ISSN:
1365-2494
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Frequency data from different-sized plots are generally accepted as being incomparable. However, how basal frequency data are influenced by plant basal diameter is not well known. Computer simulations were used to determine the influences of grass plant basal diameter on basal frequency data. Basal frequency, basal area and density were estimated with simulated 5 × 10 cm and 20 × 50 cm rectangular plots. Simulated plants had basal diameters ranging from 1.9 to 12.7 cm.Basal diameter had a significant effect on the relationship between frequency and both basal area and density. As differences in plant size increase, the effect on basal frequency becomes larger and the likelihood of an ecologically important influence also increases. Thus, frequency data should not be used to compare relative abundance of species, unless corrections are made for differences in plant basal diameter among species. Additionally, frequency data should not be used to monitor change in abundance of a species through time, unless mean plant basal diameter can be assumed to remain relatively constant.Basal frequency data could be used to ‘signal’ when change has occurred. Then, other sampling methods must be used to determine the nature and direction of change or relative species abundance. For frequency data, the simplicity of collection may be offset by difficulty in interpretation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2494.1994.tb02018.x
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