遥感与地理信息系统学报

抽象的

Exploring the Impact of Urban Growth on Surface Waterbody Area Loss in Khulna City using GIS Techniques

MD Marufuzzaman*, Mst Mahbuba Khanam and Md Kamrul Hasan

Surface water body ensures environmental sustainability, natural beauty and temperature balance in the urban area. Nowadays the surface water bodies is being filled up to meet the rapid urbanization. The aim of this study is to find out the location and the amount of filled up surface water body area in Khulna City Corporation (KCC) during the last twenty years (1998-2018). Satellite image analysis by geographic Information System (GIS) provides much more accurate result about the land cover change of any area. In this regard supervised image classification method of GIS technology has been applied in this study on Landsat satellite image to identify the location and amount of filled up surface water body area. According to the result, there is a significant land cover changed happen in the last twenty years in Khulna city area and a considerable amount of surface water body area has been replaced by the built-up urban space. The result shows that in 1998, total surface water body and built-up area was 7.4502 and 20.214 square kilometers, but in 2018 the built-up area spread 25.6815 square kilometers which significantly reduce surface water body area to 5.9598 square kilometers. The result also shows that conversion from surface water body to built-up urban area at the period of 1998 to 2008 and 2008 to 2018 rise from 0.7038 to 1.2132 square kilometers. Surface water body area not only conserves biodiversity but also retain an excessive amount of water during rainy seasons. Without proper management of surface water body area, Khulna city may face frequent urban flood during rainy seasons, which may increase the sufferings of urban peoples.