Scientists from the British Geological Survey (BGS, for its acronym in English) and the University of Lancaster, in the United Kingdom, warned about a nitrate "time bomb" that could have serious consequences for the planet.
They calculated that up to 180 million tonnes of nitrate (roughly twice the amount in soils) is accumulating in rocks around the world as a result of the use of chemical fertilizers in the agricultural industry.
These amounts of nitrates could reach rivers and seas, increase the amount of algae, cause fish kills, contaminate drinking water reserves, among other serious consequences for the planet and human health.
In ecology the termeutrophication designates the nutrient enrichment of an ecosystem. The most widespread use refers specifically to the more or less massive contribution of inorganic nutrients in an aquatic ecosystem.
Eutrophication generally produces an increase in biomass and an impoverishment of diversity.
The algae explosion that accompanies the first phase of eutrophication causes a cloudiness that prevents light from penetrating to the bottom of the ecosystem. As a consequence, in the background, photosynthesis, which produces free oxygen, becomes impossible, while the oxygen-consuming metabolic activity (aerobic respiration) of decomposers increases, which begin to receive the excess organic matter produced near the surface. In this way, oxygen is soon depleted in the background by aerobic activity and the environment soon becomes anoxic. The radical alteration of the environment that these changes entail makes the existence of most of the species that previously formed the ecosystem unfeasible.
Where they are
These "pumps" are distributed throughout the world, especially in the rocks of North America, China and Europe, where these nitrogen fertilizers have been applied extensively and for decades.
Matthew Ascott, hydrologist at the BGS, assures that “the water and the pollutant travel very slowly through the rocks under our feet, this and a history of intensive agriculture, mean that a large amount of nitrate contamination has accumulated with the weather".
"With large investments to reduce water pollution through changes in agriculture, it is vital that we understand that pollution already exists in the environment."
According to the specialist, when this contamination is released, it will affect water quality for decades, even in places where controls on the use of fertilizers have been established.
Conventional farmers consider fertilizers to be vital to guarantee agricultural productivity, but despite this the European Union is trying to stop the application ofnitrates.
With information from: