The impacts of urbanization on mangroves

Abstract

Mangroves are trees and shrubs that grow in coastal intertidal zones of tropical and subtropical regions. Mangroves cover only 0.1% of land surface but provide valuable ecosystem services that are beneficial to environment and humanity. However, mangrove forests have decreased at a worrying rate over the past decades, under various pressures from both natural and anthropogenic forces. Particularly, urbanization has been widely recognized as an important factor for the dramatic mangrove loss due to the conversion from mangroves to urban land or infrastructures. In previous studies, urbanization was directly represented by spatial expansion of urban land, without considering other perspectives, such as population, economic and social developments that are caused by urbanization. There was also a lack of consideration of the impacts of distal factors driven by urbanization. The interaction and relationship between mangroves and urbanization is highly complex and challenging to be fully understood to balance the environmental and urbanization considerations. To this end, this study aims to 1) identify the temporal and spatial pattern of mangrove distribution and urbanization during the past few decades in China; 2) understand the interaction between urbanization-driven drivers and mangrove ecosystem; and 3) qualify the urbanization-induced impacts on mangroves. Preliminary results indicated that China’s urbanization has complicated relationships and impacts with mangrove forests in China during different periods, and the government’s conservation policy demonstrated significant impacts on the relationship. Outside nature reserves, the impact of urbanization on mangrove forests gradually weakened during the whole study period.