According to the Sole Regulating Environmental, and Sustainable Development Decree (Decree 1076 of May 26, 2015), this type of pollution “cannot be determined because there is not an exact discharge point to the body of water or soil.”
In other words, there is an interaction between rain, contact with the ground, and a trawling effect, which carries materials, nutrients, agri-chemicals, and fertilizers that can end up in water currents or water sources such as rivers, lakes, groundwater, and glaciers, among others, resulting in this type of pollution.
According to the research project of Universidad Nacional de Colombia (UNAL) Engineering-Water Resources M.Sc. and Environmental Engineer Camilo Bernal, the water resources of diffuse pollution, and mismanagement of agricultural products in crops near rivers are causing a surge in nutrients to bodies of water, besides limiting the growth of species, increasing foul odors producing impacts to human health, and possibly sanitarian difficulties to the community.
“Currently, the absence of methodologies to obtain information of diffuse pollution could cause a weakness in the care of nutrient generators that generate eutrophication processes, i.e. algae and aquatic plants that restrict oxygen exchange between water, and the environment,” said Bernal.
In Colombia, water currents are researched and supervised by agencies that carry out environmental monitoring, such as the Ministry of the Environment, and Sustainable Development (MADS, for its Spanish acronym), the Hydrology, Meteorology, and Environmental Studies Institute (IDEAM, for its Spanish acronym), and different authorities or Environmental Corporations.
According to the National Policy for the Comprehensive Management of Water Resources, water follow-up protocols look to improve water quality and promote the reduction of pollution to water sources with a firm goal for the year 2022. However, the water quality follow-up methodologies rarely consider diffuse pollution.
This led the researcher to inquire which is the best form to carry out diffuse pollution monitoring that impacts the water sources of the country, knowing there is no known method or guide to take samples in this case. So, Bernal studied the Siecha River –which lies between the municipalities of Guasca and Guatavita (Province of Cundinamarca), due to the agricultural activities that have taken place in recent years, as shown by a 2016 MADS report that shows the increase in cattle ranching and agricultural activities in crops like potato, fruits, flowers, chickpeas, and other vegetables, that have produced changes in the topsoil.
Bernal began his research in a land plot with three representative crops of the region: strawberry, peach, and potato. He recorded all sorts of precipitation (any form of water particles that fall under gravitational pull from clouds of the region), size and stages, and input for every crop and the features of the soil, besides the weather season.
He also carried out a topographic survey of every crop and according to the typical characteristics of the soil, he dug ditches that led the water to a storage point to take samples. Using a pluviometer, he recorded the water fall and cross-referenced this data with measurements from entities such as IDEAM, and the Corporación Autónoma de Cundinamarca (CAR).
At the water storage point, he measured the water volume and took samples to take to the lab for physical-chemical analysis and analyze the collected data.
The results showed there is a high load of nutrient agri-chemicals (nitrogen and phosphorous) in potato crops: “This is because this crop has less planting-harvest time than any of the other crops and the land must be fertilized with different kinds and types, and amounts of chemicals. Also, when the first harvest is over, they quickly continue with the next, avoiding the land to recover its natural properties.”
Bernal also analyzed the bacteria linked the fecal matter of organisms (total and fecal coliform bacteria,) obtained from rainwater samples and discovered that “different crops had these bacteria and although their origin can come from water taken from the Siecha River, there is also the possibility of it coming directly from nearby livestock activities, limiting the use of water sources downstream and speaks about the care that should be taken when consuming products without the appropriate cleanliness”.
The researcher calls on the environmental and agricultural agencies to implement strategies and methodologies to help identify these effects and control them opportunely.
As an important contribution, this data requires a deeper analysis of the features of the ground, the pollutant mobility potential of rainwater, and its trawling effect, besides including the conditions that contribute to the transportation of pollutants to groundwater.
“The field information is vital for research in the country. However, it should be constant and assessed in different conditions and geography areas of the Colombian territory, with the intention of strengthening the indirect methods that could be useful for decision-making and provide policies, an objective for the whole of the country,” said the researcher.
Consejo Editorial: Fredy Chaparro Sanabria Director Unimedios, Nelly Mendivelso Rodríguez Oficina de Prensa, Liseth Sayago Cortes Oficina de Realización Audiovisual, Carlos Raigoso Camelo, Oficina de Producción Radiofónica, Ramiro Chacón Martinez Oficina de Proyectos Estratégicos.
Editora: Liliana Matos
Diseño y desarrollo del sitio web: Martha Lucía Chaves Muñoz Oficina de Medios Digitales
Contacto: Oficina de Prensa-Unimedios, teléfono 3165000 extensiones 18432-18108, Correo electrónico: firstname.lastname@example.org
Redes sociales: Twitter: @PrensaUNAL, Facebook: Prensa UNAL