放牧对赖草群落生物量及植物多样性的影响  

Effects of Grazing on the Biodiversity and Productivity of Leymus secalinus Communities

作　　者：刘晓妮 李刚[2] 赵祥[2] 张宾宾[2] 刘碧荣[2] 董宽虎[2] 王永新[2] 任国华[2] 

机构地区：[1]山西省生态畜牧产业管理站,山西太原030001 [2]山西农业大学动物科技学院,山西太谷030801

出　　处：《草地学报》2014年第5期942-948,共7页Acta Agrestia Sinica

基　　金：中国科学院战略性先导科技专项(XDA05050403);公益性行业(农业)科技专项(201403050);山西农业大学学术骨干项目资助

摘　　要：通过对围封5年与自由放牧的赖草(Leymus secalinus)群落进行整个生长季的生物量和物种多样性动态观测,旨在了解放牧对赖草群落的影响。结果表明:整个生长季围栏内外赖草始终占据主导地位,放牧样地物种丰富度指数显著高于围封样地(P<0.05),多样性指数和均匀度指数在不同时期变化趋势不同;赖草群落地上生物量、高度、盖度、物种丰富度、多样性指数和均匀度指数在整个生长季均表现为先增加后降低,放牧显著降低群落地上生物量(P<0.05),在整个生长季放牧使群落盖度平均降低31.82%,群落高度平均降低36.37 cm围封样地群落地下生物量在7月和9月出现2个峰值,分别为4148.4和4359.27 g·m^(-2),放牧样地地下生物量在8月达到最大,为2559.28 g·m^(-2);群落地下生物量随土层深度的增加所占比例逐渐减小,其中围封和放牧样地0~30 cm土层所占比例分别为75.64%和77.37%。适度放牧有利于促进赖草群落的物种多样性,不合理放牧降低草地植物群落的盖度、高度和生物量,因此围栏封育能够促进赖草草地的稳定和可持续发展。In order to understand the effects of grazing on Leymus secalinus communities,the biomass and species diversity dynamics of L.secalinus communities were investigated throughout the growing season under five years fenced and free-grazing sites,respectively.Results showed that plant communities were dominated by L.secalinus throughout the growing season in both fenced and free-grazing plots.Species richness index in the grazing plots was significant higher than that in the fenced plots.In addition,diversity index and evenness index did not show the same trend at different periods.Aboveground biomass,height,coverage,species richness,diversity index and evenness index of L.secalinus communities increased firstly and then decreased in the entire growing season.Grazing significantly reduced the aboveground biomass of L.secalinus communities.Throughout the growing season,the coverage of community decreased by 31.82% and the plant height reduced to 36.37 cm after grazing.Belowground biomass in fenced plots appeared two peaks,including July （4148.4 g · m 2） and September （4359.27 g · m-2）,while the maximum belowground biomass in free-grazing plots happened in August for 2559.28 g · m-2.With increasing soil depth,belowground biomass proportion of L.secalinus communities gradually reduced,which of fenced and free-grazing plots were 75.64% and 77.37%,respectively.All results indicated that moderate grazing had significant positive impact on the species diversity of L.secalinus communities,while unreasonable grazing decreased the coverage,height and biomass of plant communities,so fenced grazing significantly promoted stability and sustainable development in L.secalinus grassland.

关 键 词：围封 放牧 赖草群落 生物量动态 群落特征 

分 类 号：Q948.15[生物学—植物学]