Ecosystem health assessment and comparison of natural and constructed wetlands in the arid zone of northwest China

Abstract

Wetlands in the arid zone of northwest China have ecological values such as climate regulation, water conservation, and biodiversity maintenance. However, in the context of global warming and economic development, the degree of natural and human interference in the wetlands has been increasing, and wetland health problems are becoming increasingly severe. The current comparative research on the ecosystem health evaluation of natural and constructed wetlands and their sustainable development in the arid zone of northwest China is not perfect, so we selected the natural (Dunhuang Xihu Wetland) and constructed wetlands (Suzhou District Wetland) as research objects. The ecosystem health evaluation system has been developed from 5 levels of the drive, pressure, state, impact, and response (DPSIR). The ecological health status and impact factors were evaluated for the two wetlands using socioeconomic data combined with remote sensing technology from 2000 to 2019. The results showed that 1) the ecological health of natural and constructed wetlands was in a medium healthy state, and the ecological health values of the wetlands showed a trend of decreasing and then increasing from 2000 to 2019, with 2005 as the turning point. The ecological health status of natural wetlands (0.46) was better than that of constructed wetlands (0.42). 2) The main reasons for the degradation of constructed wetlands (-3.20%) were the urban population expansion and blind agricultural reclamation of wetlands, while the degradation of natural wetlands (-6.45%) was dominated by extreme climatic conditions and overuse of water resources. These results provide case support and a theoretical basis for the conservation management and sustainable development of wetland ecosystems in the arid zone.

Keywords

• Ecosystem health
• DPSIR
• Natural wetlands
• Constructed wetlands
• Arid zone