lecture 7&8 Flashcards
(25 cards)
What is an Ecosystem?
a dynamic complex of plant, animal and microorganism communities and their non-living environment.
Can also be described as the biotic and abiotic components of the environment that interact as a functional unit.
What does a well defined ecosystem have?
Strong interactions among its components and week interactions across it’s boundaries
What are the 2 important aspects of an ecosystem
Its species and the functions within
What is Ecosystem Functioning?
The physical, chemical and biological processes or properties that contribute to the self-maintenance of the ecosystem
Basically how the ecosystem regulates itself
What are ecosystem processes?
the interactions and/or rates of change of a variable such as pollination, decomposition, water cycling, carbon cycling, nutrient cycling, etc.
List 2 key cycles in an ecosystem
- The water cycle
- The carbon cycle
What are ecosystem properties?
stable variables:
-Biomass
diverse descriptors of stability:
-Constancy
-Resistance
-Resilience
What are the descriptors of stability?
-Constancy
-Resistance
-Resilience
What is constancy in terms of an ecosystem?
The ability of an ecosystem to resist change in composition and abundance in response to disturbance
Basically living systems that remain unchanged
What is Resistance in terms of an ecosystem?
Systems resistance to a disturbance
Basically how little the variable of interest changes in response to external pressure.
What is Resilience in terms of an ecosystem?
It’s ability to recover
-rate of recovery to a previous state or rate to re-origanize itself
What enhances many ecosystem processes and properties?
High Biodiversity
Different organisms catching different energy resources means what?
Greater efficiency and higher productivity of ecosystems
What are the consequences of biodiversity loss?
The ecosystem becomes unsustainable
What does human disturbance cause on a marine ecosystem?
-Fishing
-Pollution
-Mechanical habitat destruction
-introduction of species and diseases
-climate change
THIS ALL LEADS TO ALTERED ECOSYSTEMS
How do we monitor state, pressure and responses fully within an ecosystem?
The ecosystem assessment framework
What are surrogates in biodiversity?
a component of a system of concern that one can more easily measure or manage than others.
It is used as an indicator species for an attribute or trait.
Why are surrogate measures used in biodiversity?
-complexity or difficulty in measuring the variable of interest.
-resource constraints in monitoring and management may require a more cost-effective yet useful way to assess the ecosystem.
What is Biodiversity Indicators?
A statistical measure of biodiversity that helps scientists, managers and politicians understand the condition of biodiversity and the factors that affect it
What are the key attributes of surrogates?
-cheap feasible ways to measure or manage
-representative of the species/process of interest
-respond in timely and predictable ways to changes in the environment.
What can biodiversity indicators measure?
-population trends
-extent of habitats
-trends in the status of a threatened species
-trends in the impacts of a specific pressure (like fishing on fish stocks)
-coverage of protected areas
some global biodiversity indicators (companies)
-Living Planet Index (LPI)
-Red List Index (RLI)
-IUCN Red List
-WWF
-Wild Bird Index
-Marine Trophic Index
-
What is the CBD strategic plan for biodiversity goals?
- Have where feasible and bring close to 0 the rate of loss of habitats
- Establish a conservation target of 17% for terrestrial and inland waters and 10% for marine and coastal.
- Restore at least 15% of degraded areas
- Make special efforts to reduce the pressures faced by coral reefs
How many species occur in Ireland?
> 31,000
