Environmental Risk Assessment of Mining to Argentine High Andean Wetlands

IZQUIERDO, ANDREA E.; FOGUET, J.; GRAU, H. RICARDO

Berlin

Congreso; Global Land Project Open Science Meeting: Land transformations: between global challenges and local realities; 2014

The assessment of the threats of human activities to natural ecosystems is one of the more important components of an effective conservation planning process. Consequently, understanding the spatial relationship between these risk elements and ecological health within focal conservation sites provides valuable insight into conservation management. We mapped and quantified human impact by mining to High Andean wetlands from Argentine Puna and High Andean ecoregions, a study area of 14.231.505 ha, located above 3500 m elevation in NW Argentina High Andean wetlands (lakes and peatbogs) represent the highest biodiversity and productivity of high elevation Andean ecosystems, and provide essential ecosystems services to local inhabitants. They contribute a significant proportion of primary productivity, maintain vertebrate populations, and regulate hydrological resources, which have high incidence in urban and agricultural areas downstream. While historically the region has been affected by grazing; presently the combination of global markets and domestic policies suggest mining will expand rapidly in the region, with potentially vast impacts on water cycles. We developed a map of wetlands and an Environmental Risk Surface (ERS) to High Andean wetlands by mining. The map of wetlands was based in Maximum likelihood classification of Landsat (30x30 m resolution). The ERS was developed by assigning different intensity values and influence distances to indirect threats (i.e roads) and direct threats considering visual impact and a characterization of each mining project and prospect (i.e. exploited material, type of work, state, production); and summarizing an overall contribution of mining impact in a final risk spatial raster model. Finally, we analyzed the overlay of the wetlands with this ERS, and calculated a risk rating for each wetland. The total surface of wetlands is 113.143 has (0,79% of study area), which 34.560 ha are petbogs (0,23% of study area) and 80.474 has are lakes (0,56% of study area). Only 11.400 ha of petbogs (35% of total area) occurred in area with some level of risk (5267 ha in level 1, 5938 ha in level 2 and 194 in level 3). While, 22498 ha (28% of total area of lakes) of lakes are in areas with some level of risk (7538 ha in level 1, 7901 ha in level 2, and 7058 ha in level 3). These risk assessments vary according to different geographic categories (e.g. elevation, size, shape, temporal variability); that need to be considered as basis of land use planning and environmental impact assessments in the region.