Fallati Luca, Savini Alessandra, Sterlacchini Simone, Galli Paolo
MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Maldives.
Department of Earth and Environmental Sciences, University of Milan - Bicocca, Piazza della Scienza, 2-20126, Milan, Italy.
Environ Monit Assess. 2017 Aug;189(8):417. doi: 10.1007/s10661-017-6120-2. Epub 2017 Jul 26.
The Maldives islands in recent decades have experienced dramatic land-use change. Uninhabited islands were turned into new resort islands; evergreen tropical forests were cut, to be replaced by fields and new built-up areas. All these changes happened without a proper monitoring and urban planning strategy from the Maldivian government due to the lack of national land-use and land-cover (LULC) data. This study aimed to realize the first land-use map of the entire Maldives archipelago and to detect land-use and land-cover change (LULCC) using high-resolution satellite images and socioeconomic data. Due to the peculiar geographic and environmental features of the archipelago, the land-use map was obtained by visual interpretation and manual digitization of land-use patches. The images used, dated 2011, were obtained from Digital Globe's WorldView 1 and WorldView 2 satellites. Nine land-use classes and 18 subclasses were identified and mapped. During a field survey, ground control points were collected to test the geographic and thematic accuracy of the land-use map. The final product's overall accuracy was 85%. Once the accuracy of the map had been checked, LULCC maps were created using images from the early 2000s derived from Google Earth historical imagery. Post-classification comparison of the classified maps showed that growth of built-up and agricultural areas resulted in decreases in forest land and shrubland. The LULCC maps also revealed an increase in land reclamation inside lagoons near inhabited islands, resulting in environmental impacts on fragile reef habitat. The LULC map of the Republic of the Maldives produced in this study can be used by government authorities to make sustainable land-use planning decisions and to provide better management of land use and land cover.
近几十年来,马尔代夫群岛经历了剧烈的土地利用变化。无人居住的岛屿变成了新的度假岛屿;常绿热带森林被砍伐,取而代之的是农田和新建区域。由于缺乏国家土地利用和土地覆盖(LULC)数据,马尔代夫政府没有制定适当的监测和城市规划战略,所有这些变化就发生了。本研究旨在绘制整个马尔代夫群岛的首张土地利用图,并利用高分辨率卫星图像和社会经济数据检测土地利用和土地覆盖变化(LULCC)。由于该群岛独特的地理和环境特征,土地利用图是通过对土地利用斑块进行目视解译和手工数字化获得的。所使用的图像拍摄于2011年,来自数字地球公司的WorldView 1和WorldView 2卫星。识别并绘制了9种土地利用类别和18个子类别。在实地调查中,收集了地面控制点,以检验土地利用图的地理和专题准确性。最终成果的总体准确率为85%。在检查了地图的准确性之后,利用21世纪初来自谷歌地球历史影像的图像创建了LULCC地图。分类地图的分类后比较显示,建成区和农业区的增长导致林地和灌木地减少。LULCC地图还显示,有人居住岛屿附近泻湖内的土地开垦有所增加,对脆弱的珊瑚礁栖息地产生了环境影响。本研究制作的马尔代夫共和国LULC地图可供政府当局用于做出可持续的土地利用规划决策,并更好地管理土地利用和土地覆盖。