Week 7: Species Richness Flashcards
Lecture, Labs, Readings (terms)
Species Richness
The number of species in a community
Diversity Index
Measures that combine both species richness and the evenness or equitability of the distribution of individuals among those species
Evenness
The similarity of abundances of each species in an environment.
Niche breadth
The diversity of resources used or environments tolerated by an individual, population, species, or clade.
Niche overlap
The situation in which co-occurring species share parts of their niche space with each other. High niche overlap may lead to conflictual interactions (such as competition and exclusion) for some species
Productivity hypothesis
The importance of climate in determining productivity at the lowest trophic level - the plants and microbes — and the resources these then provide for herbivores and then carnivores further up the food chain.
Energy hypothesis
Emphasizes the
direct role of energy (often measured by environmental temperature) on organisms throughout the community.
Eutrophication
The gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aging aquatic ecosystem such as a lake.
Particulate organic matter (POM)
Fragments of undecomposed biomass that can be rapidly degraded in the water column
Alpha diversity
Refers to diversity at a local scale (within a community), so it is high when there are many species within each
community.
Beta diversity
Refers to the differences among communities within a region, so it is high when different communities in a region differ in the species they contain.
Gamma diversity
Refers to diversity at the whole regional scale (collections of communities). It therefore combines a- and f-diversity and is highest when both individual communities are diverse and the communities in a region differ.
Potential evapotranspiration (PET)
The amount of water that would evaporate or be transpired from a saturated surface, and hence a measure of atmospheric energy;
Net Primary Productivity (NPP)
Gross primary productivity minus the rate of energy loss to metabolism and maintenance.
Benthic
The study of organisms that make up bottom communities (sediments, seagrass communities and rock outcrops) in lakes, streams, estuaries and oceans, to determine environmental health and conduct environmental impact studies.
Intermediate disturbance hypothesis
Suggests that local species diversity is maximized when ecological disturbance is neither too rare nor too frequent.
Species-area relationship
The relationship between the number of species of plants and animals and the size of a specific area of land
Turnover
Change in species composition observed in a single location through time
Why does pH not fluctuate in the Waterloo Region?
pH does not Fluctuate because of our Limestone bedrock, making our water basic.
How does water temperature affect aquatic life?
Important for fish and invertebrate habitat, some species require cold
water streams.
Why is Dissolved oxygen (DO) important for aquatic life?
a). Necessary for aquatic organisms and bacteria.
b). Fast moving stream with riffles, rocky substrate will have higher DO.
c). Inverse relationship between water temperature and DO.
Why is Velocity important for aquatic life?
a). Stream flow affects bank erosion, transport of nutrients, stirs up substrate and impacts aquatic habitat.
b). Faster flowing streams result in higher DO especially if the substrate is gravelly or rocky.
Why is the Substrate of a stream important for aquatic life?
a). Will affect clarity of a stream
b). Will affect what organisms can live there. Generally, a gravelly or rocky substrate means higher DO than a silty substrate.
Why is the type of stream important for Aquatic life?
Riffles and runs generally mean a higher DO and lower water temperatures than pools or flats resulting in higher water quality.
Why is stream depth & width important to Aquatic life?
Stream width and depth change according to factors such as flooding events, precipitation and influences upstream (e.g. dam
release)
What are Benthic Invertebrates?
Benthic Invertebrates are
bottom-living organisms that
inhabit the substrate of water
bodies for at least part of their
life cycle.
Why are Benthic Invertebrates important to determine the water quality of a stream?
Invertebrates are an important
indicator of water quality
because different groups are
affected differently by physical
and chemical properties of
water.
Laurel Creek Site features
a). Potential contaminant and nutrient sources upstream
b). Channel straightening
c). Adjacent land uses that destabilize banks
d). Sediment loading or deprivation
e). Barriers or dams nearby
f). Springs or seeps
g). Riparian vegetation
h). Other activities that could influence biota or habitat
TSS and Turbidity
Total Suspended Sediments (TSS) and turbidity are similar
parameters, TSS is a quantitative measurement of sediment suspended in water, turbidity is a measurement of how clear or murky the water is.
How does TSS and Turbidity affect aquatic life?
a). High TSS or turbidity affects photosynthesis and can influence habitat suitability for some aquatic life.
b). Contaminants such as phosphorus, metals and pesticides can
attach to sediment particles in the water
Biotic indices
A family of weighted summaries that combine
the known pollution tolerances of taxa with richness or abundance
information.
Richness & Evenness
Key information pieces that can be
combined to produce diversity indices
