放牧对沙地樟子松林土壤养分及微生物群落的影响  

Effects of grazing on soil nutrients and microbial community of Pinus sylvestris var.mongolica forest in sandy land

作　　者：张彤 刘静 韩叙 童郁强 魏亚伟[1,2] ZHANG Tong;LIU Jing;HAN Xu;TONG Yuqiang;WEI Yawei(College of Forestry,Shenyang Agricultural University,Shenyang 110866,Liaoning,China;Research Station of Liaohe-River Plain Forest Ecosystem,Chinese Forest Ecosystem Research Network,Changtu 112500,Liaoning,China)

机构地区：[1]沈阳农业大学林学院,辽宁沈阳110866 [2]辽宁辽河平原森林生态系统国家定位观测研究站,辽宁昌图112500

出　　处：《干旱区研究》2023年第2期194-202,共9页Arid Zone Research

基　　金：中国科学院战略性先导科技专项(XDA23070103);国家林业和草原局林草科技创新平台运行补助项目“辽宁辽河平原森林生态系统国家定位观测研究站运行补助”(2020132029,2021132053)。

摘　　要：为探究放牧对土壤养分和微生物群落的影响,本研究分别选取了放牧和围封沙地樟子松林为研究对象,基于高通量测序技术,并测定土壤化学指标,分析放牧与围封土壤中养分、微生物群落组成以及多样性的差异。研究结果显示:(1)放牧后全磷含量显著降低(P<0.05),土壤有机碳和全氮含量也降低,但差异并不显著(P>0.05)。(2)从土壤微生物群落组成上来看,真菌分类学门水平中担子菌门比例放牧显著低于围封(P<0.05),但对细菌门水平并未产生显著影响(P>0.05)。(3)就土壤微生物多样性而言,放牧极显著降低了细菌的Chao1指数和Shannon指数(P<0.01),对真菌群落多样性无明显影响(P>0.05),可见,放牧对土壤细菌多样性指数的影响较真菌更大。综上所述,沙地樟子松林的放牧行为对土壤养分及土壤微生物均有不同程度的负面影响,所以该地区应适度减少放牧行为,缓解土地压力,以保障樟子松人工林的可持续利用。A grazing and enclosed Pinus sylvestris var.mongolica forests in sandy land was selected to explore the effects of grazing on soil nutrients and microbial communities.The microbial community composition and diversity between grazing and enclosed soil was determined using high-throughput sequencing technology.Soil chemical indexes were determined for estimating variation in the nutrients.The results showed that total phosphorus content decreased significantly after grazing(P<0.05).Soil organic carbon and total nitrogen content also decreased,while ammonium nitrogen,nitrate nitrogen,and available phosphorus increased,but the change was not significant(P>0.05).The grazing and enclosed plots showed 17.1%-24.6%similarity in the soil microbial community composition and the OTUs of fungi and bacteria were lower in grazing than enclosed plots.At each classification level,the number of fungi and bacteria in grazing plots was less than that in enclosed plots.Results showed grazing significantly reduced the number of bacteria at the genus level(P<0.05).The proportion of basidiomycetes in grazing was significantly lower than that in enclosure(P<0.05).No significant indigenous effect on bacterial phylum level(P>0.05)was observed.In terms of soil microbial diversity,grazing significantly reduced the Chao1 index and Shannon index of bacteria(P<0.01),and had no significant effect on fungal community diversity(P>0.05).The effect of grazing on soil bacterial diversity index was greater than that of fungi.In summary,grazing in the Pinus sylvestris var.mongolica forest in sandy land has different degrees of negative impacts on soil nutrients and soil microorganisms.Therefore,the grazing should be moderately reduced in this region to alleviate land pressure and ensure the sustainable utilization of the Pinus sylvestris var.mongolica plantation.

关 键 词：沙地樟子松 放牧 土壤养分 土壤微生物 

分 类 号：S714.8[农业科学—林学] S714.3