Risk assessment of wetland degradation in the Xiong’an New Area based on AHP-EWM-ICT method

Abstract

Increased groundwater exploitation can cause severe groundwater depletion and may trigger geological hazards such as wetland degradation. The Xiong’an New Area is an important deployment of the national strategy to promote the coordinated development of the Beijing-Tianjin-Hebei region. The protection of wetlands will play an important ecological role in the socio-economic development of the Xiong’an New Area. This paper proposes an improved catastrophe theory (ICT) combined it with the analytic hierarchy process (AHP) and the entropy weight method (EWM), labelled AHP-EWM-ICT method. This method was applied to evaluate the evolutionary trend of the wetland degradation risk in Xiong’an New Area from 2000 to 2020. Results showed that, first, the wetlands degradation risk in the Xiong’an New Area was fluctuating upward, with an increase of 80.17% in 2020 compared to 2000. The risk level increased from ‘Very low’ in 2000 to ‘Medium’ in 2020, and most years at ‘Medium’ level during 21 years. Second, Rongcheng County, which has the higher intensity of groundwater extraction as well as the higher per capita GDP compared with Xiong County and Anxin County, contributed most to wetland degradation. The stress degree values progressed from northwest to southeast. Third, due to the implementation of ecological recharge, the degradation risk of Baiyangdian wetland has shown a trend of first increasing and then decreasing. Fourth, the risk of wetland degradation in Xiong’an New Area may be more severe than in other wetlands in northern China. In addition to implementing ecological replenishment projects, the government should also pay more attention to the functional restoration of wetlands and the reduction of risk sources in areas surrounding wetlands.