Abstract: Coastal wetland of China is consisted of lowland, tidal flat and associated biological community. Its total area covers 1/5 of China's wetlands and runs across 39 latitudes in the northern hemisphere. The nature of coastal wetland is characterized by monsoon wave action, tidal dynamics and large river influence. According to their genetic features,coastal wetlands can be divided into three types: reed and grass wetlands of estuary, grass and salt marsh of plain coast, and mangrove swamps located in the sheltered bay head of South China. All of the three types have the zonation features of being divided by superior tidal zone, inter tidal zone and sub tidal zone. Coastal wetlands are precious space resources, but owing to effects from forest denudation, foreign species invasion, coastal erosion, frequent flood disaster and red tides intrusion, the environmental quality of coastal wetland has deteriorated gradually. To deal with the contradiction between wetland's ecological protection and basic living requirement of local residents, a systematic study on environmental nature of regional wetlands is needed, by comparison and summarization of successful and unsuccessful practices, to find out the critical value for best protection of wetland's nature and suitable way of wetland utilization.

Key words: coastal wetland, salt marsh, mangrove swamp