黄土丘陵区小流域侵蚀环境对土壤微生物量及酶活性的影响  

Effect of erosion on soil microbial biomass and enzyme activity in the Loess Hills

作　　者：杨佳佳[1,2] 安韶山[1,2] 张宏[2] 陈亚南[2] 党廷辉[1,2] 焦菊英[1] 

机构地区：[1]西北农林科技大学,黄土高原土壤侵蚀与旱地农业国家重点实验室,杨陵712100 [2]西北农林科技大学资源环境学院,杨陵712100

出　　处：《生态学报》2015年第17期5666-5674,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金重点基金(41030532);国家自然科学基金面上项目(41171226);教育部新世纪优秀人才支持计划(NCET-12-0479)

摘　　要：土壤侵蚀环境直接影响土壤的特性,对土壤微生物的形成和稳定具有重要的影响。土壤微生物量推动着土壤的物质循环和能量流动,对土壤中各种环境的变化有很强的敏感性。土壤酶活性能表示土壤微生物功能的多样性,与土壤微生物量有着紧密的联系。为了探究不同侵蚀环境对土壤微生物量和酶活性的影响,以黄土丘陵区陈家坬小流域为研究区,选择5种不同侵蚀环境下0—10cm和10—20cm土层的土壤为研究对象,对土壤微生物量及其土壤蔗糖酶、脲酶和碱性磷酸酶活性进行了研究。结果表明:(1)土壤微生物量碳、氮、磷含量均表现为0—10cm大于10—20cm土层;土壤微生物量碳和磷在阴沟坡最大,在阳梁峁坡和峁顶较小,且阴沟坡和峁顶差异显著;土壤微生物量氮在阳沟坡最大,阴阳梁峁坡最小,差异性显著(P<0.01)。(2)土壤脲酶、蔗糖酶和碱性磷酸酶活性均表现为0—10cm大于10—20cm土层,且在不同侵蚀环境下均表现为阴梁峁坡最大,阳梁峁坡最小。(3)相关性分析表明,土壤微生物量碳、氮、磷与土壤脲酶、蔗糖酶、碱性磷酸酶活性之间均有极显著的正相关。Erosion directly affects soil characteristics and has a significant effect on the formation and stability of the soil microbial community. Soil microbial biomass not only plays a significant role in energy flow and nutrient cycling, but it also shows great sens!tivity to changes in soil environment. Soil enzyme activities are indicative of the functional diversity of the soil microbial community, as they are closely associated with soil microbial biomass. To reveal the effect of different erosion environments on soil microbial biomass and soil enzyme activities, soil samples were collected from the Chengjiawa watershed, located in the Yanhe watershed of the hill and gully region of Ansai County, Yan＇an, Shaanxi Province, China. Soil samples were collected from five erosion environments in the valley, at depths of 0--10 cm and 10--20 cm. We studied the characteristics of soil microbial biomass including carbon, nitrogen, and phosphorus, soil enzyme activities including soil urease, invertase, and alkaline phosphatase, and correlations between soil microbial biomass and enzyme activities. The results showed that： （1） Soil microbial biomass carbon, nitrogen, and 0--10 cm and 10--20 cm soil layers; soil microbial biomass carbon and phosphorus were significantly different between the phosphorus in the shaded lower slopes were higher than in the other tested environments, whereas in the sunny middle slope and the hill top they were lower than in the other tested soil environments. The difference between the shaded lower slopes and sunny hill top were significant. Soil microbial biomass nitrogen in the sunny lower slope was significantly higher than in the other tested soil environments. Overall, soil microbial biomass of the ditch slope was higher than in the other tested environments. This suggested that the erosion affects the soil microbial properties, and that soil nutrient accumulation and mineralization ability of soils on the downhill slope were higher than in other tested locations. （2） Soil urease,

关 键 词：黄土丘陵 侵蚀环境 土壤微生物量 酶活性 

分 类 号：S157[农业科学—土壤学]