AVIAN ASSEMBLAGES IN ALTERED AND NATURAL GRASSLANDS IN THE NORTHERN CAMPOS OF URUGUAY
AVIAN ASSEMBLAGES IN ALTERED AND NATURAL GRASSLANDS IN THE NORTHERN CAMPOS OF URUGUAY
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DOI：
10.1525/cond.2009.080111
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发表时间：
2009-02-01
期刊：
影响因子：
3.1
通讯作者：
Blake, John G.
中科院分区：
文献类型：
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作者：
Azpiroz, Adrian B.;Blake, John G.
栖息地的改变是导致草原鸟类种群数量下降的最重要因素。在这项研究中，我们的特点是在乌拉圭的四个不同的农业计划在耕地和天然草原的鸟类群落。我们调查了鸟类沿着样带，以确定物种丰富度，组成和人口密度沿着这一农业梯度。虽然物种丰富度较低，在最天然的草地类型（24种），社区组成和丰富的模式突出了自然草原的重要性，为保护栖息地专家。相似性分析表明，4种草地类型的鸟类群落具有明显的差异（ANOSIM global R = 0.68）。几个物种利用草地功能的特点是耕地的栖息地，而相反的是真正的草地专性和天然草地。所有的指示种分析进一步支持协会的草地兼性和草地专性鸟类与耕地和天然草地，分别。种群密度模式因物种而异;声波更丰富的耕地栖息地，其他在天然草地，但受威胁的物种达到相对较高的密度，在天然草地。一些受威胁的物种，例如赭色胸Pipit（Anthzus nattereri）和潘帕斯草原草地百灵（Sturnella defilippii），很大程度上仅限于天然草原，因此它们的长期生存将取决于这些栖息地类型的合适斑块的保护。
Alteration of habitat has been highlighted as the most important factor causing declines in populations of grassland birds. In this study we characterized bird assemblages in cultivated and natural grasslands under four different agricultural schemes in Uruguay. We surveyed birds along transects to determine species richness, composition, and population density along this agricultural gradient. Although species richness was lower in the most natural grassland type (24 species), community composition and abundance patterns highlighted the importance of natural grasslands for the conservation of habitat specialists. All analysis of similarity showed that bird communities in the four grassland types were distinct (ANOSIM global R = 0.68). Several species using grassland facultatively were characteristic of cultivated habitats, whereas the opposite was true for grassland obligates and natural grasslands. All indicator-species analysis further supported the association of grassland-facultative and grassland-obligate birds with cultivated and natural grassland, respectively. Population-density patterns varied by species; sonic were more abundant in cultivated habitats, others in natural grasslands but threatened species attained relatively high densities in natural grasslands only. Some threatened species, such as the Ochre-breasted Pipit (Anthzus nattereri) and Pampas Meadowlark (Sturnella defilippii), were largely restricted to natural grasslands, so their long-term survival will depend on the conservation of suitable patches of these habitat types.