|
Titel |
Tree height and tropical forest biomass estimation |
VerfasserIn |
M. O. Hunter, M. Keller, D. Victoria, D. C. Morton |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1726-4170
|
Digitales Dokument |
URL |
Erschienen |
In: Biogeosciences ; 10, no. 12 ; Nr. 10, no. 12 (2013-12-20), S.8385-8399 |
Datensatznummer |
250085487
|
Publikation (Nr.) |
copernicus.org/bg-10-8385-2013.pdf |
|
|
|
Zusammenfassung |
Tropical forests account for approximately half of above-ground carbon
stored in global vegetation. However, uncertainties in tropical forest
carbon stocks remain high because it is costly and laborious to quantify
standing carbon stocks. Carbon stocks of tropical forests are determined
using allometric relations between tree stem diameter and height and
biomass. Previous work has shown that the inclusion of height in biomass
allometries, compared to the sole use of diameter, significantly improves
biomass estimation accuracy. Here, we evaluate the effect of height
measurement error on biomass estimation and we evaluate the accuracy of
recently published diameter–height allometries at four areas within the
Brazilian Amazon. As no destructive sample of biomass was available at these
sites, reference biomass values were based on allometries. We found that the
precision of individual tree height measurements ranged from 3 to 20% of
total height. This imprecision resulted in a 5–6% uncertainty in biomass
when scaled to 1 ha transects. Individual height measurement may be replaced
with existing regional and global height allometries. However, we recommend
caution when applying these relations. At Tapajos National Forest in the
Brazilian state of Pará, using the pantropical and regional allometric
relations for height resulted in site biomass 21% and 25% less than
reference values. At the other three study sites, the pantropical equation
resulted in errors of less that 2%, and the regional allometry produced
errors of less than 12%. As an alternative to measuring all tree heights
or to using regional and pantropical relations, we recommend measuring
height for a well-distributed sample of about 100 trees per site. Following
this methodology, 95% confidence intervals of transect biomass were
constrained to within 4.5% on average when compared to reference values. |
|
|
Teil von |
|
|
|
|
|
|