湿地土壤有机碳及其活性组分分布特征影响因素研究

红碱淖湖泊湿地是西北半干旱荒漠区重要的生态屏障,随着湖泊面积的减少以及土壤退化程度的加剧,逐渐形成5种典型的景观类型(盐碱沼泽、沼泽化草甸、草地、草原化沙地、沙地)。基于野外实地调查,选取红碱淖湖泊湿地流域蟒盖兔和尔林兔2个典型子流域,研究湖泊退化后不同景观类型土壤有机碳及其活性组分的分布特征及其影响因素。结果表明,5种景观类型土壤有机碳(SOC)、土壤可溶性有机碳(DOC)、土壤易氧化态有机碳(EOC)含量均较低。土壤SOC和EOC在垂直剖面上分布特征一致,土壤EOC与土壤有机质动态变化密切相关,土壤砂砾含量高是研究区土壤有机碳含量较低的主要原因。

Distribution Characteristics of Soil Organic Carbon and Its Active Components in Wetland and Influencing Factors

Hongjiannao Lake Wetland was an important ecological barrier of the northwest semi-arid desert region.With the decrease and intensive soil deterioration of the lake area,five kinds of typical landscape (salt marshes,swampy meadows,grasslands,steppe sand,sand) were formed gradually.On the basis of field investigation,Manggaitu and Erlintu sub-basins in Hongjiannao were selected to study the distribution characteristics of soil organic carbon and its active components in different landscapes after deterioration of the lake and its influencing factors.The results showed that soil organic carbon (SOC),soil dissolved organic carbon (DOC) and easily oxidized organic carbon (EOC) in the five kinds of typical landscape were extremely low.Distribution characteristics of soil SOC and EOC in the vertical profiles were consistent.Comprehensive analysis indicated that soil EOC was a sensitive indicator of soil organic matter dynamics.High soil gravel content was the main cause for low soil organic carbon content in the studied region.