POLLUTION

موضوع: POLLUTION الجمعة أبريل 10, 2009 12:51 pm

Pollution is the introduction of contaminants into an environment ‎that causes instability, disorder, harm or discomfort to the ‎ecosystem i.e. physical systems or living organisms . Pollution can ‎take the form of chemical substances, or energy, such as noise, ‎heat, or light energy. Pollutants, the elements of pollution, can be ‎foreign substances or energies, or naturally occurring; when ‎naturally occurring, they are considered contaminants when they ‎exceed natural levels. Pollution is often classed as point source or ‎nonpoint source pollution. The Blacksmith Institute issues ‎annually a list of the world's worst polluted places. In the 2007 ‎issues the ten top nominees are located in Azerbaijan, China, ‎India, Peru, Russia, Ukraine and Zambia.‎

Water pollution is the contamination of water bodies such as ‎lakes, rivers, oceans, and groundwater caused by human activities, ‎which can be harmful to organisms and plants that live in these ‎water bodies

Air is the ocean we breathe. Air supplies us with oxygen, which is ‎essential for our bodies to live. Air is 99.9% nitrogen, oxygen, ‎water vapor and inert gases. Human activities can release ‎substances into the air, some of which can cause problems for ‎humans, plants, and animals. There are several main types of ‎pollution and well-known effects of pollution, which are commonly ‎discussed. These include smog, acid rain, the greenhouse effect, ‎and "holes" in the ozone layer. Each of these problems has serious ‎implications for our health and well-being as well as for the whole ‎environment. One type of air pollution is the release of particles ‎into the air from burning fuel for energy. Diesel smoke is a good ‎example of this particulate matter. The particles are very small ‎pieces of matter measuring about 2.5 microns or about .0001 ‎inches. This type of pollution is sometimes referred to as "black ‎carbon" pollution. The exhaust from burning fuels in automobiles, ‎homes, and industries is a major source of pollution in the air. ‎Some authorities believe that even the burning of wood and ‎charcoal in fireplaces and barbeques can release significant ‎quantities of soot into the air. Another type of pollution is the ‎release of noxious gases, such as sulfur dioxide, carbon ‎monoxide, nitrogen oxides, and chemical vapors. These can take ‎part in further chemical reactions once they are in the ‎atmosphere, forming smog and acid rain. Pollution also needs to be ‎considered inside our homes, offices, and schools. Some of these ‎pollutants can be created by indoor activities such as smoking and ‎cooking. In the United States, we spend about 80-90% of our ‎time inside buildings, and so our exposure to harmful indoor ‎pollutants can be serious. It is therefore important to consider ‎both indoor and outdoor air pollution. ‎

موضوع: رد: POLLUTION الأربعاء أبريل 15, 2009 6:28 pm

شكرا يا بسمة علي هذا الموضوع الرائع

موضوع: رد: POLLUTION الخميس أبريل 23, 2009 4:28 pm

موضوع: رد: POLLUTION الإثنين أبريل 27, 2009 7:03 pm

Thnx Basma

موضوع: رد: POLLUTION الأربعاء سبتمبر 02, 2009 4:59 am