Changes in soil organic carbon and nitrogen after 26 years of farmland management on the Loess Plateau of China

作     者：ZHOU Zhengchao ZHANG Xiaoyan GAN Zhuoting 

作者机构：Department of Tourism and Environmental Sciences Shaanxi Normal University Key Laboratory of Disaster Survey and Mechanism Simulation of Shaanxi Province Baoji University of Arts and Sciences 

出 版 物：《Journal of Arid Land》 (干旱区科学（英文版）)

年 卷 期：2015年第7卷第6期

页      面：806-813页

核心收录：

学科分类：09[农学] 0903[农学-农业资源与环境] 090301[农学-土壤学] 

基　　金：funded by the Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China (131025) the Natural Science Foundation of Shaanxi Province (2014KJXX-52) 

主　　题：soil organic carbon(SOC) soil N fertilizer land use change semi arid area 

摘      要：Soil carbon（C） and nitrogen（N） play a crucial role in determining the soil and environmental quality. In this study, we investigated the effects of 26 years（from 1984 to 2010） of farmland management on soil organic carbon（SOC） and soil N in abandoned, wheat（Triticum aestivum L.） non-fertilized, wheat fertilized（mineral fertilizer and organic manure） and alfalfa（Medicago Sativa L.） non-fertilized treatments in a semi-arid region of the Loess Plateau, China. Our results showed that SOC and soil total N contents in the 0–20 cm soil layer increased by 4.29（24.4%） and 1.39 Mg/hm2（100%）, respectively, after the conversion of farmland to alfalfa land. Compared to the wheat non-fertilized treatment, SOC and soil total N contents in the 0–20 cm soil layer increased by 4.64（26.4%） and 1.18 Mg/hm2（85.5%）, respectively, in the wheat fertilized treatment. In addition, we found that the extents of changes in SOC, soil total N and mineral N depended on soil depth were greater in the upper soil layer（0–30 cm） than in the deeper soil layer（30–100 cm） in the alfalfa land or fertilizer-applied wheat land. Fertilizer applied to winter wheat could increase the accumulation rates of SOC and soil total N. SOC concentration had a significant positive correlation with soil total N concentration. Therefore, this study suggested that farmland management, e.g. the conversion of farmland to alfalfa forage land and fertilizer application, could promote the sequestrations of C and N in soils in semi-arid regions.