Read the diagram of the Wuyur River Basin. Answer the next question. Question 1: Bei'an City is located in the upper reaches of the Wuyuer River Basin, and the area of soil erosion accounts for 45% of the total area.
Small question 1: A?
Small question 2: D?
Small question 3: B
< p>Test question analysis:
Small question 1: Test the ability to analyze the causes of ecological problems (water and soil erosion). The conditions for the occurrence of water and soil erosion include: large terrain undulations, concentrated and intense rainfall, loose surface soil, and low vegetation coverage. This question examines the climatic conditions. Bei'an City is in a temperate monsoon climate zone, with concentrated rainfall and frequent heavy rains in summer. It has seasonal frozen soil at high latitudes. During the freezing process of seasonal frozen soil, groundwater water moves up and freezes in the frozen soil. The frozen soil The water content increases and the volume expands. The thawing process is slow. In early spring, the ice, snow and topsoil repeatedly thaw during the day and freeze at night, making the originally loose black soil even looser. The unthawed frozen layer below acts like a water barrier to prevent melting snowwater from seeping down. The snowwater flows down the slope, causing a large number of rills on the slope and eroding the surface soil. Bei'an has the characteristics of "nine droughts in ten years", and the topsoil is dry and cracked. Without crop coverage, strong winds will cause the soil to move, causing the soil to move with the wind, flying dust and even sand and rocks, leading to serious soil and water loss. Intense sunlight and large temperature differences cannot cause soil erosion.
Small question 2: Test the ability to analyze problems. Rarity is characterized by features that are not found in other areas or are atypical. The rarity of the Wuyuer River Nature Reserve is reflected in its geographical advantage. The reserve is located in the upper reaches of the Wuyuer River in the Songnen Plain, in the inland of Northeast Asia. It is a breeding ground for many coastal wintering and inland breeding birds. It is also a migratory transition zone and breeding ground for wintering birds in Australia and Southeast Asia and breeding birds in the northern near-polar regions; Wuyur River Nature Reserve has excellent ecological conditions, and many rare species are distributed here, such as wild soybeans and other wild plants; There are storks and other rare and endangered animals, and there are 39 species of first- and second-level national key protected animals in the reserve; the surrounding areas of Wuyur River Nature Reserve were developed relatively late and are rarely damaged. There are basically no residential areas and buildings in the planned core area. At the production point, the ecosystem within it has been evolving and developing according to its own rules. It is the natural background of the wetland ecosystem in the Songnen Plain area of China and is a very well-preserved wetland ecosystem.
Small question 3: Examine the function of water diversion channels based on materials. Due to the impact of climate change (global warming) and human activities (human interception of wetland water) in nature reserves, wetland water storage capacity is generally declining, leading to severe degradation of wetland ecosystems. Water is the life of wetlands. Without water, there would be no wetlands. Among the three main characteristics of wetlands (hydrology, soil, vegetation), hydrology is the most important factor in the formation and succession of wetland ecosystems. Hydrological changes have a great impact on the wetland ecological environment. The main purpose of the central Yinnen (River) Canal is It is to replenish the ecological water of the wetland and maintain the ecological water supply of the wetland.