Air Pollution And How It Affects Plants — страница 2

  • Просмотров 274
  • Скачиваний 12
  • Размер файла 17

Increasing water temperature also makes aquatic plants and animals grow faster. It also speeds up the use of food, rate of gas exchange and heartbeat in animals. The organisms grow faster, but do not grow as large or live as long as normally in cooler water. Many aquatic animals will not reproduce if the temperature is raised even a few degrees. Studies show that water temperature above 30.C decreases the number of diatoms and increases the number of blue-green algae. Besides the blue-green algae producing an unpleasant odor and unpleasant taste, they seem not to be a good source of food for algae-eating organisms. This type of pollution; dumping hot water into streams, lakes or rivers is called thermal pollution. The other categories also have bad effects on aquatic life.

Excessive sedment will reduce the amount of sunlight hitting the water and will affect the photosynthesis in green aquatic plants. These plants are necessary for oxygen production which help maintain a normal balance in the water. Many of these green plants are a necessary food source for the animal life found in the water body. Radioactive substances can accumulate in living organisms, aquatic life as well as in humans when the exposure is sufficiently severe. Synthetic organic chemicals include detergents and cleaning agents used in homes, synthetic organic pesticides and the residue from synthetic chemicals used during industrial processes. These chemicals are toxic to fish and other aquatic life and cause serious taste and odor problems. Inorganic substances include many of

acids, metal salts, solId matter and various other chemical compounds. These materials include ammonia, arsenic, barium, boron, cadmium, chloride, chromium, copper, fluoride, iron, lead, manganese, nitrates, nitrites, phosphorus, selenium, silver, sulfates and zinc. Pollution by these substances is a result of oil field activities, mining processes, manufacturing processes and agriculture. Plants are the way the sun s energy can be used by all animals. The plants provide oxygen in the air we breathe. Plant life is much more sensitive to air pollution than animal life. Many times plants are used to gather new data about air contaminants because they are sensitive. The pollutants that harm plants are sulfur dioxide, hydrogen fluoride, and ethylene. Some plant damage is caused by

the contaminants in photochemical smog and by ozone. Air pollution determines where come vegetable crops can be raised. Every urban area in the United States has vegetative damage from air pollution, especially in New Jersey, California and parts of Florida. Substances that come from combustion react with sunlight and moisture to form the oxidant called PAN, is the cause of death of plants and trees along California highways. PAN is toxic to many forms of farm produce. Damage to vegetation as a result of air contaminants is so bad that commercial and non-commercial production of crops and forests in many areas has been jeopardized and in some areas discontinued. Human s are also effected by air pollution. There are three major diseases related to air pollution. The first is

asthma, an asthma attack is when a persons bronehioles narrow. This is caused by a muscle spasm, and enlargement of a persons mucous membrane causing increased mucous secretions. Bronchits and Emphysema are also caused by air pollution. These two diseases occur ethier simultanously or emphysema may be followed-up by bronchitis. When you have emphysema your aveoli become enlarged and eventually break down or burst. Both bronchitis and emphysema include shortness in breath. In advance cases people are unable to blow out a lit match only a few inches from their mouth. Cancer is also caused by air pollution. Cancer is an uncontrolled cell growth. Lung cancer is the abnormal and uncontrolled growth of cells which usually starts in the bronchial mucous membranes. The main reason for

controlling pollution is to protect human health and the balance of human s life-support systems. Other benefits can result from clean-up measures for example, financial savings and more efficient productivity. All arguments against pollution controls are silenced with the money factor. We cannot afford clean air: it costs too much. Electric utility spokespersons say that the cost of adequate filtration of smokestacks is too much. They claim the public won t stand for the additional cost of electricity. Still, we pay regular increases on our utility bills, for whatever reasons. The auto makers argue that the car-buying public won t accept the cost of too many emission control devices on new car prices. Still, we pay time and time again for yearly model changes and practicaly