Hotspots of land use/land cover change around Bolgoda wetland, Sri Lanka

Abstract

Wetlands are among the most productive ecosystems in the world. Urban wetlands are increasingly affected by population growth and developmental activities. A buffer region of 60 m from the Bolgoda lake boundary was gazetted as an Environmental Protection Area (EPA) by the Central Environmental Authority in 2009 as it is the largest freshwater wetland in Sri Lanka. This study attempts to quantify the land use changes during the period of 2001 to 2019 using GIS and to identify the ‘hot spots’ where a significant change in land use occurred. Land use/land cover (LULC) changed in the Bolgoda wetland area disproportionately. The greatest proportion of loss of natural area was observed in dense vegetation, where a 63.35 % decrease was apparent from 2000 to 2019. In contrast, the residential and commercial areas increased and in 2019 the change reached 49.62 % and 68.57 %, respectively. Hotspots were identified at Grama Niladhari divisions that belong to Kesbewa and Bandaragama DS divisions with the largest change in LULC. Thus, the results of the investigation provide vital information for the conservation and sustainable use of wetland resources in a rapidly expanding urban landscape.