国内外灌木生物量模型研究综述

灌木林是自然界中广泛存在的一种陆地生态系统类型, 是森林资源的重要组成部分。文中对国内外灌木生物量模型的研究现状进行了综述, 从数据采集、建模方法和模型评价3个方面系统总结了灌木生物量模型研建的技术要点。数据采集主要包括样本单元数的确定、测定因子的选定和样本数据采集3部分, 其中样本数据采集又包括野外鲜质量测定和实验室干质量测定2部分。建模方法的重点是确定灌木生物量模型的结构和选择参数估计方法, 而模型评价的核心是选定合适的评价指标。文中从开展国家级森林植被生物量监测的角度提出建立灌木生物量模型的有关建议, 即首先要确定合理的建模样本单元数, 再选择合适的灌木生物量建模技术方法, 还要重视对所建模型的评价, 给出模型的预估精度指标。

A Review of Studies of Shrub Biomass Modeling

Shrubs, a type of terrestrial ecosystems widely existing in nature, are the important component of forest resources. The paper reviewed the research of shrub biomass modeling at home and abroad, and summarized systematically the key technical aspects of shrub biomass modeling, including data collection, modeling procedure, and model evaluation. Data collection involves three aspects: determination of sample number, selection of measurement variables, and sample data collection which includes fresh weight mensuration in field and dry weight measurement in laboratory. Modeling procedure puts stress on determining the structure of shrub biomass models and selecting the method of parameter estimation. Model evaluation puts the focus on choosing appropriate evaluation indicators. Finally, some suggestions on modeling shrub biomass equations were suggested, with the consideration on the need of implementing national forest biomass monitoring, i.e., determining a reasonable sample number, selecting the appropriate modeling approach, and laying special stress on model evaluation, especially providing the prediction precision index such as mean prediction error.