Effects of agro-activities on the soil organic carbon and soil properties in the middle reaches of Heihe river, Northwestern China

Knowledge about changes of SOC and other properties under influence of human activities in arid zone is very important for local cropland persistent management. In our study, SOC and selected soil properties had been investigated in the Linze country located in Hexi corridor, northern west China. The GIS tool was used to explain the causes resulted in SOC spatial distribution. The results indicated that the highest levels of SOC, humic acid, and fulvic acid presented in early cultivated plots, then in lately reclaimed cropland, and the lowest in desert soil. The remarkable increasing of soil CEC and clay content can been seen in arable land in contrast to desert land. Our findings may suggest that agricultural practices, such as irrigation, use of manure and fertilizer, return of crop residues, etc. protect SOC from loss and improve the soil fertility in arid area studied.