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					Biodiversity information revelation
    and assessment process


             David Parkes
 Dept. of Sustainability & Environment
                Victoria
• 58% of Victoria has been cleared
     • 63% of Victoria is private land
      of which about 93% has been cleared
           • alienation and associated clearing
           has been highly selective
             Policy Context
• reverse the decline in the extent and
  quality of native vegetation and habitat,
  leading to a net gain
                       Victoria‟s Native Vegetation Management
                                   - A Framework for Action 2002

to be achieved in the context of other goals
• maintain and recover biodiversity
• maintain and recover catchment values
• Ecologically Sustainable Development
• community capacity
       Reversal of long-term decline in extent & quality
          of native vegetation leading to Net Gain
     LOSSES                   LOSSES & GAINS           GAINS
                                “balanced”
                                                     voluntary &
clearing allowed             natural disturbance   Govt-assisted
 by exemption                     • wildfires      management &
                                                    revegetation
                              harvest & regen.
 loss of quality                                   on public land
• permitted uses              clearing by permit   on private land
• pest plants & animals        & related offsets
• intensive fuel reduction
• ongoing tree decline
                                                    BushTender
  illegal clearing
     Influencing biodiversity management
            is a continuing challenge
 inherently diverse and complex
    - 100‟s of major ecosystems
    - 1000‟s of species (higher plants & animals)
    - untold genetic diversity                       CHAOS!
 across all tenures and land uses
    - 1000‟s of land managers
 limited awareness, scientific knowledge and investment

=> approaches must be sound but very pragmatic
     - strong DSE focus on vegetation information
    (location, type, cons. status, condition, use by species)
   Traditional information relationships
  BIODIVERSITY                      THREATS
                                 clearing, harvesting,
  SIGNIFICANCE
                                inappropriate grazing /
endangered, vulnerable,            fire / flood regimes,
    depleted, rare                pest plants & animals



 BIODIVERSITY ASSETS
 species, ecosystems, naturalness

                                       MANAGEMENT
           protection by
          RESERVATION
   Traditional information relationships
  BIODIVERSITY                      THREATS
                                 clearing, harvesting,
  SIGNIFICANCE
                                inappropriate grazing /
endangered, vulnerable,            fire / flood regimes,
    depleted, rare                pest plants & animals



 BIODIVERSITY ASSETS
 species, ecosystems, naturalness

                                       MANAGEMENT
           protection by
          RESERVATION
 Changing information relationships
                CONDITION                   THREATS
             current habitat service

BIODIVERSITY
                                 MGT. OUTCOME
SIGNIFICANCE
                                       “AMOUNT OF
   “VALUE”
                                         CHANGE”



     BIODIVERSITY ASSETS
     species, ecosystems, naturalness

                                        MANAGEMENT
  Desirable characteristics of an approach
       to native vegetation condition
                   • degree of “naturalness”

                    • indicate options for
                        improvement
science



            !?       • compare between




                                                       NRM
                      different vegn types

          !? •     combine quality & quantity
                  to calculate net outcomes
                 • objective / reliable / repeatable

                    • non-specialist / rapid
             •     deliver a practical message
         Vegetation / Habitat Condition

 one Habitat Hectare =
   one hectare of native vegetation which retains
  the average characteristics of a mature and
  apparently long-undisturbed stand of the same
  vegetation type
• requires a reference point or “benchmark” for each
  vegetation type which encompasses the full range of
  condition states of interest to NRM
• vegetation types are Ecological Vegetation Classes
  described by bioregions (over 1000 in Victoria)
                 Habitat Score

Large Trees              DBH for EVC / genus
                         no. / ha + “health”
Tree Canopy Cover        >80% mature height
                         proj. foliage cover + “health”
Understorey              presence of expected lifeforms,
                           then diversity & cover
Lack of Weeds            cover and threat rating
Regeneration             expected given recruitment
                            strategy?
                         “adequate” to replace current?
Organic Litter           cover
Logs                     length
Patch Size               vegetation contiguous to site
Neighbourhood            within radii of site
Distance to Core Area    closeness to >50 ha area
                 Habitat Score
                 Component                    Max. Value
                                                 (%)
                 Large Trees *                    10
                 Tree Canopy Cover *              5
                 Understorey                      25
 'Site           Lack of Weeds                    15
 Condition'      Regeneration (woody)             10
 Component       Organic Litter                   5
                 Logs *                           5
 'Landscape      Patch Size                        10
 Context'        Neighbourhood                     10
 Component       Distance to Core Area              5
                 Total                             100

* excluded for non-woody vegetation types, then score standardised
Undisturbed vegetation




              Habitat score = 0.90
Reduced quality of vegetation in cleared landscapes



     reduced cover
        of trees



                                          reduced
                                        recruitment




    reduced
  understorey                     increased cover
   diversity                         of weeds


                             Habitat score = 0.50
Reduced quality of vegetation in cleared landscapes
                                       greatly reduced
                                        vegetation in
                                          landscape




                                       only relict trees



 increased cover
    of weeds
 greatly reduced
   understorey
    diversity

                             Habitat score = 0.25
Based on currently observable features of site.

Does not include risk (impact, likelihood, recoverability)
related to:
   • pest animals
   • conflicting adjacent land use
        (e.g. ag.chemicals, drainage)
   • broad-scale issues
        (e.g. salinity, climate change)
This risk needs to be based on modelling at
the landscape scale.
   Habitat Score - further development
• missing features? (e.g. hollows)
• additional “hard to assess” components?
  (e.g. soil health)
• different weightings / index formula?

• application to revegetation
• application to fluctuating environments
  (e.g. wetlands)

• review after two years of use / research
• stimulated similar development in NSW, Tas, Qld, SA, WA
Vegetation condition – how full is the glass?
                       full and stable




        benchmark



          current
         condition
Vegetation condition – how full is the glass?
    emptied by catastrophic disturbance event




         benchmark



           current
          condition


      catastrophic
      disturbance
Vegetation condition – how full is the glass?
    recovery from catastrophic disturbance event


                      regenerative
                       processes

        benchmark



          current
         condition
Vegetation condition – how full is the glass?
              surviving a “drought” event


                      regenerative
                       processes

        benchmark



          current
         condition
Vegetation condition – how full is the glass?
                     sustainable use?


                      regenerative
                       processes

        benchmark



          current
         condition              degenerative
                                 processes
Vegetation condition – how full is the glass?
 recovery limited by damage to regenerative processes?



                       regenerative
                        processes

         benchmark


      alternative
      state limit?
                                 degenerative
         current                  processes
        condition
Vegetation condition – how full is the glass?
                     unsustainable use


                      regenerative
                       processes

        benchmark



          current
         condition              degenerative
                                 processes
 Vegetation condition – how full is the glass?
               snap-shot estimate of trajectory


              regenerative
               processes                     What is the
                                           net outcome of
 benchmark                               current processes?

                                          What management
                                          options can make
   current                                 the net outcome
  condition             degenerative        more positive?
                         processes



1. Current?    2. Prognosis?           3. Intervention?
 Applications of habitat hectares

• predicting changes at site following
  changed management
• calculating losses & gains as part of
  mitigating clearing
• improving investment decisions
• reporting overall progress
 BushTender information relationships
                      CONDITION                      THREATS
                  current habitat service

  BIODIVERSITY
                                           MGT. OUTCOME
  SIGNIFICANCE
                                          action to secure and/or
  conservation status
endangered, vulnerable,
                                          improve habitat service
     depleted, rare
   landscape priority


   BIODIVERSITY BENEFIT                          MANAGEMENT
   (significance X mgt. outcome) / cost

                                                      COST
Key questions for
individual investment decisions:
what is our level of interest in intervening?
                          “the right potential”

 how much difference would an action make?
                        “the right actions”

 what is a reasonable amount to invest in an action?
                            “the right cost”

   will someone undertake the action?
                                “the right terms”
            how do we bring „all of the above‟ together?
                                      “the right choices”
Key questions for
individual investment decisions:
what is our level of interest in intervening?
       “the right potential” SIGNIFICANCE MEASURE

how much difference would an action make?
     “the right actions” SERVICE MEASURE

 what is a reasonable amount to invest in an action?
        “the right cost”  COMPARATIVE DOLLARS

  will someone undertake the action?
        “the right terms” PARTICIPATION / COMPLIANCE
         how do we bring „all of the above‟ together?
                  “the right choices” BENEFITS INDEX
An index must combine several interactive measures
(each being variable & conceptually complex).
An index allow explicit calculations based
on controlled combinations of the factors.
 (even the most capable people can’t do this in their head!)

.but remember, measures & indices are just models,
       ( “all models are wrong, but some are useful” )
        and must be constructed and used mindfully
          ( “players give up something to gain something” )
      Information characteristics
SERVICE MEASURE
 Outcome-driven estimate of “change in level
  of function” based on available science
  (i.e. better thought of as a ”currency”
           than a ”preference”)
A 4-dimensional unit:
• change in quality
• quantity (area : 2-d)
• time
                         Scoring gains
     A standard period (10 years) is used to estimate gains
     from changed management of vegetation
       1
                                              potential
                                              improvement




                                                                            Habitat Gain
habitat                                       gain (typically 0.05- 0.15)
score                                             +
                                              potential
                                              maintenance
                                              gain (typically 0.05- 0.1)

          0                           10 yr
   low starting score (e.g. revegetation) => mostly improvement gain
   high starting score (e.g. long undisturbed) => mostly maintenance gain
      Information characteristics
SIGNIFICANCE MEASURE
 predominantly a value-driven consensus
 based on science & policy
  (i.e. a “preference”)
combines:
• no. & cons. status of species (capped)
• cons. status of vegn. types
• site condition
• Landscape preference
      Landscape Preference Score
• applying rules to GIS datasets based on best-
  estimates of ecological drivers for major
  vegetation types and associated species
  assemblages
• resilience / recovery “logic”
  broad scale
  e.g. balance of reveg. vs remnant protection
  fine scale
  e.g. area thresholds?, buffering, linkage
• ? Risks: e.g. salinity (negative)
                  or likelihood of synergies (positive)
    intact      variegated      fragmented          relict




reveg. is advantaged by surrounding veg.


                          reveg. is required to restore function

                    reveg. will have optimal benefit
Remnant Vegetation   Buffer/Linkage




                              X




                                          Landscape
                                          Preference

Landscape Context    Spatial Preference
        Biodiversity Benefits Index
                                       selection of bids
 current
 Biodiversity
 Significance
 Score                            landholders discretion




                Habitat Services Score / $$


• used for objective discrimination between bidders
  based on conservation preference, price and habitat
  services being offered
• “value for money” measure for biodiversity conservation
                      Results for
Significance   Northern Victoria trial area
Biodiversity




               Habitat Service / $
                Supply curve of "biodiversity gains"

  40
  35
  30
  25
$ 20
  15
  10
   5
   0
       0     200,000   400,000   600,000   800,000   1,000,000 1,200,000 1,400,000
           cumulative "Biodiversity Gain" units (significance X service)
 Benefits Index                     Results for
  threshold for
available budget
                             Northern Victoria trial area
                                                                 best value
                                    (higher sign. / good service / lower cost)
 Significance
 Biodiversity




least value
                            Habitat Service / $
                unsuccessful bids                 successful bids
On-site outcomes for habitat

                         Increased
                         habitat
     On-site outcomes for multiple
       environmental attributes

                                          Increased
                                          habitat


                                          Increased
     Reduced                              carbon
     nutrient / soil
     movement


BushTender, CarbonTender, PlainsTender, RiverTender
On-site and off-site outcomes for
multiple environmental attributes
     Off-site
     outcome
     change                  On-site
                             outcome
                             change
     - surface               - habitat
       water
                             - carbon
                             - water
     - sub-surface
       water
Biodiversity information revelation
    and assessment process


             David Parkes
 Dept. of Sustainability & Environment
                Victoria

				
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