Department of Conservation Biology, Helmholtz Center for Environmental Research-UFZ, Leipzig, Germany.
Department of Landscape Ecology, Helmholtz Center for Environmental Research-UFZ, Leipzig, Germany.
PLoS One. 2020 Mar 5;15(3):e0229600. doi: 10.1371/journal.pone.0229600. eCollection 2020.
The effects of habitat loss on the distribution of populations are often linked with species specialization degree. Specialist species can be more affected by changes in landscape structure and local patch characteristics compared to generalist species. Moreover, the spatial scale at which different land covers (eg. habitat, cropland, urban areas) affect specialist species can be smaller. Specialization is usually assumed as a constant trait along the distribution range of species. However, for several taxa, there is evidence of higher specialization degree in peripheral populations compared with populations in the core. Hence, peripheral populations should have a higher sensitivity to habitat loss, and strongest effects should be found at a smaller spatial scale. To test these expectations, we implemented a patch-landscape approach at different spatial scales, and compared effects of landscape structure and patch characteristics on occupancy probability among northern peripheral, more specialized populations (Czech Republic) and core populations (Bulgaria) of the eastern green lizard Lacerta viridis. We found that landscape structure and patch characteristics affect differently the occupancy probability of Lacerta viridis in each region. Strongest effects of habitat loss were found at a spatial scale of 150m around patches in the periphery, but at a scale of 500m in the core. In the periphery occupancy probability of populations was principally affected by landscape composition, and the effect of habitat quality was stronger compared to core populations. In the core, persistence of populations was mainly explained by characteristics of the spatial configuration of habitat patches. We discuss possible ecological mechanisms behind the relationship between sensitivity to habitat loss, populations' specialization degree and position in the distribution range, and suggest conservation measures for L. viridis.
栖息地丧失对种群分布的影响通常与物种专业化程度有关。与广域种相比， specialistspecies 更容易受到景观结构和局部斑块特征变化的影响。此外，不同土地覆盖物（如栖息地、耕地、城市区域）影响 specialistspecies 的空间尺度可能更小。专业化通常被认为是物种分布范围的一个恒定特征。然而，对于许多分类群，有证据表明外围种群的专业化程度高于核心种群。因此，外围种群对栖息地丧失应该更敏感，并且在较小的空间尺度上应该会发现最强的影响。为了检验这些预期，我们在不同的空间尺度上实施了斑块-景观方法，并比较了景观结构和斑块特征对东部绿蜥蜴 Lacerta viridis 北方外围、专业化程度较高的种群（捷克共和国）和核心种群（保加利亚）的占有概率的影响。我们发现，景观结构和斑块特征对每个地区的 Lacerta viridis 占有概率有不同的影响。在边缘地区斑块周围 150m 的空间尺度上，栖息地丧失的最强影响，而在核心地区则为 500m。在边缘地区，种群的占有概率主要受景观组成的影响，与核心种群相比，生境质量的影响更强。在核心地区，种群的持续存在主要由栖息地斑块空间配置的特征来解释。我们讨论了栖息地丧失敏感性、种群专业化程度与分布范围位置之间关系背后的可能生态机制，并为 L. viridis 提出了保护措施。
