XU Youxia, ZHOU Xu, ZHAO Juan, et al. Vegetation Coverage Variation Features River in Semi-humid and Semi-dry Transitional Region of Taohe River Basin[J]. Bulletin of Soiland Water Conservation, 2016, 36(6): 308-314.
DOI:
XU Youxia, ZHOU Xu, ZHAO Juan, et al. Vegetation Coverage Variation Features River in Semi-humid and Semi-dry Transitional Region of Taohe River Basin[J]. Bulletin of Soiland Water Conservation, 2016, 36(6): 308-314. DOI: 10.13961/j.cnki.stbctb.2016.06.052.
Vegetation Coverage Variation Features River in Semi-humid and Semi-dry Transitional Region of Taohe River Basin
[Objective] The objective of this paper was to analyze the variation of vegetation coveragein in semi-humid and semi-dry transitional region of Taohe River basin through high resolution RS image in order to provide a reference for the implementation of new way of returning farmland to forest and grassland
and for decision making of the basin's ecological civilization construction and sustainable development.[Methods] Landsat 5TM in 1993
Landsat 7ETM+ in 2000
Landsat 8 OLI in 2015 and ASTER GDEM data sets were used in this paper. Firstly
Dimidiate Pixel Model was used to invert vegetation coverage. Then base units extracted from the basin partition
elevation
slope and aspect were used to count and analyze the mean and variation area ratio of vegetation coverage.[Results] On a whole level
vegetation coverage mean increased by 17.52% in Taohe River basin from 1993 to 2015. Increased area covered 62.24% and the decreased covered 6.41%. The date sets showed that the lowest vegetation coverage was below the altitude of 2 000 m. The sum area ratio of decrease and no significant change run up to the maximum as the altitude is above 4 000 m. Vegetation coverage reached the lowest but increased fast in the slopes between 0°~5° and 10°~15°. The sum area ratio of decrease and no significant change grew with the increase of slope
and reached its highest as it was above 60° (covered 67.48%). Effect of slope exposure to the the distribution of the vegetation coverage was weaken.[Conclusion] The results showed that the basin's general trend of vegetation coverage was increasing
but there were still decrease in some areas and had significant variation features. In the future we should pay great attention to vegetation restoration in the areas as the elevation is below 2 500 m
slope grade is below 20° and the slope aspect is western
southern or at level ground. Existing vegetation should be well protected in the elevation above 4 000 m
and when slope is above 45° and slope aspect is eastern and northeast.