基于盐分梯度的荒漠植物多样性与群落、种间联接响应  

Responses of desert plant diversity,community and interspecific association to soil salinity gradient

作　　者：张雪妮[1,2] 吕光辉[1,2] 杨晓东[3,4] 贡璐[1,2] 秦璐[1,2] 何学敏[1,2] 刘昊奇[1,2] 

机构地区：[1]新疆大学资源与环境科学学院,乌鲁木齐830046 [2]绿洲生态教育部重点实验室,乌鲁木齐830046 [3]华东师范大学环境科学系,上海200062 [4]浙江天童森林生态系统国家野外科学观测研究站,宁波315114

出　　处：《生态学报》2013年第18期5714-5722,共9页Acta Ecologica Sinica

基　　金：国家自然科学重点基金项目(41130531)

摘　　要：土壤盐分是影响干旱区荒漠植物群落动态的决定因素之一。基于样方调查和不同土壤盐分梯度下植物多样性指数及群落与种间关联的计算结果,分析干旱区荒漠群落植物多样性、群落联接性和种间关联对土壤盐分梯度的响应动态。结果表明,在土壤盐含量为0.03%—0.55%(S1)、0.61%—1.24%(S2)和1.41%—1.79%(S3)的盐分梯度上,(1)随土壤盐含量升高,群落生活型结构改变,草本比例减少,乔木比例增加;(2)植物多样性指数随土壤盐分增加而下降,低盐分梯度下,二者极显著正相关(P<0.01),中盐梯度下二者间呈部分显著负相关(P<0.05),高盐梯度下则转为以正相关为主(P>0.05);(3)群落联接性随土壤盐分梯度转变,在0.61%—1.24%的中度盐含量时正联接性最强(VR=1.89),高盐度含量下群落转为不显著的负联接,稳定性降低;(4)沿盐分升高梯度,种间的负相关种对数增加,正相关种对数减少,种间关联(相关)强度提高,正负相关种对比(PNR)与多样性指数呈显著正相关(P<0.05)。综上可知,干旱区荒漠植物多样性在土壤盐含量达到1.41%—1.79%水平时总体显著降低;土壤盐分水平显著影响植物群落和种间联接性,种间互利性随盐分梯度增加下降,物种趋于独立分布,并最终导致荒漠植物多样性降低。Dynamic response of plant diversity, community and interspecific association along environmental gradients is one of the basic issues in community ecology and biodiversity science. Soil salinity is one of the most decisive factors that govern desert plant community dynamics. The Ebinur Lake wetland national nature reserve is located in typical arid desert area. Previous related studies about the reserve had point out that soil salinity influences the desert plant community characteristic significantly, but the specific role of soil salinity in plant community dynamics is still unknown. Based on this, the objective of this study is focused on the responses of desert plant diversity, community overall association and interspecific association to soil salinity gradient. In this study, altogether 74 sampling plots were investigated; including 22 plots for trees （ 10 m×10 m） , 35 plots for shrubs （5 m×5 m） and 17 plots for herbs （ 1 m×1m）. At each plot, abundance, height and diameter at breast height oftrees, abundance of shrubs and herbs were surveyed. classified to 3 salinity gradients by cluster analysis, defined as 0.03%-0.55% （ S1 ） , 0.61%-1.24% According to soil salinity of the corresponding plot, all plots were with the salt contents of low （S1）, middle （$2） and high （S3） （$2） and 1.41%--1.79% （$3） respectively. A range of different diversity indices including Shannon-Wiener, Simpson, Pielou, Fisher-a of logarithmic series distribution and Margalef were calculated to examine the plant diversity under each salinity gradient. Variance ratio （ VR）, X2 test and Spearman rank correlation were employed to quantitatively analyze the community overall association and interspecific association under different salinity gradient. VR value, proportion of species pairs with positive and negative correlation, Dice index and Spearman rank correlation coefficient were used in exploring response of overall association and interspecific association to different soil salinity. The resu

关 键 词：盐分梯度 土壤盐分 荒漠植物 植物多样性 群落联接 种间关联 

分 类 号：Q948[生物学—植物学]