Food webs as a tool for the study of diversity and complexity of ecosystems

In view of the increasing environmental deterioration and its harmful effect on species richness, it is important to find the adequate methodology for the study and management of diversity. The present review presents a short historical account of food web analyses, the different types of food webs and the most common methodological analyses of them. Non-weighed webs, though simple in their construction do represent structural and diversity aspects in a quantitative manner. Weighed webs, have the advantage of using the flow of matter between species but the amount and quality of data is high and sometimes difficult to gather. Bipartite webs, which can be weighed or not, are a special case used in biogeographical or parasite studies. For the 3 web types, it is possible to measure species richness and diversity, matter flow diversity and other topological characteristics most of which are useful for the decision making in an ecosystem management program.