Modeling Compatible Single-Tree Aboveground Biomass Equations of Masson Pine (Pinus massoniana) in South China

Wei Sheng Zeng,Shou Zheng Tang

doi:10.1038/npre.2012.6754.1

Abstract

AbstractIn the background of facing up to the global climate change, it is becoming the inevitable demand to add forest biomass estimation to national forest resource monitoring. The biomass equations to be developed for forest biomass estimation should be compatible with volume equations. Based on the tree volume and aboveground biomass data of Masson pine (Pinus Massoniana Lamb.) in south China, the one, two and three-variable aboveground biomass equations and biomass conversion functions compatible with tree volume equations were constructed using the error-in-variable simultaneous equations in this paper. The results showed: (i) the prediction precision of aboveground biomass estimates from one variable equation was more than 95%; (ii) the regressions of aboveground biomass equations improved slightly when tree height and crown width were used together with diameter on breast height, although the contributions to regressions were statistically significant; (iii) for biomass conversion function on one variable, the conversion factor was decreased with growing diameter, but for conversion function on two variables, the factor was increased with growing diameter while decreased with growing tree height.

Highlights

Since forest ecosystems play irreplaceable roles in regulating global carbon balance and mitigating global climate change, the forest biomass monitoring is becoming more important all over the world
The national monitoring for forest volume deriving from tree volume equations have been conducted for several decades, but the national monitoring for forest biomass deriving from tree biomass equations have been implemented for recent years, and even have not been taken in many countries including China (Tomppo et al, 2010)
4.1 Compatible biomass equations Using the tree volume and aboveground biomass data of 150 sample trees for Masson pine in south China, nonlinear error-in-variable simultaneous equations based on one, two and three variables were fitted through ForStat2.1, and applying the parameter estimates to compute the statistics from expressions (7)~(9)

Summary

Introduction

Since forest ecosystems play irreplaceable roles in regulating global carbon balance and mitigating global climate change, the forest biomass monitoring is becoming more important all over the world. For implementing the monitoring and assessment of national forest biomass, it is becoming the inevitable demand to develop generalized single-tree biomass models suitable for large scale forest biomass estimation. The stem biomass, which is equal to stem volume multiplying wood density, contributes about 70% of total aboveground biomass of individual tree. The national monitoring for forest volume deriving from tree volume equations have been conducted for several decades, but the national monitoring for forest biomass deriving from tree biomass equations have been implemented for recent years, and even have not been taken in many countries including China (Tomppo et al, 2010). Considering the high relationship between biomass and volume, the biomass equations should be compatible with volume equations when forest biomass was added to national forest resources monitoring

Methods

Results

Conclusion