Land Change In The Environment

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Land-cover is a key and effective variable in the Earth system that is related to most of the human and physical environments. Change in the situation of land-cover is an important variable among the global changes that affect environmental systems (Otukei and Blaschke 2010).
Land-cover changes play a main role in the global carbon cycle, and in the exchange of greenhouse gases between the atmosphere and the earth surface (Loveland and Belward 1997). In general, intense human activities have an increase in construction and farmland and destruction of forests, meadows and other natural resources (Lambin and Geist 2003; Lawrence et al. 2012). Agricultural lands increase the entry of nutrients into the water in the basin and in particular affect
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2005; Hua and Chen 2013). Conversely, afforestation and reforestation remove carbon from the atmosphere. New evidences show changes in land-cover that have human origin during the past 150 years have led to the release of large amounts of carbon into the atmosphere. Although the combustion of fossil fuels is the main source of the release of carbon into the atmosphere, land-cover has still significant share (~20 percent) in the pollution ofthe atmosphere. Increase in the level of greenhouse gases and emission of the heat caused by urbanization have increased the Earth temperature significantly. In addition, temperature change affects the amount of humidity and precipitation, which in turn reduces recovery of forests and pastures (Davin and de Noblet-Ducoudré 2010; Hasler et al. 2009; Snyder et al. 2004). In general, we can say that change in land-cover have positive and negative effects on human health and can have favorable or unfavorable consequences (Hansen and DeFries 2004). For example, the conversion of forests and pastures into…show more content…
Land-cover maps have a set of essential information that should be provided in a clear and reliable manner. Detailed and timely information about land-cover is essential for land change monitoring, management of ecosystems and urban planning. Technological advances, the availability of data in appropriate intervals and high-resolution satellite images have made techniques such as remote sensing and GIS very useful for conducting researches such as the analysis of detection of changes in land-cover and prediction of future scenario (Lambin et al. 2001).
Today the classification of satellite images in general is a common method for extracting information related to land-cover patterns and their changes. Several image classifier techniques have been developed, a recent comprehensive review of which can be found in Lu and Weng (2007) . Selection of appropriate classification methods and appropriate spectral bands is very important for increasing the accuracy and precision of
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