What are the hazards associated with the construction of reservoirs?

The possible disasters arising from the construction of reservoirs are:

1. Cause the rise of the groundwater level. In arid and semi-arid regions, rising water tables can lead to soil salinization. In humid areas, cold springs may cause invasion of fertile fields.

2. Large reservoirs may trigger**.

3. After the completion of the barrage dam, the sedimentary environment of the river may be changed due to the decrease in the flow rate of the upstream river section, which may cause the change of the channel of the channel.

4. If the dam fails under the action of force majeure, it will cause a catastrophe to the downstream.

5. It may affect the reproduction of migratory fish.

It is said that the reservoir will increase the bearing capacity of the formation, which is very easy to induce**. It can have an impact on the migration and spawning of some aquatic organisms, and will have some impact on the ecological environment.

It will change the atmospheric environment in a small area, increase air humidity, and induce ** if the reservoir is located on a fault zone.

The establishment of reservoirs on rivers will cause damage to the ecological environment and affect the return of fish to spawn.

It has a great impact on the environment. Water conservancy projects not only have an impact on the economy and society of the region where they are located through their construction tasks, but also have varying degrees of impact on the natural appearance, ecological environment, natural landscape, and even regional climate of rivers, lakes and nearby areas. There are advantages and disadvantages to this kind of impact, and it is necessary to fully estimate this impact when planning and designing, and strive to give play to the positive role of water conservancy projects and eliminate their negative impacts.

Flooding will be reduced.

1.Increase the frequency of geological disasters in the reservoir area.

The construction of a reservoir may induce an increase in the frequency of occurrence in the reservoir area and nearby areas. The frequency of landslides, landslides and debris flows will increase due to the long-term immersion of the lower part of the mountain on both sides of the reservoir in the mountainous area.

2.Resulting in sediment accumulation in the reservoir area.

Due to the interception of the dam, the slowing of the water potential and the backwater in the reservoir tail area, the sediment will inevitably accumulate in the reservoir, especially the dam and the reservoir tail (the influence of the backwater).

3.Soil salinization of downstream land.

Constant irrigation raises the water table, bringing salt from deep soils to the surface, which, combined with the high levels of salinity and various chemical residues in the irrigation water, leads to soil salinization.

4.Water quality in the reservoir area and downstream has deteriorated.

The reservoir area has a large water surface area, a large amount of water is evaporated, and the salinization of the soil increases the salinity and chemical residues in the soil, thereby polluting the groundwater and increasing the salinity of the downstream river water.

5.Changes in the quality of river water.

Due to the deterioration of water quality and the slowing down of water flow, aquatic plants and algae spread everywhere, which not only evaporated a large amount of river water, but also blocked river irrigation canals. These aquatic plants are not only found in irrigation channels, but also invade the main river channels. They hinder the efficient operation of irrigation canals and require frequent mechanical or chemical cleaning.

In this way, the maintenance of the irrigation system is increased.

6.Impacts on downstream river channels.

Due to the change of water potential and sediment content, the flow direction and alluvial degree of the downstream river section may also be changed, resulting in serious erosion and erosion of the riverbed, and the estuary of the river (sea) retreats to the land.

7.The incidence of downstream epidemics such as schistosomiasis increases due to the static flow of water.

8.The issue of migration and its impact on the scenery and cultural relics of the reservoir area.

Migration was required due to the inundation of the reservoir area due to rising water levels. In addition, due to the construction of the reservoir, the scenic spots and cultural relics in the reservoir area were submerged, and it was necessary to relocate and restore them.

9.Impact on the climate.

After the reservoir area is impounded, the water area expands and the evaporation of water increases, so the temperature difference between day and night in the nearby areas will be reduced, and the climate and environment of the reservoir area will be changed.

1. Block the water cycle.

The water cycle refers to the process of continuous movement of water in the hydrosphere, atmosphere, lithosphere, and biosphere through evaporation, plant transpiration, water vapor transport, precipitation, surface runoff, infiltration, and underground runoff. Rivers are the lifeblood of the earth and an important carrier of surface runoff in the water cycle. The construction of reservoirs has changed the amount of runoff in rivers, causing some rivers to be blocked or even disappearing, which in turn has blocked the water cycle to a certain extent.

The frequent breakdowns of the Yellow River in recent years are a direct consequence of the construction of multiple reservoirs on the river.

2. Destroying the ecological balance of the original area.

The construction of the reservoir has destroyed the original ecological balance of the region. On the one hand, reservoirs have flooded large areas of land, and the habitats of original terrestrial animals and plants have been covered by water, destroying the animal and plant resources that depend on these terrestrial habitats for survival and growth. On the other hand, dams in reservoirs block the migratory passage of migratory fish, which has a devastating effect on the exchange of species.

3. Destroying the ecological environment of the river itself.

The construction of the reservoir has destroyed the ecological environment of the river itself. For the downstream of the reservoir, the flow of water in the river is reduced, and the lack of water nourishment and protection in the river channel leads to the displacement of the river channel and the accumulation of silt, which reduces the flood control capacity, and at the same time the loss of many freshwater species that depend on it. For the upstream of the reservoir, a large amount of sediment and nutrients are deposited with the decrease of water flow rate, which in turn produces algae squeak and multiplication, and even causes the water body to become odorous and eutrophicated, and in some areas, it also increases the risk of schistosomiasis.

Fourth, change the climate and environment.

On the one hand, after the reservoir is impounded, the water area will expand, which will lead to the increase of water evaporation, thereby narrowing the temperature difference in the surrounding areas and changing the climate and environment of the surrounding areas. On the other hand, reservoirs have changed the water cycle to a certain extent, which in turn has also changed groundwater and precipitation.

Fifth, cause geological disasters such as **.

Due to the impoundment of water in the reservoir, the lower part of the original mountain has been soaked for a long time, causing or increasing geological disasters such as landslides, landslides, and debris flows. The most harmful of the geological disasters caused by reservoirs is called reservoirs. The impoundment of water in the reservoir causes the stress concentration and energy release in the rock mass, and the compressive stress and shear stress generated by the load of the water body destroy the crustal stress balance and cause fault dislocation, which is the direct cause of the first generation.

Reservoirs** mostly occur in areas where geological structures are relatively active. The magnitude and frequency of reservoirs in weak seismic areas will be higher than historical levels, while reservoirs in non-seismic areas may produce significant activities after impoundment.

The construction of the reservoir has a certain impact on the local environment, first of all, it can regulate the atmosphere around the reservoir, and has the effect of humidification. It cools down in the summer and warms up in the winter. In general, regional climatic conditions are controlled by atmospheric circulation, but after the construction of large and medium-sized reservoirs and irrigation projects, the original land becomes water bodies or wetlands, which makes the local surface air humid and has a certain impact on the local microclimate, mainly in the influence of meteorological factors such as rainfall, temperature, wind, and fog [1].

1. 1.1 Effect on rainfall.

1) Increased rainfall: This is caused by the construction of reservoirs that have created large areas of water storage, and under the radiation of sunlight, the amount of evaporation increases.

2) Change of rainfall distribution: The influence of low temperature effect of reservoir can change the distribution of rainfall, and the evaporation in the reservoir area will increase and the air will become humid. The measured data show that the rainfall in the reservoir area and adjacent areas has decreased, while the rainfall in the peripheral areas at a certain distance has increased, and in general, the rainfall on the windward side of the high terrain has increased, while the rainfall on the leeward side has decreased.

3) The distribution of rainfall time changes: for large reservoirs in southern China, the water surface temperature is lower than the air temperature in summer, the atmosphere is stable, the atmospheric convection is weakened, and the rainfall decreases. However, in winter, the water surface is warmer, atmospheric convection is enhanced, and rainfall increases.

1. 1.2 Effect on air temperature.

After the completion of the reservoir, the underlying surface of the reservoir area changed from land surface to water surface, and the energy exchange mode and intensity with the air changed, resulting in a change in temperature, and the annual average temperature increased slightly.

1.2 Effects on hydrology.

The construction of the reservoir changed the flow process of the downstream river, which affected the surrounding environment. The reservoir not only stores the flood season flood, but also intercepts the base flow in the non-flood season, which often makes the downstream river water level drop greatly or even cut off, and causes the surrounding groundwater level to drop, thus bringing a series of environmental and ecological problems: the downstream natural lakes or ponds are cut off from water and dry up; declining groundwater levels in downstream areas; The estuary siltation caused by the decrease in the flow of the river in the estuary caused by the inflow of seawater, resulting in seawater inflow; Due to the decrease in river flow, the self-purification capacity of the river is reduced; Reservoirs mainly used for power generation mostly serve as peak loads in the power system, and the diurnal variation of the discharge flow is large, resulting in a large change in the water level of the downstream river, which has a great impact on shipping, irrigation diversion level and fish farming. When the water level of the downstream river of the reservoir drops significantly and the flow of water is cut off, it will inevitably lead to the deterioration of water quality.

The adverse effects of reservoirs on ecology and environment mainly include the following aspects: (1) destroying and changing the unique functions and structures of watershed ecosystems; (2) Eutrophication or poisoning of water quality in the reservoir area; (3) changing the sediment sedimentation pattern, resulting in the shrinkage of the estuarine and bay flood plain and the erosion of the coastline; (4) the downstream channel of the dam is cut down, the river bank is eroded, and the salinity in the river and estuary water increases; (5) It is possible to induce landslides and landslides in the reservoir area; (6) Irrigation caused soil fertility loss and aggravated salinization; (7) lead to the reduction or destruction of vegetation or biological species; (8) The invasion of alien species leads to ecological harm; (9) Submerging cultural relics and monuments or causing loss of the ornamental value of the original natural landscape; (10) Impact on local traditional culture; (11) Induce a number of infectious diseases related to water bodies.

The construction of reservoirs, the storage of water resources, the use of water to ensure production and domestic use, and the use of electricity can also be used to generate electricity, these are all favorable factors for the construction of reservoirs.

However, the construction of reservoirs also has many adverse effects. ......Specifically, the more significant adverse effects are as follows.

1. Affect the local environment.

The state of the environment in any place is the result of long-term biological evolution and environmental changes, and it is a relatively stable state. ......After the construction of the reservoir, the local vegetation will be submerged, and a large amount of water will appear in the local environment, which will have a significant impact on the local environment.

2. Affect biological migration and migration.

Many organisms are regularly migratory, migratory organisms that need to move back and forth over a wide area.

When there is no reservoir, these creatures can roam freely.

With the reservoirs, the migratory paths of these organisms are blocked, and they are unable to migrate and migrate. ......This will have serious consequences.

3. The huge weight of the large amount of water contained in the reservoir will form a huge pressure on the local crust, which may induce the anomaly of the local geological fault zone and induce disasters such as **.

When building a reservoir, the following adverse effects are generally caused.

1. For inland rivers, the reduction of wetland area may lead to the destruction of downstream ecology. 2. For outflow rivers, the reservoir can reduce the water level of the downstream and reduce the amount of sediment, resulting in a deep cut of the riverbed, resulting in an increase in the salinity of the estuary, an increase in the salinity of groundwater, and salinization of the land.

3. In addition, there will be sediment accumulation in the reservoir area, and geological disasters may occur.

4. To be resettled, the rising water level in the reservoir area may inundate the monuments, and the rise in the water level may have an impact on the rivers above the dam.

The construction of reservoirs will raise the water level in some areas. Drowned a lot of good crops. It can also cause a change in the water quality of a local area.

But in general, build a reservoir. utilization. It's better than not building one reservoir and moving another.

If you send a part of the play, you can get a part, and you can get more in comparison.

The adverse effects of dams on ecology and environment mainly include the following aspects: (1) destroying and changing the unique functions and structures of watershed ecosystems; (2) Eutrophication or poisoning of water quality in the reservoir area; (3) changing the sediment sedimentation pattern, resulting in the shrinkage of the estuarine and bay flood plain and the erosion of the coastline; (4) the downstream channel of the dam is cut down, the river bank is eroded, and the salinity in the river and estuary water increases; (5) It is possible to induce landslides and landslides in the reservoir area; (6) Irrigation caused soil fertility loss and aggravated salinization; (7) lead to the reduction or destruction of vegetation or biological species; (8) The invasion of alien species leads to ecological harm; (9) Submerging cultural relics and monuments or causing loss of the ornamental value of the original natural landscape; (10) Impact on local traditional culture; (11) Induce a number of infectious diseases related to water bodies.

As a result, a large area of land will be inundated, resulting in the loss of land resources.

If the geological structure of the reservoir area is not good, large-capacity water storage may also cause **.

The adverse effects of dams on ecology and environment mainly include the following aspects: (1) destroying and changing the unique functions and structures of watershed ecosystems; (2) Eutrophication or poisoning of water quality in the reservoir area; (3) changing the sediment sedimentation pattern, resulting in the shrinkage of the estuarine and bay flood plain and the erosion of the coastline; (4) the downstream channel of the dam is cut down, the river bank is eroded, and the salinity in the river and estuary water increases; (5) It is possible to induce landslides and landslides in the reservoir area; (6) Irrigation caused soil fertility loss and aggravated salinization; (7) lead to the reduction or destruction of vegetation or biological species; (8) The invasion of alien species leads to ecological harm; (9) Submerging cultural relics and monuments or causing loss of the ornamental value of the original natural landscape; (10) Impact on local traditional culture; (11) Induce a number of infectious diseases related to water bodies.