采煤塌陷区不同裂缝宽度下草本植物群落特征及其生态位

Characteristics of Herbaceous Plant Communities and Their Ecological Niche Under Different Crack Widths in Coal Mining Subsidence Area

为揭示草甸草原区采煤塌陷地裂缝不同裂缝宽度下对草本植物群落组成、群落稳定性及生态位特征,以西乌珠穆沁旗白音华四号矿采煤塌陷区为研究区,通过野外调查与室内分析相结合的方法对研究区内不同裂缝宽度(W)下的(W≤5 cm)(5 cm<W≤10 cm)(10 cm<W≤15 cm)草本植物群落进行了对比分析。结果表明:①随着土地裂缝宽度的增大,植物群落盖度减少;生物量减小;物种丰富度指数、Simpson优势度指数、Shannon-Wiener指数、Pielou均匀度指数减小;②优势草本菊科的植物的生态位宽度呈现出递减的趋势,禾本科植物呈现上升趋势。并且种群内种间生态位重叠度的增大,加剧了物种间对同种资源的利用率增大;③草地群落的M.Godron稳定性测定结果距离稳定点坐标(20,80)越远,欧氏距离越大群落稳定性越差。因此研究区内土地裂缝宽度的增大降低了草地植被覆盖与生产力,减少了植物群落物种丰富度与多样性,同时增大了植物群落物种对资源利用能力与种间竞争。

In order to reveal the community composition,community stability and niche characteristics of herbaceous plants under different crack widths of ground fissures in coal mining subsidence in meadow steppe area,this study took the coal mining subsidence area of Baiyinhua No.4 Mine in West Ujimqin Banner as the research area.Through the combination of field investigation and indoor analysis,the herbaceous plant communities under different crack widths(W≤5cm)(5cm<W≤10cm)(10cm<W≤15cm)in the study area were compared and analyzed.The results showed that:①With the increase of the width of the land fissure,the coverage of the plant community decreased;biomass decreased;the species richness index,Simpson diversity index,Shannon Wiener diversity index and evenness index decreased.②The niche breadth of dominant herbaceous Compositae plants showed a decreasing trend,and Gramineae plants showed an upward trend.In addition,the increase of niche overlap between species in the population aggravates the increase of the utilization rate of the same resource between species.③The farther away from the stable point coordinates(20,80),the greater the Euclidean distance,the worse the stability of the community.Therefore,the increase of land fissure width in the study area reduced the vegetation coverage and productivity of grassland,reduced the species richness and diversity of plant communities,and increased the resource utilization ability and interspecific competition of plant community species.