School of Biological Sciences, University of Bristol, Bristol, BS8 1TQ, UK.
Department of Watershed Sciences and the Ecology Center, Utah State University, Old Main Hill, Logan, UT, USA.
Oecologia. 2022 May;199(1):193-204. doi: 10.1007/s00442-022-05178-9. Epub 2022 May 6.
Biodiversity is declining at an unprecedented rate, highlighting the urgent requirement for well-designed protected areas. Design tactics previously proposed to promote biodiversity include enhancing the number, connectivity, and heterogeneity of reserve patches. However, how the importance of these features changes depending on what the conservation objective is remains poorly understood. Here we use experimental landscapes containing ciliate protozoa to investigate how the number and heterogeneity in size of habitat patches, rates of dispersal between neighbouring patches, and mortality risk of dispersal across the non-habitat 'matrix' interact to affect a number of diversity measures. We show that increasing the number of patches significantly increases γ diversity and reduces the overall number of extinctions, whilst landscapes with heterogeneous patch sizes have significantly higher γ diversity than those with homogeneous patch sizes. Furthermore, the responses of predators depended on their feeding specialism, with generalist predator presence being highest in a single large patch, whilst specialist predator presence was highest in several-small patches with matrix dispersal. Our evidence emphasises the importance of considering multiple diversity measures to disentangle community responses to patch configuration.
生物多样性正以前所未有的速度减少，这突出表明需要精心设计的保护区。以前提出的促进生物多样性的设计策略包括增加保护区斑块的数量、连通性和异质性。然而，这些特征的重要性如何根据保护目标的不同而变化，目前还了解甚少。在这里，我们使用含有纤毛虫原生动物的实验景观来研究栖息地斑块的数量和大小异质性、相邻斑块之间的扩散率以及穿越非栖息地“基质”的扩散死亡率如何相互作用，从而影响多种多样性措施。我们表明，增加斑块的数量会显著增加γ多样性并减少整体灭绝数量，而具有异质斑块大小的景观比具有同质斑块大小的景观具有更高的γ多样性。此外，捕食者的反应取决于它们的摄食特化，在单个大斑块中存在的广谱捕食者数量最高，而在具有基质扩散的几个小斑块中存在的专业捕食者数量最高。我们的证据强调了考虑多种多样性措施以解开对斑块配置的群落反应的重要性。
