Mitigation of hydropower—ecosystem conflict in China

Introduction

Renewable energy has long been recognized as a strategic tool for combating global climate change and achieving carbon neutrality (Xia et al., 2023). As an important part of efforts to boost renewable energy transition, hydropower is one of the most mature, economical, and sustainable energy sources with a huge potential to reduce reliance on fossil energy and cope with global climate change, contributing two-thirds of global electricity generation from all renewable sources combined (IEA, 2018). However, there is no such thing as a free lunch, and like any other energy source, hydropower facilities can sometimes emit more carbon emissions than other generators burning fossil fuels (Ocko and Hamburg, 2019). In addition, hydropower projects are likely to come with their own set of unique risks. For example, hydropower exploitation could alter natural streamflow regimes, leading to trade-offs between hydropower benefits and ecosystem services (Zhong et al., 2021). This may threaten regional sustainable ecosystem, and can even result in the loss of ecosystem services in terrestrial and freshwater (Anderson et al., 2018). In particular, such negative impacts can be further exacerbated by climate change. Under the Paris Agreement, countries have pledged to deploy an additional 110 GW of cumulative hydropower capacity by 2030, which could further exacerbate the risks posed by hydropower.

Hydropower exploitation and ecosystem risks in China

China has abundant exploitable hydropower resources and has experienced an unprecedented boom in hydropower development. Historical data show that China’s hydropower deployment has demonstrated a consistent ability to grow over the past several decades, making great efforts, and achieving success to curb its huge carbon emissions. Meanwhile, hydropower, as the largest renewable power in China, plays an irreplaceable role in supporting the country’s sustainable development and contributes to its national energy security. By the end of 2022, China’s cumulative installed hydropower capacity was 413 million kilowatts (including 0.45 billion kilowatts of pumped storage), accounting for 34.05% of the cumulative installed capacity of renewable energy power generation in China. In 2022, China’s hydropower generation was 1.35 trillion kWh, accounting for 50% of renewable energy generation (National Energy Administration, 2023). Current trajectories suggests that China’s hydropower has an exciting prospect, with continued growth in installed capacity and generation in the future. Although hydropower has received widespread attention for its clean power generation and comprehensive benefits, an increasing number of studies are indicating that further expansion of large-scale hydropower in China will be challenging with significant negative effects on the environment such as geological disaster, ecosystem damage, and environmental pollution (Zhang et al., 2021). Many of these effects will be long-lasting, if not irreversible. Enthusiasm for hydropower can not ignore its ecosystem impacts.

By 2017, 24,100 small hydropower stations had been built in 10 provinces of the Yangtze River Economic Belt. Among them, 930 small hydropower stations were constructed without environmental impact assessment, 78 small hydropower stations were built after the nature reserves were demarcated. As a result, the over-exploitation of small-scale hydropower in the Yangtze River Economic Belt caused 333 rivers to be cut off in varying degrees, totaling a length of 1017 km (National Audit Office of the People’s Republic of China, 2018). Worse still, China constructed 25 giant hydropower stations within 100 km of one another on the Jinsha River which pose significant risks to local hydrology, geology, and ecology (Miao, 2014). In addition, China’s hydropower increased threats to the survival of some endangered species by failing to consider the cascading effects of dam construction, such as Chinese sturgeon (Acipenser sinensis) (Zhou et al., 2020), green peafowl (Pavo muticus) (Tang et al., 2019) and Asian elephants (Elephas maximus L.) (Wang et al., 2020). These species are an important component of China’s biodiversity. But they experienced massive population declines and were even on their way to extinction, with habitat fragmentation caused by dams and their associated reservoirs construction threatening the last remaining refuge for these species (Tong, 2022). For example, the number of wild Chinese sturgeon in the Yangtze River decreased from more than 10,000 in the 1970s to 57 by 2010 as a result of hydropower construction (Zhou et al., 2020). On the basis of this scientific record, and early evidence, we must realize that the urgency of acting to mitigate hydropower -ecosystem conflict in China, is real and cannot be ignored.

Thankfully, national policies issued made some strides in alleviating the ecological impacts of hydropower construction. With the realization of ecological sustainability, China launched hydropower rectification plans in 2018, and withdrew more than 3500 small hydropower stations in the Yangtze River Economic Belt by the end of 2020, especially those located in nature reserves that seriously damaged the regional environment and ecosystem. Additionally, in 2020, China also formulated plans to clean up and rectify the outstanding problems of small hydropower in the Yellow River Basin (The State Council of the People’s Republic of China, 2021a). The above actions effectively alleviated hydropower-ecosystem conflict in China, but we need additional strategies and actions.

Conflict-mitigation strategies and practices in China

China regards climate change as a national strategy. In 2021, China made the much-lauded commitment to achieve achieve peak carbon dioxide emissions by 2030 and carbon neutrality by 2060. To realize its climate ambitions, China is implementing ambitious energy transition plans (Hepburn, 2021; Shi et al., 2021). As planned in 2021, China will install approximately 80 GW of additional hydropower capacity by 2030, and build hydropower bases on the upper Jinsha River, the upper Lancang River, the middle section of the Yalong River, and the upper Yellow River, as part of efforts to achieve the national climate goals (The State Council of the People’s Republic of China, 2021b). However, some hydropower bases are located on the Tibetan plateau, which is the key eco-safety barrier in China and Asia with a unique environmental-ecological system. The negative effects on the ecosystem caused by hydropower are enormous and long-lasting. To ensure China’s hydropower construction does not deviate from climate targets, we propose it is necessary to undertake multiple mitigation strategies to ensure ecologically responsible hydropower, properly balance hydropower development and ecological conservation in China.

First, China should improve the standard of planning and evaluation for hydropower projects, and fully consider the optimal number and geographic configuration of dams, as well as their contribution to decarbonization. Second, environmentally friendly hydropower and ecological flow monitoring systems of dams should be supported under the financial, tax and ecological compensation policies, which is an important step for mitigating hydropower-ecosystem conflict. Third, the government needs to invest in additional biodiversity monitoring and databases construction in the reservoir area, and conduct in-depth assessment of cumulative and synergistic ecosystem impacts of dam construction, operation and decommissioning. If the ecosystem is adversely affected, China should adopt management practices such as ecological restoration to minimize them. In the meantime, the government should also build coordinated governance mechanisms for hydropower and eco-environment across basins. Also, social supervision by environmental NGOs should be encouraged. These improvements will be conducive to achieving maximum hydropower benefits with minimum ecological costs.

In addition, the ecosystem impact assessments of hydropower should take into consideration the immeasurable scientific, ecological, cultural, and economic value of endangered species. Failing to do so could turn the development of hydropower projects into another example of extractivist development, which would generating irreversible impacts to the local environment. Finally, “harmonious but different” management strategies for hydropower should be designed and adopted, that fully consider local development realities.

The mitigation of conflicts between hydropower and ecosystems is a pressing issue of high relevance to human society, and it is critical to adopt a science-based interdisciplinary research approach. Researchers must combine energy science, carbon neutrality and innovative research results from related disciplines (including hydrology, sociology, ecological science, and environmental science) to achieve an effective transition to a sustainable future for hydropower. Such interdisciplinary analysis, dynamic and integrated approaches are vital for mitigating hydropower-ecosystem conflicts (Sun et al., 2021), not only in diagnosing problems but also in designing sustainable solutions.

In conclusion, all these conflict-mitigation strategies and practices are integral, compared with the price of damaging ecosystems. By fully and effectively implementing these multiple mitigation strategies, China can maximize the potential benefits of hydropower.