1 (Mahamai) served as the reference site; S2 (Danawari) is influenced by settlements and nearby hydropower; S3 (Domukha) lies in the foothills with moderate pressures; S4 (Kankai Ghat) is a pilgrimage site with ritual activities and organic inputs; S5 (Shivaganj) is semi‑urban with agrochemical runoff; and S6 (Gauriganj) lies in densely settled Terai plains. Figure 1. Map of sampling stations (S1-S6) along the Kankai River 2.2 Physicochemical measurements Monthly sampling from July 2024 to June 2025 was conducted between 12:00 and 14:00 to minimize diel variability following APHA (2012) protocols. In situ measurements included water temperature (°C), pH, dissolved oxygen (mg L⁻¹), electrical conductivity (µS cm⁻¹), turbidity (NTU), and water velocity (m s⁻¹). Laboratory analyses (Batabaraniya Sewa Kendra, Biratnagar) quantified alkalinity and hardness (mg L⁻¹ as CaCO₃), free CO₂ (mg L⁻¹), BOD₅ (mg L⁻¹), nutrients (NO₃⁻‑N, NO₂⁻‑N, NH₄⁺‑N, PO₄‑P), and chloride using standard titrimetric and spectrophotometric methods. 2.3 Macroinvertebrate sampling and identification Macroinvertebrates were collected using a 500‑µm mesh dip‑net with a multihabitat approach (riffles, pools, vegetated margins). Five subsamples per station were pooled, sieved, and preserved in 5% formalin. Specimens were sorted under a stereomicroscope and identified to the lowest practicable taxon (typically genus) using regional keys (Baker 1928; Pennak 1953; Morse et al. 1994; Merritt and Cummins 1996). 2.4 Biotic and diversity indices Community structure and tolerance metrics were assessed using Shannon–Wiener diversity (H′), Simpson’s diversity (D), Margalef’s richness (R), Pielou’s evenness (J), dominance (Y), Biological Monitoring Working Party (BMWP) score and Average Score Per Taxon (ASPT), and the Hilsenhoff Biotic Index (HBI). HBI classes followed conventional thresholds: 8.5 very poor. 2.5 Statistical analyses Species data were log₁₀(x+1) transformed. Canonical Correspondence Analysis (CCA) evaluated taxa–environment relationships; model significance was tested via permutation (999 runs). Bray–Curtis similarity with UPGMA clustering classified stations by assemblage composition. Where appropriate, permutation‑based ANOVA examined significance of environmental effects on assemblage structure. Analyses were conducted in R (vegan, stats, BiodiversityR). 3. Results 3.1 Physicochemical gradients Station‑wise means revealed downstream increases in BOD, ammonium, phosphate, and turbidity, with comparatively high DO in headwaters. Free CO₂ peaked at midstream sites, indicating localized hotspots (Table 1). Table 1. Station‑wise physicochemical parameters (means ± SD) Parameter S1 S2 S3 S4 S5 S6 Mean SD CPCB Standard WHO Standard W.T. 23.26 23.47 23.64 23.81 23.97 24.14 23.71 0.32 - - pH 7.21 7.35 7.41 7.42 7.28 6.97 7.27 0.16 6.5-9 6.5-9 W.V. 1.46 1.31 1.15 1.07 0.89 0.76 1.11 0.25 - - Turbidity 2.15 2.54 2.84 3.17 3.32 3.35 2.89 0.47 5 10-25 E.C. 194.58 197.25 198.83 204.33 202.33 203.25 200.09 3.82 <500 150-500 D.O. 7.07 7.13 7.18 7.27 7.19 7.04 7.14 0.08 6 6-8 fCO2 8.55 8.67 17.22 26.45 8.55 8.86 13.05 7.40 10 <5 Alkalinity 136.83 109.17 97.0 97.67 58.25 49.17 91.34 32.65 200-600 20-200 Hardness 86.58 80.08 73.33 80.83 69.33 65.67 75.97 7.87 200-600 50-200 Chloride 5.83 7.25 8.25 9.0 9.58 8.67 8.09 1.35 250 <230 BOD 11.58 12.58 12.75 12.33 14.08 13.92 12.87 0.96 <3 <3 NO3-N 0.04 0.05 0.04 0.04 0.04 0.04 0.04 0.004 50 <10 NO2-N 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.0 3 <0.06 NH4-N 0.05 0.06 0.07 0.09 0.09 0.1 0.07 0.02 0.5 <0.05 PO4-P 0.04 0.06 0.07 0.07 0.06 0.06 0.06 0.01 0.1 <0.05 Seasonally, monsoon months showed elevated turbidity and BOD, whereas winter exhibited higher DO; late pre‑monsoon indicated rising BOD and reduced dilution. These patterns are consistent with cumulative inputs from settlements and agriculture along the river corridor (Table 2). Table 2 . Month‑wise physicochemical parameters (means ± SD) Parameter Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Mean SD WHO CPCB W.T. 27.7 28.45 24.77 24.36 18.31 17.31 14.43 20.6 24.73 26.31 27.95 28.38 23.61 4.8 - - pH 7.37 7.16 7.21 7.32 7.1 6.98 7.1 7.15 7.11 7.18 7.21 7.38 7.19 0.12 6.5-9 6.5-9 W.V. 1.27 1.37 1.17 1.14 1.1 1.06 0.95 0.72 0.83 0.75 1.15 1.33 1.07 0.22 - - Turbidity 5.61 6.35 3.99 2.39 2.44 1.67 1.41 1.68 1.07 2.38 2.79 3.81 2.96 1.67 10-25 5 E.C. 215.42 218.17 208.92 202.75 200.08 194.42 188.5 188.17 183.33 181.42 194.75 208.92 198.74 12.32 150-500 <500 D.O. 6.48 6.84 7.3 7.59 7.64 7.54 8.21 7.43 6.89 6.18 5.67 6.53 7.02 0.72 6-8 6 fCO 2 12.23 12.72 12.75 13.65 12.43 135.68 12.65 12.03 12.95 11.4 12.73 13.16 22.86 35.53 <5 10 Alkalinity 93.33 90.42 91.42 90.25 92.92 90.92 91 88.92 91.33 89.92 93.08 90.75 91.19 1.34 20-200 200-600 Hardness 84.67 66.17 59.75 45.83 64.17 76.58 82.42 92.5 96.42 77.42 77.33 78.42 75.14 14.2 50-200 200-600 Chloride 10.17 9.08 8.5 6.83 6.08 4.58 5.17 6.25 7.08 8.17 8.92 9.58 7.53 1.8 <230 250 BOD 16.42 15.17 10 8.83 7.5 7.17 7.08 8.25 11.42 14.25 16.33 23.17 12.13 4.99 <3 <3 NO3-N 0.05 0.05 0.04 0.02 0.03 0.03 0.03 0.03 0.03 0.02 0.03 0.06 0.03 0.01 <10 50 NO2-N 0.04 0.04 0.04 0.03 0.02 0.03 0.02 0.02 0.02 0.03 0.02 0.04 0.03 0.008 <0.06 3 NH4-N 0.0533 0.0483 0.0375 0.0533 0.07 0.0792 0.1175 0.1008 0.0925 0.0825 0.0642 0.0742 0.0728 0.0233 <0.05 0.5 PO4-P 0.07 0.06 0.05 0.05 0.03 0.03 0.04 0.04 0.05 0.05 0.04 0.05 0.05 0.01 <0.05 0.1 3.2 Macroinvertebrate composition and diversity Thirty taxa from six classes and 21 families were recorded. Arthropoda dominated overall abundance, followed by Mollusca and Annelida (Figure 2). Figure 2. Macroinvertebrate community structure across stations Upstream sites were characterized by EPT taxa ( Baetis , Ephemerella , Neoperla , Amphinemura , Hydropsyche , and Chimarra. ), while downstream reaches were dominated by tolerant Chironomus, Tubifex, Limnodrilus, and Physa (Table 3). Table 3. Macroinvertebrate taxa, tolerance values (BMWP/HBI), and conservation information. Phylum Class Family Code Species IUCN Red List PTV / BMWP HBI (0-10) Arthropoda Crustacea Palaemonidae C1 Macrobrachium lamarrei LC 5 5 Arthropoda Crustacea Palaemonidae C2 Macrobrachium altifrons LC 5 5 Arthropoda Crustacea Gecarcinucidae C3 Barytelphusa lugubris NE 6 6 Arthropoda Crustacea Potamidae C4 Himalayapotamon atkinsonianum NE 6 6 Arthropoda Crustacea Gecarcinucidae C5 Lobothelphusa woodmasoni NE 6 6 Arthropoda Crustacea Potamidae C6 Acanthopotamon martensi NE 6 6 Arthropoda Crustacea Potamidae C7 Liotelphus gogei NE 6 6 Arthropoda Crustacea Potamidae C8 Acanthopotamon fungosum NE 6 6 Arthropoda Crustacea Gecarcinucidae C9 Paratelphusa spinigera NE 6 6 Arthropoda Insecta Nepidae C10 Nepa cinerea NE 4 7 Arthropoda Insecta Nepidae C11 Ranatra linearis NE 4 7 Arthropoda Insecta Trogiidae C12 Trogium pulsatorium NE 2 8 Arthropoda Insecta Gomphidae C13 Anisogomphus bivittatus LC 8 4 Arthropoda Insecta Baetidae C14 Baetis spp. NE 10 4 Arthropoda Insecta Heptageniidae C15 Ephemerella spp. NE 10 3 Arthropoda Insecta Perlidae C16 Neoperla spp. NE 10 2 Arthropoda Insecta Nemouridae C17 Amphinemura spp. NE 10 2 Arthropoda Insecta Hydropsychidae C18 Hydropsyche spp. NE 8 4 Arthropoda Insecta Philopotamidae C19 Chimarra spp. NE 10 3 Arthropoda Insecta Chironomidae C20 Chironomus spp. NE 2 8 Mollusca Gastropoda Viviparidae C21 Bellamya bengalensis LC 3 7 Mollusca Gastropoda Lymnaeidae C22 Lymnaea acuminata LC 3 7 Mollusca Gastropoda Ampullariidae C23 Pila globosa LC 3 6 Mollusca Gastropoda Thiaridae C24 Thiara tuberculata LC 3 6 Mollusca Gastropoda Physidae C25 Physa spp. NE 2 8 Mollusca Bivalvia Unionidae C26 Parreysia caerulea LC 4 6 Mollusca Bivalvia Unionidae C27 Lamellidens marginalis LC 4 6 Annelida Hirudinea Hirudinidae C28 Hirudinaria granulosa NE 3 7 Annelida Clitellata Naididae C29 Tubifex spp. NE 1 10 Annelida Clitellata Naididae C30 Limnodrilus spp. NE 1 10 Diversity indices indicated moderate to high heterogeneity (Shannon 2.45–2.96; Simpson 0.90–0.94), with richness peaking downstream despite organic stress (Table 4). Table 4. Diversity indices (Shannon, Simpson, richness, evenness, dominance, Margalef) by station Station Shannon Simpson Richness Evenness Dominance Margalef St.1 2.60 0.92 15.00 0.96 0.08 4.16 St.2 2.65 0.92 18.00 0.92 0.08 4.44 St.3 2.45 0.90 14.00 0.93 0.10 3.24 St.4 2.59 0.92 15.00 0.96 0.08 3.19 St.5 2.92 0.94 22.00 0.95 0.06 4.36 St.6 2.96 0.94 22.00 0.96 0.06 4.01 3.3 Multivariate patterns Clustering distinguished three ecological groups along a tolerance gradient: (i) sensitive EPT assemblages in oxygen‑rich upstream habitats, (ii) tolerant oligochaetes and chironomids in organically enriched reaches, and (iii) intermediate molluscs and crustaceans (Figure 3). Figure 3 . Cluster dendrogram of macroinvertebrate taxa along the tolerance gradient CCA identified phosphate, free CO₂, pH, and DO as principal drivers of community turnover, separating sensitive from tolerant assemblages along nutrient and oxygen axes (Figure 4). Figure 4 . Canonical Correspondence Analysis (CCA) biplot showing taxa–environment relationship 4 Discussion This study demonstrates that spatial variation in physicochemical parameters strongly influenced macroinvertebrate distribution in the Kankai River. Longitudinal gradients were evident: upstream reaches retained high dissolved oxygen and low organic loading, while downstream sections were characterized by elevated BOD, ammonium, phosphate, and turbidity. These patterns reflect cumulative effects of natural processes and anthropogenic stressors, especially agriculture and settlement discharges. Comparable downstream deterioration has been documented in South Asian rivers, including the Bagmati (Baniya et al. 2019), Koshi (Doody 2016), and Ganges tributaries (Sharma and Behera 2022). Macroinvertebrate assemblages tracked these gradients predictably. Sensitive EPT taxa dominated oxygen‑rich upstream sites, while Chironomidae, Tubificidae, and Physidae proliferated in organically enriched downstream habitats. This conforms to global evidence of EPT sensitivity (Lenat 1993; Buss et al. 2015) and oligochaete/chironomid tolerance (Verdonschot 2006). Similar upstream‑downstream replacements have been reported in Himalayan foothill rivers (Suren 1994; Semwal and Mishra 2011), Ethiopian highlands (Gezie et al. 2017), and South American rivers (Boyero et al. 2006). Diversity indices revealed moderate to high heterogeneity, with Shannon values (2.45–2.96) and Simpson values (0.90–0.94) comparable to Nepalese mid‑hill rivers (Rai et al. 2019) and moderately impacted Asian streams (Li et al. 2012). Evenness remained high across sites, indicating relatively balanced communities despite localized dominance of tolerant taxa. Interestingly, richness and diversity peaked at S5–S6, consistent with the intermediate disturbance hypothesis (Connell 1978), where moderate stress increases habitat heterogeneity and supports higher richness. This has also been observed in tropical rivers (Bispo and Oliveira 2007). Multivariate analyses clarified community structuring. Cluster analysis separated three groups: (i) EPT species in high‑quality upstream habitats, (ii) oligochaetes and chironomids under nutrient enrichment, and (iii) molluscs and crustaceans with intermediate tolerance. This tripartite structure reflects functional niche partitioning, consistent with European rivers (Verdonschot 2006) and Indian Himalayan streams (Sivaramakrishnan et al. 1995). The grouping of molluscs and crustaceans as intermediates suggests their utility as supplementary bioindicators, echoing findings from Chinese subtropical streams (Li et al. 2019). The CCA ordination confirmed that DO, BOD, turbidity, and nutrients were the dominant drivers of tolerant taxa, while dissolved oxygen, velocity, alkalinity, and hardness structured EPT distributions. Similar axes of community separation have been reported in the Ganges basin (Nautiyal et al. 2004), Ethiopian highlands (Mengist et al. 2020), and Brazilian streams (Baptista et al. 2001). Importantly, our findings demonstrate that even within a relatively short river segment, subtle chemical gradients can produce pronounced turnover in assemblages. Comparisons reveal both convergence and divergence with global studies. Convergence lies in the universal diagnostic value of EPT versus oligochaete/chironomid assemblages. Divergence appears in the high downstream richness despite organic stress, likely reflecting seasonal flushing, habitat heterogeneity, and colonization by tolerant taxa- a pattern also noted in the Bagmati (Baniya et al. 2019) and Mekong (Dudgeon 2010). Another distinction is the role of crustaceans (Macrobrachium, Potamidae crabs), which clustered as intermediate taxa. While rarely emphasized in temperate protocols, these groups may hold particular diagnostic relevance in tropical and subtropical Asia. The implications for biomonitoring and management are significant. Macroinvertebrates provide cost‑effective ecological indicators in Nepalese rivers, with EPT richness and tolerance metrics forming the foundation. Incorporating molluscs and crustaceans could enhance region‑specific indices. This influence of free CO₂, pH, DO, BOD, turbidity, and nutrients highlights the need for improved control of agricultural runoff and wastewater discharges, a recommendation consistent with other Himalayan and Southeast Asian studies (Bhandari et al. 2019). In conclusion, this study confirms both the global applicability and local adaptation of macroinvertebrate‑based bioassessment. While broad indicator groups remain consistent worldwide, regional taxa such as freshwater prawns and Himalayan crabs add diagnostic value. Integrating these into monitoring frameworks can strengthen ecological sensitivity and management relevance. From a conservation perspective, the clear separation of sensitive and tolerant taxa underscores the urgency of pollution control, habitat restoration, and continuous biomonitoring to sustain river health in Nepal and beyond. 5 Ecological Significance The integration of macroinvertebrate community structure with physicochemical gradients in the Kankai River provides a process‑based understanding of how biodiversity responds to multiple stressors in monsoon‑driven Himalayan systems. These results extend ecological theory by supporting longitudinal succession and the intermediate‑disturbance framework within tropical rivers. The clear partitioning of sensitive and tolerant taxa along oxygen and nutrient axes underscores adaptive strategies that reflect both evolutionary heritage and ecological filtering. Importantly, the functional role of region‑specific groups such as freshwater prawns and crabs broadens current biomonitoring paradigms that have been developed largely from temperate systems. Thus, this study not only fills a geographic gap but also contributes to global perspectives on tropical river ecology, community adaptation, and ecosystem resilience under intensifying anthropogenic pressure. 6. Conclusin This study delivers the first integrated macroinvertebrate‑based bioassessment of the Kankai River, eastern Nepal. Upstream sites supported oxygen‑rich EPT assemblages, whereas downstream reaches were dominated by tolerant taxa under nutrient and organic enrichment. Canonical and cluster analyses confirmed that phosphate, free CO₂, pH, and DO are key drivers of community turnover. The findings validate macroinvertebrates as reliable indicators of ecological integrity and emphasize the need for improved wastewater management and agricultural practices. Incorporating regionally important crustaceans and molluscs into existing indices will enhance local diagnostic accuracy. The study provides a scientific foundation for biomonitoring, conservation, and adaptive river‑basin management across the Himalayan–Terai region. Data Availability Statement All data supporting the findings of this study are included within the article and its supplementary materials. No additional datasets were generated or analyzed during the current study. Funding This research received no external funding. Author contributions Jeevan Kumar Gurung: Conceptualization, Formal analysis, Investigation, Writing-original draft; Jash Hang Limbu: Methodology, Software, Data curation; Debashri Mondal: Supervision, Visualization. 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WHO Handbook on Indoor Radon: A Public Health Perspective. World Health Organization Press, Geneva. WWF. 2022. Integrated River Health Assessment of the Narayani River, Nepal. World Wide Fund for Nature, Nepal. Supplementary Material File (all figures.docx) Download 643.90 KB File (tables.docx) Download 29.56 KB Information & Authors Information Version history V1 Version 1 05 November 2025 Copyright This work is licensed under a Non Exclusive No Reuse License. Keywords community ecology description ecosystem freshwater invertebrate Authors Affiliations Jeevan Gurung 0000-0001-8784-4617 [email protected] Tribhuvan University - Damak Multiple Campus View all articles by this author Debashri Mondal Raiganj University View all articles by this author Jash Limbu 0000-0002-8006-4199 Shanghai Ocean University View all articles by this author Metrics & Citations Metrics Article Usage 275 views 128 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Jeevan Gurung, Debashri Mondal, Jash Limbu. Macroinvertebrate-Based Bioassessment of Water Quality and Ecological Integrity in the Kankai River, Eastern Nepal. Authorea . 05 November 2025. DOI: https://doi.org/10.22541/au.176233051.17790584/v1 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. 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