Zusammenfassung der Ressource
Ecosystem functioning and services
- Ecosystem and services
- Ecosystems are dynamic interrelated
collections of living and non-living
components organised in self-regulating
units
- Ecosystem by scale
- Microbial to global
- Biotically defined
- Foundation species
- Ecological unit
- Abiotically
defined
- Nature of physical
environment
- Systems
- Systems are built on connectivity,
within ecosystems or between
ecosystems.
- Systems by connectivity
- E.g. fish moving between geographical regions
- A system defined by connectivity: subcomponents of system cannot be treated in isolation
- Members of
the system
- Spatial
relationship
- e.g. Ecosystems are usually biotically
or abiotically defined
- Connectivity of
processes
relationship
- E.g. Food-web,
Nutrients etc
- Network of
ecosystems
- Ecosystem function
- What ecosystems do: it is an old concept
- Nutrient uptake
- Bioturbation
- Biomass production
- Functions at
different scales
- Microbial scale
- Plankton ecosystem
- Primary production etc
- Big scale
- Plankton
ecosystem
- Regulation of fisheries
and food webs etc
- Global
ecosystem
- Climate regulation
- 'Functioning'
- Operating of and/ or performances of:
- Selected processes and
properties of the system.
E.g. oxygen uptake,
bioturbation.
- The system as a whole.
E.g. How the systems
life-persistence
mechanisms work.
- The roles played in the workings of the system. E.g. role
played by predator, prey etc. NTR: Same role can
performed by different actors.
- Providing benefit to people. ECOSYSTEM
SERVICES. Noticable difference is the
benefit a system provides.
- Ecosystem services
- Ecosystem provide goods and services to
people. This distunguishes itself from
"functions".
- "Services by natural environments that benefit people"
- Four classes of
services. (PRSC).
- Provisioning service. E.g.
food, water etc
- Regulation service.
E.g. Carbon
sequestration,
Coastal proctection
- Supporting
services. e.g.
Nutrient cycling,
primary production
- Cultural
services
- Constanza et al. 1997. 33 trillion
dollars for global ecosystem
services per annum
- Cost benefit analysis: cost
of maintaining/ cost of
losing
- Failing functions and services
- Will occur when services or expected function change or fail.
- E.g. natural coastal protection loss leads to terrestrial land erosion
- E.g Poor water quality for fish leads to mortality
- Why do ecosystems fail?
- There are key cornerstones
that must be met
- Intrinsic abiotic and biotic properties
- Species compostion
- Chemical and physical gradients
- Extrinsic forcing agents and links
- Drivers such as climate weather tc.
- Factors associated with biotic
and abiotic connectivity.
- Thresholds
- Tolerance and gradient
ranges
- Systems exist within their tolerance range
along gradients in abiotic and biotic factors.
- Systems lie along multiple
interacting gradients.
- Functional regime
- Made up of the
intrinsic biotic and
abiotic properties
- Extrinsic
forcing agents
and links
- Conclusion
- Function will depend on where, along the gradients of
interacting intrinsic and extrinsic regimes the system is
positioned.
- Shift a gradient and it will affect the
system and the whole functional
regime.
- Systems might collapse if the nature of
inherent and external properties shift
too far from system tolerance ranges.
- Regime shift
- Shift in general characteristics
of biotic/ abiotic factors
- Extremes can also result in regime shifts. But are
determined by value and duration