Wetland shift monitoring using remote sensing and GIS techniques: landscape dynamics and its implications on Isimangaliso Wetland Park, South Africa

摘要

Various forms of competition for water and amplified agricultural practices, as well as urban development in South Africa, have modified and destroyed natural wetlands and its biodiversity benefits. To conserve and protect wetlands resources, it is important to file and monitor wetlands and their accompanied land features. Spatial science such as remote sensing has been used with various advantages for assessing wetlands dynamic especially for large areas. Four satellite images for 1987, 1997, 2007 (Landsat 5 Thematic Mapper) and 2017 (Landsat 8 Operational Land Imager) were used in this study for mapping wetland dynamics in the study area. The result revealed that the natural landscapes in the area have experienced changes in the last three decades. Dense vegetation, sparse vegetation and water body have increased with about 14% (5976.495 km(2)), 23% (10,349.631km(2)) and 1% (324.621) respectively between 1987 and 2017. While wetland features (marshland and quag) in the same period experienced drastic decrease with an area coverage of about 16,651.07 km(2) (38%). This study revealed that the shift in the vegetation and water body extents have contributed detrimentally to the drastic declined in the Isimangaliso Wetland Park in recent years. Consequently, this development might have negative effects on the wetland ecosystem and biodiversity and the grave state of the wetland in the study area requires an urgent need for protection of the dregs wetland benefits.