新疆阜康绿洲荒漠过渡带主要植物种的生态位分析

采用Levins公式和王刚生态重叠计测方法，对新疆阜康绿洲荒漠过渡带中的7个植物种，分别从群落梯度和3个单一生态因子（土壤水分维，土壤盐分维，土壤酸碱度维）上对其生态位分化进行了定量分析。结果如下：（1）在群落梯度上，生态位大小依次为红砂（0.7010），梭梭（0.6434），角果藜（0.4774），雾冰藜（0.3745），盐爪爪（0.3541），叉毛蓬（0.3354）和碱蓬（0.2769）；（2）红砂在土壤水分、土壤盐分、土壤酸碱度维上的生态位分别为0.5274，0.6039和0.3620，梭梭在这3维上分别为03320,0.3083和0.5103，从生态位宽度看，红砂和梭梭处于优势种地位，其余为非优势种；（3）每个物种在群落梯度上的生态位宽度基本大于在上述3个资源轴上的平均生态位；（4）红砂与梭梭在土壤盐分维上的生态位重叠最大（0.4203）。表明了这两个优势种在利用土壤盐分方面有相似的特性。

Analysis on the Niche of the Main Plant Species of Oasis-deseart Ecotone in Fukang of Xinjiang

The niche differentiation of 7 main species in oasis-desert ecotone in Fukang of Xinjiang was analyzed quantitatively with respect to community gradients and single ecological factor gradients, i.e. soil moisture, soil salinity and soil acidity, by Levins formula and the method by Wang gang. The results were as follows: (1) according to community gradients, the order of niche breadth was Reaumuria soongorica(0.7010), Haloxylon ammodendron(0.6434), Ceratocarpus arenarius(0.4774), Bassia dasyphylla(0.3745), Kalidium foliatum (0.3541), Petrosimonia sibirica(0.3354) and Suaeda acuminata(0.2769);(2) the niche breadths of R. soongorica were 0.5274, 0.6039, 0.3620, 0.7325 respectively on dimensions of soil moisture, soil salinity, soil acidity, and soil organic, and that of H. ammodendron were 0.3320, 0.3083, 0.5103 and 0.5353 on the 3 dimensions. The two plants were dominant species, and the others were dependent species based on their niche breadth;(3) Niche breadths of desert plants on community gradients were larger than the average on the 3 dimensions;(4) Niche overlaps between R. soongorica and H. ammodendron were the biggest on soil salinity dimension, it showed the two species had similar characteristics in absorbing soil salt. Level of niche were affected by biological factors such as soil moisture, soil salt, soil acidity and non-biological factors such as interspecies competition, exploitation and mankind destroy. In the area of the ecotone, species competed each other lightly view from their niche overlaps.