Soil and water distribution in China

administration management

China has jurisdiction over 23 provinces, 5 autonomous regions, 4 municipalities and 2 special administrative regions.

Water and soil resources

China has a land area of 9.6 million square kilometers, accounting for115 of the world's total land area.

The total water resources in China are 2.8 trillion cubic meters, of which the river runoff is 2.7 trillion cubic meters. The per capita water resource is only 2220 cubic meters, which is the world average 1/4.

Land use

China's cultivated land area is 94.97 million hectares, but the per capita cultivated land area is only 0.08 hectares, which is the world average 1/3.

The forest area of China is133.7 million hectares.

China's grassland covers an area of 400 million hectares, stretching over 3,000 kilometers from northeast to southwest.

climate

China has a continental monsoon climate, and the rainfall distribution is extremely uneven, from1500mm in the southeast coast to less than 50mm in the northwest inland area.

The complicated and changeable climate in China makes the temperature in China change greatly. The average maximum temperature in September is 28.5℃, and the average minimum temperature is 15.0℃.

History and culture

China has a long history of more than 5000 years. China traditional culture has two origins, one is Confucianism represented by Confucius, and the other is Taoism represented by Laozi.

The most famous cultural achievements of China people are silk, ceramics, architecture, gardening, stone carving and ancient books. .

As the crystallization of China people's hard work and wisdom, many ancient projects, such as the Great Wall, Dujiangyan Water Diversion Project and the underground passage in Xinjiang, have become part of the national cultural heritage.

The Chinese nation consists of the Han nationality and 55 ethnic minorities with different customs and cultures. The Han nationality is mainly distributed in the northeast of China, the Yellow River basin, the Yangtze River basin and the Pearl River basin. The other 55 relatively small ethnic minorities are scattered and have their own unique culture.

agriculture

The main grain crops in China are rice, wheat, corn, soybean and potato crops, in which the output of rice, wheat and soybean accounts for 2/5, 1/5 and 1/4 of the total grain output respectively.

Cash crops include cotton, peanuts, rape, sesame, sugar cane, tea, tobacco, sericulture and fruit.

China has more than 300 million hectares of grassland and more than 400 kinds of livestock, including pigs, cows, sheep, horses, donkeys, mules, camels, chickens, ducks, geese and rabbits.

⊙ 1999 The national output of grain, cotton and oil crops was 508.39 million tons, 3.83 million tons and 260 1000 tons, respectively, increasing by 66.7%, 76.7% and 400% compared with 1978; The meat output is 59,665,438+100000 tons, which is 7 times of 1.978; The output of aquatic products is 4 1.22 million tons, 8.8 times that of 1.978.

⊙ 1999 The industrial output value of villages and towns in China reached $305 billion, and the export value reached $88 billion. At present, there are 20 million township enterprises in China with1250,000 employees. Township enterprises have set foot in many industries such as industry, agriculture, transportation, construction, commerce, catering and so on.

★ Soil erosion in China is not a local environmental problem, but a global environmental problem, which in a sense has become the number one environmental problem in China.

The latest remote sensing data show that the national soil erosion area is 3.67 million km2, accounting for 38.2% of the national land area (if the freeze-thaw erosion area 1.25 million km2 is added, the national soil erosion area accounts for 5 1.2% of the total land area). The types of erosion are hydraulic erosion, wind erosion and freeze-thaw erosion. Among them, the hydraulic erosion area is 6.5438+0.79 million km2, accounting for 48.7% of the loss area, mainly distributed in mountainous and hilly areas. Most of the south is this form of loss; The amount of wind erosion is 6.5438 0.88 million km2, which is mainly distributed in the three northern areas north of the Great Wall, the sand-blown areas in the Yellow River Plain and coastal areas. Desert and Gobi in wind erosion area are extremely difficult to control, only 3 1 000 km2, which is relatively suitable for control.

Diversity of soil erosion disasters in China

1 weakened the ecological barrier of agricultural production.

The ecological environment has played a protective role in agricultural production. A good ecological environment has created favorable conditions for stable and high-yield agriculture. The trend of ecological environment deterioration in China has not been fundamentally curbed. The annual soil erosion area in China is 654.38+100000 km2, the desertification area is expanding at a speed of 2460km2, the forest coverage rate is reduced by half, about 654.38+03%, and the forest quality is declining. Plantations and secondary forests have replaced primary forests. Cultivated land is rapidly decreasing at a rate of more than 60,000 hm2 per year; Biodiversity has been seriously damaged and so on. All these are enough to show that China's ecological environment has entered a fragile section, agricultural production has lost its ecological barrier, droughts and floods have occurred frequently, and the reliability of natural guarantee for high and stable agricultural production has declined.

Sediments in rivers and lakes

Although soil erosion mainly occurs in mountainous and hilly areas, it brings a lot of sediment to the middle and lower reaches, and rivers and lakes are silted by sediment, which greatly reduces the flood discharge capacity of riverbeds and the flood storage capacity of lakes. Taking the Yangtze River as an example, the average sediment discharge of Yichang Station for many years reached 530 million tons. The sloping farmland in the upper reaches of Yunguichuan100000 hm2 is the main source of sediment, and about 60% of the sediment comes from sloping farmland. Secondly, capital construction, such as mining, road construction, resettlement and urban construction. According to the analysis of the sediment deposition in the 235.6km riverbed from Chenglingji to Hankou in the Yangtze River by the Yangtze River Water Resources Commission in recent 20 years, the results show that the sediment deposition in the past 20 years is 200 million tons, and the average height of the riverbed is 0.43m m. ..

3 urban flood control pressure increased

Most of the 660 cities in China are built by water, along the river, along the river and along the coast. Due to sediment deposition in the river bed, the ability of river diversion and flood discharge is reduced, which is bound to bring great flood control pressure to cities along the river. The dangers and disasters caused by the flood peak with the same flow are much greater than in the past. Taking the Yangtze River as an example, the maximum peak discharge of Hankou Station 1998 is 7 1600m3/s, and 1954 is 76 100 m3/s, which is 45000 smaller than 1998. As the saying goes, "the mountain is one inch lower and the river is one foot higher", which is the truth. The resulting dangers and disasters are also more serious. A city is the center of politics, economy, culture and information. According to relevant data, more than 70% of China's gross national product comes from cities, especially economically developed areas. Therefore, once the city suffers from floods, the losses are self-evident. For example, in June 1996, Shenzhen was hit by heavy rain, and the direct economic loss of Buji Town alone reached more than 500 million yuan.

4 aggravated the difficulty of poverty alleviation.

At present, there are still more than 40 million poor people in China, more than 90% of whom live in mountainous and semi-mountainous areas with serious soil erosion, especially in Yunnan, Guizhou, Sichuan, Ningxia, Shaanxi and other provinces (regions). The Party and the government have always attached great importance to poverty alleviation, and solemnly promised to the whole world to eliminate poverty in China by the end of this century. Since the reform and opening up 20 years ago, the poverty-stricken population in China has decreased from 250 million to 42 million now, which is a miracle in the world. Despite this, tens of millions of people living in mountainous areas with serious soil erosion and poor land are still difficult to get rid of poverty, and poverty alleviation has entered a critical stage. One of the important reasons is that soil erosion is serious, the water and soil resources on which people depend for survival are lost, and poverty alleviation has lost its foundation.

Difficulties in soil erosion control in China

China is a big country and a poor country engaged in soil and water conservation. On the one hand, a large area of soil erosion needs to be controlled, on the other hand, the government's "food finance" can't afford so much money to control it. The contradiction between the two is very prominent, which determines the difficulty of soil erosion control in China.

Soil and water conservation is a public welfare undertaking, and many countries in the world rely on government funds to do it. Obviously, China's financial resources are difficult to pay for this huge expenditure.

1 The treatment area is large and the task is arduous.

The existing soil erosion area in China is 3.67 million km2, and there are more than 2 million km2 that really need to be controlled, except for some areas that cannot be controlled (such as Gobi Desert).

According to the national ecological construction plan, in the past 50 years since liberation, the cumulative area of soil erosion control in China has reached 670,000 km2, with an average annual rate of 1.37 million km2. At this rate, it will take 146 years to control the existing loss area. Even if calculated according to the planned annual treatment rate of 50,000 km2, it will take more than 40 years to treat once.

2. The phenomenon of management and destruction has not been fundamentally reversed.

According to the analysis of recent remote sensing data, since the liberation of 50 years, the area of soil erosion in China has increased by 65,438 000 km2 annually, slightly lower than the control area. It can be seen that the phenomenon of destruction while managing has not been fundamentally reversed. I remember that in the early 1980s, Dr. Pei Lisha, a member of the Royal Society, visited Jiangxi Province and said, "Don't destroy it". But in a country with a large population and a small population, how difficult it is to stop the destruction!

After the reform and opening up, the new causes of soil erosion have also changed, from rural energy shortage (cutting down mountains) to large-scale capital construction and urbanization. For example, in the Pearl River Delta, Shandong coastal areas and other places, the new soil erosion caused by urbanization is more serious. Shenzhen is a typical city. 1995 The report of CCTV's focus talk show "Beware of Urban Soil Erosion" on July 20th reflects a new aspect of soil erosion in the process of urbanization. The fundamental way to solve these problems lies in the construction of legal system.

3. Lack of understanding of the significance of soil and water conservation and ecological environment construction.

The harm of soil erosion has been reflected in all aspects of China's national economy, but as people say, soil erosion is a chronic disease, so that our understanding of it becomes normal. In particular, it is even more difficult for the government to invest in governance, and chronic diseases will be delayed.

Due to the lack of understanding of the importance of soil and water conservation, local governments still have such and such situations when implementing many policies that are beneficial to soil and water conservation, especially the water administrative departments, and some policies cannot be implemented. Therefore, in order to do a good job in soil and water conservation in China, we must first solve the problem of understanding, especially the understanding of the importance of soil and water conservation by government leaders at all levels, overcome the idea of quick success and instant benefit, and establish the strategic idea of building soil and water conservation ecological environment projects and realizing sustainable development.

4 investment is seriously insufficient

Soil and water conservation adheres to the principles of local investment, people's input and labor, and appropriate state support. But the point is that the country is too small. From a national perspective, the places listed in the national key governance used to subsidize 6.5438+0.5 million yuan per square kilometer every year, but recently it has been increased to 30,000 yuan, which can only be used for the consumption of agricultural tools, and even the subsidy for seedlings is not enough. Even so, few places are included in the national or river basin institutions for key governance.