同域分布中华鬣羚与中华斑羚时空生态位特征

为了解同域分布有蹄类在环境复杂的山地森林生境中以何种方式维持种间关系以实现稳定共存,基于物种分布模型与日活动模式分析了四川省岷山、邛崃、大相岭、小相岭和凉山五大山系同域分布中华鬣羚(Capricornis milneedwardsii)与中华斑羚(Naemorhedus griseus)的时空生态位特征。结果显示:(1)在四川省五大山系,中华鬣羚的适宜栖息地面积为28006.07 km²,占研究区总面积的26.18%,其中高适宜栖息地面积为10015.90 km²,中华斑羚的适宜栖息地面积为21073.32 km²,占研究区总面积的19.71%,其中高适宜栖息地面积为8396.22 km²;(2)中华鬣羚与中华斑羚在生境因子选择上相似性高、栖息地重叠面积大,其空间生态位重叠度指数D=0.776,I=0.949,其适宜栖息地的主要重叠区域位于岷山和邛崃山系;(3)中华鬣羚与中华斑羚的日活动节律重叠指数为0.812;(4)中华鬣羚与中华斑羚属于同域分布的资源利用型竞争物种,中华鬣羚的存在会显著影响中华斑羚的日活动节律(P=0.016);二者同域分布时都会增加其昼间活动强度,并增加活动高峰期的强度及持续时间。本研究初步分析了中华鬣羚与中华斑羚的时空生态位特征,揭示了二者在空间、时间生态位上种群共存及种间竞争的耦合关系。研究有利于深入理解同域分布动物时空生态位特征、近缘物种的共存机制及种间竞争关系,为有蹄类等珍稀野生动物种群及栖息地的保护提供科学参考。

Spatio-temporal niche characteristics of sympatric Chinese serow and Chinese goral

In order to understand how the sympatric distribution of ungulates maintains interspecific relationships to achieve stable coexistence in a complex mountain forest habitat, this study analyzed the spatial and temporal ecological niche characteristics of sympatric distribution of the Chinese serow (Capricornis milneedwardsii) and the Chinese goral (Naemorhedus griseus) in the Minshan, Qionglai, Daxiangling, Xiaoxiangling and Liangshan mountain systems in Sichuan Province based on species distribution models and daily activity patterns. The results showed that:(1) in the five mountains of Sichuan Province, the suitable habitat area of the Chinese serow was 28006.07 km², accounting for 26.18% of the total area of the study area, among which the highly suitable habitat area was 10015.90 km². The suitable habitat area of the Chinese goral was 21073.32 km², accounting for 19.71% of the total area of the study area, among which the highly suitable habitat area was 8396.22 km². (2) Niche overlap indices, calculated by ENMTools, showed that the two species had high overlap (D=0.776, I=0.949). The Chinese serow and the Chinese goral had high selection similarity on environmental variables and large habitat overlap area. In terms of spatial distribution, the main overlapping areas of the Chinese serow and the Chinese goral suitable habitats are the Minshan Mountain and the Qionglai Mountain. And, the overlapping area of suitable habitats is 12967.50 km², accounting for 46.30% and 61.54% of their total suitable habitat area, the overlapping area of highly suitable habitats was 5955.28 km², accounting for 59.46% and 70.93% of their highly suitable habitats. (3) There was no significant difference in daily activity rhythm between the Chinese serow and the Chinese goral (P=0.534), and the overlap index was 0.812. (4) They were exploitation competition species, and the presence of the Chinese goral significantly affected the daily activity rhythm of the Chinese serow (P=0.016). They increased their diurnal activity intensity and enhanced the intensity and duration of their peak activity when they were sympatric distribution. In this study, the spatial and temporal niche characteristics of the Chinese serow and the Chinese goral were analyzed, and the coupling relationship of population coexistence and interspecific competition in spatial and temporal niche was revealed. This study, on the one hand, is helpful to deeply understand the spatial and temporal niche characteristics of sympatric distribution animals, the coexistence mechanism and interspecific competition of the related species. On the other hand, it provides a scientific reference for the conservation of rare wildlife populations and habitats, such as ungulates.