Spatial patterns variation in water quality parameters under the influence of hydrocarbon composites exploitation in a hydrographic unit of the Napo River Basin : Spatial variability of physicochemical water parameters applying raster correlation analysis in the Aguarico River.

Abstract

Aguarico River, a prominent freshwater body stream in the in the Northeastern Ecuador, currently lacks of comprehensive understanding regarding the spatial and temporal variability in water parameters. The primary objectives in this study are characterize concentrations and heterogeneities of water quality parameters under the influence of oil resources exploitation over space and time, identifying which of those physicochemical attributes have most negatively impacted the water quality in the region. In order to achieve this, the dataset employed to perform the predictions and interpolations comes from water samples collected at nine unique sites in 2013 and 2014, along with fourteen additional points in 2015. Sixteen water quality parameters were analyzed using layering tools and interpolation techniques. While most parameters fell within permissible ranges defined by Ecuadorian and international guidelines, Apparent Color (Pt-Co), Sulfur as Hydrogen Sulfide (H2S), Temperature (ºC), and Turbidity (NTU) exceeded allowed thresholds. Upon statistical analysis, the average WQI value for the consecutive three-year timeframe was 59.67 points, ranking “medium” in the category of water quality status. This deterioration in water quality can be attributed to anthropogenic activities, most certainly those related to the oil industry. In fact, oilfields located within Block 56 and Block 57 are distinguished as primary sources of contamination due to their substantial production of formation water, characterized by their moderate to high concentrations of Salts and Barium (Ba) This study highlights the potential risks of pollutant exposure to local settlements along the Aguarico River and its tributaries. Focused on the Napo River Basin, it compares datasets with current regulations, emphasizing the need for regulatory interventions to safeguard human health and environmental sustainability in the region.