Traditional siltation of Pearl River

First, the connotation and essence of harmonious coexistence between man and nature

Harmony means that all the elements and parts in the system are in proportion and well coordinated. An ecosystem, especially in global, regional or local areas, is a complex system of cattle community and its environment (including water, atmosphere, soil, rocks, etc.). ) is interdependent, interdependent, relatively stable and self-organized, and water is the most active and important controlling factor. While nourishing everything, water affects the evolution and changes of the whole nature with its own laws of abundance and dryness and dynamic characteristics. All life elements in the ecosystem are born of water and exist according to it, which is very sensitive to the quantitative and qualitative changes of water. To build water conservancy projects and eliminate floods, human society thrives and develops in the dependence and struggle with water. Dealing with the relationship between man and nature in water control has become an important topic for the sustainable survival and development of mankind.

The so-called harmony between man and nature in water control refers to people-oriented, balance and coordination between man and nature. Under the framework of the whole basin ecosystem, we should properly handle the relationship between human activities and water conservancy and water disasters, rationally seek advantages and avoid disadvantages, correctly treat natural disasters such as floods and droughts, and reduce man-made disasters such as water pollution. At the same time, minimize the interference of human activities on the water cycle and reduce human encroachment on water. Handle the relationship between human water intake and other water use in nature, control the development and utilization of water resources in a state that can maintain the basic functions of water bodies and the sustainable utilization of water resources, so that water can benefit the whole nature while benefiting human beings.

Adhering to the concept of harmonious coexistence between man and nature in water control reflects the change of value orientation. From "people-oriented" and the value concept of human controlling and ruling nature, it has changed into a people-oriented, comprehensive, coordinated and sustainable development concept, emphasizing the harmonious development between man and nature and human progress. Adhering to the harmonious coexistence between man and nature in water control reflects the change of thinking mode. From an isolated, single-goal way of thinking to a systematic, comprehensive and dialectical way of thinking, from the previous goal of economic growth to the coordination of economic growth and ecosystem protection, comprehensively considering various advantages and disadvantages, while transforming nature to meet human needs, restraining human behavior and taking into account the harmony and stability of nature. The concept of harmony between man and nature involves all aspects of water control, from ideas, countermeasures and measures to planning, design and management, it needs constant exploration, practice and innovation.

Second, the harmony between man and nature is the only way for economic and social development to a certain extent and stage, and it is the inevitable choice for human beings after summing up their experiences and lessons.

In the long history before the industrial revolution, the level of productivity was relatively low, human activities had little impact on nature, and man and nature maintained a relatively harmonious state. Philosophy emphasizes the connection, similarity and unity between "heaven" and "man", "nature" and "man-made". Zhuangzi believes that "heaven and earth coexist with me, and everything is one with me", and heaven and man are one; Confucius advocated the theory of "destiny", regarded "destiny" as the master of all things, and asked people to "respect destiny" and "fear destiny"; Laozi advocates "natural inaction" and thinks that people are powerless in front of nature and society. This simple view of "harmony between man and nature" has led to the close and harmonious relationship between China's generation and nature. When dealing with the flood, we should "choose hills" to avoid the flood, "move the city to avoid it", "dredge the nine rivers" to divert the flood, and leave enough space on both sides of the river for the water to "rest, swim left and right, and be slow but not urgent" to store and detain the flood, which are all full manifestations of this idea. In the development of water and soil resources, the pre-Qin period emphasized that "the axe can enter the mountain with time, but the tree can't be used" and "those who don't plant trees have no trees", which played a very good role in protecting vegetation and planting trees.

With the passage of time, the rapid increase of population, the accumulation of human experience and knowledge, and the development of science and technology, especially after the industrial revolution, the ability of human beings to transform and influence nature has become stronger and stronger, and the idea that "man can conquer nature" and "man is the master of nature" has become stronger and stronger, and nature has gradually been regarded as an inexhaustible treasure, exploited and utilized unscrupulously, and at the same time regarded as a bottomless garbage bin. In recent decades, China's action of "changing the world" is unprecedented. In order to carry too many people, strive for more space and produce enough food, people occupy the river beach, reclaim land around the lake and destroy forests (grass) to open up wasteland; In order to meet the rapidly increasing demand for water, people have built one water storage and diversion project after another, which can cut off the Yellow River, dry up the Haihe River, drain the underground aquifer and use every drop of water. In order to reduce the production cost, sewage and wastewater are discharged into rivers and lakes without treatment.

More than a hundred years ago, Engels pointed out that human beings can dominate nature by changing it to serve their own purposes, but every step we take must remember that human beings never stand outside nature when ruling nature.

Nowadays, the concept of sustainable development is deeply rooted in people's hearts. Facing all kinds of problems in the field of water resources in China, it is an inevitable choice to change from "transforming and conquering nature" to "harmony between man and nature". Of course, this choice is not a simple repetition and regression of the distant past, but an all-round development and sublimation based on a deeper understanding and grasp of the law of water control and the pursuit and desire for sustainable development.

Three, adhere to the harmony between man and nature, we must adhere to respect the laws of nature, give full play to people's subjective initiative in water conservancy, and take the road of sustainable development of water conservancy.

The sun and the moon keep running, and the rivers keep running, which naturally has its own operating rules; Human beings take water, use water and drain water, and water enters human society. Water control activities need to follow social laws. Only by constantly discovering and understanding the law, following the law and applying the law in the practice of water control can we achieve tangible results.

1. Under the framework of ecosystem protection and restoration in the whole basin, the countermeasures to solve the water resources problem in China should be considered as a whole.

Watershed is the carrier of water resources, and any river, lake and other water bodies are closely related to their watersheds. Healthy rivers and lakes must have a healthy watershed ecosystem as the foundation and support. In the practice of water control, the solution of water resources problems should be considered under the framework of ecosystem protection and restoration in the whole basin.

The protection and restoration of watershed ecosystems include not only aquatic ecosystems such as lakes, rivers and wetlands, but also terrestrial ecosystems such as forests, grasslands and farmland. Mainly refers to the rational development and utilization of water, land, wetlands, vegetation and other natural resources in the basin, limiting or eliminating all kinds of disturbances that cause the degradation of the ecosystem, and realizing the sustainable utilization of water resources and the virtuous cycle of the ecosystem.

Protecting and restoring vegetation and wetlands in the basin will play a certain role in alleviating floods and droughts and reducing soil erosion and water pollution. From the hydrological point of view, forest vegetation and its underlying soil are like sponges, which can absorb a certain amount of rainwater (flood) when rainfall occurs, and then gradually release it, flow into rivers or infiltrate into underground aquifers. If forest vegetation is destroyed, the ability of soil to conserve water will be weakened, and the speed of rainwater flowing into rivers will be accelerated, which will undoubtedly aggravate the degree of flood in flood season and drought and water shortage in non-flood season. In addition, vegetation degradation will aggravate the degree of soil erosion by rain, increase the siltation of rivers and lakes, aggravate the flood disaster, and also adversely affect the development and utilization of water resources. Wetlands have a similar function. They can control floods in rainy season and can be used gradually in dry season. The research shows that every increase of 1% wetland area in the basin will reduce the river flood peak by nearly 4%. At the same time, vegetation, swamps and other forms of wetlands can naturally filter pollutants and excessive nutrients in the water flow, block sediments and improve the anti-pollution ability of water bodies.

In recent years, in vegetation restoration, the ecological environment in many areas has been improved obviously by emphasizing the use of natural laws, making full use of nature's self-repair ability and combining local artificial measures. Practice shows that the vegetation coverage of some degraded land can be greater than 0.6 after 3 to 5 years of enclosure. For large-scale ecological restoration projects such as returning farmland to forests (grasslands), closing hillsides to prohibit grazing and returning grazing to grasslands, although economic benefits can be considered on a large regional scale, local economic and social development and the improvement of people's living standards must be solved in the long run, and a benign development mechanism must be established. By implementing measures such as comprehensive management of small watersheds, warping dams, changing slopes into ladders, small water cellars and rainwater collection cabinets, a certain number of high-standard farmland will be built to solve the problems of farmers' food consumption and development; Irrigation "grazing" by developing artificial grassland

District water conservancy ",to solve the problem of animal husbandry development after grazing suspension and grazing prohibition; By developing small hydropower instead of fuel, solar energy, biogas and firewood forest, the rural energy problem can be solved and large-scale vegetation restoration can continue.

After 1998, the middle and lower reaches of the Yangtze River returned a large area of farmland to water (rivers and lakes) to protect wetlands and waters, which made a good start in solving the problem of water competition for land. However, China is a populous country with precious land resources, so we should make good use of water bodies and wetlands, protect them in the process of utilization and use them in the process of protection. To make good use of water bodies and wetlands, it is necessary to consider the utilization of water and soil resources as a whole. The core is to make good use of water, such as planting aquatic cash crops and aquaculture, developing sightseeing agriculture, industry and wetland cattle-raising tourism, forming flood economy and wetland industry, and finding a new balance between people and water.

In recent years, China has strengthened the construction of water source protection projects, such as groundwater recharge and benefit protection in over-exploited areas, water transfer in cattle system in ecologically fragile areas, and water replenishment in arid wetlands. These beneficial attempts and practices have achieved good results.

2. The flood disaster is inevitable, and the flood loss can be reduced, so the flood management mode of "people and water * * *" should be established.

There are about 6,543.8+100,000 km2 alluvial plains in the lower reaches of rivers in China, which are the products of river flooding and sediment deposition, and are also the areas most threatened by floods in China. Because of fertile land, flat terrain and convenient transportation, the Yangtze River Delta, Pearl River Delta and many other areas have become densely populated and economically developed areas in China. It is impossible and impossible to make major adjustments and changes to the already formed population distribution and productivity distribution in China. The losses and impacts caused by flooding and river diversion are unbearable and tolerable in today's society. Therefore, it is unrealistic to let the river flow freely and return to the natural state, and it is by no means a manifestation of harmony between man and nature.

It is impossible to eradicate the flood. Even if the flood control standard reaches the standard stipulated in the plan, there is still the possibility of exceeding the standard flood, and the flood control standard of rivers in China is still very low. Therefore, we must pay close attention to the construction of flood control safety systems such as soil and water conservation, reservoirs, dikes, flood storage and detention areas, and dispatching systems, so as to raise the flood control safety standards to a level suitable for economic and social development and protect people's lives and property. At the same time, in flood-prone areas, it is necessary to establish lifestyle models, economic models and water and soil resources development and utilization models that are conducive to reducing flood losses. In the struggle against flood, people should learn to enjoy the space with water to reduce the loss of flood. In addition, study the laws and characteristics of floods, reduce siltation by using the scouring and bed-building effects of floods, and control rivers, such as the Yellow River water and sediment regulation experiment; Strengthening the research on the limited water level of reservoir in flood season and improving the utilization degree of rain and flood resources are all explorations of using flood and turning harm into benefit.

3. Drought can't be cured, water shortage can be alleviated, and a reasonable and coordinated water use model can be established.

Drought is the main natural disaster in China, especially in the north. Due to the limitation of renewable water resources and the change of abundance and drought, the problem of ten droughts is inevitable and cannot be completely eradicated. In arid, semi-arid and other fragile areas and semi-humid areas in China, the development and utilization of water resources must fully consider the water demand of the ecosystem in the basin, and consider the water demand of life, production, livestock and environment as a whole to maintain the basic ecosystem balance.

To alleviate the problem of water shortage caused by drought, comprehensive countermeasures must be taken. It is necessary to construct a rational allocation system of water resources from the perspective of harmonious development of people, economy, ecology and environment, a balance system of supply and demand of water resources from the perspective of open source, throttling and protection, and a guarantee system for reducing drought losses from the cooperation of engineering measures and non-engineering measures. China's annual water consumption accounts for about 20% of the country's annual renewable water resources, but there is a great imbalance between river basins, and there is still potential for development and utilization in many places. Proper construction of rainwater harvesting and diversion projects can effectively alleviate the pressure of water supply and demand and regional imbalance. At the same time, this will be an effective way to expand the scale and scope of development and utilization of non-traditional water sources such as floods, sewage, inferior water and seawater. Improving the efficiency and benefit of water resources utilization, establishing a water use model adapted to local water resources conditions and vigorously promoting the construction of a water-saving society are the fundamental measures to alleviate the shortage of water resources. In addition, we should carry out a series of necessary non-engineering measures to prevent drought, and improve the ability of the whole society to resist drought by formulating and implementing drought planning, emergency plan and emergency management, drought monitoring, information research and drought prediction, drought relief and public education.

Water pollution is a problem in the process of human development.

The damage to the water body should also be solved. If floods, droughts and some natural disasters are involved, water pollution is purely a man-made disaster. The serious pollution of water body not only endangers people's life and health, but also causes serious losses to the national economy, and also affects the development and utilization of water resources. Different from developed countries and regions such as the United States, Japan and Europe, China has encountered serious water pollution problems in a low development stage and in a short time. When the United States and Japan began to prevent and control pollution in the late 1960s, the per capita GDP was more than 10 times higher than the current level of China, and China was faced with sustained and rapid economic and social development and

Double pressure to improve environmental quality.

Controlling and controlling water pollution and repairing polluted water bodies require huge manpower, material resources and financial resources, and require long-term and arduous efforts. First of all, in order to control pollution sources and reduce pollutant emissions, it is necessary to clarify responsibilities, strictly enforce the law, change the current practice of "paying sewage charges or exceeding the standard discharge" in exchange for "legal" discharge rights, and put an end to the inaction of administrative organs and pollutant discharge enterprises. The second is to increase the environmental carrying capacity of water bodies. Through scientific and reasonable dredging of rivers and lakes, endogenous pollution can be reduced; Strengthen the scientific operation of reservoir dams, maintain the proper flow of water, achieve the purpose of running water without rot, and increase the self-purification ability of water; Explore the technical feasibility of large-scale remediation of polluted water bodies. The third is to increase the transformation of agricultural production methods. A handful of chemical fertilizer makes crops green, and a bottle of pesticide ensures a bumper harvest of grain and cotton. However, the excessive use of chemical fertilizers and pesticides leads to soil acidification and hardening, soil fertility decline, a large number of beneficial organisms die, resulting in serious water pollution. It is necessary to vigorously raise farmers' awareness of environmental protection and actively promote green agriculture and green farming methods.

5. Dialectically treat the advantages and disadvantages of human water control activities and establish a comprehensive, long-term and dialectical concept.

The starting point of water control activities is undoubtedly to benefit mankind, but comparing different reference systems, different goals and different time, the evaluation of the advantages and disadvantages of human water control activities may draw completely different conclusions. With the gradual improvement of knowledge level, the development of science and technology and the change of pursuing goals, the requirements for water control activities are constantly changing and developing. Now the requirements for water conservancy projects have been raised to be beneficial to both human beings and ecology, and not at the expense of destroying ecology. In recent years, China has carried out the practice of ecological protection and environmental beautification in dike construction, such as avoiding using impervious materials to protect rivers, attaching importance to the connection between banks and respecting the diversity of rivers, and has accumulated some experience. In foreign countries, some radical environmentalists demand that the dam be removed and the river return to nature. This is the other extreme, which is certainly not desirable.

The key to the harmony between man and nature in water control is to follow the laws of nature and treat the relationship between man and the whole basin with respect and caution. As for the water resources problem, from the perspective of the overall sustainable development of the basin,

On the surface, it is to think, explore and solve problems from the harmonious development of complex dynamic system composed of land, water system and biosphere. It should be said that the safety and interests of people's lives and property should be and will be.

It must be protected and satisfied, but in the long run, it protects the whole nature, protects the ecosystem and, in the final analysis, protects human beings.