Analyze the impact of deforestation in mountain areas on downstream areas and cities? 40

Hehe, this seems to be a college entrance examination question, I have encountered it in the college entrance examination before.

1. Soil erosion, which leads to the blockage of the river and leads to poor shipping.

2. Pollute water quality, affect urban living, water and industrial water.

3. The decline and decrease of water quality will affect the development of agriculture.

4. The destruction of forests can lead to the desertification of the land and the formation of sand storms.

5 may lead to the formation of floods.

The deforestation of mountain forests will reduce the environmental protection function of mountain forests in conserving water and maintaining water and soil, resulting in a series of problems such as serious soil erosion in mountainous areas, increased sediment content in rivers, and aggravation of downstream flood disasters.

Soil erosion, increased sediment content in rivers, increased flooding downstream, rising groundwater levels downstream, and salinization (salinization) of soils.

Geological disasters: collapses, landslides, debris flows, soil erosion, land desertification;

Meteorological disasters: sandstorms, etc.

Geological hazards, a technical term in geology, refer to geological processes (phenomena) formed under the action of natural or man-made factors that cause damage and loss to human life, property and the environment. Such as collapse, landslide, debris flow, ground fissure, soil erosion, land desertification and swamping, soil salinization, as well as volcanoes, geothermal hazards, etc.

Meteorological disasters are one of the natural disasters. It mainly includes Asian tropical storms, typhoons in coastal urban areas of China, droughts, high temperatures, flash floods, thunderstorms in southern China, and sandstorms in northern China. Hurricanes, tornadoes, hail, and heavy rain (snow) are common in North America.

China is one of the few countries in the world where natural disasters occur very frequently and there are many types of disasters, causing very serious losses.

For plants and animals with weak mobility, the population density of the population is generally investigated by sampling method The most direct factors determining the population density are the birth rate and mortality rate, in the figure o a, the population density of the species increases, and the number increases, indicating that the birth rate of the population is greater than the mortality rate in this time period; In section b c, the community transitioned from the perennial herbaceous stage to the shrub stage, the shrubs replaced the perennial herbaceous plants, and the perennial herbaceous plants gradually decreased to a relatively stable level, indicating that the community could tolerate the low light environment caused by the shrubs and maintain a relatively stable population in this environment. After point C, if the climatic conditions are suitable, tall trees can get enough light to replace the dominant shrub and become the dominant plant type in the area

The area has been treated to increase the vegetation cover, and at the same time, the increased vegetation can fix more carbon (CO2) through photosynthesis, increasing the output of agricultural and forestry products, and achieving the simultaneous development of ecological and economic benefits

Therefore, the answer is: the birth rate is greater than the death rate of trees and carbon (CO2).

According to the legend and schematic diagram, the areas with serious forest destruction in the Yangtze River basin are the Hengduan Mountains and the Yunnan-Guizhou Plateau

Therefore, c

a In the development and utilization of mountainous areas, natural disasters such as collapses, landslides and debris flows are highly susceptible, so it is wrong;

b. China's complex and diverse topography provides favorable conditions for the development of agriculture, forestry, animal husbandry and other operations according to local conditions.

c The mountainous area is vast and the ground is rugged, which leads to inconvenient transportation, so it is correct;

d The mountainous area is vast and the ground is rugged, which is not conducive to the development of the shipping industry

China's topography is characterized by complexity and diversity, and the mountainous area is vast The mountainous areas are prone to natural disasters such as collapses, landslides, and debris flows When developing mountainous areas, we can use the mountain rapids to generate electricity, use the mountainous landscape to develop tourism, and appropriately exploit the mineral resources in mountainous areas, but we must pay special attention to the construction of the ecological environment and prevent and avoid the occurrence of mountain disasters

Therefore, c

The mountainous area has great advantages in the development of tourism, mining and agricultural diversification It is not conducive to the development of large-scale planting The mountainous area is relatively rugged, prone to soil erosion, inconvenient transportation, and difficult infrastructure construction Therefore, option d is in line with the topic; Options a, c, and b are not in line with the topic

Therefore, d