Vegetation damage

When the steam was shut off and, 15 minutes later, the agitator was switched off, heat transferred from the hot wall above the liquid level to the top part of the liquid, which became hot enough for a runaway reaction to start. This resulted in a release of TCDD (dioxin), which killed a number of nearby animals, caused dermatitis (chloracne) in about 250 people, damaged vegetation near the site, and required the evacuation of about 600 people (Kletz 1994). 

The agricultural and forest products industries are dependent on renewable resources for their existence. They are also acutely aware that air pollution can damage vegetation and, therefore, threaten their existence. Both industries have been exempt from many air pollution regulations in the past, but now they are finding these exemptions questioned and in some cases withdrawn (15). 

Smog reduces visibility, irritates the eyes, and damages vegetation. This smog was photographed over New York City. 

Most ultraviolet radiation is blocked by Earth s atmosphere, but some solar ultraviolet radiation penetrates the ozone and aids in plant photosynthesis and the production of vitamin D in humans. Too much ultraviolet radiation can burn the skin, cause skin cancer and cataracts, and damage vegetation. 

Liu H., Xiao D. 2008. A novel low-damage vegetable gum-based fracturing fluid and its application in low-permeability reservoirs. Acta Petrolei Sin. 2008-06. 

Ozone protects the Earth by absorbing harmful electromagnetic rays emanating from the Sim. Without the ozone these rays can reach the earth and damage vegetation and can cause skin cancer in people. This is particularly a problem when fair-skiimed non-indigenous people move into a country that receives high levels of solar radiation, such as Australia. 

FIGURE 7.15 The leaf of a lemon tree afflicted with chlorotic stippling because of exposure to oxidants in a smoggy atmosphere. This condition, which can seriously damage vegetation, is characterized by bleached or yellow spots on the leaves. 

Receptors. The receptor can be a person, animal, plant, material, or ecosystem. The criteria and hazardous air pollutants were so designated because, at sufficient concentrations, they can cause adverse health effects to human receptors. Some of the criteria pollutants also cause damage to plant receptors. An Air QuaUty Criteria Document (12) exists for each criteria pollutant and these documents summarize the most current Hterature concerning the effects of criteria pollutants on human health, animals, vegetation, and materials. The receptors which have generated much concern regarding acid deposition are certain aquatic and forest ecosystems, and there is also some concern that acid deposition adversely affects some materials. 

Green coloration, present in many vegetable oils, poses a particular problem in oil extracted from immature or damaged soybeans. Chlorophyll is the compound responsible for this defect. StmcturaHy, chlorophyll is composed of a porphyrin ring system, in which magnesium is the central metal atom, and a phytol side chain which imparts a hydrophobic character to the stmcture. Conventional bleaching clays are not as effective for removal of chlorophylls as for red pigments, and specialized acid-activated adsorbents or carbon are required. 

Produce. Eresh fmits and vegetables must be handled gendy because of sensitive stmctures and the ubiquitous presence of microorganisms. Damage to the product surfaces provide channels through which microorganisms can enter to initiate spoilage. 

Sulfur dioxide Fuel combustion (coal, oil), smelting and casting, manufacture of paper by sulfite process Primary metals (ferrous and nonferrous) pulp and paper Sensory and respiratory irritation, vegetation damage, corrosion, possible adverse effect on health... 

Hour Diurnal cycle Sequenhal sampler Vegetation damage... 

Just as it costs money to control pollution, it also costs the public money not to control pollution. All the adverse Air Pollution Effects represent economic burdens on the public for which an attempt can be made to assign dollar values, i.e., the cost to the public of damage to vegetation, materials. 

The movement of fluoride through the atmosphere and into a food chain illustrates an air-water interaction at the local scale (<100 km) (3). Industrial sources of fluoride include phosphate fertilizer, aluminum, and glass manufacturing plants. Domestic livestock in the vicinity of substantial fluoride sources are exposed to fluoride by ingestion of forage crops. Fluoride released into the air by industry is deposited and accumulated in vegetation. Its concentration is sufficient to cause damage to the teeth and bone structure of the animals that consume the crops. 

Injury to plants and vegetation is caused by a variety of factors, of which air pollution is only one. Drought, too much water, heat and cold, hail, insects, animals, disease, and poor soil conditions are some of the other causes of plant injury and possible plant damage (3). Estimates suggest that less than 5% of total crop losses are related to air pollution. Air pollution has a much greater impact on some geographic areas and crops than others. Crop failure can be caused by fumigation from a local air pollution source or by more widespread and more frequent exposure to adverse levels of pollution. 

Heavy metals on or in vegetation and water have been and continue to be toxic to animals and fish. Arsenic and lead from smelters, molybdenum from steel plants, and mercury from chlorine-caustic plants are major offenders. Poisoning of aquatic life by mercury is relatively new, whereas the toxic effects of the other metals have been largely eliminated by proper control of industrial emissions. Gaseous (and particulate) fluorides have caused injury and damage to a wide variety of animals—domestic and wild—as well as to fish. Accidental effects resulting from insecticides and nerve gas have been reported. 

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