Relationship between the virtual dynamic thinning line and the self-thinning boundary line in simulated plant populations
Authored by Gang Wang, Kang Chen, Hong-Mei Kang, Juan Bai, Xiang-Wen Fang
Date Published: 2008
DOI: 10.1111/j.1744-7909.2007.00618.x
Sponsors:
No sponsors listed
Platforms:
C
Model Documentation:
Other Narrative
Mathematical description
Model Code URLs:
Model code not found
Abstract
The self-thinning rule defines a straight upper boundary line on log-log
scales for all possible combinations of mean individual biomass and
density in plant populations. Recently, the traditional slope of the
upper boundary line, -3/2, has been challenged by -4/3 which is deduced
from some new mechanical theories, like the metabolic theory. More
experimental or field studies should be carried out to identify the more
accurate self-thinning exponent. But it's hard to obtain the accurate
self-thinning exponent by fitting to data points directly because of the
intrinsic problem of subjectivity in data selection. The virtual dynamic
thinning line is derived from the competition-density (C-D) effect as
the initial density tends to be positive infinity, avoiding the data
selection process. The purpose of this study was to study the
relationship between the virtual dynamic thinning line and the upper
boundary line in simulated plant stands. Our research showed that the
upper boundary line and the virtual dynamic thinning line were both
straight lines on log-log scales. The slopes were almost the same value
with only a very little difference of 0.059, and the intercept of the
upper boundary line was a little larger than that of the virtual dynamic
thinning line. As initial size and spatial distribution patterns became
more uniform, the virtual dynamic thinning line was more similar to the
upper boundary line. This implies that, given appropriate parameters, the virtual dynamic thinning line may be used as the upper boundary line
in simulated plant stands.
Tags
interference
Size distribution
Density
Rule
General-model
Asymmetric competition
Allometry
Growth analysis
Ecological field-theory
Neighborhood models