【摘 要】
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Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurementbased model was developed to derive total
【机 构】
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State Key Laboratory of Soil and Sustainable Agriculture,School of Bio-Chemical and Environmental En
论文部分内容阅读
Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurementbased model was developed to derive total forest VFC (TG) as well as the VFC of trees (T) and shrub-grasses (G) separately in a subtropical forest area in Nanjing, China. Both upward and downward photographs were taken with a digital camera in 72 quadrats (10 m x 10 m each). Fifteen models were established and validated. Models jointly using both T and G performed better than those using the T and G separately. The best model, TG = T + G - 1.134 × T × G - 0.025(R2 = 0.9115, P < 0.01, root mean squared error = 0.0789), is recommended for application. This model provides a good way to obtain total forest VFC values through taking tree and shrub-grass photos on ground below tree canopy rather than above tree canopy.
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