Decades of research have revealed relationships between the abundance of coral reef taxa and local conditions, especially at small scales. However, a rigorous test of covariation requires a robust dataset collected across wide environmental or experimental gradients. Here, we surveyed spatial variability in the densities of major coral reef functional groups at 122 sites along a 70 km expanse of the leeward, forereef habitat of Curaçao in the southern Caribbean. These data were used to test the degree to which spatial variability in community composition could be predicted based on assumed functional relationships and site-specific anthropogenic, physical, and ecological conditions. In general, models revealed less power to describe the spatial variability of fish biomass than cover of reef builders (R² of best-fit models: 0.25 [fish] and 0.64 [reef builders]). The variability in total benthic cover of reef builders was best described by physical (wave exposure and reef relief) and ecological (turf algal height and coral recruit density) predictors. No metric of anthropogenic pressure was related to spatial variation in reef builder cover. In contrast, total fish biomass showed a consistent (albeit weak) association with anthropogenic predictors (fishing and diving pressure). As is typical of most environmental gradients, the spatial patterns of both fish biomass density and reef builder cover were spatially autocorrelated. Residuals from the best-fit model for fish biomass retained a signature of spatial autocorrelation while the best-fit model for reef builder cover removed spatial autocorrelation, thus reinforcing our finding that environmental predictors were better able to describe the spatial variability of reef builders than that of fish biomass. As we seek to understand spatial variability of coral reef communities at the scale of most management units (i.e., at kilometer- to island-scales), distinct and scale-dependent perspectives will be needed when considering different functional groups.

数十年的研究揭示了珊瑚礁类群的丰度与当地条件之间的关系，尤其是在小尺度上。然而，协变的严格测试需要跨广泛的环境或实验梯度收集的稳健数据集。在这里，我们调查了加勒比南部库拉索岛背风前礁栖息地 70 公里范围内 122 个地点的主要珊瑚礁功能群密度的空间变异性。这些数据用于测试基于假定的功能关系和特定地点的人为、物理和生态条件可以预测群落组成的空间变异性的程度。一般来说，模型显示的描述鱼类生物量空间变异性的能力低于珊瑚礁建造者的覆盖率（R ²最佳拟合模型数：0.25 [鱼] 和 0.64 [造礁者]）。造礁者的总底栖覆盖率的变化最好用物理（波浪暴露和珊瑚礁浮雕）和生态（草皮藻类高度和珊瑚新兵密度）预测因子来描述。没有人为压力的度量与造礁者覆盖的空间变化有关。相比之下，鱼类总生物量与人为预测因素（捕鱼和潜水压力）保持一致（尽管较弱）。作为大多数环境梯度的典型特征，鱼类生物量密度和造礁覆盖的空间模式在空间上是自相关的。鱼类生物量最佳拟合模型的残差保留了空间自相关的特征，而珊瑚礁建造者覆盖的最佳拟合模型去除了空间自相关，因此加强了我们的发现，即环境预测因子能够比鱼类生物量更好地描述造礁者的空间变异性。当我们试图了解大多数管理单位规模（即千米到岛​​屿规模）珊瑚礁群落的空间变异性时，在考虑不同的功能组时将需要不同的和规模相关的观点。