نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 دانشگاه زنجان
2 گروه علوم خاک، دانشکده کشاورزی، دانشگاه زنجان
3 علوم و مهندسی خاک، دانشکده کشاورزی، دانشگاه زنجان، زنجان
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objective: The conversion of rangeland to agricultural land is a significant challenge in sustainable natural resource management, affecting soil productivity and physical quality. Many soil functions are closely related to soil physical quality, so accurately assessing and improving soil physical conditions is crucial for maintaining ecosystem functions in both rangeland and agricultural areas. This study aimed to evaluate the impact of rangeland conversion to agriculture on soil physical quality and identify the most influential physical soil properties affected by this land-use change in semi-arid areas of Zanjan province.
Materials and Methods: This research was conducted in three adjacent areas with different land-use histories, including rangeland areas, areas converted from rangeland to dryland farming less than 10 years ago, and areas converted over 30 years ago. Soil sampling was done from fifteen sites at two depths: 0-15 and 15-30 cm. Disturbed and undisturbed soil samples were collected from each depth, and various soil properties were measured using standard laboratory methods. Discriminant analysis was employed to identify the most important soil properties affected by land-use change.
Results: Land-use change significantly impacted total soil porosity, macroporosity, soil aeration capacity, soil hydraulic conductivity, structural stability index, soil compaction degree, organic carbon content, electrical conductivity, soil sodium content, and acid and hot water-extractable carbohydrates. A high correlation (r>0.6) was observed between total soil porosity, macroporosity, soil aeration capacity, soil structural index, and soil organic matter content. Acid and hot water-extractable carbohydrates significantly correlated with soil structural quality indicators, including structural stability index, soil porosity characteristics, and soil aggregation. Discriminant analysis results indicated that land-use change had the greatest impact on acid and hot water-extractable carbohydrates, soil aeration capacity, total porosity, and structural stability index. These properties were identified as the most important indicators for assessing the impact of land-use change on soil physical quality in the study area. Conversion from rangeland to agriculture reduced organic carbon content, degraded soil structure, decreased total and macroporosity, soil aeration capacity, and moisture retention and aggregation conditions.
Conclusion: The findings of this study indicated that the conversion of rangeland to agriculture adversely affected soil structural properties and reduced soil physical quality in the study area. Soil physical condition degradation due to land-use change was more severe in the short term (less than 10 years of cultivation), while long-term cultivation (more than 30 years) led to relative soil quality improvement in semi-arid areas. Implementing appropriate management practices in agricultural ecosystems can reduce soil degradation intensity due to land-use change in the long term. Additionally, assessing soil physical quality can provide a suitable tool for rapidly evaluating the impact of management practices on soil conditions in semi-arid areas.
کلیدواژهها [English]
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