Wang Yongzhi, Ji Xianglin, Zhou Lizhi
School of Resources and Environmental Engineering Anhui University Hefei China.
Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration (Anhui University) Hefei China.
Ecol Evol. 2024 Oct 7;14(10):e70222. doi: 10.1002/ece3.70222. eCollection 2024 Oct.
Gate-controlled activities in lakes can directly or indirectly influence the assembly of waterbird communities. Shengjin Lake, a Ramsar site, is a typical river-connected and gate-controlled shallow lake in the lower and middle Yangtze River floodplain in China, comprising three sub-lakes (upper, middle, and lower) based on topographical features. We surveyed wintering waterbirds at Shengjin Lake from October 2022 to March 2023. We divided the winter water level period into nine phases based on the characteristics of water level changes. By measuring functional diversity, we aimed to provide insights into the differences in waterbird communities among the three sub-lakes under different water level conditions. Multiple linear regression was used to analyze the relationship between habitat factors and functional diversity. We further explored the relationship between specific functional traits and habitat factors through a combination of the R-mode linked to the Q-mode and the trait-environment correlation matrix (fourth-corner analyses) to explain the mechanism underlying waterbird community assembly. When the water level fluctuated in the range of 10.43-10.74 m (Huanghai elevation), the three sub-lakes had significant habitat differences and high habitat heterogeneity, increasing functional richness and functional dispersion of the upper and lower lakes, both of which significantly differed from those of the middle lake. Habitat heterogeneity and mudflat habitats have positive effects on functional diversity. The difference in functional diversity was primarily determined based on the foraging traits and strata of waterbirds. Habitat filtering of particular traits is a major driving force underlying the assembly of waterbird communities. Overall, we suggest that the minimum water level in the wintering period at Shengjin Lake should be regulated between 10.43 and 10.74 m. These findings provide reasonable suggestions for water level regulation and a theoretical basis for conserving waterbird diversity at Shengjin Lake.
湖泊中的闸门控制活动可直接或间接影响水鸟群落的组成。升金湖是一处拉姆萨尔湿地，是中国长江中下游平原典型的通江且受闸门控制的浅水湖泊，根据地形特征可分为三个子湖（上湖、中湖和下湖）。我们于2022年10月至2023年3月对升金湖的越冬水鸟进行了调查。根据水位变化特征，我们将冬季水位期划分为九个阶段。通过测量功能多样性，我们旨在深入了解不同水位条件下三个子湖之间水鸟群落的差异。采用多元线性回归分析栖息地因素与功能多样性之间的关系。我们还通过将R模式与Q模式相联系以及性状-环境相关矩阵（第四角分析）相结合的方法，进一步探究特定功能性状与栖息地因素之间的关系，以解释水鸟群落组成的潜在机制。当水位在黄海高程10.43 - 10.74米范围内波动时，三个子湖具有显著的栖息地差异和高栖息地异质性，上湖和下湖的功能丰富度和功能离散度增加，且这两者均与中湖有显著差异。栖息地异质性和泥滩栖息地对功能多样性有积极影响。功能多样性的差异主要基于水鸟的觅食性状和水层来确定。特定性状的栖息地筛选是水鸟群落组成的主要驱动力。总体而言，我们建议将升金湖越冬期的最低水位调控在10.43至10.74米之间。这些研究结果为水位调控提供了合理建议，并为升金湖水鸟多样性保护提供了理论依据。
