Water: a challenge of the 21st century

Without water there is no life. Water covers 3 quarters of the earth surface and it is essential for the human basic needs (such as health and food) and for the farming activities. It has a crucial influence in the quality of human life and the maintenance of the ecosystems.

In our planet, there is 97% water in the oceans, in the clouds, in rain, in rivers, etc, but only 3% is consumable. Nowadays, in our world, with the growth of population, the consumption of water will increase, and also its demand, which will lead to an excessive use of it.

“At this moment, about 1,1 billions of people have no access to drinkable water. With the global warming this number will increase. It is predicted that within the next 40 years, about 2 billions of people will be affected by the lack of water. And this is a positive hypothesis. In the worst, will be affected 7 billions of people. “ (http://magus.blogs.sapo.pt/9254.html)

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Global Warming

Global warming is on of the most concerning problems that we are nowadays confronting. The earth’s climate is a very complicated system. Now it is widely recognised that human activity is having a negative effect on it. The pollution which results from the use of oil and coal in industry, as well as the increased of use private cars, is causing significant changes in temperature in many parts of the world. These changes often have a knock-on effect on other aspects of the climate, leading to things like extreme weather conditions, rising sea levels and the extinction of many species, as a result of climate change.

A much more serious problem is how to prevent the situation from getting even worse. This depends on how quickly the number of population grows. Although many countries have agreed to try to limit the population they "create", much more things have to be done.
If we do not do anything, the temperatures are set to rise by about 0,2% per decade, during the 21st century. Such a rate of warming is bigger than anything that has occurred over the last ten thousand years. “During the entire 20th century, the average global temperature increased by about 0.6 degrees Celsius (slightly more than 1 degree Fahrenheit).”

sources:

Ontem e hoje, física 10 - porto editora

Sustentabilidade na terra, ciências naturais - areal editores

http://environment.about.com/od/globalwarming/a/greenhouse.htm

Importance of water

Water is a fount very precios for a human, animal and plant survival. It is used at all type of human activities. Human's body is constitued by 75% of water, which turn it indispensable for celular life. Each person need drink 2L of water per day. It regulates body's temperature and cut off toxins through urine and perspiration. It's also very important for good kidney working. Each person spend every day near 200L of water for her needs. Unfortunately a big part of these water is wasted because of an incorect use.

Afrca is mainland which has a great lack of water. Inhabitants of that continent have very difficult acess to that fount, because of that and with a lack of the sanitation condition die million people and 90% of them are children. In countries with lack of water , diarrhoea is more frequent and is a second diseasethat provoke a great number of deads.

More developed countries already use apropriate machines for ocean's water distillation. This's just one of many others solutions of this problem.

Everyone , humans, animals and plants wouldn't survived without water.

Be smart and think in your future. Save water because it is our life. Where there is no water, there is no life.http://www.gippswater.com.au/Portals/0/Water_Restrictions_reduceyouruse_logo.jpg

Pollution

Principal problem that worry a lot of people today is pollution. Pollution can be defined as introduction in the environment of any material or energy that modifieds some characteristics of the Earth. We are principal pollutant, humans, it's true that exist natural pollutions, but this doesn't contibute such a way how human activities, for a changing of the Earth. Indudtries, agricultural processes and car emissions are activities with higest pollution values. If all people stop for think, they will rearch than they are destroing themself. Each day that is spend Earth suffer lots of changes that become more and more dangerous for human health, for animal survival and plants growth. Every day dimillion people because of incurable diseases that result of pollution. Plastics bags, bateries and glass are things that carry many years for decompose. In case of the bateries they carry more time for decompose and break loose very dangerous liquids.

There are some kind of pollution as:

• Ground pollution;


• Atmosphere pollution;


• Water pollution;


• Sound pollution;


• Visual pollution;


• ... and others.

Counties that pollute more are U.S.A. and China. In the U.S.A. air than people breathe is equivalent to smoking 2 packs of sigarets pr day.

Recycle, Reduce and Reuse!

Nature preservation

Nature preservation is a necessety to avoid endangered espicies and plants. How we know, a cause of endangered espicies is destruction of their habitats, ilegal dealing, killings because of our down, skin valuable and finally because of pollution. The manner of Man manages the Earth show disrespect that he has by Earth and by himself. Since Man has appeared on the Earth he made many environmental changes with a consequence of growing of animal dies. Nowadays animals are more agressive with people because we provoke them. If we preservate nature we will live better, will lessen number of deads. Nowadays die lots of people and animals because humans pollute more and wasted natural resources.

When you abate trees in one local you can plant it in another.

http://media.photobucket.com/image/preservation%20of%20Earth/phets/soctecad1.jpg

Importance of plants in our life

Plants are also considered living beings because they consume water and they breathe. Plants are essencial for the life on Earth, but today there are less greens spaces because of the buildings. Humans use plants as food, some we use directly and others we "transform" for latest using. Plant are used not only how food but also avail for medicine. More than half of remedies have plants extracts.The most important function of plants is absorve CO2 and to release O2, that is essencial for the life. These one can be also use for produce scent. Lumber is used in buildings, produce fibers than are used in textile industry, etc.

Take care of the plants!
Raise more trees, because they are essencial for our life!

http://www.travelblog.org/Photos/1880836.html

Deforestation

Deforestation is the process of disappearance of large pieces of forest, which is caused by human activities, such as the exploitation of raw material or building (which is considered economically more profitable than having a group living creatures that control the water and soil cycles and recycle the air producing oxygen.

Deforestation in a large scale also contributes for the emission of CO2 to the atmosphere (about 10 to 30% a year). This is one of the main gases involved in the global warming of the planet. On the other hand, the growing forests remove CO2 from the atmosphere fixing it in the soil and in the trees.

The biggest forest in the world known as “the earth lung”, for the amount of oxygen it produces, is the Amazonia, located in South America. This forest is disappearing by human action and its destruction, along with increasing the level of the carbon dioxide and reducing the levels of oxygen in the atmosphere, is also leading to the extinction of animal and vegetal species.

http://www.youtube.com/watch?v=2EHSUnYwVFA&feature=fvsr