气候变化领域集成服务门户(CCPortal): Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations

CCPortal

DOI	10.1016/j.foreco.2018.11.010
	Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations
	Kohyama T.S.; Kohyama T.I.; Sheil D.
发表日期	2019
ISSN	0378-1127
起始页码	729
结束页码	740
卷号	433
英文摘要	There is widespread interest in ensuring that assessment and knowledge of changes in forest biomass, and associated carbon gains or losses, are accurate and unbiased. Repeated measurements of individually-marked trees in permanent plots permit the estimation of rates of biomass production by tree growth and recruitment and of loss from mortality. But there are challenges, for example, simple estimates of production rate (i.e., the sum of biomass gain by growth of surviving trees and new recruits divided by census duration) decline as the census interval increases due to unrecorded growth. Even if we allow for these unobserved changes, additional biases may arise due to the non-independence of growth and mortality and to the heterogeneity and compositional changes within the forest. Here we examine these issues and demonstrate how problems can be minimized. We provide and compare alternative approaches to estimate net biomass production and loss from tree growth and mortality. Under the assumption that specific rates of biomass production and loss, i.e., turnover, are constant over time, we derive estimates of absolute biomass turnover rates that are independent of census duration. We show census-interval dependence of simple turnover rates grows with increasing specific turnover rates. While the time-dependent bias in simple estimates has previously been suggested to increase in proportion to the square of production, we show this relationship is approximately linear. Correlations between stem growth and mortality do not influence our estimates. We account for biomass gain by recruited stems without discounting their initial biomass in production estimates. We can reduce additional biases by accounting for differences in turnover among subpopulations (such as species, sites) and changes in their abundances. We provide worked examples from four forests covering a range of conditions (in Indonesia and Japan) and show the effects of accounting for these biases. For example, over five years in an Indonesian rain forest, simple estimates and instantaneous estimates neglecting species heterogeneity underestimated production by 4.9% and 1.6%, respectively when compared to comprehensive (instantaneous species-structured) estimates. © 2018 Elsevier B.V.
英文关键词	Census interval; Demography; Ecosystem; Growth; Mortality; Net primary production; Population ecology; Recruitment; REDD+; Wood production
语种	英语
scopus关键词	Biomass; Ecosystems; Forestry; Growth (materials); Population statistics; Surveys; Census interval; Demography; Mortality; Net primary production; Population ecology; Recruitment; REDD; Wood production; Ecology; biomass; demography; forest ecosystem; growth; measurement method; mortality; net primary production; population ecology; subpopulation; terrestrial ecosystem; tree; wood; Biomass; Ecosystems; Forestry; Mortality; Recruitment; Surveys; Indonesia; Japan
来源期刊	Forest Ecology and Management
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156241
作者单位	Faculty of Environmental Earth Science, Hokkaido University, Sapporo, 060-0810, Japan; Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway; Center for International Forestry Research (CIFOR), Kota Bogor, Jawa Barat 16115, Indonesia
推荐引用方式 GB/T 7714	Kohyama T.S.,Kohyama T.I.,Sheil D.. Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations[J],2019,433.
APA	Kohyama T.S.,Kohyama T.I.,&Sheil D..(2019).Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations.Forest Ecology and Management,433.
MLA	Kohyama T.S.,et al."Estimating net biomass production and loss from repeated measurements of trees in forests and woodlands: Formulae, biases and recommendations".Forest Ecology and Management 433(2019).