Changes in soil organic carbon pools following long-term fertilization under a rain-fed cropping system in the Loess Plateau, China

作者：Ren-jie WANG, Jia-shan SONG, Yong-tao FENG, Jiang-xiang ZHOU, Junyu Xie, Asif Khan, Zongxian Che, Shu-lan ZHANG, Xueyun Yang · 发表于：Journal of Integrative Agriculture · 年份：2021 · DOI：10.1016/s2095-3119(20)63482-7 · 被引用次数：18 · 研究领域：Soil Carbon and Nitrogen Dynamics、Soil and Water Nutrient Dynamics、Soil and Unsaturated Flow

Understanding the mechanism of soil organic carbon (SOC) sequestration is of paramount importance in sustaining crop productivity and mitigating climate change. Long-term trials were employed to investigate the responses of total SOC and its pools, i.e., mineral-associated OC (MOC), particulate OC (POC, containing Light-POC and Heavy-POC), to fertilization regimes at Yangling (25-year), Tianshui (35-year) and Pingliang (37-year) under a rain-fed cropping system in the Loess Plateau. The fertilization regimes in each trial included three treatments, i.e., control (no nutrient input, CK), chemical fertilizers (CF), and organic manure plus chemical fertilizers (MCF). Relative to the CK, long-term fertilization appreciably increased SOC storage by 134, 89 and 129 kg ha−1 yr−1 under CF, and 418, 153 and 384 kg ha−1 yr−1 under MCF in plough layer soils (0–20 cm), respectively, at the Yangling, Tianshui and Pingliang sites. The MOC pools accounted for 72, 67 and 64% of the total SOC at the above three sites with sequestration rates of 76, 57 and 83 kg ha−1 yr−1 under CF and 238, 118 and 156 kg ha−1 yr−1 under MCF, respectively. Moreover, the MOC pool displayed a saturation behavior under MCF conditions. The POC accordingly constituted 27, 33 and 36% of SOC, of which Light-POC accounted for 11, 17 and 22% and Heavy-POC for 17, 16 and 15% of SOC, respectively. The sequestration rates of POC were 58, 32 and 46 kg ha−1 yr−1 under CF, and 181, 90 and 228 kg ha−1 yr−1 under MCF at the thr...