广西植物2016，Vol.36Issue(7)：837-847,11.DOI:10.11931/guihaia.gxzw201409049
暖温带森林土壤微生物量、群落结构和活性对植物地下碳源的响应
Responses of soil microbial biomass, community structure and soil enzyme to below-ground carbon change in the warm-temperate forest ecosystem
摘要
Abstract
This study focuses on the controlling mechanisms of soil microbial community structure and function to the change of below-ground carbon inputs through root-trenching experiments in a typical forest ecosystem of the subtropical and temperate transitional zone in China. By combining field investigations and manipulation experiments, phospholipid fatty acids (PLFAs) and activities of soil extracellular enzymes were studied as indicators of soil microbial community <br> structure and functioning. We also studied the response characteristics of soil microbial biomass, community structure and activities in below-ground carbon inputs. The results showed that soil microbial biomass carbon in root-trenching plots reduced significantly in an age sequence of Quercus aliena forest (40-year-old, 80-year-old, and >160-year-old). Integrated over the entire experimental period; the mean difference of soil microbial biomass carbon in root-trenching plots were reduced between-8.72%and-5.72%, and the highest reduction was in the 80-year-old forests, whereas the lowest decline was in the 160-year-old forests. The variation of soil microbial biomass nitrogen was similar with the chan-ges of soil microbial biomass carbon in the forest stands of similar age, but compared with the control plots, it did not decrease significantly. In addition, compared with the control plots, the soil microbial biomass carbon and nitrogen in all forest stands increased after trench for 2 to 4 m. The root-trenching can produce different effects on soil microbial commu-nity structure in all forest stands, the response of microbial communities to the change of below-ground carbon input in 40-year-old forests were higher than the other two age groups. The relative abundances of saprotrophic fungal community in root-trenching plots was declined sharply in all stands, and it reduced significantly in 80 and 160-year-old forests com-pared to control. Other communities like bacteria, actinomycete and arbuscular mycorrhizal fungi changed slightly in all forest stands;the hydrolase activities ( i. e. β-1,4-glucosidase and β-1,4-N-acetylglucosaminidase) in root-trenching plots decreased remarkably in the 40, 80 and 160-year-old stands, but the oxidase activity (i.e. phenol oxidase and per-oxidase) was not diminish in all plots except 160-year-old stands. The root-trenching treatment had no obvious influence on soil moisture and soil temperature. By addressing the response characteristics of soil microbial biomass, community structure and function on the plant root carbon input, this study sheds light on the trends of soil microbial structure and function change under the context of global climate change. This study shows the need for more accurate prediction trends of forest soil carbon in the future.关键词
微生物量碳/微生物量氮/微生物群落结构/土壤酶活性/壕沟处理/年龄序列/暖温带森林Key words
microbial biomass carbon/microbial biomass nitrogen/microbial community structure/soil enzyme activi-ty/trenching/chronosequence/warm-temperate forest分类
农业科技引用本文复制引用
尤业明,王娟,黄雪蔓,孙筱璐,唐佐芯..暖温带森林土壤微生物量、群落结构和活性对植物地下碳源的响应[J].广西植物,2016,36(7):837-847,11.基金项目
国家科技支撑计划项目(2011BAC09B02)[Supported by National Key Technology R ＆D Program of China(2011BAC09B02)]。 （2011BAC09B02）
