Poor agricultural practices, deforestation and the overgrazing of livestock are some of the causes of soil nutrient depletion. These activities ultimately lead to soil erosion, waterlogging, salinization and desertification, which is when soil loses 10 percent of its productivity.
There are many factors that contribute to the global issue of soil nutrient depletion, but one of the biggest is the use of substandard farming processes. Through the application of toxic pesticides and herbicides, pathogenic microorganisms act like a plague, polluting the soil and inhibiting plant growth. Growing crops on steep inclines also significantly degrades soil quality.
Irrigation may cause waterlogging, which is the oversaturation of soil. Waterlogging removes soil nutrients and harms plant roots through denitrification. Another effect of farming is salinization, or the buildup of salts within soil. Soil nutrient depletion has a direct effect on human health, as studies show a diminishing nutritional value from fruits and vegetables over the years.
Plants and vegetation provide a protection mechanism against erosion for the soil surrounding their roots. When the overgrazing of livestock, land development or farming reduces the amount of forestation, erosion occurs at an accelerated rate. As a result of human activity, soil erosion occurs at a much faster pace than soil formation.