Challenge Project

This project utilized tools like ArcGIS, QGIS, GeoJSON , Javascript and Leaflet to create three maps displaying different geographic phenomena related to illegal mining activity in Madre de Dios, Peru.

Illegal Gold Mining: Peru's "New Cocaine"

In Peru, illegal gold mining is a big business. Illegal mining, which began at a small scale artisinal level, has now grown into a multi-billion dollar industry. The illegal gold trade in Peru produces about three billion dollars of untaxed annual revenue, more than the cocaine trade. Illegal gold mining has several negative implications on the environment such as deforestation, soil erosion and ecosytem poisoning via mercury. Mercury infiltrates the ecosystem by leaching through soils and settling into the river bed. Mercury bio-accumulates in plants; these plants are then eaten by fish which travel through the region. These fish are often caught and eaten by locals.

The above map identifies two illegal mining sites, as well as nearby population centers. To learn more about each mining site, click on the shovel icon and a pop-up will appear with some information. Information regarding the name and population of each population center is also available in pop-up format.

The above map shows stream order of the Malinowski and related rivers. Stream order was calculated using flow direction of the base DEM and the delineated stream raster. According to this preliminary model, streams tend to flow from west to east. The justification for creating this model operates under the assumption that fish in the region tend to travel downstream more often than upstream. The migration patterns of fish are important to understand the potential spread of methylmercury contamimation within the ecosystem. ArcGIS was used to create this map.

The above map shows points of critical flow throughout the lower Malinowski and related rivers. Points of critical flow are defined as areas in the stream with a downward slope of 25 degrees of higher. Critcal flow points were mapped in order to determine points in the river were fish may have difficulty swimming upstream. These points were identified by calulcauting the slope of stream raster pixels. More must be known about migration patterns of relevant fish to continue with this analysis.ArcGIS was used to create this map.


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