A scene of the Futian Mangrove National Nature Reserve in this file photo. A high-level international forum on mangrove protection opened yesterday and will last through Friday. Mangrove is Shenzhen’s city tree. Shenzhen has 213.62 hectares of mangrove trees and aims to build itself into an international wetland city by 2035, with 50% of its wetlands under protection, as per a draft plan of the city government.Liu Xudong