【摘要】 元江是发源于云南省的一条重要国际河流，海拔跨度大，其沿岸带水生植物资源现状尚不明确。为探究雨季初、末期水生植物群落分布特征及其主要环境驱动因子，本研究于2024年雨季初期(6月)和末期(9月)对元江进行了野外调查。共记录到水生植物77种，隶属26科66属，其中雨季末期的物种数较初期显著减少。生活型以挺水(含湿生)植物为主(70种),漂浮、沉水和浮叶植物分别仅有4种、2种和1种。群落生物量鲜重范围为195.6～2 257.3 g/m~2,平均为865.9 g/m~2。群落α多样性方面，Shannon-Wiener指数(H’)均值为1.29(范围0.43～1.86),Pielou均匀度指数(J)均值为0.80(范围0.31～0.98)。β多样性中，S?renson相似性指数(Cs)均值为0.36(范围0.18～0.56),Cody差异性指数(βc)均值为7.9(范围3.0～16.5)。回归分析显示，雨季初、末期H′随海拔升高均呈显著单峰变化趋势(P<0.05)。雨季初期，Cs随海拔单调下降(P=0.038),βc则呈单峰变化(P=0.007);至雨季末期，海拔梯度效应减弱，β多样性指数趋同。冗余分析进一步表明，随雨季进程，河宽、水体总氮和盐度等环境因子共同作用，削弱了海拔梯度的影响，成为水生植物多样性格局的协同驱动因素。本研究可为元江流域水生态保护与可持续管理提供科学依据。[中国渔业质量与标准，2025,15(3):20-31]更多还原

【Abstract】 The Yuanjiang River, a major international waterway originating in Yunnan Province, China, exhibits a significant elevational gradient. However, the status of aquatic plant resources in its riparian zones remains poorly understood. To investigate the distribution patterns of aquatic plant communities and their primary environmental drivers during different phases of the rainy season, field surveys were conducted in June(early rainy season) and September(late rainy season) of 2024. A total of 77 aquatic plant species from 66 genera and 26 families were recorded, showing a notable decrease in species richness by the late rainy season. Emergent(including hygrophytic) plants dominated the life-form spectrum(70 species), while only four free-floating, two submerged, and one floating-leaved species were found. Fresh biomass of the communities ranged from 195.6 to 2 257.3 g/m~2, with a mean of 865.9 g/m~2. In terms of α-diversity, the mean Shannon-Wiener index(H′) was 1.29(range: 0.43-1.86), and the mean Pielou’s evenness index(J) was 0.80(range: 0.31-0.98). For β-diversity, the mean S?renson similarity index(Cs) was 0.36(range: 0.18-0.56), and the mean Cody dissimilarity index(βc) was 7.9(range: 3.0-16.5). Regression analyses indicated that H′ exhibited a significant unimodal relationship with elevation during both the early and late rainy seasons(P<0.05). In the early rainy season, Cs decreased monotonically with elevation(P=0.038), whereas βc showed a unimodal trend(P=0.007). By the late rainy season, elevational effects weakened, and β-diversity indices became more homogeneous. Redundancy analysis further revealed that, as the rainy season progressed, environmental factors such as river width, total nitrogen, and salinity collectively diminished the influence of elevation and acted as synergistic drivers shaping aquatic plant diversity patterns. This study provides a scientific foundation for aquatic ecosystem conservation and sustainable management in the Yuanjiang River Basin.[Chinese Fishery Quality and Standards, 2025,15(3):20-31]更多还原