黄河三角洲典型潮沟系统水文连通性对大型底栖动物群落结构的影响

潮沟系统水文连通是滨海湿地的关键生态过程,也是维护和修复滨海湿地的重要途径。了解水文连通性如何影响生物在生境之间的扩散潜力,对于恢复和维持区域和局地生物多样性至关重要。分别于2021年春季（5月）和秋季（10月）对黄河三角洲湿地三条水文连通梯度明显的潮沟进行野外调查和原位观测,探讨不同水文连通梯度下大型底栖动物群落的时空变化特征及其影响因素。结果表明：调查共采集大型底栖动物50种,隶属4门8纲39科45属,包括环节动物23种、软体动物18种、节肢动物5种和纽形动物1种;大型底栖动物群落密度、生物量和多样性指数春季高于秋季,春季以体型小、适应能力较强的软甲类、多毛类和双壳类为主,秋季以活动能力较强的甲壳类、腹足类为主;大型底栖动物群落物种数、密度及生物量和多样性随水文连通性的升高有升高趋势,最高值出现在中等水文连通区域。研究表明潮沟系统水文连通性对大型底栖动物的栖息生境和群落结构及多样性均具有明显的影响,但群落结构及多样性随水文连通梯度的变动规律在季节间存在差异。研究结果有助于进一步了解滨海湿地水文连通对生物群落的影响机制,并为湿地环境保护和修复提供一定科学依据。

Influence of hydrological connectivity of typical tidal creek system on macrobenthos community structure in the Yellow River Delta

The hydrological connectivity of tidal creek system is a key ecological process of coastal wetlands, and also an important way to maintain and repair coastal wetlands. Understanding how hydrological connectivity affects the diffusion potential of organisms between habitats is crucial for restoring and maintaining regional and local biodiversity. In this study, the field investigation and in-situ observation were conducted on three tidal gully with obviously hydrological connectivity gradient in the Yellow River Delta wetland in spring (May) and autumn (October) of 2021, respectively. We aimed to explore the spatial-temporal variation characteristics of macrobenthic community and their influencing factors under different hydrological connectivity gradients. The results showed that a total of 50 species of macrobenthos were collected, belonging to 4 phyla, 8 classes, 39 families and 45 genera, including 23 species of annelids, 23 species of Annelida, 18 species of Mollusca, 5 species of Arthropoda and 1 species of Nemertina. The community density, biomass and diversity index of macrobenthos were higher in spring than in autumn. In spring, Malacostraca, Polychaeta and Bivalvia with small size and strong adaptability were dominant, while in autumn, Crustacea and Gastropoda with strong activity were dominant. The species number, density, biomass and diversity of macrobenthic community tended to increase with the increase of hydrological connectivity, and the highest value appeared in the medium hydrological connectivity area. The study showed that the hydrological connectivity of the tidal creek system had significant effects on the habitat, community structure and diversity of macrobenthos, but the variation pattern of community structure and diversity with the gradient of hydrological connectivity existed the seasonal differences. This study will help to further understand the mechanism of hydrological connectivity of coastal wetlands on biological communities, and provide a scientific basis for wetland environmental protection and restoration.