Natural resources (economically referred to as lan

The biotic resources can be obtained in the raw form, or by means of cultivation through agriculture. Petroleum is a resource included in the category of biotic natural resources; the organic origin or petroleum is the reason behind its inclusion in biotic resources. The following list provides names of resources directly obtained from the biosphere. Most of the biotic resources are non-renewable in nature. Petroleum and natural gas were formed through years of decomposition of organic matter. This organic matter included the remains of plants and animals. Therefore, the resources are categorized as biotic.

• Timber
• Petroleum
• Natural Gas
• Fruits
• Wax (tree wax)

Biotic Resources (Agriculture): Crops obtained through farming are the important natural resources. Few of the resources are given below.

• Rice, Wheat and Corn: These are the cereals widely used by people the world over. Wheat, rice and corn form the bulk of grains cultivated by farmers for consumption.
• Cotton: It is a cash crop which produces raw material for manufacturing of garments. Nowadays, even synthetic fibers are used for manufacturing garments, however, cotton holds the major share.
• Sugarcane: The sugarcane crop, just like cotton is considered a cash crop for farmers. Sugar prepared from its cane is used in a variety of food products. In fact, the bakery products and other sweetmeats require sugar as its basic ingredient.

The crops mentioned above are important ones. The list of other plants used for the purpose of cultivation is presented below.

• Parsley
• Oat
• Rye
• Basil
• Bay
• Cauliflower
• Catnip
• Sunflower
• Garlic
• Peas
• Okra
• Squash
• Carrot
• Zucchini
• Celery
• Brussels Sprouts

The use of seafood including fish and other creatures (crabs, prawns, etc.) by human beings is in practice for a long time. However, the disastrous consequences of this activity are influencing the world. Inclusion of these organisms in the list of natural resources should therefore, be a matter of debate. It has been proved that fishing disrupts the ecological balance and also affects the fish habitat adversely. Similarly, feeding on terrestrial animals (meat) also has affected the food web to a great extent. Enlisting the names of these creatures as 'resources' might spark a debate in a world where we are increasingly becoming aware of problems associated with the fragile ecosystem.

A recent U.N. report studying atmospheric brown clouds finds that they are the newest, and perhaps the worst, threat to the world environment.
The U.N. warned the world again yesterday about the presence of "atmospheric brown clouds," huge plumes of dense smog that are apparently caused by the burning of fuels, including fossil fuels and wood. A U.N. Environment Program report indicates that when mixed with carbon dioxide emissions and other gases, they pose a lethal threat to the world environment. According to Achim Steiner, head of the U.N. Environment Program, "All of this points to an even greater and urgent need to look at emissions across the planet."

The large clouds first became prominent in the world’s consciousness during the Summer Olympic Games that were held in Beijing last summer and are said by scientists to be especially thick around glaciers in the Himalaya and Hindu Kush mountain ranges. Scientists warn that not only could the clouds lead to further global warming, but could also contribute to extreme weather conditions that have seemed to occur more frequently in recent years. On top of that, it is also widely believed that the changes to the environment expected to be wrought by the clouds will have "negative effects on water resources and crop yields," according to the U.N. report.

Yet another concern surrounding the insidious clouds is that they will cause human health problems, including those often associated with so-called "particulate pollution," particularly cardiovascular and respiratory diseases. Some cities in particular appear to be bearing the brunt of the massive levels of fossil fuels being burned in Central and Far East Asia, including Bangkok, Beijing, Cairo, Dhaka, Karachi, Kolkata, Lagos, Mumbai, New Delhi, Seoul, Shanghai, Shenzhen and Tehran. The clouds were also cited as the source of light loss in cities such as Karachi, New Delhi, Shanghai and Beijing.

While the recent study focused primarily on the brown clouds and their formation and effects on Asia, it has been found that the clouds also form in other parts of the world and can move across entire continents in a matter of just three to four days. The clouds do form in the eastern United States and in Europe, but the heavier amounts of snow and rain in those regions tend to lessen the effect.

Here is an account of the adverse air pollution effects, and what you can do to protect yourself against it.

Here are a few reports that have come out recently about the adverse effects of air pollution which will make you sit up and sniff the air around you apprehensively:
According to a study, living in a major city places people at a higher risk than living in the radioactive zone in Chernobyl.
According to the World Health Organization (WHO), about 2 million premature deaths are caused each year due to air pollution in cities across the world.
A recent study has revealed that exposure to fine particle matter in polluted air increases the risk of hospitalization due to respiratory and cardiovascular diseases.
According to a German study, people who breathe in the fumes of heavy traffic regularly have higher chances of getting hardening of the arteries, which is associated with the risk of heart attack.
A Scottish study has shown that jogging with traffic around results in reduced blood flow to the heart. This is particularly dangerous for people with stable heart disease, because it can trigger off cardiac arrhythmia or even a heart attack.
According to a study conducted on eight-year-olds in Mexico City, being exposed for a long time to high levels of polluted air reduces lung function and growth in children.
According to a 20-year study conducted on the residents of Los Angeles, it has been shown that the adverse effects of air pollution have been grossly underestimated. The researchers opine that chronic health problems due to particulate matter in the air may be double or even triple times greater than the estimates available currently.
So what is air pollution and why is it so harmful? Air pollution is caused when it gets filled with too much gases, particulate matter, and droplets of liquid. In cities, the air gets polluted by the exhaust fumes of vehicles, along with the pollutants given off by construction work and industry. In the country, the dust given off by tractors working on fields, vehicles being driven on gravel or dirt tracks, smoke given off by crop and wood being burnt, and work carried out in rock quarries, are some of the causes of air pollution.

Another major air pollutant in cities is ozone that occurs at ground level. Ozone forms when nitrous oxides and hydrocarbons react with sunlight. However, not everything about ozone is bad. In fact, its presence in the upper atmosphere is beneficial because it keeps out harmful ultra-violet rays, which is one of the major causes of skin cancer. Ozone only becomes problematic when it occurs near the ground where it can be inhaled. When inhaled, ozone causes reduced lung capacity, choking, and coughing.

When the air is polluted, it causes irritation of the throat, lungs and eyes. Some of the common symptoms are: a burning sensation in the eyes, tightness in the chest, and coughing. It exacerbates respiratory conditions like emphysema and asthma, and reduces the body’s capacity to fight off infections of the respiratory system. Also, people afflicted with heart disease, like angina, are usually very sensitive to air pollution. People who exercise outdoors are also susceptible to the symptoms of air pollution, because it involves deeper and faster breathing.

In fact, polluted air is particularly detrimental to those who have lung and/or heart disease. When the pollution levels become very high, it can lead to them having to curtail their activities and even result in hospitalization. Severe air pollution has even been known to cause death in the recent past. However, such high levels of pollution are now not as common in the US.

Another group that is susceptible to the effects of air pollution is children. When they live in areas that have high levels of pollution, children tend to be prone to illnesses like earaches and bronchitis.

Although some groups of people feel the effects of air pollution more acutely, one of the positive factors is that when there is an improvement in the quality of air, the symptoms caused by air pollution are quickly alleviated for most people who are healthy.

The long-term effects of being exposed to low air pollution levels are still being studied.

Here are some of the ways you can prevent the harmful effects of air pollution affecting you and your family:
Try staying indoors as much as possible in the daytime. Usually the air indoors is less polluted than outdoors.
If you cannot avoid going outside, try to do it in the early morning or after sunset. This is particularly important when there are high levels of ozone, which is usually the case in many big cities, because sunshine triggers off the creation of ozone.
When the pollution levels are high, try not to exert yourself. The harder you breathe, the more polluted air you inhale into your lungs.
The above steps should be enough to protect you against air pollution if you are healthy. However, in case you work or live near some source of pollution, or if you are afflicted with chronic lung or heart problem, it is best to seek medical advice on the best ways to deal with it.

Air pollution is a major cause for concern these days with increasing awareness of its harmful effects on the environment. Here is a discussion about it as well as a few air pollution control systems.

Air pollution is caused by gases and particles, both liquid and solid, which contaminate the environment. Scientists link this kind of contamination of the air to adverse health effects such as respiratory diseases and even cancer. Some of the other harmful effects of air pollution are: damage to heritage buildings and artifacts, for example, due to air pollution in the city of Athens there is evidence of corrosion on the marble statues of the Parthenon; damage to agricultural products causing reduction in the growth of trees and crop yields; reduction in visibility in the atmosphere; and change in the climate, since particulate pollutants are absorbed by the gases in the atmosphere, resulting in global warming.

The Various Sources of Air Pollution

Some of the anthropogenic sources of air pollution are:
Power plants that are combustion fired
Controlled practices of burning carried out in forestry and agricultural management
Air pollution emissions generated by motorized vehicles; marine vessels like cruise ships and container ships; and airplanes
Air pollution created by incinerators, furnaces, stoves, fireplaces, and burning wood
General industrial activity, power plants, and oil refineries
Burning of crop waste in farming, and chemicals
Fumes from aerosol sprays, varnish, hair spray, paint, and other solvents
Waste deposits in landfills, which give off methane
Some of the natural sources of air pollution are:
Dust that is blown in large areas that have very little vegetation
Methane given off by cattle due to digestion of food
The radioactive gaseous element, radon, formed by radioactive decay that occurs in the Earth's crust
Carbon monoxide and smoke from wildfires
Volcanic eruptions, which produce ash particles, chlorine, and sulfur
Air Pollution is an International Problem

The trouble with air pollution and the problems caused by it is that it often does not remain confined to any geographical region. For instance, the radioactive cloud that resulted from the nuclear accident in Chernobyl, in 1986, spread as far as Ireland. According to a report by the United Nations, Southeast Asia is covered by a two-mile thick haze, called the Asian browncloud, which has been created by the burning of fossil fuels and wood. This haze could be responsible for thousands of death in the region due to respiratory problems.

Efforts to Reduce Air Pollution

These days there are many technologies available that can be used to control air pollution, which go hand-in-hand with strategies in urban planning that are designed to reduce air pollution. For example, there is debate ongoing worldwide about how to reduce the dependence we have on fossil fuels for our energy requirements and shift instead to using environmentally friendly renewable sources of energy. Regulations are already in place to use air pollution control systems at industrial plants, power plants, oil refineries, and so on.

Air Pollution Control Equipment

Here are a few air pollution control systems that are being used by vehicles and industries. They help to either remove pollutants from a stream of exhaust before they are emitted into the air or destroy them.

Air Pollution Control Systems To Reduce Particulate Matter

Wet Scrubbers: These include a number of devices that remove pollutants from furnace flue gas as well as other gas streams. The pollutants are removed by the polluted gas stream being forced through a scrubbing liquid or by using some other method of bringing it into contact with the liquid. Wet scrubbers are used in a number of industries like large power plants, asphalt plants, steel plants, fertilizer plants, and acid plants.

Electrostatic Precipitator (ESP): Also known as Electrostatic Air Cleaners, this air pollution control system is a particulate collecting device which uses the force created by an induced electrostatic charge to remove particulate matter from any flowing gas, e.g. air. These filtration devices are highly efficient and are very effective in removing fine particles like smoke and dust from the air stream. ESPs are used for controlling particulate emissions in various industries like oil refineries, pulp mills, and oil and coal fired utilities that generate electricity which produce smoke.

Dust Cyclones: These are used to remove particulate matter from a gas or air stream, without using filters, using vortex separation instead. Mixtures of fluids and solids are separated by using gravity and rotational effects. There is large-scale use of cyclones in oil refineries as well as the cement industry wherein they form a part of the kiln preheaters.

Air Pollution Control Systems To Reduce NOx (Nitrogen Dioxide and Nitrogen Oxide)

Exhaust Gas Recirculation (EGR): This is a technique used for reducing NOx that is used in most diesel and gasoline engines. A part of the exhaust of an engine is recirculated back into its cylinders. When the incoming air is intermixed with the recirculated exhaust gas, it results in diluting the mixture with inert gas, reducing the adiabatic flame temperature and also lowering the excessive oxygen in diesel engines. The peak combustion temperature is also lowered because the specific heat capacity of the mix is increased by the exhaust gas. Since high temperatures cause Nox to form much faster, EGR helps in limiting NOx from being generated. Nox is produced when a mixture of oxygen and nitrogen is subjected to high temperatures.

Catalytic Converter: This is a device that is used to diminish the toxicity of emissions that are produced by internal combustion engines. First introduced in 1975 in the US in order to comply with the tightening regulations by the Environmental Protection Agency, catalytic converters are still used most commonly in the exhaust systems of motor vehicles. Some of the other places they are use in are: trains, mining equipment, forklifts, generator sets, and other machines equipped with engines.

Air Pollution Control Systems To Decrease Volatile Organic Compounds (VOC):

Gas Flare: Also called a flare stack, this is a chimney that is erected on oil rigs or oil wells, as well as landfills, chemical plants, and refineries. When flammable gas or unusable waste gas plus liquids are discharged by pressure relief valves, this device is used to burn them off. This device is also used in landfills to burn and/or vent the waste gas that is produced by the decomposing materials.

Biofilters: This is a technique for pollution control which uses living matter to trap and biologically degrade pollutants. In air pollution control, the pollutants in the air are subjected to micro biotic oxidation. In other words, when it is applied in the filtration and purification of air, microorganisms, such as fungi and bacteria that are embedded in a biofilm, are used to degrade the air pollutant.