基于优势高模型分析多源数据对立地质量评价的影响

Effects of Multiple Source Data on Site Evaluation Based on Dominant Height Modeling

立地质量的准确评价是森林科学经营的前提,采用不同的数据类型拟合优势树高生长,建立立地指数模型和立地形模型,与其他立地质量评价模型进行对比分析。结果表明,临时或固定样地调查数据建立立地质量评价模型会导致幼龄林高估和成熟林低估,解析木数据无法解释优势木早期受到的压迫和干扰;采用多源数据建立立地质量评价模型能有效降低系统性误差,拟合优势树高生长决定系数从大到小依次是解析木数据、固定样地数据、多源数据和临时样地数据;相较于其他立地质量评价模型,多源数据立地质量评价模型能更准确反映优势树高生长规律,且能有效降低立地质量评价误差;基于多林区不同数据类型建立的立地质量评价模型具有更好的普适性和外推效能。

Accurate evaluation on site quality is the premise for the scientific management of forest stands. In order to establish site index and site form models, different datum sources were employed to fit the dom- inant height growth. The models established were compared with other models that were used for the esti mation of site quality. The models based on temporal and permanent sample plots gave overestimations for young forests and underestimations for mature forests. The guide curve estimated by stem analysis data was unable to explain the competition pressure at the young age. Considering the systematic error,multiple source data were used to constructed site evaluation models, to reveal the trends of dominant height growth. Extrapolation of these models was also validated.