Biodiversity is not always top-down regulated

One can think of different ways that biodiversity can be regulated in the framework of food-webs or more generally networks of interactions:

• Top-down: the effect of predation, hervibory, parasitism

• Botton-up: food/nutrients

• Disturbance:

In a more microscopic way could also have stabilizing influence or not

• Trophic interactions

• Competitive or negative interactions

• Mutualistic or positive interactions

• No interactions (Neutral)

• Environment-species interactions

Hypothesis: The Diversity of Interaction Types have influence on the Community Stability

The community structure effect on population dynamics may not be correctly evaluated in the absence of interaction type-mixing information

However, empirical data on hybrid community interaction webs are limited.

A possible test of our hypothesis is to compare the composition of interaction types between different communities under varying levels of disturbance. An ecosystem under more-intensive disturbance is expected to have a more stabilizing composition of interaction types.

1. Mougi A, Kondoh M. Diversity of Interaction Types and Ecological Community Stability. Science (80- ). 2012;337: 349–351. doi:10.1126/science.1220529

2. Terborgh JW. Toward a trophic theory of species diversity. Proc Natl Acad Sci. 2015;112: 11415–11422. doi:10.1073/pnas.1501070112

3. Reed DC, Rassweiler A, Carr MH, Cavanaugh KC, Malone DP, Siegel DA. Wave disturbance overwhelms top-down and bottom-up control of primary production in California kelp forests. Ecology. 2011;92: 2108–2116. doi:10.1890/11-0377.1

4. Carrara F, Giometto A, Seymour M, Rinaldo A, Altermatt F. Inferring species interactions in ecological communities: a comparison of methods at different levels of complexity. Methods Ecol Evol. 2015;6: 895–906. doi:10.1111/2041-210X.12363

5. Kéfi S, Berlow EL, Wieters EA, Navarrete SA, Petchey OL, Wood SA, et al. More than a meal… integrating non-feeding interactions into food webs. Ecol Lett. Blackwell Publishing Ltd; 2012;15: 291–300. doi:10.1111/j.1461-0248.2011.01732.x