Ren Wenjing, Yao Yiqian, Gao Xiaoyu, Wang Hao, Wen Zihao, Ni Leyi, Zhang Xiaolin, Cao Te, Chou Qingchuan
State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China.
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
Front Plant Sci. 2024 May 17;15:1375898. doi: 10.3389/fpls.2024.1375898. eCollection 2024.
Water depth (WD) and snail abundance (SA) are two key factors affecting the growth of submersed aquatic plants in freshwater lake ecosystems. Changes in WD and SA drive changes in nutrients and other primary producers that may have direct or indirect effects on submersed plant growth, but which factor dominates the impact of both on aquatic plants has not been fully studied.
To investigate the dominant factors that influence aquatic plant growth in plateau lakes, a one-year field study was conducted to study the growth of three dominant submersed macrophyte (i.e., , , and ) in Erhai Lake.
The results show that, the biomass of the three dominant plants, , is the highest, followed by , and is the lowest. Meanwhile, periphyton and snails attached to are also the highest. Furthermore, WD had a positive effect on the biomass of two submersed macrophyte species of canopy-type and , while it had a negative effect on rosette-type Snail directly inhibited periphyton attached on and thereby increasing the biomass of aquatic plants, but the effect of snails on the biomass of the other two aquatic plants is not through inhibition of periphyton attached to their plants.
The dominant factors affecting the biomass of submersed macrophyte in Erhai Lake were determined, as well as the direct and indirect mechanisms of WD and snails on the biomass of dominant submersed macrophyte. Understanding the mechanisms that dominate aquatic plant change will have implications for lake management and restoration.
水深（WD）和螺蛳丰度（SA）是影响淡水湖泊生态系统中沉水水生植物生长的两个关键因素。水深和螺蛳丰度的变化驱动着养分及其他初级生产者的变化，这可能对沉水植物生长产生直接或间接影响，但关于这两个因素中哪个对水生植物的影响占主导地位尚未得到充分研究。
为研究影响高原湖泊水生植物生长的主导因素，开展了为期一年的实地研究，以研究洱海三种优势沉水大型植物（即 、 和 ）的生长情况。
结果表明，三种优势植物 、 、 的生物量中， 最高，其次是 ， 最低。同时，附着在 上的周丛生物和螺蛳也最多。此外，水深对冠层型的两种沉水大型植物 和 的生物量有积极影响，而对莲座型的 有负面影响。螺蛳直接抑制附着在 上的周丛生物，从而增加水生植物的生物量，但螺蛳对其他两种水生植物生物量的影响并非通过抑制附着在其植株上的周丛生物来实现。
确定了影响洱海沉水大型植物生物量的主导因素，以及水深和螺蛳对优势沉水大型植物生物量的直接和间接作用机制。了解主导水生植物变化的机制将对湖泊管理和恢复具有重要意义。
