✦ LIBER ✦

Validating the reference unit method of aboveground phytomass estimation on shrubs and herbs

✍ Scribed by Alan T. Carpenter; Neil E. West

Book ID: 104621229
Publisher: Springer Netherlands
Year: 1987
Tongue: English
Weight: 373 KB
Volume: 72
Category: Article
ISSN: 1385-0237
DOI: 10.1007/bf00044836

No coin nor oath required. For personal study only.

✦ Synopsis

The validity of the reference unit method for ocularly estimating aboveground phytomass non-destructively was assessed on two shrubby and two herbaceous species using three observers. A calibration equation was developed for each observer-plant species combination using measured dry masses of harvested plants. These equations were then used to estimate phytomass of additional individuals of the same species (validation group), which were also later harvested. Average relative errors of estimated individual plant masses in the validation group ranged from 17.1 to 47.3% among the observers. However, when phytomass estimates of the observers were averaged and the resulting means averaged for the validation groups, the relative error of estimate of the mean plant biomass dropped to between 0.2 and 8.0°70. The reference unit method appears to be a valid way to estimate the mean phytomass of a group of plants, as is frequently required in community-or population-level studies.

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