TOPIC 5 (LEC & LAB) - Community Ecology Flashcards
Organisms found in trophic structure
Autotrophs
Herbivores
Carnivores
Decomposers
the relative abundance of species in communities; the proportion each species represents of all individuals in the community
Species evenness
The loss of a ________ species can lead to population crashes and extinction of other species in a community that depends on it for certain services.
keystone
A sampling tool that may be place randomly in an area or at intervals along a transect line.
Quadrat
A level in biodiversity that refers to the variation in the ecosystems found in a region
Ecosystem diversity
Species that play roles affecting many other organisms in an ecosystem; their effect on the community is disproportionate to their numerical abundance
KEYSTONE SPECIES
Considerations in planning ecological surveys
Timing of surveys (nearly all species have some seasonality to their life cycle)
Survey validity (fewer survey visits/reduced survey area may not give reliable indication of species presence)
Levels of biodiversity
Genetic
Species
Ecosystem
Species diversity is defined in the basis of?
Species richness
Species evenness
It suggests that the length of a food chain is limited by the inefficiency of energy transfer along the chain
Energetic hypothesis
Refers to the feeding relationships between organisms and the community
Trophic structure
minimum values of H’ is ____ (value for a community with a single species, a higher value of H’ indicates a more diverse community)
0
A level in biodiversity that refers to the variations within and among population in a species, as well as the difference between and among species
Species diversity
A combination of the number of species and their relative abundance
SPECIES DIVERSITY
They may be competitively dominant—superior in exploiting key resources such as space, water, nutrients, or light
FOUNDATION SPECIES
A level in biodiversity that refers to variations in the nucleotides, genes, chromosomes, or whole genomes of organism
Genetic diversity
a mathematical measure of species diversity in a given community
Diversity index
The position an organism occupies in a food chain
TROPHIC LEVEL
it is used to compare diversity of communities based on species richness and relative abundance
Shannon-Wiener index (H’)
a measuring tape (sampling tool) stretched along two points; allows to see the effects of abiotic factors on the organism distribution
Transect
A species that has strong effects on its community as a result of its large size, high abundance, or pivotal role in community dynamics
FOUNDATION SPECIES
A group of food chains linked together
FOOD WEB
Surveys for habitats and species, one of its objects is to identify any potential constraints to the development resulting from the presence of important habitats or species
ECOLOGICAL SURVEYS
The transfer of chemical energy from its source through different consumers
FOOD CHAIN
A biogeographic region that is both a significant reservoir of biodiversity and is threatened with destruction
BIODIVERSITY HOTSPOT
the number of species in the community
Species richness
Includes attributes such as the number of species, the relative abundance of species, and the kinds of species comprising a community
COMMUNITY STRUCTURE
An association of interacting species inhabiting some defined area
COMMUNITY
