Environmental Land Use Conflicts in a Macroscale River Basin: A Preliminary Study Based on the Ruggedness Number

Abstract

Inadequate land use planning is one of the main driving forces leading to the occurrence of erosion and environmental degradation. The negative impacts of poor planning influence soil physical quality and fertility, agricultural productivity, water quality and availability, biodiversity and other ecosystem services. In some areas, actual land use is not consistent with potential use. When this occurs, the area is termed as being in environmental land use conflict. Many studies have demonstrated the efficiency of the ruggedness number (RN) method for determining land use potential in watersheds. The RN method is simple and can be carried out using geographic information systems (GIS). However, the absence of potential land use or agricultural land suitability assessments is recurrent in territorial management plans or integrated water resources plans (IWRP), especially for macroscale river basins. Therefore, the aim of this preliminary study is to identify possible environmental land use conflicts at the Rio Grande Basin (BHRG), Brazil, using the Ruggedness Number. The results indicate high agricultural use potential and the predominance of appropriate or acceptable soil use at the BHRG. However, class 1, 2 and 3 environmental conflicts were identified in some Rio Grande sub-basins, suggesting greater environmental degradation risks. The findings clearly indicate that more exhaustive studies on environmental quality (soil capability, water, biodiversity) are required at the BHRG, especially in environmental land use conflict areas. We emphasize that this is an important preliminary study which may be carried out in any other macroscale hydrographic basin.