半干旱地区湿地-干草原生态系统植物群落多样性分析

Diversity of plant community in the ecosystem of wetlands-steppe in semi-arid area based on polar ordination

利用极点排序法对宁夏盐池县四儿滩湿地交错带的边界进行确定,并在此基础上研究其植物的生物多样性.结果表明：1）沿湿生带-交错带-旱生带的生境梯度,交错带划分结果为北样线交错带样方为N8 ～ N13,南样线为S15～ S24,东样线为E13 ～ E22,西样线为W23～W30.2）4条样线多样性指数与丰富度指数均表现为交错带＞旱生带＞湿生带,均匀度指数均表现为旱生带＞交错带＞湿生带,优势集中性指数均表现为湿生带＞交错带＞旱生带.3）受人为干扰和地形差异的影响,不同方向植物群落差异较大,北样线和东样线丰富度指数、多样性指数、均匀性指数较高,优势集中性指数较低.

We determined the boundary of Siertan Wetland at Yanchi County in Ningxia using the polar ordination method,and investigated the biodiversity of the study area.Along the biotope gradient from wetland to grassland,the ectone could be divided into the quadrats N8-N13 in the north transect line,quadrats S15-S24 in the south transect line,quadrats El3-E22 in the east transect line,and quadrats W23-W30 in the west transect line ; The diversity index and richness index of the four transect lines all followed the order of ectone ＞ arid region ＞ wet region,the evenness index ordered as arid region ＞ectone ＞ wet region,and the dominant concentration index ranked as wet region ＞ ectone ＞ arid region.Affected by human disturbance and topographical difference,the plant communities varied in different directions,and the richness index,diversity index and evenness index of the north and east transect lines were higher,while the dominant concentration index was lower.