Effects of dams on river ecosystems

Effects of dams on river ecosystems

dams are extremely useful for humans - they offer drinking water solutions, help with flood control, support irrigation for agricultural purposes and even create renewable energy - but their influence on the river ecosystems can be enormous. The effects range from changing the water flow to the impairment of fish populations and other aquatic life forms. This article examines how dams influence the river ecosystems, the consequences that result from it and what can be done to alleviate potential harmful effects.

The change in the water flow

Interruption of the natural river

The main function of dams is to hold back water and control the water flow. As a result, the natural flow course of the river is interrupted. A natural flow has high and low water phases that determine the functioning of the entire ecosystem and ensure the survival of many species. Such an interruption disturbs both the water quality and the amount of the available habitat.

reduced river fill

Since dams store water in a reservoir, the water flow leading down the river is reduced. This reduced drainage rate can change the river bed, build sediments and impair important river landscapes such as wetlands and river mouths.

The effects on water quality

temperature change

Dams can change the water temperature in a river. Since the water on the bottom of the reservoir is cooler than that on the surface, the drain underneath can be cold than in a natural flow. This can negatively influence the survival rates of species that are dependent on certain water temperatures.

oxygen deficiency

The amount of water in the river plays a crucial role in the oxygen content of the water. Reduced amounts of river can reduce the oxygen content of the water, which can make breathing of aquatic living things more difficult.

effects on aquatic biodiversity

fragmentation of the habitat

Storaems form physical barriers in river systems that influence the moving of species in the water. This phenomenon is known as a habitat fragmentation and has a significant impact on river ecosystems.

Effects on hiking fish

Many types of fish, such as salmon and eels, are hiking species that move back and forth between sweet and salt water in different stages of life. The physical barrier created by the dam can significantly impair the ability of these species to carry out their migration and achieve important habitat areas.

reduction strategies to reduce the effects of dams

Despite the negative effects of dams on river ecosystems, they are still an important resource of humanity. Therefore, various reduction strategies were developed to reduce the negative effects on the environment.

Improvement of continuousness

A strategy to reduce the effects of dams on the river ecosystem is to improve the continuousness for wandering fish populations. This can be achieved with fish paths or fish stairs that enable fishing the passage around the dam.

Adjustment of water withdrawal and release

Another option is to adapt the water withdrawal and release to the natural rhythm of the river. This could simulate high and low water phases that support the natural life cycle of many species in the river.

conclusion

Downs clearly have significant effects on river ecosystems, from changing the water flow and water quality to the impairment of fish populations and aquatic habitats. While dams bring considerable benefits for humans, it is important to reduce their environmental impacts and develop methods in order to reduce their negative effects on the river ecosystems. The ultimate goal of finding a balance between the human requirements and the protection of the biodiversity and health of our river ecosystems.