Lecture 5.txt

What species a community contains and the relative abundances of those species

Only if it is able to colonize and persist there

Species that are colonized – those that are extinct LOCALLY

Small population, exclusions (predators, pathogens, competitors), lacking of a resource, species can’t tolerate the local conditions

Environmental gradients, disturbances, and changing climate, elevation, soil type

A straight line used for ecological surveys that shoes species turnover through space

Habitat Structure

Disturbance events; volcanic eruptions, wildfires, hurricanes, landslides, human activities.

The process by which species replace one another in a predictable sequence

It can undergo ‘succession’ which leads to a community that resembles the original one

It undergoes ecological transition.

The environmental tolerances of a species which define WHERE it can live; and it also refers to the ways a species obtains energy and materials and to patterns of interactions with other species in the community

Autotrophs. They convert solar energy into a form that can be used by the rest of the community.

Organisms that get energy by breaking apart organic compounds that were assembled by other organisms.

Organisms that eat primary producers. Herbivores

Eat primary consumers (carnivores)

Eat secondary consumers

Eat tertiary consumers

Feed from multiple trophic levels

Detritivores. Feed on waste products or dead bodies of organisms

Recycling materials and breaking down organic matter into inorganic components for primary producers to reabsorb.

Food webs

Gross product productivity. The total amount of ENERGY that primary producers convert to chemical energy

Net primary productivity. Energy contained in tissues of the primary producers and is available for consumption

Change in biomass of primary producers (dry mass) per unit of time

10%

Not all biomass ingested by next trophic level, some injected matter is indigestible so the animal poops it out, and organisms that use a lot of the energy they make to fuel their own metabolism

The sum of positive and negative contributions of species with which it interacts

The number of species in the community

The distrubtion of species’ abundances

Species richness and evenness

The species that are more abundant than the rare ones

GPP and NPP

Sampling, niche complementarity

Wen communities have many types of species, they are more likely to have some species with a very strong influence on community output

Communities with many species can be better able to use all the available resources

Plant groups that differ in traits such as ability to grow in warm vs cool weather, association with Nitrogen fixing bacteria, allocation to growth vs reproduction, etc.

Tropics

Maybe because the climate is so stable and hasn’t been affected by glacial cycles; they have higher abundant solar energy and productivity, environmental heterogeneity.

That diversity is higher in more structurally COMPLEX habitats

Macarthur and Wilson

Populations become smaller, amount of habitat decreases, average patch size decreases, patches become more isolated, human modified habitat can be a barrier to dispersal

Cluster habitat fragments and connect them with dispersal corridors

Keep a large patch of the original habitat.