Final answer:
The linkage density of a food web is calculated by dividing the total number of feeding relationships by the total number of species in the web.
Step-by-step explanation:
The linkage density of a food web is defined by the number of links (feeding relationships) per species in the web. To calculate the linkage density, you would divide the total number of links (arrows pointing from one species to another that it feeds on) by the total number of species within the food web. In a simplified estuarine ecosystem food web, if you have a diagram that shows multiple species and their feeding relationships, you would count each arrow as a link and then divide that by the number of species shown in the web to determine the linkage density. For example, if there were 10 species and 20 feeding relationships depicted, the linkage density would be 20 divided by 10, yielding a linkage density of 2.