Rossberg A G, Yanagi K, Amemiya T, Itoh K
Yokohama National University, Graduate School of Environment and Information Sciences, Yokohama 240-8501, Japan.
J Theor Biol. 2006 Nov 21;243(2):261-72. doi: 10.1016/j.jtbi.2006.06.019. Epub 2006 Jun 29.
The trophic link density and the stability of food webs are thought to be related, but the nature of this relation is controversial. This article introduces a method for estimating the link density from diet tables which do not cover the complete food web and do not resolve all diet items to species level. A simple formula for the error of this estimate is derived. Link density is determined as a function of a threshold diet fraction below which diet items are ignored ("diet partitioning function"). Furthermore, analytic relationships between this threshold-dependent link density and the generality distribution of food webs are established. A preliminary application of the method to field data suggests that empirical results relating link density to diversity might need to be revisited.
营养级联密度与食物网的稳定性被认为是相关的，但这种关系的本质存在争议。本文介绍了一种从饮食表估计连接密度的方法，该饮食表并未涵盖完整的食物网，也未将所有饮食项目解析到物种水平。推导了该估计误差的一个简单公式。连接密度被确定为一个低于该阈值饮食比例的函数，低于该比例的饮食项目将被忽略（“饮食划分函数”）。此外，建立了这种依赖阈值的连接密度与食物网普遍性分布之间的解析关系。该方法在实地数据中的初步应用表明，将连接密度与多样性相关联的实证结果可能需要重新审视。
