草业学报2017，Vol.26Issue(8)：35-42,8.DOI:10.11686/cyxb2016440
宁夏荒漠草原自然恢复演替过程中土壤有机碳及其分布的变化
Variations in soil organic carbon content and distribution during natural restoration succession on the desert steppe in Ningxia
摘要
Abstract
Fencing enclosure) is one of the strategies used to promote the natural restoration of ecological communities on the desert steppe in Ningxia.To explore the effects of enclosure on soil organic carbon and its distribution,field studies were conducted at sites with 3,5,7,and 10 years of enclosure.Soil samples were collected to determine the total organic carbon concentration and its distribution at different soil depths and in soil aggregates.The results showed that the soil organic carbon concentrations were higher in 7-year and 10-year enclosed grasslands than in those enclosed for shorter times,except at 0-5 cm depth.The concentrations of soil organic carbon were lower in the 0-5 cm and 5-10 cm soil layers than in the 10-20 cm and 20-40 cm soil layers.The soil organic carbon concentrations in soil aggregate particles at 0-10 cm depth were highest in the 3-year enclosed grassland,while those at 10-40 cm depth increased with longer enclosure times.The maximum soil organic carbon contents were in aggregates with 1-0.5 mm and 0.5-0.25 mm diameters.Aggregates of ＜0.25 mm,＞5 mm or ＜0.25 mm,and ＞5 mm made the largest contributions to soil organic carbon content at 0-10 cm depth,10-20 cm depth and 20-40 cm depth,respectively.The contribution of aggregates to soil organic carbon content decreased with increasing enclosure times.As the soil depth increased,the contribution of aggregates to soil organic carbon content decreased,but the contributions of macroaggregates to soil organic carbon content increased.In conclusion,enclosure was beneficial for carbon sequestration.The restoration of the ecosystem on the degraded desert steppe appeared to undergo a transition at the 7th year of enclosure.关键词
荒漠草原/恢复演替/土壤有机碳/分布Key words
desert steppe/restoration succession/soil organic carbon/distribution引用本文复制引用
许冬梅,许新忠,王国会,陶利波..宁夏荒漠草原自然恢复演替过程中土壤有机碳及其分布的变化[J].草业学报,2017,26(8):35-42,8.基金项目
国家自然科学基金(31460624)和宁夏大学草学一流学科建设项目资助. （31460624）
