Implications of Alternative Field-Sampling Designs on Landsat-Based Mapping of Stand Age and Carbon Stocks in Oregon Forests

摘要

The authors compared empirical models relating Landsat reflectance do forest age using two alternate sets of ground data: a large, systematic forest inventory and a smaller set uf plots selected to represent pure conditions along predefined structural grathents. Models built with the smaller set resulted in lower mapping error (RMSE) and higher explanatory power (R2) dian those built with inventory darà. However, some predictions derived from smaller set's models displayed a bias relarive to those built with inventory data. A modeling exercise to translate age into carbon demonstrated how nonlinear ecological models can magnify prediction biases over landscapes. From this study it is clear that, for mapping purposes, inventory data aie superior to project-specific data if those data are not representative of the landscape over which mapping is co be done. [PUBLICATION ABSTRACT]