Species Interactions in Ecological Networks

Chapter 10

A-B

Interaction edge

A→B

Uni-directional edge

A ^→_← B

Bi-directional edge

A-B, A - B

Strength of interaciton

unweighted vs. weighted

Connectness web

Shows presence of interactions, but not the strength

Network typology

The structure of the network

Includes degrees and link paths

Degrees

Number of edges to other notes

Link paths

From A to B pathway, provides a bridge between groups

Neighbor values

Connection thorugh degrees

Can be in 1st, 2nd, 3rd, etc.

Green food web

Plant-focused, prioritizes energy that enters the system through photosynthesis

Usually a fast system

Brown food web

Focus on energy from detritus

Slower system

Energy flow web

Measure amount of energy (biomass) that flows through a system

Energy is a poor predictor of

Interaciton strength and/or magnitude of an interaction

Funcitonal food web

Measures strength of interactions between species

Functional food webs are used to

Evaluate effects of loss of species

Weak

1 on this figure represents what strength of interaction

Intermediate

2 on this figure represents what strength of interaction

Strong

3 on this figure represents what strength of interaction