Restored and sustainably managed ecosystems can enhance climate change adaptation and mitigation capacity

Climate change is an arduous challenge shared by the global community. In recent years, under the combined influence of human activities and natural factors, the world is experiencing the severe consequences of climate change, characterized by frequent extreme weather and climate events and global warming, with varying degrees of impact on the economy, society and the environment.

The heavy rainstorms in Beijing on July 21, 2012 and in Zhengzhou, Henan province, on July 20, 2021, caused many deaths and large economic losses. In addition to heavy rainfall and flooding, climate change can also cause droughts and heat waves, increasing the risk of hill and forest fires. Furthermore, climate change has varying degrees of impact on land use and food security, and extreme weather creates uncertainty and risks to food production.

Meanwhile, global warming poses a serious threat to the north and south polar regions, leading to a continuous reduction in the extent and thickness of sea ice and a subsequent rise in sea level, which will cause further changes and negative impacts.

China is one of the countries that is most affected by sea level rise and coastal flooding as a large proportion of its population live in low-lying coastal areas. For instance, Guangzhou is the city that faces the highest potential economic losses in the world due to sea level rise and flooding. Without the intervention of climate change policies, increasing greenhouse gas emissions and concentrations will cost the city a loss of $331 billion per year by 2050.

Climate change poses not only social and economic risks and losses, but also grave threats to ecosystems and biodiversity. Fifty-five percent of global GDP is dependent, if not heavily dependent, on biodiversity and ecosystem services. Climate change is causing enormous damage to terrestrial, aquatic, coastal and high seas ecosystems and the losses are difficult to restore, resulting in widespread degradation of ecosystem structure and function, resilience and natural adaptation.

In June 2022, China's National Climate Change Adaptation Strategy 2035 was jointly released by 17 ministries and departments, including the Ministry of Ecology and Environment, the National Development and Reform Commission and the Ministry of Science and Technology, in order to respond to global climate change and coordinate national efforts to tackle this challenge. One of the basic principles of the strategy is scientific adaptation by following the law of nature, which incorporates contents of nature-based solutions (NbS), exploring integration with urban and rural infrastructure construction, and enhancing comprehensive climate change adaptation capacity by effectively promoting ecosystem functions and services, especially in disaster risk reduction, food and water security and biodiversity loss prevention.

NbS is an umbrella concept that summarizes a range of ecosystem-based approaches and practices that preceded the NbS concept and have long had a deep theoretical and practical basis. NbS distinguishes itself from engineering solutions and from nature-derived solutions such as wind and photovoltaic power generation as these solutions do not target the improvement of ecosystems for conservation, let alone enhance and leverage ecosystem functions and services.

As the concept of NbS has emerged and evolved, it has been crucial to give it a science-based and widely-accepted definition. In 2016, at the Sixth International Union for Conservation of Nature World Conservation Congress, the definition and principles of NbS were established. NbS refers to actions to protect, sustainably manage, and restore natural and modified ecosystems in ways that address societal challenges effectively and adaptively, and simultaneously provide both human wellbeing and biodiversity benefits.

As an approach that leverages ecosystem functions and services, NbS actions are often able to create synergies between mitigation and adaptation. For example, for forest ecosystems, climate change can be addressed through afforestation and forest quality enhancement, which enhances carbon sequestration and reduces soil erosion; for wetland and coastal ecosystems, the exposure and vulnerability of coastal communities can be reduced by restoring and protecting ecosystems such as mangroves, while enhancing carbon sequestration as well as wind-breaking and wave dissipation; and in cities, by creating artificial wetlands, rain gardens, sunken green spaces and other facilities to build sponge cities, enhance resilience and reduce the risk and hazard of flooding. NbS approaches that can make contributions to the areas mentioned above include ecological restoration, ecological engineering, area-based conservation, forest landscape restoration, ecosystem-based adaptation and mitigation, ecosystem-based disaster risk reduction, climate adaptation services, nature and green infrastructure development, and ecosystem-based management.

In June 2020, the International Union for Conservation of Nature officially launched the Global Standard for Nature-based Solutions with user guidance, setting out eight criteria and 28 indicators based on eight principles to provide guidance to NbS practitioners and researchers, thus ensuring the legitimacy, inclusiveness and sustainability of NbS approaches and intervention, and laying the foundation for subsequent standard accreditation.

The Climate Adaptation Summit suggested that NbS is a cost-effective approach that benefits the economy, communities, culture, health and nature, has great potential and remains to be developed for climate change adaptation, and that it should be continuously promoted for mainstreaming. Public and private sector synergies should be facilitated, funding sources should be expanded at both policy and commercial levels, and NbS should be adopted in climate change adaptation.

The impact of climate change is increasingly significant, and it is urgent to take proactive action and to promote nature as a response to the challenge. We hope that all parties will work together to promote harmony between human and nature.

Hu Juntao is a technical officer of the International Union for Conservation of Nature China. Zhang Yan is head of the International Union for Conservation of Nature China. The authors contributed this article to China Watch, a think tank powered by China Daily. The views do not necessarily reflect those of China Daily.

Contact the editor at editor@chinawatch.cn.