Allometric equations and wood density parameters for estimating aboveground and woody debris biomass in Cajander larch ( Larix cajanderi ) forests of northeast Siberia

[摘要] Boreal forests are particularly vulnerable to climate warming,which increases the occurrence of natural disturbances, such as fires andinsect outbreaks. It is therefore essential to better understandclimate-induced changes in boreal vegetation dynamics. This requiresaccurate estimates of variations in biomass across regions and time. Thisremains challenging in the extensive larch forests of northeast Siberiabecause of the paucity of allometric equations and physical properties ofwoody debris needed for quantifying aboveground biomass pools from fieldsurveys. Our study is the first to present values of mean squared diameter(MSD) and specific gravity that can be used to calculate fine dead anddowned woody debris loads in Cajander larch ( Larix cajanderi ) forests usingthe line-intersect sampling approach. These values were derived from fieldmeasurements collected in 25 forest stands in the Republic of Sakha, Russia,and compared with values reported for other prevalent boreal tree species.We developed allometric equations relating diameter at breast height (DBH, at 1.3 m) to stem wood, stem bark, branches, foliage, and aboveground biomass based on measurements of 63 trees retrieved from previous studies.Differences between our allometric models and existing equations wereassessed in predicting larch aboveground biomass in 53 forest stands sampledin the Republic of Sakha. We found that using fine woody debris (FWD)parameters from other boreal tree species and allometric equations developedin other regions may result in significantly lower biomass estimates inlarch-dominated forests of northeast Siberia. The FWD parameters andallometric equations presented in our paper can be used to refine estimatesof aboveground biomass in Cajander larch forests in northeast Siberia.

[学科分类] 大气科学