塔里木盆地北缘绿洲不同土地利用方式下土壤有机碳含量及其碳矿化特征  

Soil Organic Carbon Content and Carbon Mineralization Characteristics Under Different Land Use Types in Northern Tarim Basin

作　　者：李杨梅[1,2] 贡璐[1,2] 解丽娜[1,2] 

机构地区：[1]新疆大学资源与环境科学学院,新疆乌鲁木齐830046 [2]绿洲生态教育部重点实验室,新疆乌鲁木齐830046

出　　处：《水土保持通报》2017年第3期216-221,共6页Bulletin of Soil and Water Conservation

基　　金：新疆维吾尔自治区科技人才培养项目"自治区青年科技创新人才培养工程"(qn2015yx002);新疆维吾尔自治区教育厅办公室项目"基于稳定碳同位素技术的干旱区绿洲土壤碳库转化研究"(XJGRI2016023)

摘　　要：[目的]探讨土地利用方式对土壤有机碳含量及碳矿化的影响,为塔里木盆地北缘绿洲土壤生态系统的保护和恢复建设提供理论依据。[方法]基于野外采样和室内培养试验,分析土壤有机碳含量的基本特征,利用回归分析法拟合出土壤有机碳矿化动态变化过程。[结果]矿化累积释放的CO2含量大小依次为:果园>棉田>人工林>弃耕地>荒草地>盐碱地>沙地。不同土地利用方式土壤有机碳矿化反应趋势相同,1~6d为快速分解阶段,日均矿化量高但反应时间短,6~28d为缓慢分解阶段,动态变化与前者相反。有机碳矿化率大小依次为:沙地>荒草地>盐碱地>弃耕地>人工林>棉田>果园,沙地最高,达(10.36±0.24)%,表明沙地土壤有机碳稳定性最差,而果园具有较强的固定有机碳能力。[结论]土地利用方式对土壤有机碳矿化及其固碳能力均有显著影响。[Objective] Illustrating the effects of land use change on soil organic carbon（SOC） content and SOC mineralization, to provide theoretical basis for soil ecosystem preservation and restoration of oasis in the northern marginal zones of the Tarim Basin.[Methods] Based on field sampling and laboratory incubation experiment, the basic characteristics of SOC content were analyzed. Regression analysis was used to investigate the dynamic change process of SOC mineralization.[Results] The accumulative amounts of SOC mineralization of different land use types ranked as：orchard 〉 cotton 〉 artificial forest 〉 abandoned farmland 〉 barren grassland 〉 saline-alkali land 〉 sandy soil. The chronical trends of SOC mineralization of different land use types were almost the same during the cultivation period. The daily SOC mineralization rate involved two stages of fast（1 to 6 d） and slow （6 to 28 d） decomposition. The former stage had shorter duration and more daily decomposition quantity; while the latter was opposite. Organic carbon mineralization rates tended to decrease in the order：sandy soil 〉 barren grassland 〉 saline-alkali land 〉 abandoned farmland 〉 artificial forest 〉 cotton 〉 orchard. The rates of organic carbon mineralization were the highest in sandy soils, about （10.36±0.24）%. It indicated that sandy soil had the lowest stability of the soil organic carbon, while carbon sequestration ability of orchard was higher as compared to those of other land use types.[Conclusion] Both of SOC mineralization and carbon sequestration ability could be obviously influenced by different land use types.

关 键 词：塔里木盆地 土地利用方式 土壤有机碳含量 有机碳矿化 

分 类 号：S153.621[农业科学—土壤学]