Biodiversity studies might help to understand the ecological dynamics of regions under the influence of upwelling and serve as a baseline to conservation and management strategies. Here, we evaluated the alpha (species richness and Shannon-Wienner index – H’) and beta (Bray Curtis index) diversities of a Brachyura assemblage within a depth gradient (5, 10, 15, 25, 35, and 45 m) in the Macaé region, State of Rio de Janeiro, Brazil. A total of 1,221 decapod individuals were sampled, comprising 11 species .The highest diversity index was recorded at 5 m in depth and the lowest at 25 m. The ecological indexes (diversity and evenness indexes) were inversely proportional to the organic matter and phi (sediment texture). This finding suggests that the heterogeneous sediment of shallow areas increases habitat complexity, therefore increasing biodiversity. Since the study area is an upwelling zone, the coastal area is more affected by cold-water masses, leading to a distinct biodiversity distribution when compared with regions that are not under the influence of upwelling. Considering these peculiarities, the importance of coastal areas to the biodiversity of regions affected by upwelling becomes evident. Such areas must have differential importance when conducting environmental conservation and management projects.

中文翻译：

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brachyuran 蟹的测深分布：上升流区域的 Alpha 和 Beta 多样性变化

生物多样性研究可能有助于了解受上升流影响的地区的生态动态，并作为保护和管理策略的基线。在这里，我们评估了深度梯度（5、10、15、25、35 和 45 m）内 Brachyura 组合的 alpha（物种丰富度和香农-维纳指数 - H'）和 beta（布雷柯蒂斯指数）多样性巴西里约热内卢州马卡埃地区。共采样1221个十足目个体，包括11个物种。多样性指数在5 m处最高，在25 m处最低。生态指标（多样性和均匀度指标）与有机质和phi（沉积物质地）成反比。这一发现表明浅层地区的异质沉积物增加了栖息地的复杂性，从而增加了生物多样性。由于研究区为上升流带，沿海地区受冷水团影响较大，与不受上升流影响的地区相比，生物多样性分布明显。考虑到这些特点，沿海地区对受上升流影响地区生物多样性的重要性变得显而易见。在开展环境保护和管理项目时，这些地区必须具有不同的重要性。