Tento článok bol vytlačený zo stránky https://referaty.centrum.sk

 

The human race and nature

Human has been being inseparable element of nature since it’s beginning. He is now the most intelligent creature on the Earth. He uses intelect for his gain. But sometimes he forgets on other inhabitants of the Earth. They need to be here, because people depend on them. Nature has got many secrets and it hides treasures like natural gas, coal, ores, black gold – crude oil and many others. Human uses it in his everyday life, but he doesn’t relize, that one day this recources won’t exist. People should think forward and live their life for next generations.

Main elements of nature:
·Air – It’s a mix of gasses and the oxigen is the most important gas. We need to breathe and we wouldn’t be able to live, if we hadn’t got any oxigen. It is created by plants during photosynthesis. So this is the reason why we need forests- they are lungs of Earth. The quality of air has gone down after industrial revolution, because it was using a lot of coal for steam machines. Nowadays we don’t use as much coal as in the past, but air is polluted by exhalates from cars and factories.
·Water – This valuable liquid surrounds us and covers nearly three quarters of planet. We can use only small part of it for drinking, because main nubmber of water is created by oceans and seas. Oceans and seas offer surround for many animals and water plants. Fish are source of food for people. Water area is place for transport by ships. Sometimes there are some accidents, which are caused by tanker ships. Oil from ship covers water surface and kills all living creatures. Number of people rises every day and there is no water for everyone. Some areas like in Africa has got problems with drinkable water and people die for thirst and diseases which are hidden in contamined water.

·Soil – contains materials which are reqired for growth of plants. These materials are created by decaying of organism. Chemical waste pollutes soil and mades it unusable. Quality of soil goes down because of erosion and deserts accreation. Farmers want to increase quality of soil with using fertilizers but they pollute groundwater and fertizilers substancies (nitrates) get into plants. Higher number of these substances can be dangerous for human organism.

Pollution
Pollution is a side product of modern human life. Actual problems are ozone gap, greenhouse effect, acid rains and waste.
Ozone layer is a layer around the Earth and it’s created by three molecules of oxigen (ozone). It protects Earth from ultraviolett light, which comes from the Sun. Freon gases has got influence on ozone layer and create ozone gap. Freons are used in refregerators and sprays.UV rays can cause skin cancer and eye problems. We can stop thinning ozone layer, if we don’t use freons.

Greenhouse effect causes rising temperature on planet. Higher temperature causes melting glaciers and moving climatic zones. And this is the reason why snow doesn’t fall in winter and it only rains and temperature is higher than before. Melted glaciers rise level of oceans. Scientists suppose that areas on coast will be flooded in future. Greenhouse effect is caused by greenhouse gases. These gases are carbon dioxide and methane. They are created in cars and during burning. They don’t allow to leak heat from atmosphere to space.
Acid rains are dangerous for all forests, plants and buildings too. How does it start? Acid gases (sulfur dioxide) are let out from factory and they mix with rain clouds. Water and acid gas create acid, which falls down as a rain. Acid damages leafs and masonry. Many historical sculptures were damaged by acid rains and they were replaced by copies.

Everyone knows trash. It is something unnecesary and useless. It’s created every day. We put it into wastebasket then basket is emptied and waste is transported out. We know many ways of waste destrucion. We burn it, put on dump, compost and recycle. These methods have got pros and cons. By burning we get rid of waste and we can use heat energy for heating, but it’s created harmful gases. Putting on dump is the cheapest way how to get rid of it, but it takes too much place. Composting and recycling are considerate to be good for nature. By composting we create manure and it can be used in gardens. By recycling we can give one more chance to waste and it can be used again. We can recycle paper, glass, metals and rubber from tyres. Scientists found out how to recycle plastic products, because number of it is rising and it’s not easy to process it.

People want to prevent pollution because it brings health problems and endangers human race in future. They search for new technologies. Organisations like Greenpeace fight against big companies, which pollute the nature. Politics make new laws, which might save nature. New aternative power sources will supplant old and pollutive sources. Cars will use water instead of fuel and electricity will be made by sollar powerstations and hydro-electric power plants, because natural resources aren’t endless. We should reduce usage of products, which contains freons and greenhouse gases. We should teach young people to recycle and how to save nature.
In my opinion we should change our life and help nature, because we need nature and nature needs us. Our life shouldn’t be egoistic and centered for our comfort.

Koniec vytlačenej stránky z https://referaty.centrum.sk