6 FUNCTIONAL GROUPS Flashcards
How organisms respond to various ecological factors and in turn how these responses affect ecosystem functioning is fundamental to discerning ecological what?
Ecological consequences of change
What do taxon based approaches compare? What do they often use? Why don’t identified patterns necessarily point to causation/provide mechanistic understanding from a functional standpoint?
- Compare species assemblage in relation to environmental conditions
- often using multivariate statistical approaches
- any identified patterns don’t necessarily point to causation or provide mechanistic understanding from functional standpoint bc taxonomic position of a species isn’t a reliable indicator of ecological role of species
What is the focus in trait based approaches?
- How the components of biodiversity influence ecosystem properties
- Therefore are touted as offering greater mechanistic understanding that can be applied more generally.
What are functional traits?
Those that define species in terms of their ecological roles; how they interact with the environment & other species.
What are biological species traits? What do they relate to?
The attributes of a species.
They relate to morphological, biochemical, physiological, structural, phenological, behavioural, and/or any other functionally relevant life-history features of the organism
What is a functional effect trait? What can they help us understand?
What is a functional response trait? What can they help us understand? What is functional redundancy?
- Any trait which alters specific community or ecosystem properties. They can help us understand organism-sediment interactions, how species effect ecosystem processes, and the delivery of ecosystem functioning.
- Any trait responding to external forcing that alters the performance or fitness of an individual, e.g. via its effects on growth, reproduction and survival. Can help us understand how communities may change in resp to environmental change.
- Functional redundancy = overlap in functional capability (several species contribute/respond in the same way as other species)
What is a functional group?
A set of organisms sharing similar responses to the environment (e.g. temp, salinity, nutrients, competition) / have similar effects on ecosystem processes (e.g. bioturbation) / functioning (e.g. productivity, nutrient cycling)
What is a good strategy for understanding effects of functional diversity on ecosystem processes?
Nesting functional response groups within functional effect groups
Unifies the processes of community assembly and biodiversity effects on ecosystem function.
What are some examples functional trait category/associated categorised trait modality pairings?
body mass -> biomass, biovolume or other size measurement
morphology -> shape, structure & network properties
larval type -> planktotrophic, lechithotrophic, direct development
living habit -> sedentary, errant, attached, tube or burrow dweller
activity -> periodicity (occasional, cyclic, continuous) or mode (e.g. bioturbation, reworking modes)
feeding habit -> detritivore, herbivore, carnivore, omnivore, scavenger, predator, parasitic
resource capture -> jawed, siphon, tentaculate, pharynx, radula
mobility -> sedentary, semi-mobile, mobile
movement -> byssus, swimmer, rafter/drifter, crawler, burrower
environmental position -> pelagic, epibenthic, benthic, physiological requirements
Why is size (typically biomass) not necessarily a reliable indicator of species functional distribution?
reflects a range of other factors, like life stage and recent environmental conditions.
How do tube building species/species with protruding physical structures act as sediment stabilisers?
How do species that disproportionately mix the sediment profile act as sediment destabilisers?
- act as baffles and redirect current flow, and large stands of species can raise the benthic boundary layer
- can increase porosity and erodibility of the sediment surface
What are the different functional feeding groups? (6)
- engulfer
- shredder
- piercer
- scraper
- collector
- filterer
What are the 6 trophic feeding groups?
suspension deposit carnivore omnivore herbivore
What are the 7 types of bioturbation?
- epifaunal
- surficial modifiers
- biodiffusers
- gallery biodiffusers
- upward conveyors
- downward conveyors
- regenerators
What is the difference between classification and ordination approaches to group species into functional groups?
Classification techniques: tend to assign species on assumed a priori defined species roles & tend to be based on evidence from lit & expert knowledge. Groups similar species based on assumed traits.
Ordination: studies tend to use continuous rather than categorical traits & identify functional group membership using statistical techniques based on measured data. Groups similar species based on measured traits.
