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Soil Degradation

Full text: In this video, the causes and consequenses of soil degradation are explained. The word soil degradation contains the word degrade. This is used when a decline in performance is explained. So, it has gotten worse. This also applies to soil degradation. If the soil degrades, it is actually less useful, reducing the yields of food, timber or fresh water. This may be because people have poorly maintained the land. Suppose crops grow in an area. People remove the vegetation, like trees and plants. For example, people need the wood and there is deforestation. People can also graze cattle and the cattle eat all the vegetation. This is called overgrazing. Vegetation disappears in the event of deforestation or overgrazing. Normally roots hold the soil, but because there are no roots left, the soil is no longer held. During a heavy rain shower, the soil can then be washed away. This is called soil erosion. What remains is a hard, stony bottom layer. New plants can't get in with their roots and can therefore barely or not grow at all. Also, with a new rain shower, the water cannot enter the soil, so that it washes over the surface. Because there is no water available in the soil, vegetation can grow even more difficult. The soil thus loses the capacity to grow plants and trees and to retain water, causing soil degradation. In areas with a lot of precipitation and a lot of relief, the soil can wash away much more easily. More water is available and because the bottom is steep, it will wash away more easily. Another form of soil degradation is salinization. This means that there is a concentration of salt in the soil. That's because people irrigate the land. They use a lot of water in warm and dry areas on agricultural lands. But even drinking water contains a little bit of salt. If the water evaporates on land due to the heat, the salt remains, because it does not evaporate! The cause of salinization isn’t because the water washes away, but because it evaporates! In this way, salt accumulates, decreasing plant growth. As a result, the yield of agriculture is decreasing and thus there is soil degradation. One solution may be to improve the efficiency of irrigation channels, so that less water is needed and therefore less salt ends up on the land. Soil degradation in a fairly dry area can lead to desertification. The soil can no longer hold water in an already dry area, so nothing can grow. Then a desert is created. This is successfully countered in some areas by digging into the soil, loosening the soil and planting new trees. Soil degradation can be worsened by climate change. Dry areas are generally becoming drier due to climate change, making these areas more vulnerable to soil degradation. In short: soil degradation makes the soil less usable for agriculture, for example.