Thresholds in forest bird communities along woody vegetation gradients in the South American Dry Chaco
Thresholds in forest bird communities along woody vegetation gradients in the South American Dry Chaco
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南美干查科地区木本植被梯度森林鸟类群落的阈值
DOI：
10.1111/1365-2664.13342
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发表时间：
2019
影响因子：
5.7
通讯作者：
Kuemmerle
中科院分区：
文献类型：
--
作者：
Macchi L;Baumann M;Bluhm H;Baker M;Levers C;Grau H.R;Kuemmerle
在世界范围内，热带稀树草原和干燥森林正面临着越来越大的土地使用压力。农业向这些生态系统的扩张对环境的影响受到了广泛关注，但自然植被的微妙变化仍然严重不足study.We探讨了鸟类群落如何变化沿着梯度的木本植被在南美干查科结合高分辨率，卫星为基础的树木，灌木和总木本覆盖率与实地数据的频率82种鸟类在167个地块。我们确定了变化点沿着木本覆盖梯度，个别鸟类的相对频率下降最强烈。在此基础上，我们确定了森林指示物种，并评估了群落水平阈值的证据。大多数森林鸟类（71%）在沿着植被梯度的频率上有明显的变化点，从高达38%的总木本覆盖开始。许多（41%）森林物种在木本覆盖率低于11%时急剧减少。乔木和灌木覆盖的一般模式是相似的。我们的研究区域只有7%的树木覆盖水平，我们没有发现森林鸟类群落的反应。相比之下，68%的地区有木本覆盖水平与森林鸟类物种的增量下降，和25%的研究区域的木本覆盖水平低于森林鸟类群落threshold.We确定了11个指标物种密切相关的木本覆盖，在东部和西部干查科的频率最高。这些物种的空间分布与木本植被阈值以上和阈值以下的区域有很好的对应关系。我们发现的证据表明，森林鸟类的关键阈值沿着木本覆盖梯度在干燥的森林和实施的工具，以映射这些阈值已被越过。对于查科，我们强调了保持木质覆盖水平高于40%的重要性，例如在某些比其他形式的农业更有利于野生动物的森林牧场系统中。我们确定了可能完整的森林鸟类群落的剩余区域。更广泛地说，这项研究强调了结合物种水平（指示物种的分布）和生态系统水平（基于卫星的，连续的木本覆盖地图）的替代品，以了解生物多样性模式和威胁的价值。
World‐wide, tropical savannas and dry forests are under increasing pressure from land use. The environmental impacts of agricultural expansion into these ecosystems have received much attention, yet subtler changes in natural vegetation remain severely understudied.We explored how bird communities vary along gradients of woody vegetation in the South American Dry Chaco by combining high‐resolution, satellite‐based tree, shrub and total woody cover with field data on the frequency of 82 bird species surveyed in 167 plots. We identified change points along woody cover gradients where the relative frequency of individual bird species dropped most strongly. Based on this, we identified forest indicator species and assessed evidence for community‐level thresholds.Most forest birds (71%) had clear change points in their frequencies along vegetation gradients, starting as high as 38% total woody cover. Many (41%) forest species declined drastically at woody cover levels of less than 11%. This general pattern was similar for tree and shrub cover.Only 7% of our study area had woody cover levels where we detected no response in forest bird communities. In contrast, 68% of the area had woody cover levels with incremental declines in forest bird species, and 25% of the study area had woody cover levels below the forest bird community threshold.We identified 11 indicator species strongly related to woody cover, with highest frequencies in the eastern and western Dry Chaco. Spatial distributions of these species corresponded well with areas above and below woody vegetation thresholds.Synthesis and applications. We found evidence for critical thresholds for forest birds along woody cover gradients in dry forests and implemented tools to map where these thresholds have been crossed. For the Chaco, we highlight the importance of maintaining woody cover levels above about 40%, such as in certain silvopastoral systems that can be much more wildlife‐friendly than other forms of agriculture. We identify remaining areas of potentially intact forest bird communities. More broadly, this study highlights the value of combining species‐level (indicator species' distributions) and ecosystem‐level (satellite‐based, continuous woody cover maps) surrogates for understanding biodiversity patterns and threats.
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影响因子：
6.1
作者：
J. Wiens;J. Rotenberry
通讯作者：
J. Wiens;J. Rotenberry
微调水果追踪假说：安第斯山森林中水果供应与鸟类水果消费之间的时空联系。
DOI：
10.1111/j.1365-2656.2012.02011.x
发表时间：
2012
期刊：
The Journal of animal ecology
影响因子：
--
作者：
P. G. Blendinger;R. A. Ruggera;M. G. Núñez Montellano;L. Macchi;P. Zelaya;M. Alvarez;E. Martín;Oriana Osinaga Acosta;R. Sanchez;Josefina Haedo
通讯作者：
Josefina Haedo
影响因子：
5.7
作者：
Asunción Semper-Pascual;L. Macchi;F. Sabatini;Julieta Decarre;Matthias Baumann;P. G. Blendinger;B. Gómez-Valencia;Matías E. Mastrángelo;T. Kuemmerle
通讯作者：
Asunción Semper-Pascual;L. Macchi;F. Sabatini;Julieta Decarre;Matthias Baumann;P. G. Blendinger;B. Gómez-Valencia;Matías E. Mastrángelo;T. Kuemmerle
影响因子：
6.3
作者：
Caro, TM;O'Doherty, G
通讯作者：
O'Doherty, G
影响因子：
2.7
作者：
Suarez-Rubio M;Lookingbill TR
通讯作者：
Lookingbill TR