Soil is the main predictor of secondary rain forest estimated aboveground biomass across a neotropical landscape

We studied the relative effects of landscape configuration, environmental variables, forest age and spatial variables on estimated aboveground biomass (AGB) in Costa Rican secondary rain forests patches. We measured trees > 5 cm dbh in 24, 0.25 ha plots and estimated AGB for trees 5-24.9 cm dbh and for trees > 25 cm dbh using two allometric equations based on multispecies models using tree dbh and wood specific gravity. AGB averaged 87.3 Mg/ha for the 24 plots (not including remnant trees) and 123.4 Mg/ha including remnant trees (20 plots). There was no effect of forest age on AGB. Variation partitioning analysis showed that soils, climate, landscape configuration and space together explained 61% of tree AGB variance. When controlling for the effects of the other three variables, only soils remained significant. Soil properties, specifically K and Cu, had the strongest independent effect on AGB (variation partitioning, R2=0.17, p=0.0310), indicating that in this landscape, AGB var...

本研究针对哥斯达黎加次生雨林斑块的地上生物量（aboveground biomass, AGB）估算值，探究了景观格局、环境变量、林龄与空间变量的相对影响效应。研究团队在24块面积为0.25公顷的样地中，对胸径（diameter at breast height, DBH）大于5厘米的林木开展了调查，并基于以林木胸径和木材比重为参数的多物种异速生长方程，分别对胸径5~24.9厘米以及胸径大于25厘米的林木的AGB进行了估算。24块样地的AGB平均值为87.3 Mg/ha（不含遗留林木），包含遗留林木的20块样地AGB平均值为123.4 Mg/ha。林龄对AGB未产生显著影响。变异分割分析结果显示，土壤、气候、景观格局与空间变量共同解释了林木AGB变异的61%。在控制其余三类变量的影响后，仅土壤变量仍表现出显著效应。土壤属性，尤其是钾（K）与铜（Cu）元素，对AGB具有最强的独立影响效应（变异分割分析结果：R²=0.17，p=0.0310），这表明在该研究区域内，AGB的变异……