Biodiversity has critical phylogenetic and functional components, yet many prior studies of marine communities focus only on taxonomic diversity. Here, we surveyed intertidal crustacean communities across 11 sites in the Puget Sound (Washington state). We calculated taxonomic diversity (Shannon’s H), functional diversity (functional evenness and Rao’s Q), and phylogenetic diversity to examine how these indices were related and how they varied with environmental factors. A model selection approach (AIC) was used to examine which factors (habitat complexity, algal richness, salinity, and urbanization) were the best predictors for each index. Across sites, all four diversity indices were moderately correlated. Algal richness emerged as an important factor, occurring in well-supported models across all diversity indices: sites with more algal species had higher levels of taxonomic, functional, and phylogenetic diversity. Species diversity of both herbivores and non-herbivores was positively correlated with algal species richness, suggesting algae may be important for habitat as well as a food source. More species-rich algal communities had more phylogenetically diverse assemblages of herbivores, but algal richness was not correlated to non-herbivore phylogenetic diversity. Boulder size, but not other measures of habitat complexity, was positively correlated with functional diversity; most diversity in our samples was associated with boulders. Sites adjacent to higher levels of impervious surfaces (e.g., urbanization) had lower values of functional evenness. A growing number of studies have demonstrated that anthropogenic factors can have particularly strong effects on functional or phylogenetic diversity, and our study provides a number of tools for future investigations of crustacean diversity in this region.

生物多样性具有重要的系统发育和功能组成，然而，许多先前对海洋群落的研究仅关注分类学多样性。在这里，我们对普吉特海湾（华盛顿州）的11个地点的潮间带甲壳动物群落进行了调查。我们计算了分类学上的多样性（Shannon's H），功能上的多样性（功能均匀性和Rao's Q）以及系统发育上的多样性，以研究这些指数之间的关系以及它们如何随环境因素而变化。模型选择方法（AIC）用于检查哪些因素（栖息地复杂性，藻类丰富度，盐度和城市化程度）是每个指数的最佳预测因子。在各个站点之间，所有四个多样性指数均具有中等相关性。藻类丰富性已成为一个重要因素，出现在所有多样性指标的良好支持的模型中：藻类种类更多的位点具有更高的分类学，功能和系统发育多样性。食草动物和非食草动物的物种多样性与藻类物种丰富度呈正相关，这表明藻类对于栖息地和食物来源都可能是重要的。更多物种丰富的藻类群落具有更多的食草动物系统发育多样性组合，但藻类丰富度与非草食动物系统发育多样性无关。巨石的大小，而不是其他生境复杂性的衡量标准，与功能多样性呈正相关。我们样本中的大多数多样性都与巨石有关。与较高水平的不透水表面（例如，城市化）相邻的站点的功能均匀性值较低。