土地沙漠化英文介绍 Desertification

Desertification is a type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as climate change and human activities. Desertification is a significant global ecological and environmental problem.

Let’s begin with the areas affected by the desertification

Drylands occupy approximately 40–41% of Earth’s land area and are home to more than 2 billion people.It has been estimated that some 10–20% of drylands are already degraded, the total area affected by desertification being between 6 and 12 million square kilometres, and that a billion people are under threat from further desertification. The Sahara is currently expanding south at a rate of up to 48 kilometers per year.

But how is the desertification coming into being? Here are some Causes.

Desertification is caused by two main categories of factors: natural factors and, more importantly, human activities.The natural factors causing desertification include the following:

1. The climate has a major influence through rainfall, solar radiation and wind, which affect the rates of physical and mechanical erosion as well as chemical and biological degradation of soil.

2.The relief of a land affects the rate of soil erosion by water.

3.The textile, structure, and chemical and biological status of soil are factors determining the soil properties in dry sub-humid zones.

Human activities play a crucial role in desertification. The reasons behind these activities are the increasing demand for food due to the rapid population growth, and inappropriate agricultural practices. The following are some of the human activities that cause desertification:

1.Uncontrolled use of fire for hunting or for agricultural clearing.

2.Over-exploitation of woody resources, particularly for fuelwood.

3.Over-grazing of selective vegetation

4.Over-harvesting which results in abandoned fields

5.Agricultural practices that destroy the soil structure.

6.Inappropriate irrigation of soil, leading to waterlogging and abandoned fields eventually.

Based on the above factors, we can see that the soil becomes unsuitable for vegetation growth and is turned eventually into a desert.

Here are some environmental impacts of desertification

1. The loss of farmlands. Farmlands are important natural resources. Humans rely on them for food. Desertification results in the loss of farmlands, and significantly threatens the living standard and well-being of people inhabiting the areas concerned. This also leads to social problems such as environmental refugees .

2. This breakdown of the environment.Desertification also has serious impact on the natural environment. It breaks down the fragile balance and it represents the start of a process that destroys the natural and stable ecosystem.

3.Another problem is that the results of desertification in turn speed up the natural

你可能喜欢

  • 环境保护PPT
  • 全球环境
  • 分类词汇
  • 英汉翻译教程张培基
  • 新目标英语九年级上期末测试题
  • 雅思作文素材
  • 黑河流域
  • AM-OLED

土地沙漠化英文介绍 Desertification相关文档

最新文档

返回顶部