TITLE:
Estimation of Tree Biomass, Carbon Stocks, and Error Propagation in Mecrusse Woodlands
AUTHORS:
Tarquinio Mateus Magalhães, Thomas Seifert
KEYWORDS:
Aboveground Production, Additivity, Androstachys johnsonii Prain, Belowground Carbon Allocation, Error Margins, Root Growth
JOURNAL NAME:
Open Journal of Forestry,
Vol.5 No.4,
April
21,
2015
ABSTRACT: We performed a biomass inventory using two-phase sampling to estimate
biomass and carbon stocks for mecrusse woodlands and to quantify errors in the
estimates. The first sampling phase involved measurement of auxiliary variables
of living Androstachys johnsonii trees;
in the second phase, we performed destructive biomass measurements on a
randomly selected subset of trees from the first phase. The second-phase data
were used to fit regression models to estimate below and aboveground biomass.
These models were then applied to the first-phase data to estimate biomass
stock. The estimated forest biomass and carbon stocks were 167.05 and 82.73
Mg·ha-1, respectively. The percent error resulting from plot
selection and allometric equations for whole tree biomass stock was 4.55% and
1.53%, respectively, yielding a total error of 4.80%. Among individual
variables in the first sampling phase, diameter at breast height (DBH)
measurement was the largest source of error, and tree-height estimates
contributed substantially to the error. Almost none of the error was
attributable to plot variability. For the second sampling phase, DBH
measurements were the largest source of error, followed by height measurements
and stem-wood density estimates. Of the total error (as total variance) of the
sampling process, 90% was attributed to plot selection and 10% to the
allometric biomass model. The total error of our measurements was very low,
which indicated that the two-phase sampling approach and sample size were
effective for capturing and predicting biomass of this forest type.