Water is one of the main resources, without which there would be no life on Earth. No one thinks about water, until it becomes scarce. There are several areas around the world known for centuries for their water shortages, like the African and Asian deserts. However, the severe droughts happening recently in many parts of the world, like the one in the Amazon basin in 2005, brought the water issue to the main view.
Drought affects all areas of our lives. The degradation of the land and its ecosystems as a result of prolonged drought is called desertification. Its consequences are multiple and severe and can be divided into three major categories: economic, social and environmental. Economic and social effects of drought are directly or indirectly induced by the environmental situation. Therefore we will focus on the environmental consequences of desertification.
Long period of reduced precipitation, also called meteorological drought, has a direct impact on plant life. Many plant species, that rely on high moisture, die back and even are eliminated by stronger, more water thrifty plants. It is all present in farming. Crops, that aren't watered enough, are weakened and become infested by weeds. Deciduous forests are another example. Most deciduous trees need a lot of moisture. They exclusively rely on precipitation and without it they cannot thrive. Disappearance of trees and bushes, on the other hand, further increases the vulnerability of the land.
Prolonged meteorological drought leads to hydrological drought, which is a decrease in water reserves. Snow packs in the mountains usually feed springs and rivers that provide water for large areas. Low snow accumulation can cause reduced water flow and even drying up some of the springs and smaller rivers. Long periods of drought also means lower water levels in reservoirs, lakes, ponds, and wetlands. It causes decreased population of fish and other aquatic life. That, in turn, negatively affects the supply of food for people, as well as animals.
Lower water levels have a major impact on agriculture, causing an agricultural drought. The result is a substantial reduction in crop production, soil erosion, and lower overall food production. Pest infestation can become a problem, like for example increased wasp and hornet infestation in fruit orchards, where they feed on fruit in lack of other sources of water. However, increased use of pesticides can cause water contamination and poisoning of humans as well as animals.
Increased need for watering and providing water to urban areas leads to groundwater depletion. This can cause decrease in water quality, as a result of higher salt concentration, increased water temperature, turbidity, acidity, etc.
Prolonged drought spells have a negative impact on animals. Forest, grassland and wetland degradation can lead to reduction of wildlife, because of the changes and sometimes the destruction of their natural habitat. In response to shortages of available food and water, wild animals will often migrate to other areas, not affected by drought, causing overpopulation in those areas. They often invade farming lands in search of nourishment and are likely to be killed by farmers protecting their crops and livestock. Undernourished and dehydrated animals are prone to disease as their immune system weakens. They can spread disease onto the farm, and vice versa, the farm livestock can cause the infection of wild animals. Weak animals are much more vulnerable to predators. Severe shortages of water will result in higher wildlife mortality, including endangered species, and in the end, loss of biodiversity.
Other environmental consequences that affect all aspects of our lives are:
- Increase number and severity if wildfires.
- Soil erosion and poor soil quality.
- Decreased air quality.
- Visual and landscape quality.
The environmental consequences of drought have a tremendous impact on economy, our health, and even on politics (water right fights). The costs are so high, that many countries make an effort to monitor and prepare for drought to prevent desertification. Although, it is not just the authorities who are responsible for our water. All the people, all over the world, need to not only be aware, but also make an effort to protect this life giving resource.