Response of lizard community structure to desert grassland restoration mediated by a keystone rodent
Response of lizard community structure to desert grassland restoration mediated by a keystone rodent
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蜥蜴群落结构对关键啮齿动物介导的荒漠草原恢复的响应
DOI：
10.1007/s10531-013-0459-7
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发表时间：
2013
影响因子：
3.4
通讯作者：
John M. Coffman
中科院分区：
文献类型：
--
作者：
Bradley J. Cosentino;R. Schooley;B. Bestelmeyer;John M. Coffman
奇瓦瓦沙漠的许多草原已经转变为以灌木丛(Larrea Tridentata)为主的灌木丛。草原恢复工作的目标是通过在大空间范围内使用除草剂来控制杂草丛。然而，我们对景观规模的恢复如何影响生物多样性的了解有限。我们研究了美国新墨西哥州南部的恢复处理是否影响了对灌木入侵敏感的蜥蜴的群落结构。我们比较了7至29年前使用除草剂处理的21个地区与以灌木为主、地貌、土壤和海拔相匹配的配对未处理地区的蜥蜴群落结构。为了研究对恢复的潜在反应机制，我们测试了草原专家单胞螺旋藻的丰度是否取决于自处理以来的时间、处理区域和隔离以及当地栖息地质量。由于蜥蜴以啮齿动物洞穴为栖息地，我们测试了群落结构和单亲蜥蜴的丰度是否取决于关键啮齿动物Dipodomys spectabilis的丰度。与未处理的地区相比，经过处理的地区灌木覆盖率降低，草地覆盖率增加。不同地区的蜥蜴群落组成差异很大，有4种蜥蜴对处理有反应。处理对和未处理对之间的群落组成差异在老处理下最大(≥22年)，群落组成受斑潜蝇的影响。特别是，在具有较高密度的斑纹夜蛾的旧处理中，唯一隐翅虫的丰度最大。总体而言，我们的结果表明蜥蜴群落结构对草原恢复的努力做出了响应，关键物种可以影响恢复结果。关键物种的重建可能是栖息地恢复后恢复动物生物多样性的关键制约因素。
Many grasslands in the Chihuahuan Desert have transformed to shrublands dominated by creosotebush (Larrea tridentata). Grassland restoration efforts have been directed at controlling creosotebush by applying herbicide over large spatial scales. However, we have a limited understanding of how landscape-scale restoration affects biodiversity. We examined whether restoration treatments in southern New Mexico, USA have influenced the community structure of lizards, which are sensitive to shrub encroachment. We compared lizard community structure on 21 areas treated with herbicide from 7 to 29 years ago with paired untreated areas that were dominated by shrubs and matched by geomorphology, soils, and elevation. To examine mechanisms underlying responses to restoration, we tested whether the abundance of a grassland specialist, Aspidoscelis uniparens, depended on time since treatment, treatment area and isolation, and local habitat quality. Because lizards use rodent burrows as habitat, we tested whether community structure and A. uniparens abundance depended on the abundance of the keystone rodent, Dipodomys spectabilis. Treated areas had reduced shrub cover and increased grass cover compared to untreated areas. Lizard community composition differed strongly between areas, with four species responding to treatments. Divergence in community composition between treated–untreated pairs was greatest for old treatments (≥22 years), and community composition was influenced by D. spectabilis. In particular, the abundance of A. uniparens was greatest on old treatments with a high density of D. spectabilis. Overall, our results demonstrate lizard community structure responds to grassland restoration efforts, and keystone species can shape restoration outcomes. Reestablishment of keystone species may be a critical constraint on the recovery of animal biodiversity after habitat restoration.