Ecuador, Nambija, mercury, Portovelo-Zaruma, arsenic, water, sediment, contamination, Hydrogeology, artisanal gold mining, Ponce Enríquez, Environment, Atmospheric Protection/Air Quality Control/Air Pollution, Aquatic life
Seawater quality, Urban pollution, Uncontrolled discharges, Bay of Cadiz, Sediment quality, Industrial pollution, Industry, Water Pollutants - analysis, Environmental Monitoring, Ecosystem, Water - chemistry, Geologic Sediments - chemistry, Cities, Cluster Analysis, Spain