Numerous studies have pointed out the environmental effects derived from organic wastes from aquaculture production (Burridge, et al., 2010; Wang, et al., 2012, Chou et al 2002). Quiñones et al (2019), find that the organic wastes increase in load of organic matter on the seafloor. Negative effects on the ecosystem have been detected through the degradation of the sediment around the farms (Karakassis, et al., 2000; Kalantzi & Karakassis, 2006; Tovar, et al., 2000. Eutrophication of Patagonia channels and fjords due to salmon culture in Chile has been recognized as an environmental risk of salmon production (Buschmann and Pizarro, 2002; Soto y Noranbuena 2004; Buschmann et al, 2006; Quiñones et al, 2019).
In our study, we reviewed the environmental reports of salmon farming companies in Chile, which are legally required to monitor pollution caused by organic waste. We analyzed data from 2013 to 2019 for farms located in the Salmon Concession Group (SCG) number two in the region of "Los Lagos" in the south of Chile. We focused on those that assessed the impact on biodiversity using ecological indicators such as Dominance (D), Diversity (H), and Evenness (J). To determine the spatial and temporal distribution of pollution we used different geostatistical interpolation methods such as Ordinary Kriging and Inverse Distance Weighted (IDW). Our results (Figure 1) indicate that from 2013 to 2019, most seafloor in SCG number two experienced medium to high pollution levels, with a significant loss in biodiversity during periods of intense salmon farming. This was particularly evident in 2013, 2016, and 2018, when a larger portion of the study area exhibited severe contamination compared to sectors with moderate or mild pollution.