A Model for Estimating Total Forest Coverage with Ground-Based Digital Photography  

作　　者：GU Zhu-Jun ZENG Zhi-Yuan SHI Xue-Zheng LI Lin D. C. WEINDORF ZHA Yong YU Dong-Sheng LIU YongoMei 

机构地区：[1]State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences,Nanjing 210008 (China) [2]School of Bio-Chemical and Environmental Engineering, Nanjing Xiaozhuang University, Nanjing 211171 (China) [3]College of Geography Science, Nanjing Normal University, Nanjing 210097 (China) [4]Department of Earth Sciences, Indiana University-Purdue University, Indianapolis, IN 46202 (USA) [5]LSU AgCenter, Baton Rouge, LA 70803 (USA)

出　　处：《Pedosphere》2010年第3期318-325,共8页土壤圈（英文版）

基　　金：Supported by the National Basic Research Program (973 Program) of China (No.2007CB407206);the National Natural Science Foundation of China (No.40371053)

摘　　要：Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurement-based 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 × 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.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 × 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.

关 键 词：digital camera 2-layer photography shrub-grasses trees 

分 类 号：S757.2[农业科学—森林经理学] TP393[农业科学—林学]