Both desertification and desertification cause the gradual loss of its vegetation cover of the soil, which triggers conditions of extreme desolation leaving barren lands.
The difference between the two concepts is that the desertification It is caused by natural causes, while the desertification It is due to the actions of the human being.
What actions are behind both? Initially, the worst thing is that they are not usually independent, but generally the natural processes that lead to the aridity of an area are often accentuated by bad agricultural practices such as cultivating in areas of excessive slope, plowing in favor of it instead of adapt to the contours of the land, do not land (build terraces on the slopes), etc.
Once a specific area begins to degrade, it is usually added the existence of torrential rains that drag a large amount of loose land towards more depressed and less steep areas. The soils suffer erosion, while the rivers loaded with sediments become dangerous to suffer obstruction of its channel in addition to filling the reservoirs or depressed areas. As a consequence, the risk of flooding will increase in the following rainfall, when floods occur in river courses.
Natural generation of a desert
A desert is conditioned by:
• Climatic agents: basically the downpours and the wind are the main mobilizers of sediments, when acting on the soils and transporting their materials.
• Nature of the substrate: the vulnerability that presents to the wear by the atmospheric agents is a function of parameters such as its composition, the permeability, disposition, etc…
• Topography or relief of a region: It will be transcendental in the face of erosion that you will experience in the future. The more abrupt, exposed to climatic factors and greater slope present, the faster it will be dismantled or degraded.
• Loss of vegetation: the vegetation cover is a fundamental factor in the conservation of the substrate since it protects it from the inclement weather, while the roots anchor the sediments preventing them from being transported by water in surface runoff, or by winds.
Artificial creation of desert conditions
The causes are all anthropic:
• Deforestation: it can be done both physically (manual start, logging, burning of stubble ...) and chemical (use of herbicides, for example).
• Agriculture with unsustainable techniques: it implies that the soil loses its nutrients and finally after a certain number of crops it will no longer be suitable for agriculture and grazing. That is why in Spain in the past there was the custom of leaving some land "fallow", which meant that this season the plot would not work so that it could recover from the overexploitation to which it was being subjected.
• Overgrazing: the excessive food of herbivores together with the excessive passage of cattle leads to the disappearance of vegetation in that area and the mineral impoverishment of the substrate.
• Mining and quarries: they produce the remobilization of large volumes of earth and rocks, as well as the discharge into the atmosphere of a large amount of suspended dust that, when moved by the wind, exerts greater erosion on the reliefs it affects. The rains deposit these molecules on land, on the plants, preventing them from performing photosynthesis properly.
• Public Works: many involve the breaking of slopes on the slopes of the hills and mountains, cuts on the slopes, formation of gullies ... so that the lands end up sliding in favor of the slope, giving dangerous falls of stones of different sizes towards the roads, collapsing when yielding the ground that sustained them, etc.
• Town planning: it involves the creation of artificial reliefs where there were none before, influencing and altering the wind flows that existed until then in the place. By adding asphalt, concrete and other products, the existing insolation / evaporation conditions change affecting the climate. At the same time it brings with it a greater demand for water and other resources to the area, the underground construction of pipelines, the electrical laying on the surface, the mobilization of vehicles pouring chemical gases into the atmosphere, etc.
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