Factors preventing the recovery of New Zealand forests following control of invasive deer
Factors preventing the recovery of New Zealand forests following control of invasive deer
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DOI：
10.1046/j.1523-1739.2003.15099.x
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发表时间：
2003-04-01
影响因子：
6.3
通讯作者：
Lee, WG
中科院分区：
文献类型：
--
作者：
Coomes, DA;Allen, RB;Lee, WG
目前，人们对恢复受入侵生物影响的生态系统非常感兴趣。在新西兰，鹿在19世纪被引入，导致一些森林的下层植被组成和结构发生了巨大变化。鹿喜欢在矮乔木上觅食，这些矮乔木大多与早期演替林分和湿润肥沃地有关，但许多高乔木只有在其他食物来源稀缺时才会觅食。政府在控制项目上投入了大量资金，旨在减少鹿的数量，从而使森林恢复到接近入侵前的组成和结构，但收效甚微。在文献综述的基础上，我们给出了鹿的影响可能不可逆的几个情况的例子，包括：(1)由于饮食转换，即使在鹿密度低的情况下，美味物种仍然是高浏览的；(2)鹿群不吃的植物占据空出的生态位；(3)种子来源的局部灭绝；(4)演替途径的根本性改变；(5)生态系统过程的变化；（六）其他外来动物归化，削弱单种控制效果的；(7)外来植物削弱了单种防治的效果。我们考虑了科学研究对有效森林恢复的贡献，包括基于经验的森林动力学模型，该模型将更新置于其他过程（如干扰、土壤肥力和多种入侵生物）的背景下。
There is currently great interest in restoring ecosystems affected by invasive organisms. In New Zealand, deer were introduced during the nineteenth century, causing dramatic changes to the understory composition and structure of some forests. Deer prefer to browse on short tree species, mostly associated with early successional stands and moist-fertile sites, but many tall tree species are browsed only when other food sources are scarce. The government has invested heavily in control programs aimed at reducing deer numbers and thereby restoring forests to something approaching their preinvasion composition and structure, but have met with only limited success. Based on a literature review, we give several examples of situations in which deer impacts may not be reversible, including the following: (1) palatable species remaining highly browsed even at low deer densities as a result of diet switching; (2) occupation of vacated niches by plant species not eaten by deer; (3) local extinction of seed sources; (4) fundamental alterations to successional pathways; (5) shifts in ecosystem processes; (6) other exotic animals becoming naturalized and weakening the effectiveness of single-species control; and (7) exotic plants weakening the effectiveness of single-species control. We consider the contributions that scientific research can make to effective forest restoration, including empirically based forest-dynamics models that place regeneration in the context of other processes, such as disturbance, soil fertility, and multiple invasive organisms.