黄河源区斑块化退化高寒草甸土壤微生物多样性对长期封育的响应  

Response of Soil Microbial Diversity to Long-term Enclosure in Degraded Patches of Alpine Meadow in the Source Zone of the Yellow River

作　　者：杨鹏年 李希来[1,2] 李成一[1] 段成伟 YANG Peng-nian;LI Xi-lai;LI Cheng-yi;DUAN Cheng-wei(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China;State Key Laboratory of Plateau Ecology and Agriculture,Qinghai University,Xining 810016,China)

机构地区：[1]青海大学农牧学院,西宁810016 [2]青海大学高原生态与农业国家重点实验室,西宁810016

出　　处：《环境科学》2023年第4期2293-2303,共11页Environmental Science

基　　金：国家自然科学联合基金项目(U21A20191);青海省自然科学基金创新团队项目(2020-ZJ-904);高等学校学科创新引智计划项目(D18013);青海省科技创新创业团队项目。

摘　　要：为了明确黄河源区斑块化退化高寒草甸土壤细菌和真菌群落对长期封育的响应特征,通过对土壤理化性质分析和高通量测序技术,对1年期(E1)、短期(E4)和长期(E10)围栏封育下土壤pH、含水量、养分和微生物群落组成及多样性进行分析.结果表明,E1封育显著降低土壤pH,而长短期封育均显著提高土壤pH,长期封育能显著提高土壤含水量和全氮含量,短期封育能显著提高土壤速效磷含量.长期封育能显著提高细菌变形菌门(Proteobacteria)和真菌子囊菌门(Ascomycota)相对丰度,短期封育能显著提高细菌酸杆菌门(Acidobacteriota)相对丰度,但长短期封育均使真菌担子菌门(Basidiomycota)相对丰度下降;随着封育年限的延长,细菌的Chao1和Shannon多样性指数呈增加趋势,长短期封育无显著差异,真菌的Chao1指数逐渐增加,Shannon多样性指数先增加后减小,长短期封育无显著差异.冗余分析(RDA)表明,围栏封育主要通过改变土壤pH和含水量来改变微生物群落组成和结构.因此,E4短期封育能明显改善斑块化退化高寒草甸的土壤理化性质和微生物多样性,无需进行长期封育,否则会造成草地资源浪费、生物多样性减少、限制野生动物活动等诸多不利影响.The soil pH,water content,nutrients,and microbial community composition and diversity among one-year term(E1),short-term(E4),and long-term(E10)enclosures were analyzed for understanding the response of soil bacterial and fungal communities to long-term enclosure in degraded patches of alpine meadow in the source zone of the Yellow River,through determining the soil physicochemical properties and microbial diversity using high-throughput sequencing technology.The results showed that the E1 enclosure significantly decreased soil pH,whereas long-term and short-term enclosures increased soil pH.The long-term enclosure could significantly increase soil water content and total nitrogen content,and the short-term enclosure could significantly increase available phosphorus content.The long-term enclosure could significantly increase the bacterial Proteobacteria.The short-term enclosure could significantly increase the abundance of the bacteria Acidobacteriota.However,the abundance of the fungus Basidiomycota decreased in both long-term and short-term enclosures.With the extension of enclosure years,the Chao1 index and Shannon diversity index of bacteria showed an increasing trend,but there was no significant difference between long-term and short-term enclosures.The Chao1 index of fungi gradually increased,and the Shannon diversity index first increased and then decreased,but there was no significant difference between long-term and short-term enclosures.Redundancy analysis indicated that enclosure altered microbial community composition and structure mainly by changing soil pH and water content.Therefore,the E4 short-term enclosure could significantly improve the soil physicochemical properties and microbial diversity at the degraded patches of alpine meadow.The long-term enclosure is not necessary and will lead to the waste of grassland resources,reduction in biodiversity,and restriction of wildlife activities.

关 键 词：斑块化退化 高寒草甸 围栏封育 土壤理化性质 微生物多样性 

分 类 号：X172[环境科学与工程—环境科学]