Data from: Robustness of habitat-based surrogates of animal diversity: a multi-taxa comparison over time

Many animal taxa respond strongly to spatial and temporal variation in vegetation structure and floristic composition, suggesting that changes in vegetation could be a cheap and readily observable surrogate for changes in animal assemblages. Yet there is considerable uncertainty about how different taxa respond to vegetation over time, potentially limiting the application of habitat-based surrogates to many areas of applied ecology. We examined the strength and temporal consistency of habitat-based surrogates of three different vertebrate taxa in a landscape with multiple vegetation types. We used regression models to quantify the relationships between six vegetation attributes (species richness and percentage cover of overstorey, midstorey and understorey) and three measures of bird, mammal and reptile assemblages (abundance, species richness and composition). We found that overstorey richness and cover had both consistent and strong positive effects on bird assemblages. Vegetation effects were generally weaker and more variable for mammals and reptiles compared with birds. Each taxon displayed different temporal dynamics following fire, with negative effects on birds and mammals, but positive short-term effects on reptiles. Surprisingly, fire increased vegetation effects on birds, but did not consistently alter vegetation effects on mammals or reptiles, indicating a lack of concordant responses among taxa. Synthesis and applications. Empirical testing of habitat-based surrogates of multiple animal taxa is needed to identify reliable and consistent management proxies. Our study suggests that habitat-based surrogates could be useful metrics for quantifying changes in bird assemblages through time and after fire, but that the same metrics could not be applied to mammal and reptile assemblages. The absence of both strong and consistent effects of vegetation attributes across the three groups of vertebrates suggests that taxon-specific habitat surrogates may be required to detect changes over time and after disturbance within heterogeneous landscapes.

众多动物类群（animal taxa）对植被结构（vegetation structure）与植物区系组成（floristic composition）的空间、时间变异响应显著，这提示植被变化可作为低成本且易观测的替代指标（surrogate），用以表征动物群落（animal assemblages）的变化。然而，不同类群随时间对植被的响应机制仍存在诸多不确定性，这可能限制了基于生境的替代指标在诸多应用生态学（applied ecology）领域的应用。
本研究在包含多种植被类型的景观中，探究了三类不同脊椎动物类群（vertebrate taxa）的生境替代指标的有效性及其时间一致性。我们通过回归模型（regression models）量化了六项植被属性：乔木层（overstorey）、中层植被（midstorey）与下层植被（understorey）的物种丰富度（species richness）及盖度（percentage cover），与鸟类、哺乳类、爬行类三类脊椎动物的三项群落指标——多度（abundance）、物种丰富度与群落组成（composition）——之间的关联。
研究发现，乔木层的物种丰富度与盖度对鸟类群落存在一致且强烈的正向影响。相较于鸟类，哺乳类与爬行类的植被响应普遍更弱且变异性更高。三类群在火灾（fire）后展现出不同的时间动态（temporal dynamics）：鸟类与哺乳类受到负面影响，而爬行类则呈现短期正向响应。出乎意料的是，火灾增强了植被对鸟类群落的影响，但并未始终改变植被对哺乳类与爬行类的影响，这表明不同类群间缺乏协同响应（concordant responses）。
总结与应用（Synthesis and Applications）。亟需针对多动物类群的生境替代指标开展实证检验，以识别可靠且一致的管理替代指标（management proxies）。本研究表明，基于生境的替代指标可作为量化鸟类群落随时间及火灾后变化的有效指标，但此类指标无法直接应用于哺乳类与爬行类群落。在异质景观（heterogeneous landscapes）中，三类脊椎动物类群均未表现出一致且强烈的植被属性响应，这提示若要检测扰动后或随时间的群落变化，可能需要针对特定类群的生境替代指标。