State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, 210008 Nanjing, PR China; University of Chinese Academy of Sciences, 100049 Beijing, PR China.
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, 210008 Nanjing, PR China.
Sci Total Environ. 2018 Dec 1;643:312-323. doi: 10.1016/j.scitotenv.2018.06.203. Epub 2018 Jun 22.
Aquatic plants in shallow freshwater lakes play a key role in stabilizing ecological function and providing valuable ecosystem services, yet they are severely degraded worldwide. An improved understanding of long-term aquatic plant succession is critical to investigate the potential driving mechanisms and to facilitate ecological restoration. In this paper, we reconstructed changes in the aquatic plant community over the past century based on palynological records from Changdang Lake, Middle and Lower Yangtze River Basin (MLYB), China. Our results reveal that aquatic plants in Changdang Lake have undergone three clear phases: emergent macrophytes dominated the aquatic vegetation in the 1900s-1970s, submerged macrophytes in the 1970s-1990s, and floating macrophytes increasingly after the 1990s. Significant changes in the aquatic plant communities were caused by increasing anthropogenic pressures, such as damming and nutrient loading from agriculture, aquaculture, and urbanization after the Chinese economic reform. We argue that Changdang Lake is currently in a transition phase between a macrophyte-dominated state and an algae-dominated state. Our palynological record is different from many contemporary studies, which suggest submerged plants dominated most lakes in this region before the 1950s. We suggest that the return of the aquatic plants to their 1970s-1980s state would be a realistic target for lake restoration. Our results show that palynological records can reveal long-term dynamics of macrophytes in shallow lakes for sustainable lake restoration and management.
浅水湖泊中的水生植物在稳定生态功能和提供有价值的生态系统服务方面发挥着关键作用，但它们在全球范围内严重退化。深入了解长期水生植物演替对于研究潜在驱动机制和促进生态恢复至关重要。在本文中，我们基于中国长江中下游长荡湖的孢粉记录，重建了过去一个世纪水生植物群落的变化。我们的结果表明，长荡湖的水生植物经历了三个明显的阶段：1900 年代至 1970 年代，挺水植物占水生植被的主导地位；1970 年代至 1990 年代，沉水植物占主导地位；1990 年代以后，浮叶植物逐渐增加。水生植物群落的显著变化是由人类活动压力增加引起的，例如中国经济改革后大坝建设和农业、水产养殖和城市化带来的养分负荷。我们认为，长荡湖目前正处于由大型植物主导的状态向藻类主导的状态过渡的阶段。我们的孢粉记录与许多当代研究不同，这些研究表明，在 1950 年代之前，该地区的大多数湖泊以沉水植物为主。我们认为，水生植物恢复到 1970 年代至 1980 年代的状态将是湖泊恢复的现实目标。我们的研究结果表明，孢粉记录可以揭示浅水湖泊中大型植物的长期动态，以实现可持续的湖泊恢复和管理。
