多视野中的长江口鱼类生物多样性及其在生境驱动下的时空变化

长江口是众多鱼类的三场一通道，具有重要经济和生态地位，研究表明长江口鱼类生物多样性衰退显著，亟需开展全面研究查明长江口鱼类生物多样性及其时空变化为资源保护提供依据。本项目通过传统资源调查、环境DNA宏条形码技术、早期生活史等多视野结合研究长江口鱼类生物多样性现状；利用组合物种分布模型预判早期生活史阶段鱼类的分布及最适生境变化，预测长江口产卵场和育幼场及鱼类多样性的未来变化；结合长时间鱼类和生境数据，通过群落生态学分析探明长江口鱼类生物多样性的时空变化特征及其驱动生境因素。本研究拟解决以下科学问题：多维视野中的长江口鱼类生物多样性怎样？未来早期生活史阶段长江口鱼类的分布和最适生境如何变化？历史-当前-未来长江口鱼类生物多样性的时空变化及主导生境因素为何？本项目研究成果对于可持续利用和保护长江口鱼类资源具有重要意义，亦能为生态监测和资源评估及管理政策的制定提供科学基础。

The Yangtze Estuary is of high productivity and rich in bait. It is an important spawning and nursery ground for many commercial fish species such as yellow croaker, ribbonfish and pomfret. And it is also a big important bait field for many species in summer and autumn. At the meanwhile, The Yangtze Estuary is the only migration channel of the endangered species such as Chinese sturgeon, roughskin sculpin, and reeves shad. Thus the Yangtze Estuary occupies an important position in Blue Economy. In recent years, with the environmental changes and human activities, fisheries resources of the Yangtze Estuary seriously decline, and the species and numbers of fisheries resources based on the traditional ecological investigation is decreasing year by year. Therefore, it is urgent to conduct a comprehensive study to identify the fish biodiversity in the Yangtze Estuary and its temporal and spatial variation characteristics in order to provide countermeasures and evidence for its conservation and sustainable use.. The present project studies fish biodiversity in the Yangtze Estuary through a combination of traditional resource surveys, environmental DNA meta-barcoding technology, and early life history stage data. Using climate models and ensemble species distribution models based on ichthyoplankton samples- early life history stage of fishes collected from the project and before, the project could reveal its expected distribution and optimal habitat, and invert the future changes of fish biodiversity in the Yangtze Estuary. Based on the habitat data collected by the project and before, we could find the dominant habitat factors through ecological community analysis, which influence the changes of fish biodiversity in the Yangtze Estuary. . Through the above research, we will answer the following scientific questions: 1) What is the biodiversity of fish in the Yangtze River estuary in a multi-dimensional field of view? 2) How does the distribution and optimum habitat of early life history stage of fishes in the Yangtze Estuary change under climate change? 3) During History-Current-Future, what are the main habitual factors influencing fish biodiversity in the Yangtze Estuary?. The present project is of great importance for living marine resources conservation, sustainable exploitation of fisheries, aquatic products processing industry, environment-friendly development and socio-economic stability. The research results of the project are of great significance for carrying out targeted protection of the Yangtze Estuary's fishery resources, sustainable use and maintaining the "three fields and one channel" function of the Yangtze Estuary.