ascendency.html

Ascendency

Ulanowicz, Robert E.1997. Ecology, the ascendent perspective. Columbia University Press.201 pages. QH 540.5 .U42

ulanowicz-1997.html

Ascendency is a measure of the organized complexity of a network.

• overhead functions (encumbered network functions - just to keep working)
  • inputs
  • exports
  • dissipations (losses)
  • pathway redundancy
• ascendency (value of the organizational structure)

It consists of the sum of all the flows weighted by the specificity of each flow.

AMI

Ulanowicz figure 4.6

shows how fewer flows with high specificity leads to higher AMI

flow

 

 

Network ascendency can be related to the resiliency cycle.

Hollings resiliency cycle

stored capital (or potential) vs. organization (connectivity)

Figure 4.10 from Ulanowicz 1997

 

Ulanowicz version

biomass vs. mutual information flow structure

Figure 4.11 from Ulanowicz 1997

what is a "healthy" network

by Ulanowicz's (** ref **) definition

responds to stress by improving the structure of the network

figure 7.2 from Ulanowicz 1997