Located in north-east China’s Changbai mountain system, Jilin Hani Wetlands are part of the Longgang volcano group and mainly comprise forested and non-forested peatlands. Boasting the thickest peat layer (9.6 metres) in north-east China, the Site is one of the most important carbon sinks in the biogeographic region and helps maintain the carbon cycle in the Hani river basin. The peat layer developed through the Holocene period with continuous and fast deposition of diverse plant residues; a peat pillar in the Site provides a rare geological archive of the evolution of the Holocene environment. The Site is mainly fed by rainfall and surface water from bedrock fissures at the foot of the mountain. It is in the headstream region of the Hani river, which flows into the Hunjiang river (a primary tributary of the Yalu river) and is also in the Hani river water conservation area, which is the only source of drinking water for the city of Tonghua. The Site provides important habitats for a wealth of biodiversity, and plays a key role in water conservation, flood control, groundwater recharge, and regulation of the regional microclimate and the carbon cycle in north-east Asia.