Evolutions of Distribution and Driving Factors of Coastal Wetland in Bohai Bay, China.
As one of the most vulnerable and economic ecosystems, coastal wetland has high productivity and biodiversity with intensive human activities. The changes of land use led to the loss of 25 ~ 50% of coastal wetland only in the 20th century. Researches on coastal wetland changes, influencing factors and ecological environment effects have attracted widely attention. Remote sensing (RS) is an important tools to monitor the changes of coastal wetland in multi-scale and long time series. Based on RS data, the researches on the characteristics, influencing factors and ecological environment impacts of coastal wetland changes can guide the management, protection and ecological restoration of coastal wetland.
A research team from the Institute of Applied Ecology, Chinese Academy of Sciences recently obtained the annual distribution of Suaeda salsa (S. salsa) using RS data in past 30 years in Bohai Bay, China. And the influencing factors of S. salsa changes were analyzed. Furthermore, taking Liao River Delta estuary wetland as an example, the changes of land use before and after the utilization of wetland and the driving factors of ecological environment impacts were analyzed.
They found that the area of S. salsa lost about 92.63%. Among them, 54.34% of S. salsa has been transformed into other land use types by human activities, while 45.66% of S. salsa has been degraded into bare land by natural factors. Precipitation, temperature, altitude and distance from coastline were the natural influencing factors of S. salsa distribution. Meanwhile, the wetland area of Liao River Delta decreased by 669.64 km2. Ecological environment impacts included three parts: the value of ecological services has lost US $178 million, the area of suitable habitat for water birds decreased by 1449.49 km2, Cd had the greatest risk by potential ecological risk assessment of heavy metals. The wetlands loss, the distribution of Cd and Cr, rivers and oil wells drove the change of ecological environment effects in Liao River Delta.
The study titled “Evolutions of 30-Year Spatio-Temporal Distribution and Influencing Factors of Suaeda salsa in Bohai Bay, China” and “Ecological and Environmental Effects of Estuarine Wetland Loss Using Keyhole and Landsat Data in Liao River Delta, China” published in Remote Sensing, was supported by the National Natural Science Foundation of China.
