Effects of land use on soil organic and inorganic C and N at Cs-137 traced erosional and depositional sites in mountain agroecosystems

摘要

Patterns of erosion, transport and deposition of soil particles not only affect the distribution of mineral fraction of the soil but their organic components. The spatial variability of soil nutrients in Mediterranean mountain agroecosystems that combine complex land uses and abrupt topography is poorly documented despite emerging concerns on nutrients fate require understanding the potential impact of soil erosion on nutrients redistribution across landscapes. This study aims to assess at catchment scale the spatial patterns of soil organic and inorganic carbon (SOC, SIC), soil organic carbon fractions and total nitrogen (TN) in relation to land uses and soil redistribution. To this purpose we selected a well characterized endorheic catchment located in NE Spain where soil erosion and deposition rates derived from Cs-137 measurements were previously documented and we mapped the distribution of cropland and rangeland areas. A grid of 100 x 100 m was established for collecting a total of 205 soil samples for nutrients and standard soil analyses.