Trophic cascades are changes in lower trophic levels as a result of a change in the abundance of predator populations. One example is the removal of wolves from an ecosystem might result in an increase in the number of elk and a decrease in the vegetation the elk feed on.(See Yellowstone National Park's famous example of a trophic … [Read more...]
Keystone species – Liz Mace
A keystone species is one that has a large impact on its community. They have an important role in the ecosystem’s function and without them there would be very significant changes in the ecosystem. A keystone species is different than a dominant species, as a dominant species is more abundant, while a keystone species if very impactful but less abundant. They alter their … [Read more...]
Eutrophication – Liz Mace
Eutrophication occurs when chemical nutrients, usually containing nitrogen or phosphorus, are added to an ecosystem. These chemicals change the habitat and the plants and animals that live in the ecosystem. Excessive growth occurs, which can end up contaminating water supply and compromise the sustainability of resources in the area. Oxygen is consumed more quickly, and the … [Read more...]
Metapopulation- Matt Brantley
Metapopulation consists of separated populations of the same species that interact on some level. It describes a species that is present in fragmented habitats. Because of this separation, these populations tend to have a lot of fluctuation in population size, which sometimes results in extinction. A metapopulation is generally considered to consist … [Read more...]
Species Interactions – David Rogers
Species interactions are the way in which organisms in a system are affected by each other. There are five major types of interactions among species: parasitism, mutualism, competition, predation, and commensalism. Many species interactions are affected and dependent on natural and renewable resources. For example, the availability and abundance of a … [Read more...]