厦门海域蟹类资源的变化

本研究依据2006—2007年与2016—2017年各个季节在厦门海域采样获得的蟹类样品数据，对比分析了其种类组成、资源密度及其多样性指数。结果表明：厦门海域蟹类的种类组成有较大变化，种类更替率为55.32%,伴随着在两次调查中扇蟹科、方蟹科和关公蟹科等物种的新出现及梭子蟹科和长脚蟹科物种的消失，同时蟹类丰度(d)有所减少；均匀度(J)、种类多样性指数(H′)和资源密度变化较小；蟹类的群落结构变得更单一，容易遭到破坏；研究期间拟穴青蟹(Scylla paramamosain)资源出现一定程度的恢复，蟹类资源的平均个体质量有所增加，其中秋季蟹类个数密度增长较为明显。本研究建议在保证严格禁渔等管理的同时，加强对其海洋栖息地的管理和恢复。

Study on the changes of crab stocks in Xiamen sea areas

In this study, species composition, stocks density and diversity index were compared and analyzed based on crab samples collected from Xiamen sea areas in seasons from 2006 to 2007 and 2016 to 2017. Results showed that, species composition of crabs in Xiamen sea areas had significantly changes, with a species replacement as high as 55.32%. Along with the presence of some species such as Xanthidae, Grapsidae and Dorippidae, and the absence of some species in Portunidaeand and Goneplacidae, the crab abundance decreased. However, the changes of evenness, diversity index and density were insignificant. The community structure of crabs became simplified. The average weight of individual crabs had increased during the study period, and there was a certain degree of Scylla paramamosain stock recovery during surveys, particularly with a significant increase of crab density in autumn. This study recommends strengthening the management and restoration of marine habitat with measurement such as fishing bans.