Effectiveness of scarification for rehabilitating soil attributes affected by oilfield activities in norPatagonia, Argentina

The oil industry exerts substantial environmental pressure on drylands, posing a major threat to these fragile ecosystems. Specifically, the construction of drilling facilities disturbs approximately 0.6–1 ha around each borehole, where vegetation is removed, and the topsoil is replaced with a compacted layer of gravel and fine-textured materials. This process increases soil bulk density, disrupts soil aggregates, reduces porosity, aeration, and infiltration, and ultimately intensifies soil strength, runoff, and degradation. Scarification is commonly employed in Monte Austral (Argentina) to promote soil and vegetation recovery by enhancing water infiltration and root penetration, thereby improving soil structure and expediting ecosystem rehabilitation. To evaluate the effectiveness of scarification as a decompaction technique and its influence on rehabilitation, we assessed penetrometer resistance and unsaturated hydraulic conductivity under two conditions: (1) in natural, undisturbed areas, and (2) in scarified areas, categorized by the time elapsed since scarification: 8–13 years, 4–8 years, and less than 4 years. Our findings show that scarification reduces compaction within the 0–10 cm soil depth in the short term, but re-compaction and a hardened surface crust develop within eight years post-treatment. The results indicate that scarification alone is insufficient to trigger pedogenetic processes in compacted Technosols or to rehabilitate the ecosystem’s structural attributes.