荒漠草原3种典型群落类型的土壤微生物量碳氮研究

发布时间：2019-05-10 17:16

【摘要】：采用氯仿熏蒸-浸提法,以宁夏盐池荒漠草原3种典型群落(柠条、沙蒿、短花针茅)类型为研究对象,分析了不同生境(冠下、丛间)和不同土层间(0~5、5~10、10~15cm)土壤理化性质及微生物量——微生物量碳(MBC)和微生物量氮(MBN)的变化特征。结果表明:(1)3种群落土壤微生物量变化差异较大,柠条、沙蒿和短花针茅群落土壤MBC含量分别为77.00~393.18、17.27~221.71和81.05~173.37mg/kg,MBN含量分别为7.59~64.81、1.43~13.95和4.25~22.13mg/kg,MBC和MBN含量均表现为:冠下丛间,且随土层深度的增加而降低,有明显的"沃岛效应"。(2)群落类型对土壤微生物量碳氮含量的变化有显著影响,3种典型群落类型下土壤微生物量熵(qMB)、碳氮比(C/N)、微生物量碳氮比(MBC/MBN)分别在0.76~4.10、15.02~52.50、5.34~23.07范围内变化,其比值在不同生境和不同土层深度的分布特征有明显差异。(3)3种典型群落类型的土壤MBC与SOC、MBN、qMB具有显著相关关系,土壤C/N与MBC/MBN呈显著正相关关系,表明土壤MBC、MBN具有一定的生物学指示特性,可以作为评价土壤质量的生物学指标。
[Abstract]:Three typical communities (Caragana korshinskii, Artemisia annua, Thunb.) in Yanchi desert steppe of Ningxia were studied by chloroform fumigation and extraction, and different habitats (under crown) were analyzed. Soil physical and chemical properties and microbial biomass-microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) were studied in different soil layers (0: 5, 5: 10, 10: 15 cm). The results showed that: (1) the soil microbial biomass of the three communities varied greatly. The soil MBC contents of Caragana korshinskii, Artemisia annua and Stipa brevis communities were 77.00 393.18, 17.27 卤221.71 and 81.05 卤173.37 mg 路kg ~ (- 1), respectively. The contents of MBN were 7.59 鈮，

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