Ecosystem Base for Land-Use Planning in the Coastal Plain of Rio Grande do Sul

Abstract

The number of researches related to ecosystem functions and services has increased almost exponentially in the last decades, which indicates the importance that the scientific community has given to the recognition of the maintenance of the ecosystem base in meeting the demands of society. In the terrestrial portion of coastal zones, these demands usually fall on the supply of space for tourism, urban, port, agricultural, aquaculture, forestry, livestock and mining, among others. The increasing conversion of habitats to such uses has been pointed out as the greatest threat to these ecosystems. The first challenge to a sustainable territorial occupation is therefore to understand the ecosystem functions present in a given region, to identify the more or less sensitive areas for the development of different human activities, and to shape them into a process of Economic Ecological Zoning (ZEE, in Portuguese). To do so, a selection of appropriate indicators is needed to summarize the high complexity and connectivity of ecosystems in a simple and understandable model. This study, developed in Lagoa dos Patos Island Barrier, in the middle segment of the coastal plain of Rio Grande do Sul state, presents a methodological proposal for spatial planning in coastal zones, based on the identification and maintenance of ecosystem functions and services. As a result, three classes of use were defined for a region in order to maintain its structural and functional properties, called Environmental Preservation Zones, Conservation Zones and Development Zones. Since the quaternary genesis of this island barrier is associated to the same physical processes that acted in the formation of the coastal plain of Rio Grande do Sul, it is proposed to apply this method in all the extension of this coastal plain, as already done in the municipality of Rio Grande, on margins of the Lagos dos Patos estuary.