Restrospectiva Crítica del Estado Ambiental y Social de la Laguna de Yahuarcocha, periodo 1920 - 2022, cantón Ibarra, provincia de Imbabura.

Abstract

Yahuarcocha constitutes an outstanding tourist destination in the province of Imbabura due to its historical and cultural value. It is located in the Inter-Andean Alley and around it an attractive tourist infrastructure has been developed for tourists since different recreation options are offered; However, poor management of natural resources leads to the degradation of ecosystems, modifying the dynamics of species populations, changes in the ecological structure, loss of species, among others. The water level in the Yahuarcocha lake has gradually decreased since 1917 due to factors such as evaporation and the reduction of the flows that supply it. Studies indicate that, for 43 years, the depth of the lagoon has decreased as a result of the dragging of sediments. In 1966 an aqueduct was built that helped restore water levels; However, the introduction of exotic species and human activity have had a negative impact on the environmental quality of the lagoon. Additionally, the intermittent water regime of the Manzano Huayco, Santo Domingo and Polo Golo streams, among other streams, in addition to the presence of contaminants and the decrease in dissolved oxygen, contribute to the deterioration of the ecosystem. The proliferation of algae such as Planktothrix agardhii represents health risks, which is why, among the researchers' recommendations, the implementation of measures such as limiting the extraction of cattails and regulating the entry of nutrients stands out to address these problems. According to several authors, Yahuarcocha lake is experiencing critical levels of pollution in its environmental environment, excess algae and aquatic vegetation, a low water level and sedimentation problems. Actions such as the construction of the highway without environmental studies have caused damage due to excessive erosion, loss of soil, alteration of bird populations, etc. The pollution caused by the discharge of wastewater, the lack of fish farming knowledge that years ago led to the introduction of fish that could reduce or cause the disappearance of the lagoon's native species, are factors that, over the years, have contributed to the degradation of this wetlandCurrently, according to research carried out by academia, government entities and the scientific community, it is known that there is a high level of eutrophication that continues at an accelerated rate, due to its high productivity, high concentrations of phosphorus, nitrogen and carbon; all this, as a result of an absence of the authorities that control demographic growth, the location of tourist, hotel and agricultural infrastructure. The purpose is to compile and retrospectively analyze the environmental, social and biological factors that have intervened in the loss of environmental quality of the Yahuarcocha lake over time, to contribute to the objective understanding of the environmental problem. , suggesting lines of research and management of the resource; For which, based on updated information available by the Municipio de Ibarra, a hydrographic, land use, physicochemical and biological characterization was presented. The retrospective analysis of the review of 42 publications corresponding to undergraduate and graduate theses, scientific articles and technical reports generated by public institutions allowed us to know the environmental, social and biological factors that contribute to their degradation. In this way, an objective understanding of the environmental problems is facilitated, which ultimately allows us to suggest lines of research and management of the resource. Knowing the measures taken by government institutions provides a more complete perspective on the management of the microbasin and the current state of this significant lake in the province.