The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM+ images with no cloud cover from July/Au...The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM+ images with no cloud cover from July/August in different years (1990, 1995, 2000 and 2005) were used to analyze the change in various land environmental factors over time. The results show that while mining activity initially had a marked adverse impact on the environment, mine rehabilitation measures have also subsequently played a great role in improving vegetation cover and controlling land desertification and loss of water and soil. The effect of coal mining on vegetation cover is dependent upon the soil type and natural indigenous flora. Results of this investigation imply that mining activity has a greater effect on the vegetation of loess areas than at sandy sites. Although local vegetation coverage was improved by planting in the mining area, the total area of land affected by desertification still in- creased from 26.81% in 1990 when large-scale mine construction was introduced, to 46.79% in 1995. With continuous efforts at rehabilitation, the vegetation cover in the Shendong coal mining area was increasing, and loss of water and soil were effec- tively controlled since 1995. Subsequently, the total area of extreme desertification decreased to 23.24% in 2000 and further to 18.68% in 2005. The total area affected by severe loss of water and soil also decreased since the early 1990's (70.61% in 1990, 71.43% in 1995), to 43.64% in 2000 and 34.93% in 2005, respectively.展开更多
An increase in the extremality of natural processes is a consequence of warming, aridization, and desertification. The authors consider the processes of warming, aridization, and desertification to be the parts of a s...An increase in the extremality of natural processes is a consequence of warming, aridization, and desertification. The authors consider the processes of warming, aridization, and desertification to be the parts of a single system and major destabilizing factors of ecological balance. Destabilization is expressed in the growth of natural processes extremality. Ecosystems of Transbaikalia were once characterized by a different natural contrast and amplitude. Warming, aridization and desertification have led to an increase of environmental regimes tensions. This is demonstrated quantitatively by the root-mean-square difference of atmospheric and soil parameters. Quantitative indicators of aridization are estimated using Walter-Gossen climate charts. Permafrost zone response information to the long-term warming is provided as well.展开更多
Two model polygons in the Central Mongolia are considered for investigation of vegetation dynamics. They are located in rainless climatic zones -- arid and semiarid. For the emphasized polygons plots of the NDVI tempo...Two model polygons in the Central Mongolia are considered for investigation of vegetation dynamics. They are located in rainless climatic zones -- arid and semiarid. For the emphasized polygons plots of the NDVI temporal variation and NDVI maps of its multi-temporal values on the base of Landsat TM imagery are constructed. The full-scale landscape indication of the selected NDVI areas with different values with the step through 0.1 is conducted. This indication is supported by the analysis of vegetation to environmental groups for drought resistance. Almost the entire territory of the emphasized polygons vegetation digression during this period was traced. The analysis of the time variation of NDVI shows a decrease of its values. This indicates a trend xerophytization already sparse vegetation of Gobi. In the semiarid climatic zone a digression vegetation trend is directly related to heavy load on the pastures.展开更多
文摘The influences of coal mining in an arid environment on vegetation coverage, land-use change, desertification, soil and water loss were discussed. A series of available TM/ETM+ images with no cloud cover from July/August in different years (1990, 1995, 2000 and 2005) were used to analyze the change in various land environmental factors over time. The results show that while mining activity initially had a marked adverse impact on the environment, mine rehabilitation measures have also subsequently played a great role in improving vegetation cover and controlling land desertification and loss of water and soil. The effect of coal mining on vegetation cover is dependent upon the soil type and natural indigenous flora. Results of this investigation imply that mining activity has a greater effect on the vegetation of loess areas than at sandy sites. Although local vegetation coverage was improved by planting in the mining area, the total area of land affected by desertification still in- creased from 26.81% in 1990 when large-scale mine construction was introduced, to 46.79% in 1995. With continuous efforts at rehabilitation, the vegetation cover in the Shendong coal mining area was increasing, and loss of water and soil were effec- tively controlled since 1995. Subsequently, the total area of extreme desertification decreased to 23.24% in 2000 and further to 18.68% in 2005. The total area affected by severe loss of water and soil also decreased since the early 1990's (70.61% in 1990, 71.43% in 1995), to 43.64% in 2000 and 34.93% in 2005, respectively.
基金partially supported by the Russian Geographical Society(grant No.13-05-41378)
文摘An increase in the extremality of natural processes is a consequence of warming, aridization, and desertification. The authors consider the processes of warming, aridization, and desertification to be the parts of a single system and major destabilizing factors of ecological balance. Destabilization is expressed in the growth of natural processes extremality. Ecosystems of Transbaikalia were once characterized by a different natural contrast and amplitude. Warming, aridization and desertification have led to an increase of environmental regimes tensions. This is demonstrated quantitatively by the root-mean-square difference of atmospheric and soil parameters. Quantitative indicators of aridization are estimated using Walter-Gossen climate charts. Permafrost zone response information to the long-term warming is provided as well.
基金Russian Foundation for Basic Research(120598066r_sibir_a)
文摘Two model polygons in the Central Mongolia are considered for investigation of vegetation dynamics. They are located in rainless climatic zones -- arid and semiarid. For the emphasized polygons plots of the NDVI temporal variation and NDVI maps of its multi-temporal values on the base of Landsat TM imagery are constructed. The full-scale landscape indication of the selected NDVI areas with different values with the step through 0.1 is conducted. This indication is supported by the analysis of vegetation to environmental groups for drought resistance. Almost the entire territory of the emphasized polygons vegetation digression during this period was traced. The analysis of the time variation of NDVI shows a decrease of its values. This indicates a trend xerophytization already sparse vegetation of Gobi. In the semiarid climatic zone a digression vegetation trend is directly related to heavy load on the pastures.