Answer:
The ten activities that can result in the contamination of the rivers of a watershed are:
- Mining.
- Metallurgical Industry.
- Oil extraction.
- Hospitals and other medical services.
- Agriculture.
- Livestock.
- Tourism.
- Tanneries.
- Final disposal of solid waste.
- Production of electrical energy.
Explanation:
Mining, depending on the type of mineral that is extracted, can incorporate extremely dangerous substances such as cyanide or mercury into adjacent rivers, which are sometimes used for gold extraction.
The metallurgical industry does not usually dispose of its solid waste ineffectively, however, there is a big problem with its discharges, which are usually loaded with different metal ions that are disposed of in water sources and increase their load.
Oil extraction has demonstrated its great potential for contamination of water sources thanks to the fracking method, by which the rock is broken for the extraction of gas and oil, however, in turn, water sources, both underground and surface, are contaminated, to the point that water is flammable due to its high content of these products in it.
Hospitals and other medical services tend to have discharges with a high organic load, which if they were disposed of in rivers could greatly contaminate them, in addition to other by-products of this activity such as pathological residues could become a big problem if they were not disposed of a correct way.
Agriculture regularly uses fertilizers that can be carried to water sources due to runoff, causing problems such as eutrophication.
In the event that intensive but extensive livestock farming is not carried out, where the livestock travels in large areas and even approaches water sources to drink water, there is a high probability that the water will be contaminated by their excrement, being disposed of within the same water source or transported by runoff.
Not all tourists have good habits, there are tourists who take walks or other activities in open areas without any care, leaving solid waste near the rivers of the basin or even contaminated after performing their physiological needs.
Tanneries use elements such as chromium in their processes, which has a high probability of reaching adjacent rivers and greatly polluting them.
Solid waste constitutes a serious pressure problem for soil and water, whether its origin is domestic or industrial, poor disposal of it can cause its final destination to be a river, polluting it and reducing the diluted oxygen there which in turn destroys the aquatic fauna of the place.
The production of conventional electrical energy, regardless of the method used, has serious impacts on water sources: Thermoelectric plants make use of water at room temperature which returns to high temperatures (despite using cooling ponds), plants Hydroelectric plants pause the river's route causing an oxygen deficit at the base of the river and therefore no aquatic life, finally, with nuclear plants, there is the possibility that the waste from such activity is not properly contained and ends up contaminating sources underground and surface areas of the sector.
