Extinction debt of a common shrub in a fragmented landscape

1. Environmental stochasticity and low demographic rates may cause delayed extinctions of habitat-specialist species that were initially retained within remnant patches after habitat loss and fragmentation. Detecting such extinction debts opens opportunities to counteract future biodiversity loss, yet knowing the underlying causes of population declines is a basic need for targeting specific guidelines for conservation and restoration (e.g. habitat quantity, quality, or connectivity).
2. Here, we examine the extinction debt in the common Mediterranean shrub Myrtus communis (myrtle) occurring in woodland patches of a highly fragmented region that has lost nearly half of the remnant woodland cover during the last fifty years (1956–2002).
3. We sampled myrtle occurrence in 304 woodland patches and modelled its probability of occurrence in relation to patch size, patch disturbance and woodland cover in the surrounding landscape. In order to test for extinction debt evidence, we tested whe...

1. 环境随机性（environmental stochasticity）与较低的种群统计率，可能会导致生境丧失与片段化后最初留存于剩余生境斑块中的生境专性物种（habitat-specialist species）出现延迟灭绝现象。对这类灭绝债务（extinction debt）的检测，可为减缓未来生物多样性丧失提供干预路径；而明确种群下降的根本成因，则是制定针对性保护与修复指南（例如关注生境数量、质量或景观连通性）的核心前提。
2. 本研究聚焦于地中海常见灌木香桃木（Myrtus communis，俗称桃金娘），其分布于某高度片段化区域的林地斑块中；该区域在1956年至2002年的近五十年间，已丧失近半数剩余林地覆盖面积。
3. 本研究对304个林地斑块中的香桃木分布状况开展了系统采样，并围绕斑块面积、斑块干扰程度及周边景观的林地覆盖度，构建了香桃木的发生概率模型。为验证灭绝债务的存在证据，我们开展了相关检验（原文至此截断，原句结尾为“we tested whe...”）。