Ecological network - Wikipedia, the free encyclopedia. An ecological network is a representation of the biotic interactions in an ecosystem, in which species (nodes) are connected by pairwise interactions (links). These interactions can be trophic or symbiotic. Ecological networks are used to describe and compare the structures of real ecosystems, while network models are used to investigate the effects of network structure on properties such as ecosystem stability. Properties of ecological networks.
Results of this work have identified several important properties of ecological networks. Complexity (linkage density): the average number of links per species. Explaining the observed high levels of complexity in ecosystems.
In food webs, the level of connectance is related to the statistical distribution of the links per species. The distribution of links changes from (partial) power- law to exponential to uniform as the level of connectance increases. The degree distributions of food webs have been found to display the same universal functional form. The degree distribution can be split into its two component parts, links to a species' prey (aka. Both the in degree and out degree distributions display their own universal functional forms. As there is a faster decay of the out- degree distribution than the in degree distribution we can expect that on average in a food web a species will have more in links than out links.
A focal species in the middle of a cluster may be a keystone species, and its loss could have large effects on the network. Compartmentalization: the division of the network into relatively independent sub- networks. Some ecological networks have been observed to be compartmentalized by body size.
In highly nested networks, guilds of species that share an ecological niche contain both generalists (species with many links) and specialists (species with few links, all shared with the generalists). In mutualistic networks, nestedness is often asymmetrical, with specialists of one guild linked to the generalists of the partner guild. For instance there exist thirteen unique motif structures containing three species, some of these correspond to familiar interaction modules studied by population ecologists such as food chains, apparent competition, or intraguild predation. Studies investigating motif structures of ecological networks, by examining patterns of under/over representation of certain motifs compared to a random graph, have found that food webs have particular motif structures . Use of ecological networks makes it possible to analyze the effects of the network properties described above on the stability of an ecosystem.
Download PDF Opens in a new window. Take for instance Darwin's . Ecological networks and their fragility. Ecological networks and their fragility. Ecological networks and their fragility. Ecological networks and their fragility. Permitted For non-commercial purposes: Read, print & download; Text & data mine; Translate the article; Not Permitted. Reuse portions or extracts from the article in. Ecological networks and their fragility. Ecological networks and their fragility. Ecological networks and their fragility. All interactions can be visualized as ecological networks. Download PDF; Send to a friend. 26 Investigating Fragility in Plant–Frugivore Networks. The basic structural aspects of plant–animal networks and their.
An ecological network is a. Both the in degree and out degree distributions display their own. Use of ecological networks makes it possible to.
Visualisation of Ecological Networks. Ecological networks and their fragility.
Ecosystem complexity was once thought to reduce stability by enabling the effects of disturbances, such as species loss or species invasion, to spread and amplify through the network. However, other characteristics of network structure have been identified that reduce the spread of indirect effects and thus enhance ecosystem stability. The nested structure of mutualisitic networks was shown to promote the capacity of species to persist under increasingly harsh circumstances. Most likely, because the nested structure of mutualistic networks helps species to indirectly support each other when circumstances are harsh. This indirect facilitation helps species to survive, but it also means that under harsh circumstances one species cannot survive without the support of the other.
As circumstances become increasingly harsh, a tipping point may therefore be passed at which the populations of a large number of species may collapse simultaneously. The community of species in an ecosystem is expected to affect both the ecological interaction and coevolution of pairs of species. Related, spatial applications are being developed for studying metapopulations, epidemiology, and the evolution of cooperation. In these cases, networks of habitat patches (metapopulations) or individuals (epidemiology, social behavior), make it possible to explore the effects of spatial heterogeneity. See also. Proceedings of the National Academy of Sciences.
Proceedings of the National Academy of Sciences. Proceedings of the National Academy of Sciences.
Journal of Animal Ecology. Journal of Animal Ecology. Proceedings of the Royal Society B: Biological Sciences. Proceedings of the National Academy of Sciences. R., Allesina, S., & Maritan, A. Krasnov and Robert Poulin. Oikos, 1. 16; 1. 12.
Suweis, S., Grilli, J., & Maritan, A. Disentangling the effect of hybrid interactions and of the constant effort hypothesis on ecological community stability. Proceedings of the Royal Society of London B.
Proceedings of the Royal Society of London B. Journal of Theoretical Biology. H.; Scheffer, M.; Bascompte, J.
Proceedings of the National Academy of Sciences. Burgos, E.; Ceva, H.; Perazzo, R. P. J.; Devoto, M.; Medan, D.; Zimmermann, M.; Delbue, A. M. Journal of Theoretical Biology. Dunne, J. A.; Williams, R. J.; Martinez, N. D. Dunne, J. A.; Williams, R.
J.; Martinez, N. D. Proceedings of the National Academy of Sciences.
Krause, A. E.; Frank, K. A.; Mason, D. M.; Ulanowicz, R. E.; Taylor, W. W. Memmot, J.; Waser, N. M.; Price, M. V. Proceedings of the Royal Society of London B. Okuyama, T.; Holland, J. N. Reuman, D. C.; Cohen, J.
E. Journal of Animal Ecology. Schmid- Araya, J.
M.; Schmid, P. E.; Robertson, A.; Winterbottom, J.; Gjerlov, C.; Hildrew, A. G. Journal of Animal Ecology. Sole, R. V.; Montoya, J. M. Proceedings of the Royal Society of London B. Vazquez, D. P.; Melian, C. J.; Williams, N. M.; Bluthgen, N.; Krasnov, B.
R.; Poulin, R. Williams, R. J.; Berlow, E. L.; Dunne, J.
A.; Barabasi, A. L.; Martinez, N. D. Proceedings of the National Academy of Sciences. Zhang, F.; Hui, C.; Terblanche, J. S. Suweis, S.; Simini, F.; Banavar, J; Maritan, A. H.; Scheffer, M.; Bascompte, J.