Bias in estimates of primary production: An analytical solution

Osvaldo Sala, M. E. Biondini, W. K. Lauenroth

Research output: Contribution to journalArticle

63 Citations (Scopus)

Abstract

This paper addresses the issue of the effect of random error upon the estimates of above-or belowground net primary production (NPP). We show that ramdom errors in estimates of biomass do not compensate but always result in a positive bias in estimates of NPP. Second, we demonstrate that the larger the number of time intervals considered, the higher is the positive bias or overestimation error. An effect similar to an increase in the number of sampling periods is obtained by increasing the number of components utilized in estimating NPP. These are usually taxonomic or functional (depth, live, recent dead, etc.) components. We calculate the magnitude of the overestimation error as a function of the size of the difference in two sequential estimates of biomass and the variability associated with them. We propose a method that uses this error to correct the estimates of NPP for the positive bias resulting from random errors and to develop confidence intervals for the corrected NPP. We suggest that this method will remove the positive bias from estimates of NPP upon which nutrient budgets, energy flow and trophic webs rely. The concepts presented will help in the design of experiments that use production as a response variable.

Original languageEnglish (US)
Pages (from-to)43-55
Number of pages13
JournalEcological Modelling
Volume44
Issue number1-2
DOIs
StatePublished - 1988
Externally publishedYes

Fingerprint

net primary production
primary production
primary productivity
nutrient budget
energy flow
biomass
confidence interval
experimental design
nutrients
sampling
methodology
experiment

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecological Modeling
  • Ecology

Cite this

Bias in estimates of primary production : An analytical solution. / Sala, Osvaldo; Biondini, M. E.; Lauenroth, W. K.

In: Ecological Modelling, Vol. 44, No. 1-2, 1988, p. 43-55.

Research output: Contribution to journalArticle

Sala, Osvaldo ; Biondini, M. E. ; Lauenroth, W. K. / Bias in estimates of primary production : An analytical solution. In: Ecological Modelling. 1988 ; Vol. 44, No. 1-2. pp. 43-55.
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