关键词: 火烧年限, 坡度, 养分循环, 大兴安岭, 化学计量

Abstract: Tree-ring width measurement is the key operation in studies of dendroclimatology, tree growth pattern and forest productivity; its bias magnitude directly affects the final results. Although specialized measurement systems or software are reliable tools for dendrochronology and tree growth analysis, it is inconvenient for labs without such devices. The purpose of this study was to develop a tree ring measuring algorithm which is easy to apply while keeping desired accuracy, especially for labs without the aforementioned conditions. Based on imagery scanned from sample cores, tree ring widths were automatically positioned with an image processor that was commonly used in remote sensing. The extracted widths were corrected with a simple program based on triangle principle for inclined rings. After scanning, the imagery was measured with remote sensing software PCI Geomatica, for which the geocorrection module was used. Results indicated that the final values under the high resolution were highly consistent with instrumentmeasured ones, showing the effectiveness of the method. The method proposed in this paper was simple to operate, convenient for popularization. In addition, it was both time and costeffective, especially when specialized instruments were not available.

Key words: stoichiometry., fire history, slope, Great Xing’an Mountains, nutrient cycle