enaAscendency: Calculates the Ascendency of an Ecological Network

Description

Calculates the average mutual information (AMI), ascendency, overhead, and capacity of input-output networks. It also returns the ratios of ascendency and overhead to capacity. These metrics describe the organization of flow in an ecological network (Ulanowicz 1997).

Usage

enaAscendency(x = "network object")

Arguments

A network object.

Value

AMI: Returns the Average Mutual Information (AMI) in a network. AMI provides a measure of the constraints placed on a given peice of energy matter moving through a network (Patricio et al. 2006)
ASC: Returns the ascendnecy of a network. Ascendency is a scaled form of AMI relative to the total system throughput (Ulanowicz 1997; 2004). Total system throughput is the sum of all activity in a network (Kay et al. 1989).
OH: Returns the overhead of a network. Overhead is the proportion of the capacity in a network that is not used as ascendency (Ulanowicz 2004).
CAP: Returns the capacity of a network. Capacity is defined as the sum of ascendency and overhead (Ulanowicz 2004).
ACS.CAP: Returns the proportion of capacity used by ascendency.
OH.CAP: Returns the proportion of capacity used by overhead.
robustness: Returns the robustness of the network.
ELD: Returns the Effective Link Density of the network(c) (Ulanowicz et al. 2014).
TD: Returns the Trophic Depth of the network(r) (Ulanowicz et al. 2014).

References

Kay, J.J., Graham, L.A., Ulanowicz, R.E., 1989. A detailed guide to network analysis. p. 15-61 In: Wulff, F., Field, J.G., Man, K.H. (eds.) Network analysis in marine ecology. Coastal Estuarine Study Serries. Springer-Verlag, Berlin.

Patrico, J., Ulanowicz, R.E., Pardal, M.A., Marques J.C., 2004. Ascendency as an ecological indicator: a case study of estuarine pulse eutrophication. Estuar. Coast Shelf S. 60, 23-35.

Ulanowicz, R.E., 1997. Ecology, The Ascendent Perspective. Columbia University Press, New York.

Ulanowicz, R.E., 2004. Quantitative methods for ecological network analysis. Comput. Biol. Chem. 28, 321-33 Ulanowicz, R.E., Holt, R.D., Barfield, M., 2014. Limits on ecosystem trophic complexity: insights from ecological network analysis

Examples

Run this code

data(troModels)
enaAscendency(troModels[[6]])

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