GDEST 2008 Conference Sessions
Theme 2 - Analysis of Regional Challenges
Assessment of Environmental Vulnerability of Maputo Bay Using Remote Sensing Data and GIS
Alfredo Pontavida, Direcção Nacional de Geologia, Mozambique
The undertaken study was conducted to respond the marine resource management and conservation. As we know the bay comprise the extensive marine environment ranging from pen plan, islands, coral reefs, mangal this is habitat and feeding sources for mollusks, crustaceous and fishes.
Maputo bay is about 40 km long and 30 km wide covering 1200 square km. Within the bay we have Portuguese and Inhaca Islands. In the bay we also have the major port which supports big sheep’s. The principal constraint for coastal management is related to rise of tidal wave due to global warming, construction of tourism infrastructural along the cost which rapidly cause erosion, reduce vegetation cover along the cost and consequently degradation of environment.
The aim of present study is to establish the sensibility index of pollution within the bay in order to support the decision makers in case of spread of oil. NOAA standard was used in this case in order to characterize the environmental sensibility according to geomorphology, permeability, wave and slope. The study was conducted based on two set of Landsat TM7 image from different period (1991 and 2004) acquired from CENACARTA (Centro Nacional de Cartografia e Teledetacção), topographic map, geological map and landuse map from DNG (Direcção Nacional de Geologia) and DINATEF (Direcção Nacional de Terras e Florestas). Tree software (MapInfo, Ilwis & ArcGIS) were used to digitize, process and integrate various data set from different sources. Classified image was produced from Landsat TM bands. In situ visit was undertaken in order to confirm spectral analyses of different class and validate the data process. Map with sensibility index was created and areas prone to environmental degradation were appointed.
As result of this investigation the following was the conclusion regarding to pollution: Costa do Sol area, west part of Inhaca Island, Catembe and Xefina Island are sensitive areas due to expose of mangroves vegetation to marine wave.