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林分胸徑和樹高關(guān)系評(píng)價(jià)全國(guó)針葉樹種立地質(zhì)量的適用性

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中圖分類號(hào):S757.2 文獻(xiàn)標(biāo)志碼:A 文章編號(hào):1001-411X(2025)03-0370-09

Applicability of the relationship between stand DBH and height to evaluate the site quality of major coniferous stands in China

WUHeng12, TIAN Xianglin3,LUO Chunlin1 (1 SouthwestSurveyandPlanningIstitute,NationalForestryandGrassandAdministration,Kunming 65o1,hina; 2 Department Sciences, University of Helsinki, Helsinki FI Ooo14, Finland; 3 College of Forestry, Northwest A & F University, Yangling 712100, China)

Abstract: 【Objective】 To establish a scientific site quality evaluation system, guide forestry production practice. 【Method】 Based on the number of major coniferous forest stand plots across the country, 16 coniferous tree groups were clasified. The Richards, Logistic,and Korf models were applied to fit the guiding curves and establish a site form index model, which was then validated through a scater plottest.Data from four consecutive forest inventory periods from 1999 to 2018 were used to analyze dynamic changes in site form levels. 【Result】 The mean coefficients of determination for guiding curves fited with the Richards, Logistic, and Korf models were all above O.95. The scatter plot validation of the established site form index model showed test values exceeding 9 0 . 0 0 % , with an average value of 9 6 . 5 9 % , indicating its feasibility forpractical use. Over 2O years,site quality for coniferous stands improved, with a combined proportion increase of 7.60 percent in grades I and II,a 3.50 percent decrease in grade II,and a combined reduction of 4.10 percent in grades IV and V. 【Conclusion】 Developing a national unified site quality assessment model based on DBHheightrelationships is feasible and reasonable.This approach reduces the impact deviations of climate-induced and age-based growth rate on site quality assessment, allowing for comparable site quality evaluations across regions.The model demonstrates good applicability ona large scale,though it is essential to consider potential uncertainties due to management practices and limited sample data.

Key words: Site quality; DBH-height; Dynamic change; Coniferous forest stand

立地質(zhì)量是影響林分生長(zhǎng)的關(guān)鍵因素,準(zhǔn)確評(píng)價(jià)立地質(zhì)量是科學(xué)經(jīng)營(yíng)森林的前提和基礎(chǔ)[1-2]。(剩余9165字)

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