Bioassessment and biomonitoring:

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• Bioassessment and biomonitoring
• some general principles

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• Whats the difference?
• Bioassessment
• - the use of living organisms to assess aspects
  of the integrity (condition, health) of the
  environments in which they live
• OR
• - the process of determining if human activity
  has altered the biological properties of an
  ecosystem

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• Biomonitoring
• the use of living organisms to track conditions
  in the environments in which they live
• OR
• the systematic use of biological responses to
  evaluate environmental changes within a
  quality-control programme

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• A metric is a value calculated from a particular
  set of measurements.
• An indicator is a feature (biological, physical,
  chemical, a metric, an index) that reflects
  specific condition or change in condition.
• An index is a numerical indicator derived from a
  series of metrics.

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• Indices can be based on metrics derived from
• the biota
• e.g. SASS (inverts) VEGRAI (riparian veg.)
• or
• physical features
• e.g hydrological, habitat indices
• or
• mixed features
• e.g. WetEcoservices derived from
  socio-economic biotic indices

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• Bioassessment uses components of the biota to
  reflect aspects of e.g.
• - water chemistry
• - hydrology (e.g. water level)
• - availability of nutrients
• - ecosystem integrity (health)
• - suitability for particular purposes (i.e.
  quality) etc.
• e.g. the Saprobien Index organic
  pollution

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Why bioassessment?

• While chemical and physical analyses are
• - reliable (accurate, repeatable)
• - provide instant snapshots
• They are
• - limited to the period of sample collection
• - limited to the constituents measured
• - expensive (if comprehensively done)
• - limited by sensitivity of the methods used
  low concentrations cannot be detected.

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• Living organisms
• - provide a longer-term view
• - are continuous monitors they integrate
  effects of time and multiple pollutants
• - can be cheap and easy to assess
• - can be used for different purposes
• - account for synergistic (magnifying) and
  antagonistic (reducing) effects (e.g. pH)

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Where does ecotoxicology fit in?

• The study of the effects of toxic substances on
  aquatic organisms
• usually laboratory-based experiments
• link between WQ and its effects on the biota
  e.g. used for deriving guidelines
• includes field studies
• bioaccumulation / biomagnification active
  biomonitoring
• use of biomarkers

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Which organisms to use in bioassessment?
Protozoa /diatoms identification
specialised Algae / periphyton Macroinvertebrates
Fish Macrophytes Birds
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• First ask,
• WHAT DO WE WANT THE
• BIOTA TO TELL US??
• i.e. what are we monitoring FOR?

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• e.g. it can provide a measure of change
• We can monitor specific features, usually at
  fixed points
• e.g. edges between veg. types water
  level degree of sedimentation fixed-point
  photography geomorphology of
  channels density of aliens aspects of
  ground water

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• Individual species as indicator species
• e.g. halophytes halophobes tolerators of
  low pH
• rapid responders to changes in nutrient
  levels those whose eggs must
  desiccate before hatching ruderal
  species

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• Can use assemblages
• e.g. diatoms (good for aspects of water
  chemistry)
• odonates (IBI?)
• molluscs (IBI?)
• macrophytes (hydroperiod / water level)
• macro-invertebrates (generalized
  impairment of water quality)

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• What criteria are important when selecting
  techniques / indicators?
• - rapidity ( therefore cost)
• - narrowness of tolerance ranges
• - common-ness (or even rarity)
• - ease of identification
• - life cycle of the right length

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• What methods of analysis?
• What taxonomic level of identification?
• What numerical methods
• simple arithmetic (e.g. SASS)?
• multivariate analyses (e.g. AusRivas,
  Rivpacs) predictive modelling?
• Validation of proposed indices?
• What level of confidence is necessary?

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• What can biomonitoring NOT do??
• It cannot replace phys chem. data (it
  complements it)
• It does not explain the cause of the problem,
  merely indicates that there is one
• It seldom predicts outcomes (but indicates
  trajectory of change).

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THE NATIONAL WETLAND RESEARCH PROGRAMME

• PHASE II WETLAND HEALTH AND INTEGRITY

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Development of the WHI research programme

• Strategic overview of research needs in wetlands
• Malan and Day (2005) Strategic overview of the
  research needs for wetland health and integrity.
  WRC Report no. KV 171/05.
• Malan, Day Marr (2005) Assessment of wetland
  ecological health and socio-economic importance
  an annotated bibliography. WRC Report no. KV
  172/05

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Aims of the WHI research programme

• To develop tools for assessing
• - ecological condition
• - aspects of the biophysical environment (e.g.
  water quality, hydroperiod)
• - socio-economic importance
• - loss of wetland function through degradation

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THE INDIVIDUAL PROJECTS
DIATOM INDEX Development of an index based on
diatoms - commonly used for aspects of water
chemistry
MACROPHYTE INDEX Development of an index of
biotic integrity / ecosystem condition based on
macrophytes - consolidation of plant species
lists individual species as indicators of
specific conditions (e.g. high salinity or low
pH)
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• INVERTEBRATE INDEX
• To investigate the feasibility of developing an
  index of wetland health using invertebrates
• - PhD project

DRY CONDITION INDEX - identification of
non-perennial wetlands - assessment of their
condition / integrity in the dry state Use of
macrophytes? invertebrates? diatoms?
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TESTING OF EXISTING TOOLS critique/gap
analysis - WET-EcoServices (index of
functionality) rapid evaluation of wetland
goods services - WET-Health (a type of
IBI) - Ecological Importance and
Sensitivity (to be used by DWAF)
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DEPENDENCY METRIC Development of a metric of
socio-economic dependency of communities on a
wetland SUSTAINABILITY METRICS effect of
human use on - ecosystem functionality - sustai
nability use of a wetland
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LOSS-OF-FUNCTION METRIC Relationship between
function and extent of degradation
LANDSCAPE-LEVEL IMPACTS The cumulative impact of
wetland loss at the landscape level
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