Detecting and understanding drivers of natural and ecoenvironmental vulnerability due to hydro geophysical parameters, ecosystem and land use change through multispectral satellite data sets in Apodi estuarine, Northeast Brazil

The Apodi estuarine located in the north coast of Rio Grande do Norte State; it is a typical and key valley region with apparent upland ecosystem vulnerability and sensitivity. In order to analyze natural and ecoenvironmental vulnerability, remote sensing (RS) and geographical information system (GIS) technologies are adopted and an environmental numerical model is developed using DIP techniques. The objective of this study was to improve our understanding of natural and ecoenvironmental vulnerability; it´s causes basically show the intensity, its distribution and humanenvironment effect on the ecosystem in the Apodi estuarine, so that a strategy of sustainable land use could be established. The model contains some basic factors like geology, geomorphology, soil, vegetation and land use/cover. According to the numerical results, the vulnerability is classified into six levels, unrated/potential, very low, low, medium, high, and very high levels, by means of the cluster principle. Vulnerability maps have the aim to show the intensity, and its distribution in the study area, of the susceptibility of the environment. The results show that the natural vulnerability in the study area was at medium and high level, and ecoenvironmental vulnerability is quite more sensitive in maximum part of the study area. However, the ecosystem quality had become worse over the thirty years in some regions. In the study area, population growth, encroachment, industrialization, vegetation degradation, and governmental policies for ecoenvironmental protection were found to be the major factors that caused the environmental changes over the thirty years.