Mans Effect On The Environment Essay
1) SOURCES OF POLLUTION
Freshwater Environments : Man pollutes freshwater all over the world in many ways there is much waste and pollution that ends up in rivers.
One of the main hazards is called eutrophication, this process becomes enriched with artificial nutrients from fertilisers which run off into the rivers and upset the natural nutrient cycle of the river, lake or pond. The water turns green because of the algae which when they die multifly using up all the oxygen.
Similar consequences occur if raw sewage is pumped into a river.
Chemical waste from factories dump their un wanted waste into rivers, lakes or ponds as well. One major component that effects the water wildlife is the insecticide DDT which damages animal tissue and is dangerous to humans, this can be passed along the foodchain.
Marine Environments: 80% of the waste which is pumped into the sea each year is produced by dredging, 10% is industrial waste and 10% is sewage. Some of the consiquences due to this are :- presence of toxic substances and the rapid uptake of contaminants by marine organisms to name but a few. Oil spillages either by tankers or offshore ridges cause
Agricultural Environments: Unwanted plants or insects are nowadays killed with by herbicides and insecticides, in this case chemical rather than biological are used. Pesticides have the ability to damage the local environment, while herbicides may kill wild flowers as well as weeds and insecticides may kill harmful pests but it can also kill butterflies and moths. Some of these chemicals are even dangerous to humans as well.
2) FIVE MAJOR POLLUTANTS:
Sulphur Dioxide comes from both car and factory emissions.
Sulphur Dioxide is a poisonous gas which can kill plants and is the main gas that is involved in Acid Rain.
Oil can be spilt into our oceans by tankers and from Oilrigs themselves.
It is denser than water and therefore floats on it and is taken to shore by the sea. At this point the oil can seriously damage the beach and it’s wildlife eg fish.
The detergents that have been invented sometimes cause more damage than the oil itself but nowadays they use less destructive.
Lead is found in cars exhausts and some plants.
It can cause brain damage and various mental disabilities.
Lead free petrol are now used world wide.
Eutrophication from fertilisers running off the fields and into rivers and lakes causes abnormal plant growth.
It causes bad tatse, odours and algae and other things like precipitation of calcium carbonate.
Treatment in aerobic or anaerobic lagoons can control it.
This comes from factories which burn fossil fuels and from car emissions as well.
When reacted with sunlight, mosture and oxidants it produces sulphuric and nitric acids. These then get mixed up with the water cycle and fall to earth as Acid Rain.
Catalytic Converters are used in cars now to reduce the amount of harmful emissions given off. You can also use cleaner power such as Hydro and Nuclear which would also reduce the amount of harmful emissions given off.
3) ATMOSPHERE POLLUTION :
Global warming: Green house gases include : Carbon Dioxide released from
Combustion fossil fuels, Methane produced from ruminants- released from gut into atmosphere and CFC’s from aerosol cans. These gases which are infrared radiation are reflected toward’s the earth’s surface, this hot air becomes trapped in our troposphere creating global warming.
Because of global warming: –
High winds heavier rains
Polar ice caps melting and causing sea levels to rise.
Water evaporates from fertile area – crop losses
Extended range of pests
Although there are a lot of bad points the only good one is the fact that the rate of photosynthesis is increasing due to more carbon Dioxide and higher temperatures.
Ozone Depletion : the ozone absorbs solar ultraviolet radiation which causes sunburn, skin cancer, cataracts and damage to DNA.
Human effect on our planet effecting ozone levels
CFC’s-decreases amounts of our high level ozone layer eg used in aerosols.
Fossil fuel increases low level ozone as the ntrogen produced reacts with oxygen.
Low-level ozone causes problems by acting as a greenhouse gas which causes smog which in turn causes throat, eye and lung irritations and decreases crops by damaging mesophyll in leaves.
Acid Rain : This is caused by releasing such gases as Sulphur and nitrogen, unburned hydrocarbon fuels and oxides into the atmosphere.
The major problems caused by acid rain are as follows: –
Soils becoming acidic causing leaching and inhabitation of decay.
Food chains disrupted due to water in rivers and lakes collecting excessive amounts of minerals which kills living organisms eg fish.
Starvation of forest trees due to leaching of ions.
Catalytic converters are used on cars to reduce emissions and therefore cutting down acid rain. You can also use hydro and nuclear power to cut down the number of harmful emissions which factories pump into the atmosphere.
4) RECYCLING PROCESSE:
Compost : is the collection of organic plant material which are left to decay in compost heaps normally found in gardens or farms. The decayed material is full of nutrients and can be used on soils to increase their nutrient content of Nitrogen, Potassium and Phosphorus to make soil more fertile.
Organic fertilisers: is the avoidance of using synthetically produced fertilisers in the process of growing plants or crops. This is involved with recycling as crop residues, animal manure, green manure, farm organic wastes and composts to maintain soil productivity with maximum nutrient content. Other methods such as biological pest control, crop rotation and legumes are used in organic farming. This process is more common in developing and underdeveloped countries due to lack and cost of chemicals.
Recycling materials: the UK recycles 25% and 10% of all materials being recycled from the respective types of waste. The following list shows the materials which are most commonly recycled in the UK: –
Paper: newspapers, office papers and magazines are most commonly recycled.
Kris Charik R10D
Glass: bottles, glasses and jars are most commonly recycled with milk bottles being reused.
Metals: Aluminium cans are most commonly recycled with harder metals being more difficult to recycle. Aluminium is good because its easy to melt but if keeps the same quality when recycled.
Plastics: cause a big problem as it is difficult to identify and separate different types and a relatively low demand for the recycled marerial also adds to the problem.
Recycling is growing in popularity and the government hope that by the year 2000 50% of all household waste will be recycled.
DISPOSAL OF WASTE:
Lanfill: There are four critical elements in a secure landfill: a bottom liner, a leachate collection system, a cover, and the natural hydrogeologic setting. The natural setting can be selected to minimize the possibility of wastes escaping to groundwater beneath a landfill. The three other elements must be engineered. Each of these elements is critical to success. There are four critical elements in a secure landfill: a bottom liner, a leachate collection system, a cover, and the natural hydrogeologic setting. The natural setting can be selected to minimize the possibility of wastes escaping to groundwater beneath a landfill. The three other elements must be engineered. Each of these elements is critical to success. Plastics are the major problem with landfill sites as they will remain for thousands of years until they fully decompose.
Incineration: in conventionally designed incinerators, refuse is burned on moving gates in chambers : combustible gasses and the solids they carry are burned in the secondary chamber. The poducts of incineration include the primary products of combustion-carbon dioxide and water- as well as oxides of sulphur and nitrogen and other gaseous pollutants. Emissions of harmful ash and gasses are controlled by wet scrubbers, electrostatic precipitators and bag filters.
Dumping: harmful chemicals are dumped into dumpsites but if they seep into soil and water, the chemicals can contaminate water supplies, air, crops and domestic animals as well as these it can cause miscarriages and organic diseases.
Sewage: including water, faeces, urine, dtergants and various household items is pumped into sewage plants for treatment. Methane is produced and is burnt to power other machinery in the plant. Eventually pathogen free water is produced. The sludge can be sold as fertilisersused in landfill to aid decomposition, incinerated or dumped at sea.
Hospital waste is burnt to prevent spread of desease. FARM WASTE IS PUT INTO COMPOST HEAPS.
ABUSE OF RESOURCES:
The worlds supply of fossil fuels is running out due to the over use of them, and we are not producing other sorts of energy fast enough. This means that we are relying on fossil fuels too much without making use of other energy’s available to us such as Nuclear.
Over production of foods and energy which cannot be used fast enough sometimes become unusable and are wasted so we must slow down these production and harvest rates. We are producing so rapidly that not all of the product can be used up at once unless demand increases. When food and drink is produced too rapidly it just gets thrown either onto food mountains or drink lakes and are wasted. Too much is produced due to the fact that the producer must produce a maximum yield in order to make a pofit.
6) CONTROLLED USE OF EARTH’S RESOURCES
Mining: is a major problem as we are mining too fast with too much of what we mine being classified as waste as the demand is not high enough.
Deforestation: happening too fast, speeding up global warming. Wildlife are losing their homes and some species are becoming extinct. Trees should be planted in replace of those cut down. This would mean that landscapes would stay beautiful and it would also prevent the extinction of many species of different wildlife.
Over Fishing: this done by fisherman catching too many fish from one particular area and not replacing or giving them enough enough time to reproduce sufficiently. This eventually may cause extinction of some species.
Trapping: this when animals are cauhgt either for meat or fur or just because they are a nescence. Sometimes this is down to move one type of animal from one place to another or even for hunting eg shooting. Dear Stalking: this is when dear’s are hunted and killed for fun as a past time. This is similar to fox hunting as well.
Methane this a valuable fuel especially in the production of hydrogen, cyanide, ammonia and ethyne to name just a few. It’s colourless, odourless and is very flammable. Because it’s highly flammable poor countries like India can use it for power.
Peat this has a high carbon content and is brown in appearance. It’s built up by partial decay and carbonisation of vegetation in acid water in bogs. These are normally found in the U.S, Britain, Canada and Russia. It is not as efficient as coal as a fuel because it has a high water and ash content.
Wood this is a good Biofuel as it provides 13% of the world’s energy. As wood is used so much in the poorer countries and is insufficiently burnt resources are slowly decreasing in such countries as Africa and Asia. Nowadays there are special trees which can grow more quickly therefore it is possible in the right plants wood can produce substantial amounts of energy.
Alcohol can be made during fermentation and can be used in cars as fuel. It’s main advantage is that it is more enviromentaly friendly. It can also be used to make such things as perfumes, lacquer and explosives.
The Government wants more people to do more in the way of giving the poorer waste food and say that we should help them as much as we can. The government has also set up charities which raise money in order to give help to particulary the extremely poor countries by using T.V adverts to raise the money. Oxfam is possibly the most well known charity that helps poor countries, Oxfam however mainly helps such countries as India and Africa.