Long-term effects of conventional cultivation on soil cation exchange capacity and base saturation in an arid desert region

• Published in: The Science of the total environment 2024-11, Vol.949, p.175075, Article 175075
• Main Authors: Ma, Dengke, He, Zhibin, Zhao, Wenzhi, Li, Rui, Sun, Weihao, Wang, Wen, Lin, Pengfei, Wei, Lemin, Ju, Wenliang
• Format: Article
• Language: English
• Subjects: agricultural land; Arid oasis region; arid zones; Base saturation; cation exchange capacity; chronosequences; Conventional tillage; Desert reclamation; environment; evolution; Exchangeable bases; oases; particle size; regression analysis; silt fraction; soil fertility; soil organic matter; soil quality; soil water content; sustainable agriculture; total nitrogen
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.175075

Land reclamation and subsequent management affect soil condition, which is critical for sustainable agricultural production. Soil cation exchange capacity (CEC) and base saturation (BS%) play an important role in the assessment of soil fertility and buffering capacity. However, the variation of these indicators in the evolution of oasis farmland in arid desert areas remains unclear. Therefore, this study was carried out aiming to evaluate the effect of desert reclamation and following long-term conventional cultivation on the CEC and BS%. For the study, we investigated the CEC and exchangeable bases (ExBas) content in oasis farmlands along a chronosequence (0–100 years) of cultivation in arid region and identified the key factors affecting CEC and BS%. The results showed that soil CEC and ExBas significantly increased after desert reclamation, whereas the BS% dramatically decreased. However, all these changes were alleviated with the conventional cultivation age. Regression analysis showed that soil CEC, ExBas, and BS% all exponentially changed with cultivation years. Based on our findings, CEC and ExBas were closely related to soil particle size composition, total nitrogen (TN), soil organic matter (SOM) and soil water content (SWC). The multiple stepwise regression further indicated that the changes in CEC and ExBas after reclamation mainly depended on the silt content, SWC, SOM, and TN. Our findings highlight that although desert reclamation increases soil CEC and ExBas in arid area, this effect tends to disappear after about 100 years of conventional cultivation, and meanwhile, the decline in BS% due to increased acids should also be noted. [Display omitted] •Desert reclamation increases soil CEC and ExBas, whereas it decreases BS%.•The CEC, ExBas, and BS% exponentially changes with conventional farming years.•The CEC and ExBas are closely related to SOM, SWC, and silt content.•Soil basic physicochemical properties explain >80 % of CEC variation.