I found interesting issues from AGU (American Geophysics Union) bulletin. A research spotlight on how the swing of axe will affect the atmospheric condition - particularly its chemistry.
From Journal of Geophysical Research - Atmospheres, doi:10.1029/2010JD14021, 2010When a tree is cut down, carbon that has been stored for tens, hundreds, or even thousands years is released to the environment. In addition, feeling that tree slightly alters the wind's path through the woods. If enough forest is cleared, significant changes can be seen in the weather patterns and the global carbon cycle.However, the forest is more than a box of carbon and wind screen. In a news study,Ganzeveld et al. used a climate model that takes into account atmospheric chemistry and gas exchanges at the Earth's surface. The researches wanted to understand the long-term effect of land use change, which, in addition to carbon cycle and weather pattern effects, can also affect concentrations of various reactive trace gases in the atmosphere, including greenhouse gases such as methane and ozone. Using a land cover and land use projection for the year 2050, the authors find that Earth should expect higher concentrations of ground-level ozone and an increase in the oxidizing capacity of the atmosphere. As deforestation continues, the amount of the turbulence in the lower atmosphere will decrease, reducing mixing and leading to buildup of ground-level zone.An example of deforestation in Borneo, Indonesia. Given current deforestation rates, theAssessment estimates that 98 percent of Indonesia's forest may be destroyed by 2022. Leading drivers of forest loss include illegal logging, oil palm plantations, and forest fires (source : http://earthtrends.wri.org)The researches emphasize the dynamic impacts of land use change on the various gases, something they say is not usually taken into account in climate models. For instance, forest soils are a larger source of nitric oxide emmisions than croplands. However, agricultural practices like fertilizer use more than ofset offset the differences in the exchange of nitric oxide between the soil and the sky (nitric oxide is converted in air to dark brown nitrogen dioxide, a major component of smog). Because of these and a number of other competing forces, the authors predict a net increase in nitric oxide emissions by the year 2050. The importance of these dynamic interactions suggests that human practices and land use strategies could have far-reaching and complex effects.Deforestation, seen in the bald patches above, affects not only the carbon cycle but also ozone and nitrogen concentrations in the atmospehere
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