Volcanoes, pollution from

Most of the sulfur in plants occurs in proteins, especially in the amino acids cysteine and methionine. Other essential compounds that contain sulfur are coenzyme A, a compound essential for cellular respiration and for the synthesis and breakdown of fatty acids, and the vitamins thiamine and biotin. Sulfur can be absorbed by leaves as gaseous sulfur dioxide, S02, an environmental pollutant released from active volcanoes and from the burning of wood or fossil fuels. 

The places from which pollutants emanate are called sources. There are natural as well as anthropogenic sources of the permanent gases considered to be pollutants. These include plant and animal respiration and the decay of what was once living matter. Volcanoes and naturally caused forest fires are other natural sources. The places to which pollutants disappear from the air are called sinks. Sinks include the soil, vegetation, structures, and water bodies, particularly the oceans. The mechanisms whereby pollutants... 

An erupting volcano emits particulate matter. Pollutant gases such as SO2, HiS, and methane are also emitted. The emission from an eruption... 

Hydrogen Sulfide. Hydrogen sulfide is a foul-smelling gas that is released into the atmosphere from volcanoes as well as in the course of decay of animal tissues. As an air pollutant, it reacts with almost all metals, with the exception of gold, forming a dark-colored corrosive layer of metal sulfide, commonly known as tarnish, which discolors the exposed surface of most metals. 

What is clean air Unpolluted air is a concept of what the air would be if humans and their works were not on earth, and if the air were not polluted by natural point sources such as volcanoes and forest fires. The true composition of unpolluted air is unknown because humans have been polluting the air for thousands of years. In addition there are many natural pollutants such as terpenes from plants, smoke from forest fires, and fumes and smoke from volcanoes. Table 4.1 lists the components that, in the absence of such pollution, are thought to constitute clean air. 

Fitzgerald W. F. (1996) Mercury emissions from volcanos. In Abstr. 4th Int. Conf. on Mercury as a Global Pollutant. Hamburg, Germany, August, pp. 4-7. 

World sulfur reserves. The earth s crust contains about 0.6% S, where it occurs as elemental S (brimstone) in deposits associated with gypsum and calcite combined S in metal sulfide ores and mineral sulfates as a contaminant in natural gas and crude oils as pyritic and organic compounds in coal and as organic compounds in tar sands (Tisdale and Nelson, 1966). The elemental form commonly occurs near active or extinct volcanoes, or in association with hot mineral spings. Estimates by Holser and Kaplan (1966) of the terrestrial reservoirs of S suggest that about 50% of crustal S is present in relatively mobile reservoirs such as sea water, evaporites, and sediments. The chief deposits of S in the form of brimstone and pyrites are in Western European countries, particularly in France, Spain, Poland, Japan, Russia, U.S.A., Canada, and Mexico. World production of S in the form of brimstone and pyrites was approximately 41 Tg in 1973 other sources accounted for about 8 Tg, making a total of 49 Tg (Anon, 1973). Byproduct S from sour-gas, fossil fuel combustion, and other sources now accounts for over 50% of S used by western countries, as shown in Fig. 9.1. This percentage may increase as pollution abatement measures increase the removal of SO2 from fossil fuel, particularly in the U.S.A. Atmospheric S, returned to the earth in rainwater, is also a very important source of S for plants. 

The oxides of sulfur create global pollution problems because they have longer lifetimes in the atmosphere than the oxides of nitrogen. Some of the SO2 and SO3 in the air originates from biological processes and from volcanoes, but much comes from the oxidation of sulfur in petroleum and in coal burned for fuel. If the sulfur is not removed from the fuel or the exhaust gas, SO2 enters the atmosphere as a stable but reactive pollutant. Further oxidation by radicals leads to sulfur trioxide ... 

Each country has its own set of requirements for reporting. However, releases from nonpoint sources, although contributing a large share to any industrialized country s pollution burden, are so far included only in a limited number of PRTR systems. These nonpoint, or diffuse, sources include area sources (e.g., residential wood combustion, dry cleaners), mobile sources (e.g., automobiles, aircrafts, trains), biogenic sources (e.g., vegetation and microbial activity), and geogenic sources (e.g., soil erosion and volcanoes). 

Abiotic toxic damage and accumulation of metals and nonmetals in wild and cultivated plants may result from natural geochemical loads in the soil (Kovalskij 1977) caused by macro, trace and ultratrace elements in water used for irrigation, in natural volcanoes and anthropogenic industrial pollution of the atmosphere. Water, aerosols, and dust contain a variety of aluminum, arsenic, cad-... 

Abiotic toxic damages to cultured and wild plants may result from natural geochemical loads in the soil originating from salt or certain trace elements in water, the vicinity of volcanoes, or natural atmospheric pollution. As a rule, however, the cause is anthropo-... 

Sutton, M. A., J. W. Erisman, F. Dentener and D. Moller (2008) Ammonia in the environment From ancient times to the present. Environmental Pollution 156, 583-604 Svehla, G. (1993) Nomenclature of kinetic methods of analysis (lUPAC Recommendations 1993). Pure and Applied Chemistry 65, 2291-2298 Symonds, R. B., W. I. Rose and M. FI. Reed (1988) Contribution of Cl- and F-bearing gases to the atmosphere by volcanoes. Nature 334, 415-418 Symonds, R. B., W. I. Rose, G. Bluth and T. M. Gerlach (1994) Volcanic gas studies methods, results, and applications. In Volatiles in magmas Mineralogical Society of America Reviews in Mineralogy (Eds. M. R. Carroll and J. R. Holloway) pp. 1-66 Szabadvary, F. (1966) History of analytical chemistry. Pergamon, Oxford. 419 pp. 

The global system Earth-atmosphere is the seat of complicated exchange of matter between the stratosphere, the troposphere, the Earth s biosphere, the sea s biosphere and the lithosphere. Uncertainties in much of the data do not allow the global cycle of carbon to be correctly established today. The best known facts concern the atmosphere. The troposphere is fed by pollutants of natural origin resulting from the respiration and oxidation of the biomass, from the oceans (300 Mt NaCl per year) and from volcanoes (10 Mt HCl per year), for example. As sodium chloride and hydrochloric acid are soluble in water they are mainly leached out by the rain and contribute little to... 

A particularly important consequence of the release of gaseous pollutants into the atmosphere is the local acidification of the environment. Rainwater reaching Earth s surface has a pH of about 5.6 (it is lower than 7 because of the dissolved carbon dioxide). In some parts of North America, Europe, and even Asia, however, acidic rainwater of pH < 5.6 is quite widespread. This is believed to be due to the presence of acidic gases, particularly oxides of sulfur (SOjc) and oxides of nitrogen (NO ) in the atmosphere. The contribution of HCl, if any, is relatively minor. A biogenic contribution to acidification caused by emissions from volcanos or forest fires also exists, but is relatively small. 

Nature pollutes the atmosphere to a certain extent — with noxious hydrogen sulfide (H2S) and particulate matter from volcanoes, and the release of... 

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