乌鲁木齐达坂城山区地衣生态位特征的研究

为揭示达坂城山区地衣对生境资源的利用状况及竞争程度,该研究在野外设置30个样方并调查其物种盖度数据,利用生态位宽度、生态位重叠指数及排序分析,探讨达坂城山区地衣的生态位特征及环境影响因子。结果表明:(1)达坂城山区生态位最宽的为丽黄鳞衣(Rusavskia elegans)和内卷野粮衣(Circinaria contorta),对不同环境具有较强的适应性,其他地衣物种生态位宽度较窄,对环境资源利用程度低。(2)物种间生态位重叠值整体偏低,生态位重叠值较高的物种对极少,地衣物种生态位分化程度高,物种间竞争不激烈。(3)生态位较宽的物种与多数物种之间都存在生态位重叠,但重叠值较低; 一些生态位较窄的物种与其他物种之间的生态位重叠值较高; 生态位重叠和生态位宽度之间并无直接的线性关系。(4)地衣物种沿海拔梯度分布具有差异,海拔、光照强度、湿度、风速和人为干扰是本地区地衣群落物种生态位特征差异的主导环境因子。综上所述,达坂城山区地衣物种由于生境资源的竞争占据各自独特的生态位,形成了生态位的分化,群落较为稳定,沿海拔梯度的生境条件差异是物种差异分布的重要原因。该研究可为地衣群落构建研究提供理论依据,并对该地区地衣物种的多样性和生境保护具有重要意义。

Niche characteristics of lichen in Dabancheng mountainous area, Urumqi

In order to reveal the status of habitat resource utilization and the degree of competition among lichens in Dabancheng mountainous areas. In this work, 30 plots were sampled in the field and the species cover data of the plots were investigated, and the niche characteristics and environmental factors of lichen community species were analyzed by using niche width, niche overlap index and ordination analysis in this Dabancheng mountainous area. The results were as follows:(1)The niche width of Rusavskia elegans and Circinaria contorta were the widest in Dabancheng mountainous area, indicating that they were more adaptable to different environments. The niche widths of other lichen species were narrow, indicating that the species used the environmental resources to a less extent.(2)The niche overlap value between species was generally low, with only a few species pairs having a high niche overlap value. The degree of niche differentiation between lichen species was high, indicating that the competition between species was not intense.(3)Although niche overlap was common among species with wider niche widths, niche overlap values were lower. However, some species with narrower niche widths had higher niche overlap values with other species. As a result, there was no clear linear relationship between niche overlap and niche width.(4)The distribution of lichen species varied along the altitudinal gradient, and altitude, light intensity, humidity, wind speed, and human disturbance were the dominant environmental factors for the different niche characteristics of lichen community species in the study area. In conclusion, as a result of habitat resource competition in Dabancheng mountainous area, lichen species occupied their own distinct niches, resulting in niche differentiation and relatively stable communities. The distribution of species differed significantly due to differences in habitat conditions along the altitudinal gradient. The results of this paper provides a theoretical basis for the study of lichen community assembly, which are of great significance to the conservation of lichen species diversity and habitat in the region.