CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Universidade do Porto, Campus de Vairão, 4485-661, Vairão, Portugal.
BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661, Vairão, Portugal.
Sci Rep. 2023 Nov 30;13(1):21113. doi: 10.1038/s41598-023-48204-3.
Species' ecological niches are frequently analysed to gain insights into how anthropogenic changes affect biodiversity. Coping with these changes often involves shifts in niche expression, which can disrupt local biotic interactions. Secondary contact zones, where competition and ecological segregation commonly occur, are ideal for studying the ecological factors influencing species' niches. In this study, we investigated the effect of climate and landscape factors on the ecological niches of two viper species, Vipera aspis and Vipera latastei, across three contact zones in northern Iberia, characterized by varying levels of landscape alteration. Using niche overlap tests, ecological niche models and spatial analyses we observed local variation in the expression of the species' niches across the three contact zones, resulting from the different abiotic and biotic conditions of each area. Rather than spatial niche segregation, we observed high niche overlap, suggesting niche convergence. A pattern of asymmetrical niche variation was identified in all contact zones, driven by species' climatic tolerances and the environmental conditions of each area. V. aspis generally exhibited a wider niche, except in the southernmost zone where the pure Mediterranean climate favored V. latastei. Human-induced landscape changes intensified niche asymmetry, by favoring the most generalist V. aspis over the specialist V. latastei, increasing habitat overlap, and likely competition. This study presents a comprehensive analysis of niche expression at range margins, anticipating a heightened impact of landscape changes in V. latastei. The methodological framework implemented here, and our findings, hold significant relevance for biodiversity management and conservation in human-impacted areas.
物种的生态位经常被分析，以深入了解人为变化如何影响生物多样性。应对这些变化通常涉及生态位表达的转变，这可能会破坏当地的生物相互作用。二次接触区是研究影响物种生态位的生态因素的理想场所，在这些区域，竞争和生态隔离通常会发生。在这项研究中，我们调查了气候和景观因素对分布于伊比利亚北部三个接触区的两种蝰蛇（Vipera aspis 和 Vipera latastei）的生态位的影响，这些接触区的景观改造程度不同。通过生态位重叠测试、生态位模型和空间分析，我们观察到由于每个地区的不同生物和非生物条件，物种生态位在三个接触区的表达存在局部变化。我们观察到高生态位重叠，而不是空间生态位隔离，这表明生态位趋同。在所有接触区中都存在不对称的生态位变化模式，这是由物种的气候耐受性和每个地区的环境条件驱动的。V. aspis 通常表现出更广泛的生态位，除了在最南端的区域，那里纯粹的地中海气候有利于 V. latastei。人类引起的景观变化通过有利于更普遍的 V. aspis 而不是更专业的 V. latastei，增加了栖息地重叠，并可能增加了竞争，从而加剧了生态位不对称性。这项研究全面分析了分布范围边缘的生态位表达，预计景观变化对 V. latastei 的影响将更加显著。这里实施的方法框架和我们的研究结果对于人类影响地区的生物多样性管理和保护具有重要意义。
