Building is a large cause of loss of habitat, towns and cities are outwardly expanding and more land is being used for housing and other large scale building projects such as shopping malls and new roads. Draining of swamps and wetlands and deforestation are also greatly contributed to by building. Loss of habitat and habitat fragmentation are areas of major concern in species conservation, building often results in large areas of habitat being broken up into a series of smaller areas, each of which will support fewer species.
(Building site)
Farming and agriculture reduce amounts of land and lead to loss of habitat because of an increasing need for larger fields which had led to the removal of hedgerows and wildlife habitats. Increasing numbers of livestock has meant that larger grazing areas are needed which causes soil erosion and exhaustion, leading to a loss of habitat for some plants. In some areas, areas of woodland and have been destroyed to make room for expanding farmland.
“The catalogue of destruction of Britain's wildlife and habitat makes depressing reading. Figures reveal that since the Second World War, Britain has lost:
95% of traditional hay meadows;
99% of lowland heaths;
80% of chalk downland;
80% of limestone grasslands;
80% of fens and mires;
90% of lowland ponds;
50% of ancient lowland woods;
150,000 miles of hedgerows.”
(Countryside Commission 2000)
Waste dumping, whether illegal "fly-tipping" or landfill, releases gasses and some illegal dumps, whilst small in size can be serious, particularly if hazardous waste is involved. Toxins can be leached into the soil from the waste which can seriously affect the land for animals and plants in the area. Biodegradable waste that is dumped causes a huge problem by producing the flammable gas methane which contributes to global warming.
Human Activities
Human activities pollute air, water and land in different ways.
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Oil spills are becoming a large scale problem, causing devastating effects to marine wildlife. The oil is almost impossible to clean up, spreading over large areas very quickly. Even solutions designed to dissolve the oil can cause an imbalance in the ocean environment. Much water pollution is also caused by sewage and fertilizers seeping into water and starting the process of eutrophication by encouraging the growth of aquatic plants and algae. This process quickly blocks waterways, uses up oxygen and blocks light to deeper water. When this occurs, it kills aquatic organisms in large numbers which leads to disruptions in the food chain.
Many industrial and power plants use rivers, streams and lakes to dispose of waste heat. The introduction of hotter water can lead to thermal pollution. Thermal pollution can have a highly negative effect on life in an aquatic ecosystem as a temperature increase will decrease the amount of oxygen in the water. This reduces the number of living things that can survive there. Water can also become contaminated with toxic or radioactive materials from industry, mine sites and abandoned hazardous waste sites.
Even hazardous chemical waste from the home improperly disposed of down drains can introduce toxic chemicals into the ecosystem.
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The Greenhouse Effect comes from the build up of carbon dioxide in the atmosphere. Carbon dioxide is produced when fuels are burned and plants convert carbon dioxide back to oxygen, but the release of carbon dioxide from human activities is higher than the world's plants can convert. The situation is made worse since many of the earth's forests are being destroyed, and plant life is being damaged by acid rain. Therefore the amount of carbon dioxide in the air is continuing to increase. This buildup acts like a blanket and traps heat close to the surface of the Earth. Changes of even a few degrees will affect the whole planet through changes in the climate.
Acid Rain is caused by emissions from industries which burn fossil fuels. Sulphur dioxide
Solutions
- Many Conservationist organizations are finding ways to minimise and combat the negative effects that Man is having on the environment.
Oil pollution is a growing problem being addressed by Greenpeace, in protest to drilling for oil and by continuing to combat the effects of oil spills.
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The use of compost in agriculture is a way of maintaining or restoring the quality of soils because of the properties of the organic matter contained in the compost. It is a valuable method of tackling organic matter depletion and soil erosion in southern europe as well as in areas continuously used in arable production where organic matter levels are decreasing.
- The Countryside and Rights of Way Act was passed on 30th November 2000. This legislation puts into place additional safeguards for the most precious wildlife habitats and endangered species.
- Strict guidelines have been set to reduce emissions contributing to global warming and to increase recycling in Britain.