半干旱区退化草地开垦为苜蓿地对土壤无机碳的影响
Effects of the reclamation of degraded semi-arid grassland into alfalfa field on soil inorganic carbon
吴昊 1闻蕙钰 1高杨 2刘加彬1
作者信息
- 1. 西北农林科技大学水土保持科学与工程学院,陕西 杨凌 712100
- 2. 西北农林科技大学林学院,陕西 杨凌 712100
- 折叠
摘要
为分析半干旱区退化草地开垦后土壤无机碳储量的变化,探讨开垦对土壤无机碳的影响机制,以半干旱区开垦农田(苜蓿地)为研究对象,以邻近的退化草地(荒漠草原)作为对照,借助碳稳定同位素技术,测定并计算0～300 cm土壤深度土壤无机碳(SIC)、次生碳酸盐(PIC)和原生碳酸盐(LIC)的储量.结果表明,与退化草地相比,苜蓿地0～300 cm处的SIC总储量显著增加了88.42 Mg·hm-2,PIC总储量显著增加了105.71 Mg·hm-2,LIC总储量显著减少了17.29 Mg·hm-2.退化草地开垦促进了PIC在深层土壤的积累,进而促进了SIC的增加,表明开垦能够增强半干旱地区土壤的固碳能力,且PIC的增加导致了SIC的净累积.
Abstract
To explore the effects of the reclamation of degraded grassland on soil inorganic carbon(SIC)stocks and identify the mechanisms of SIC accumulation in a semi-arid region of China,we compared the SIC stock in a reclaimed farmland(alfalfa field),with that of an adjacent control site(degraded grassland desert).We used carbon stable isotope measurements to calculate the stock of SIC,pedogenic inorganic carbon(PIC),and lithogenic inorganic carbon(LIC)in 0-300 cm soil profiles at both sites.Our results showed that,in the alfalfa field soil,the total SIC and PIC were enriched by 88.42 and 105.71 Mg·hm-2,respectively,while the total LIC stock was depleted by 17.29 Mg·hm-2 compared with the degraded grassland.The reclamation of the degraded grassland promoted the accumulation of SIC,which was mainly caused by the accumulation of PIC in deep soil.Our findings indicate that,in semi-arid areas,reclamation can enhance the soil's carbon sequestration capacity,and that the net accumulation of SIC is mainly driven by the increase in PIC.
关键词
土壤无机碳/次生碳酸盐/原生碳酸盐/退化草地/开垦农田Key words
soil inorganic carbon/pedogenic inorganic carbon/lithogenic inorganic carbon/degraded grassland/reclaimed farmland引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据