Forests and soils

Johnson D. W., Henderson G. S., and Todd D. E. (1988) Changes in nutrient distribution in forests and soils of walker branch watershed, Tennessee, over an eleven-year period. Biogeochemistry 5, 275-293. 

Subrat, N. (2002). Ayurvedic and herbal products industry an overview. In Workshop on wise practices and experiential learning in the conservation and management of Himalayan medicinal plants. Ministry of Forest and Soil Conservation, Nepal, the WWF-Nepal Program, MAPPA and PPI. Kathmandu, Nepal. 

Pg C/year from deforestation, which is comparable to the 5 Pg released from fossil fuels. Using a global carbon cycle model with a box-diffusion model for the oceans and a simple four-box model for soil and land biota, Peng et al. (1983) make use of the changes in the atmosphere (Fig. 11-21) to deduce the CO2 contribution from forest and soils. The CO2 emissions arrived at for 1980 are about... 

Department of Forest and Soil Sciences, Institute of Soil Science, University of Natural Resources and Applied Life Sciences, Peter Jordan Strasse 82, A-1190 Vienna, Austria... 

Acid precipitation, or ozone as a direct derivative of NO emissions, has been cited as a major cause of acute damage and death to fir and spruce trees found in parts of Bavaria, the Black Forest and Soiling over the last five years. Chronic damage (loss of needles) has also been found quite widely and also necrosis of beach trees More recently, damage attributed to acid precipitation is believed to have occurred in North Rhine Westphalia (Section 6.2). 

Ratter, J.A. et al.. Observations on the vegetation of northeastern Mato Grosso II. Forests and soils of the Rio Suia-Missu area. Proc. R. Soc. Land. 203, 191, 1978. 

The evidence is now massive and convincing that acid rain and related forms of air pollution are taking a serious toll on lakes and streams, forests and soils, water supplies, air quality and human health — a toll that most Americans would find unacceptable. The wide variety of resources affected by acid rain all have one important feature in common, a feature that helps to explain why the problem has been allowed to fester for so long The resources belong to everyone, and therefore to no one. Responsibility for these resources has been diffused so widely that it is virtually non-existent. Furthermore, the effects of acid rain have been cumulative, gradual, and for the most part, un-... 

Trees and soils of forests act as sources of NH3 and oxides of nitrogen. Ammonia is formed in the soil by several types of bacteria and fungi. The volatilization of ammonia and its subsequent release to the atmosphere are dependent on temperature and the pH of the soil. Fertilizers are used as a tool in forest management. The volatilization of applied fertilizers may become a source of ammonia to the atmosphere, especially from the use of urea. 

Consider a lake with a smaU watershed in a forest ecosystem. The forest and vegetation can be considered as an acid concentrator. SO2, NO2, and acid aerosol are deposited on vegetation surfaces during dry periods and rainfalls they are washed to the soil floor by low-pH rainwater. Much of the acidity is neutralized by dissolving and mobilizing minerals in the soil. Aluminum, calcium, magnesium, sodium, and potassium are leached from the soil into surface waters. The ability of soils to tolerate acidic deposition is very dependent on the alkalinity of the soil. The soil structure in the... 

As with other factors, no direct statements can be made relating the reaction of a soil to its corrosive properties. Extremely acid soils (pH 4 0 and lower) can cause rapid corrosion of bare metals of most types. This degree of acidity is not common, being limited to certain-bog soils and soils made acid by large accumulations of acidic plant materials such as needles in a coniferous forest. Most soils range from pH5 0 to pH8 0, and corrosion rates are apt to depend on many other environmental factors rather than soil reaction per se. The 45-year study of underground corrosion conducted by the United States Bureau of Standards included study of the effect of soils of varying pH on different metals, and extensive data were reported. 

Agee, J.K. Prescribed fire effects on physical and hydrologfc properties of mixed conifer forest floor and soil Report 143 Univ. of CA, Water Resources Center Davis, CA, 1973. 

Domenach, A.M., Kurdali, F. and Bardin, R. 1989 Estimation of symbiotic dinitrogen fixation in alder forest by the method based on natural N-abundance. Plant and Soil 118 51-59. 

Tolli J, GM King (2005) Diversity and structure of bacterial chemolithotrophic communities in pine forest and agroecosystem soils. Appl Environ Microbiol 71 8411-8418. 

T. R. Fox and N. B. Comerford, Rhizosphere phosphatase activity and phosphatase hydrolyzable organic phosphorus in two forested Spodosols. Soil Biol. Bioehem. 24 579 (1992). 

R. Fogel, Root turnover and productivity of coniferous forests, Plant Soil 71 75 (1983). 

H Keith, R. J. Raison, and K. L. Jacobson, Allocation of carbon in a mature eucalypt forest and some effects of soil phosphorus availability. Plant Soil 796 81 (1997). 

The low pH of acid precipitation can destroy forests and kill fish. Some lakes and streams lie in soil that has the natural ability to buffer the increased acidity of acid rain, usually because the soil contains a high amount of lime. Other lakes and streams, however, have no such buffering capacity. The pH of the water is not the main problem—at least not directly. The problem lies in the amount of aluminum compounds that are leached out of the soil surrounding the lake or stream at lower pHs. Aluminum is toxic to many aquatic species. 

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