Validation of satellite-derived forest metrics in northeastern China

Over the past two decades, national reforestation efforts and anthropogenic pressures have altered the landscape of northeastern China. In an effort to develop an operational forest monitoring system for the expansive northeastern China region, the accuracy of satellite-derived forest metric information has been evaluated. An area within Heilongjiang province served as the study site. This region, which spans portions of both the Tahe and Mohe Bureaus of Forestry, lost over 1 million hectares of forest during a large forest fire in May/June of 1987. One year after the conflagration, a ten-year reforestation effort commenced. Using Landsat data spanning 1986 to 2002, the photosynthetic recovery of the forest vegetation has been documented. Subsequently, Landsat 7 ETM+ data have been used to establish forest metric correlations. To quantify forest metrics, correlations between Landsat spectral information and in situ measurements (species composition, age, average diameter at breast height (dbh), crown closure, height, and timber volume), as surveyed by the local Forest Management Bureau in 1999/2000, were developed. Preliminary results indicate that age, dbh, and average stand height are well correlated to spectral data and can be used to develop predictive models, while timber volume shows little to no relationship. Hereafter, these methodologies and correlations will be extended both spatially and temporally to provide a regional assessment of carbon sequestration.