Introduction
Farming came in with the evolution of the human being on the planet Earth (Schlesinger et al., 1990). Human need food for a living and their growth, so they use the land to grow crops on it and to get the food from it. The degradation of the land in the dry sub-humid, semi-arid, and arid regions because of the human activities and also due to the climatic variations results in the desertification of the earth. Almost one-third of the total area of the land is composed of the deserts and semi-deserts (De Pinto et al., 2017). Land degradation is a slow process in which the quality of the land become worse slowly, resulting in the declination of the productivity and then results in impacting the lives of the persons who are associated with it for food or other domestic purposes. Degradation of land surface leads to the reduction in the land productivity.
Due to the process of desertification, about 30% of the land is being converted into the desert in China (Guan et al., 2017). About 39.7% of the area of the world land is being under the drylands and is being vulnerable to desertification. Arid land covers about 26% area, whereas dry sub-humid lands cover almost 21% and semi-arid land covers 38% of the total area of the dryland. Desertification can impact a significant effect on the human being due to the shortage of productive land and food by this process.
Discussion
In the recent few years, there is a lot of addition to the land that has been classified as dessert. Land which was covered with plants and vegetation in the recent years has now become dry and barren. This is the conversion of the fertile and habitable land of different organisms into the land of uninhabitable deserts. This occurrence of desertification is mainly due to the reduction in the vegetation. This process can be done either by human activities or by natural actions causing drought. Land can suffer a lot of changes due to this change in the lacking of plants. Plants mostly provide shade to the soil from the sunlight, but once these plants are removed there is a straight path for the sunshine to dry the soil more quickly. Moreover, the plant’s root help in the supporting the land to stay firm. But once these plantation removed, then the soil will be more vulnerable to the erosion by winds. Due to this erosion, the top layer of the soil that is rich in nutrients is removed out resulting in the reduction of the fertility of the soil. Ultimately, the land will dry soon, and lack of vegetation will make it a desert.
The process of desertification can also be caused due to the human activities. For the provision of water to the agriculture, human mostly changes the route of the river from its natural path, due to which that logical path become available to the process of desertification. Because the vegetation in this area which gradually dies due to the stoppage of the water and will result in becoming a desert. Desertification can also be caused due to the poor techniques of the irrigation in an area. Too much usage of water by farmers can result in the overall reduction in the water for that area, which will ultimately lead towards the loss of vegetation and then desertification.
Nowadays, there is an increase in the number of the farm animals, which results in overgrazing (Reynolds et al., 2007). Livestock is damaging the vegetation by grazing it. As the number of animals is increased a lot in the recent years, it ultimately results in more grazing of the plantation. Overgrazing is happening either because the farmers are keeping the livestock in an area for an extended period by which this livestock are eating the grass for the long time which results in the reduction of plantation or when the farmers keep more number of the animals in a small place. As these animals eat the plant down to the roots due to which the growth of the plant becomes short, resulting in the unmaintainable increase of the roots which lead towards the stoppage of the plant growth altogether. Due to this, these more extensive areas soil is exposed to different elements with no vegetation. Landscape changes due to this loss of vegetation which leads towards the destruction of the land’s productivity and can be very catastrophic for the biodiversity of the ecosystem.
Deforestation is also a factor that is contributing a lot to the desertification process. Deforestation is the cutting or removing of the trees form a wooded area. As the human population is increasing in the past years, due to which there is a need for more space on land for the building and residing purposes (Park et al., 2018). Forests are being cut down for making room for the houses to reside or for making room for farmland. Whereas, some desertification can also be caused due to the wildfires, which results in the burning down of many trees. Reduction in the forest land of the world is increasing at higher rates due to which Earth is suffering from the desertification (Zanchetta et al., 2016).
A process of desertification has some catastrophic effects at the global level including the migration of people and dust storms. Majority of the people are being moved into the urban areas from ruler areas due to the significant effect of the desertification in the agriculture of the ruler areas. Due to various studies, it is estimated that about 50 to 700 million people can be subjected to migrate to this desertification. Desertification is being indicated as the primary factor for the migration of the Mexican into the United States, where almost 700,000 people being emigrated from the Mexican drylands annually (Symeonakis, 2016). Different studies from the Africa, Niger and Burkina Faso shows that the desertification results in the migration of the human and it also makes a worse condition for the living of both who leave their places and those who remain behind.
Desertification is also the primary cause of the origination of the dust storms from the drylands where there is no vegetation. Dust storms result in the deposition of a lot amount of dust in areas which occurs in the affecting many town and cities. Major dust storms can cause health problems along with the burying of the houses, equipment, and even the trees. Dust storm also results in the death of the farm animals and may lead to dust pneumonia for persons. A dust storm in China for about three weeks results in the closing of the roads, railways, and hospitals (Wang et al., 2017). Dust originating from the dust storms may contain different pollutants and many toxins, like sulfur, pesticides, and salt which may cause severe damage to human health. Moreover, desertification is the primary reason behind the global food crises (Berdugo, 2017). As the vegetation is decreasing at a higher rate than it may eventually result in the threat of the global food security.
Desertification also has many negative impacts on the regional levels. Most of the areas are facing very different climate and weather patterns due to the change in climate by the deforestation. Due to this change of the environment, the terrestrial biomass also adjusts due to the difference in the range and species composition. Due to which there is a massive impact on both the ecosystem functions and physical process like the water cycle, resulting in the change of the zones of the food production and crops. All these climates changes result in the incidences of the drought and heavy rainfall in different regions of the world. Increase in the number of droughts and floods have a widespread and stronger impact in destroying of the land. About 2 billion people are being affected by the desertification because of their lives mainly dependant on the agriculture (Geist, 2017).
Due to continual change of the climate and by the new global temperature there is a reduction in the rainfall in the most of the dryland areas of the worlds, which may come to some considerable impacts for desertification and land cover. In the beginning few decades, there will be a reduction of almost 10-30% of the overall river run-off and in the availability of the water in the dry regions of the world. About 2.4 billion people may be subject to live in the areas where the water scarcity is intense by 2025, and approximately 200 million people may permanently migrate due to the desertification by 2050.
To avoid the desertification, there should be a sustainable agriculture procedure in which there is reasonable livestock such as the limited number of the animal grazing should be used. Moreover, there should be a rotation of the grazing lands due to which one can avoid the overgrazing of the plantation. Furthermore, the reestablishment of species of the plant can help in the curbing of the effects and may lead to a reduction in the desertification in that area. As the forest acts as a source of the absorption of the carbon dioxide due to the process of photosynthesis from the atmosphere. But with the deforestation, the released carbon dioxide will result in the formation of the greenhouse gases, which will ultimately lead towards the global warming and climatic change. Due to the greenhouse gases, the earth will eventually heat up, causing the warming of the earth surface. Due to the warming of the Earth’s surface, the fertile land will eventually convert into the desert due to the evaporation of the water from the ground.
Dehydration then causes the drying of the land, and no water will leave for these plants to absorb, so they will eventually be died out and results in the process of desertification. Scientists should need to develop some technique for the reduction of the desertification of the productive land. Renewable energy should be used instead of using fossil fuels and woods as a source of fuel so that there will be a reduction in the creation of the greenhouse gases.
Conclusion
Recent studies have shown us about the causes of global desertification and its effects on the human and our ecosystem. There are a lot of the factors that contribute towards the process of the desertification including the overgrazing, deforestation, but the primary factor for the cause of the global desertification is overpopulation (Bastin et al., 2017). Desertification results in the massive migration of the human from ruler to urban areas which leads towards the overcrowding in the cities. Climate also changes due to the desertification, which ultimately results in the formation of the floods and many massive storms of dust which can be catastrophic for human beings.
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