Deforestation effects

Walsh, J.F. (1993) Deforestation effects on vector-bane disease. Parasitology, 106, 55-75. 

Lettau, H., K. Lettau, and L. Molion. 1979. "Amazonia s hydrologic cycle and the role of atmospheric recycling in assessing deforestation effects." Monthly Weather Review. 107 227-238. 

Land use changes in the tropics have resulted in a landscape characterized as a mosaic of logged forests, cleared fields, and successional forests. This results in the transformation from extremely fire resistant rainforest ecosystems to anthropogenic landscapes in which fire is a common event (16, 17), Fires occur in disturbed tropical forests because deforestation has a dramatic effect on microclimate. Deforestation results in lower relative humidities, increased wind speeds, and increased air temperatures. In addition, deforestation results in increased quantities of biomass that are susceptible to fire. This biomass may be in the form of forest slash, leaf litter, grasses, lianas or herbaceous species (16, 18). 

Reversal of some of the Effects of Deforestation by the Afforestation of Unused Farmland. 

Bala G, Caldeira K, Wickett M, Phillips T, Lobell D, Delires C, Mirin A. Combined climate and carbon-cycle effects of large-scale deforestation. Proceedings of the National Academy of Sciences of the United States of America, 2007.104(16) pp. 6550-6555. doi 10.1073/pnas.0608998104... 

Antibiotic resistance profiles of the bacterial communities reflected the effects of deforestation and the land degradation (Fig. 2). The degradation was significant (p=0.05) as a source of variation for the numbers of soil bacterial cells resistant to lasalocid, penicillin, spectinomycin and trimethoprim, and marginally significant (0.50 Significant differences between two average values were observed for some antibiotics. When compared with the BG soil bacterial community, the DEF soil bacterial community had more bacterial cells resistant to dapson, kanamycin, lasalocid, nafcillin, penicillin, spectinomycin, streptomycin and trimethoprim. 

Detoxification methods, pesticide content of fish, environmental analytical and monitoring techniques. (4 Utilization of biomass, drinking water quality, organic contaminants in lakes and rivers, and effect of deforestation on carbon dioxide and oxygen content of air. 

The carbon cycle has continued in this manner for millions of years. However, scientists have detected an imbalance in the carbon cycle due to the increase in the amount of carbon dioxide produced through burning fossil fuels and the deforestation of large areas of tropical rain forest. The Earth s climate is affected by the levels of carbon dioxide (and water vapour) in the atmosphere. If the amount of carbon dioxide, in particular, builds up in the air, it is thought that the average temperature of the Earth will rise. This effect is known as the greenhouse effect (Figure 13.14). 

The emission of C02 from anthropogenic activities (the combustion of C-based fossil fuels, deforestation, combustion of woods) amounts to approximately 7.5 Gtc per year, or about 3.5% of the total amount cycled in the natural cycle. However, as the natural systems are unable to use such C02, this leads to its accumulation into the atmosphere. The assumption that an increase of the concentration of C02 in the atmosphere would have boosted both the photosynthesis and the dissolution into the oceans has not been proven to be true. In fact, the solubility of C02 is governed by complex equilibria, while photosynthetic fixation is limited by several factors so that, under the increase of the atmospheric concentration from 280 ppm of the preindustrial era to the present-day 380 ppm, there has not been any sensible improvement of the uptake. Therefore, under natural conditions the uptake of C02 has reached an equilibrium state, and the further increase in atmospheric concentrations may more likely cause climate changes through the greenhouse effect and destabilization of the thermal structure of the atmosphere, than improve the elimination of C02 from the atmosphere. 

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