China's wetlands loss to urban expansion

TLDR

Wetlands provide essential ecosystem services, yet worldwide wetland loss has surged due to rapid urbanization, and China’s expanding cities threaten to further erode these habitats. This study aims to quantify the spatial extent of wetland loss driven by urbanization in China. Using the China National Land Cover Database, the authors analyzed wetland loss patterns from 1990 to 2010. From 1990 to 2010, China lost 2,883 km² of wetlands—2,394 km² in eastern regions—with the loss rate accelerating 2.8‑fold between 2000–2010, disproportionately affecting reservoirs/ponds and marshes, driven mainly by built‑up area expansion and concentrated in four hotspots (Beijing–Tianjin, Yangtze River Delta, Jianghan Plain, Pearl River Delta).

Abstract

Abstract Humans benefit from multiple ecosystem services of wetlands, but massive wetland loss has occurred worldwide due to rapid urbanization. To assess the problem, it is necessary to quantify the spatial extent of urbanization‐induced wetland loss. Here, we investigated the amount and pattern of wetland loss in China due to urbanization from 1990 to 2010, based on the China National Land Cover Database (ChinaCover). Our results show that, during these 20 years, China lost 2,883 km 2 of wetlands to urban expansion, of which about 2,394 km 2 took place in the eastern regions (Northeast China, North China, Southeast China, and South China). The rate of urbanization‐induced wetland loss was 2.8 times higher between 2000 and 2010 (213 km 2 year −1 ) than between 1990 and 2000 (75 km 2 yr −1 ). Of all wetland categories, reservoirs/ponds and marshes suffered the most severe losses. Most of the wetland loss was due to the expansion of urban built‐up areas rather than industrial or transportation lands. Four hotspots of urbanization‐induced wetland loss in China were identified: the Beijing–Tianjin metropolitan region, the Yangtze River Delta, the Jianghan Plain, and the Pearl River Delta. Urbanization and industrialization continue to unfold in China for the next few decades, and the rapid expansion of small‐ and middle‐sized cities and urban traffic networks is expected to encroach on more wetlands. Although great efforts have been made towards wetland conservation in recent years, China must prevent more wetlands from being wiped out by urbanization if the country is to ahieve its sustainable development goals.