Drylands cover about 54 million km 2, which amounts to 40% of the global land area, and are especially common in Asia and Africa, where they account for 58. The first problem is that the harsh environment and the large population of impoverished rural residents make the income from traditional farming highly vulnerable to natural disasters such as drought and to fluctuations of market prices ,. Where conditions permit, can avoid degradation by improving their agricultural practices and enhancing pastoral mobility in a way. Desertification Today in many countries lands are becoming into deserts,and due to the conditions in the world soon we will not be able to take it backThere are two main causes of desertification,one is human activities and the other is climatic variations. Although the policy that restricts grazing has been implemented for almost a decade, livestock remain a significant cause of desertification. Globally around 2 billion acres of land have become deserts in the past 50 years. Famine, poverty and political instability While desertification certainly leads to these problems, they can also be a cause of desertification.
This natural process has caused misery among those most directly caught in its path, turning productive land into dryland. We used the mean of these two values to represent the monthly mean, and then selected the maximum value from monthly data to represent the year. This suggests that interdisciplinary research will be required to fully understand the sociological factors and their interaction with natural factors so that appropriate policy measures can be developed to focus on those factors and interactions. In addition, desertification has been a major driver behind the historical movement of large populations of humans — which obviously plays into the collapse of civilizations. For example, planting trees which often have low water-use efficiency in arid regions often requires supplemental irrigation, which exacerbates the stress on an already limited water resource , increases evapotranspiration, and can even exacerbate soil erosion if the trees outcompete herbaceous vegetation for water, leading to decreased vegetation cover at the soil surface ,. Despite greatly improved knowledge of weather systems, the use of meteorological satellites, and advanced computer simulation of climate, farmers today are more exposed to climate extremes than ever.
It is the process of the loss of soil productivity and the thinning out, gradually, of the vegetative cover resulting from human activities and climatic variations. More people also increases the demand for food which can result in over cultivation and over grazing. In some cases this has caused and conflicts between herders and farmers who claimed access to the same land. Afforestation and planting of soil binding grasses can check soil erosion, floods and water logging. Done right almost any desert can be restored to good land again, with minimum effort, except for halting logging companies as they usually do not see trees as long term assets but as timber commodity. Similarly harmful is cultivation of already deteriorated lands.
These drylands are therefore highly susceptible to climatic variations and increase in base human pressure. . These regions have suffered from climate change, unfavorable hydrologic conditions, changes in vegetation composition, loss of soil services, and desertification; the combination of these effects has generated many adverse consequences, including sandstorms that threaten ecosystem services and human life. This process turns usable desert land into unusable land due to poor land management. Causes of Desertification Desertification results in continued degradation of land and of fragile ecosystems.
This mixture varied with time, place, and culture, since the harsh conditions forced people to be flexible in their use of the land. Link to the video about the Loess plateau: and shorter: If we look at the Shara southern border, it greens up in the desert time after time and every time animals are allowed up to eat the grass, but also the tree shoots, effecitively ensuring that the desert remains. The notions of desertification and land degradation have been criticized commonly on various grounds Thomas, 1997; Eswaran et al. Interactions between climate and desertification. However, the afforestation area was not significantly correlated with desertification dynamics, which suggests that afforestation did not contribute to desertification control in the long term.
For example, trees can be used to preventsoil erosion and reduce polluted runoff into nearby bodies of water. Thus, these two terms do not uniquely identify the driver of degradation, nor the state of the degraded system. This method should be identified in future research to improve the ability of this research to support restoration planning. Point 2 Mass migration hits the nail on the head. To include, the conditions in some African countries are not good for the production of food thanks to the unfertile soils in certain locations. This means that it will be difficult to fully understand the driving forces responsible for desertification in China without understanding the unique context of each region, and that monolithic policies will work less well than adopting policies that address the most significant driving factors for each region. It could be concluded that the driving mechanisms of the desertification processes in Zhalute banner are mainly the policy of cropland expansion and the rising populations of humans and their livestock, which has affected the land use pattern in the past decades.
The current rate of desertification is around 15 million acres per year, the worst being in sub-saharan Africa. This change spoilt the delicate natural balance, which had evolved over thousands of years. Livestock number, farmland area, road construction, and mean annual temperature were significantly positively related to the change in the area of desertification, accounting for 30. They can help us push the limits of our current understanding of desertification. Desertification is the process by which fertile land is transformed into desert as it becomes progressively drier and unable to support any plant growth for food production.
Very severe desertification:In this type of desertification, composition of active naked great sand dunes occurs and formation of many grooves and valleys and the salinization of the soil which leads to soil degradation. This will allow future researchers to better control this error term and more precisely estimate the impacts of individual factors. Because of overgrazing, plants are eaten by mammals before they grow and multiply,then lands become arid. And what remains left is a lifeless pile of dust instead of a life-giving medium. Likewise, biodiversity may increase in the degraded state Maestre et al. This essay will define and describe both of these views. Key 1 is to stop herding animals on high ground, else no trees can root there.