Global mapping reveals more intensively exploited inland than coastal wetlands

Abstract

Losses of coastal wetlands have been observed worldwide, but the extent to which inland wetlands have been exploited by humans is currently unknown on a global scale. Here, we map the distribution of land reclamation over global inland and coastal wetlands using high-resolution satellite observations. Results show that the total area of reclaimed wetlands was 132,886 km2 globally, with about 2/3 contributed from inland wetlands. From 1984 to 2020, the net gain of reclaimed inland wetlands (26,385 km2) was 1.6 times that of coastal wetlands (16,371 km2), due primarily to reduced coastal exploitation in the last decade. We identified significant contributions of wetland reclamation to fishery production, and further revealed greater reclamation rates within than outside protected areas. Our study highlights that the more intensively reclaimed inland wetlands should be highly prioritized, and our global synthesis provides a critical benchmark for assessing potential consequences of wetland exploitation and for future restoration efforts.