Chinese scientists: Technology-driven and law-based system key to lake ecosystems, biodiversity protection

“We should integrate our technological resources and build up a sound technological support system, accelerating the building of relevant law & regulation systems for lake protection and management,” Zhang Ganlin, director and researcher of the Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences(CAS), notes in an article released by the Bulletin of Chinese Academy of Sciences (BCAS, in Chinese), a think tank journal supervised and sponsored by the CAS, which focuses on strategic and decision-making research.

Among important land resources and as key geographical units of land surface systems, lakes(including artificial reservoirs) are important surface water resources, and they are also an important part of the earth surface system consisting of “mountains,rivers, forests, farmland, lakes, grassland and sand,” as Zhang points out in his article “Ecological and Environmental Changes and Protection Measures of Lakes in China.” The article also notes that lakes play an irreplaceable role in water resource supply, flood control and drought alleviation, water quality purification, and biodiversity protection.

Given the important roles and significance of lakes in socio-economic development, the article, based on long-term lake research and monitoring data, proposes the strategies for the protection, management, and restoration in response to the problems faced by lake ecosystems in China.

In recent years, the overall condition of the ecological environment of lakes in our country has been becoming better, and the protection to lakes has achieved remarkable results. For example, the water quality of Poyang Lake, which is located in the eastern plains of China has shown a trend of improvement in recent years, and the annual average concentration of total phosphorus, the main pollutant, has declined slightly. From 2012 to 2020, the inter-annual variation of wetland vegetation biomass in Poyang Lake was flat, and the variation range was relatively small. Since 2012, the importance value of the dominant species of the typical plant communities in Poyang Lake wetland have remained above 0.6, showing a relatively stable community structure and playing an important supporting role in the stability of the ecosystem structure and the maintenance of ecological functions in the lake.

The paper also reveals that for the past decades, China has strengthened ecological conservation and environment protection at all times and in all dimensions and regions. Since 2021, China has achieved initial success in the critical battle against water pollution. Major action plans on addressing water pollution have been fully implemented. Also, the country has redoubled efforts to preserve and restore lake ecosystems and protect biodiversity, with the integrated protection and restoration of various ecosystems and implementation of a series of fundamental, pioneering, and long-term programs.

First, a significant increase can be seen in the total amount of available freshwater resources in lakes. There are 2,670 natural lakes over 1 km² of area in China, and 98,600 reservoirs with an increase of 10,100 over 2011. Thanks to the lake protection and water quality improvement, the proportion of centralized drinking water sources from lakes and reservoirs across China has increased from 33% to 40% in the past five years, which serves nearly 50% of the population of the country.

Second, the lakes under priority control have reported steady improvement of water quality. For instance, the “three lakes” (the Taihu Lake, Chaohu Lake and Dianchi Lake), have registered significantly checked eutrophication trend. With the increase in the transparency of about 70% of large and medium-sized lakes in China in the past 10 years, the lakes have become clearer overall.

Third, with the restoration of the aquatic vegetation in lakes and the steady rise in the biodiversity of major lakes, the lakes have reported improvement of ecological service functions. This has been approved by the fact that about 43% and 40% showed a significant improvement of aquatic vegetation between 2010-2014 and between 2015-2019, respectively.

However, China still needs to continue with science and technological innovation in lake ecological environment management and protection. There are significant rooms for development of higher level processing materials, key technologies, and equipment, and relevant basic and applied research.

Therefore, Chinese scientists have put forward several key approaches to exploring the paths to high-quality development for lake watersheds with low resource consumption and environmental costs.

Among all the suggestions, the article attaches great importance to building a technology-driven and law-based system, in an effort to protect lake ecosystems and biodiversity in China.

More efforts should be made to set up sound systems in the following areas: performance evaluation and accountability for ecological conservation, compensation for ecological conservation, designation of river and lake managing chiefs. Meanwhile, corresponding laws and regulations should be further formulated or revised.

The article further explains that it is necessary to strengthen the role of technology in supporting the lake-type ecological environment protection, that is to say, to integrate all possible technological resources and build up a sound technological support system, and vigorously promote the technology-based lake manager system to further enhance the scientific management and protection of lakes.

National legislation for lake protection should also be promoted, accelerating the building of relevant law & regulation systems for lake protection and management and improve the mechanism for the alignment between administrative law enforcement and criminal justice in lake watershed protection.

On the institutional level, it is advised to adopt an “ecological bank” model and improve the compensation system for the ecological benefits of lakes.