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Weed risk assessment and control

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					Weed risk assessment and
         control




Peter Williams, Mark Lewis, Alan Hastings, Rua Murray, Miranda
Bennett, Jeff Diez, Ian Westbrooke, Rohan, Tanya Soboleva,
Kyoko Fukuda, Ben Perdriau
          Risk assessment
• Legally introduced species are assessed
  for “weediness” before being allowed into
  NZ
• Some accidentally/illegally introduced
• Many already present
• Would like a method for quick assessment
  of weeds already introduced
• Need info on cases of good plants turned
  bad
                    Control
• Control effort focussed on relatively small
  number of invasive species
• RCs reluctant to add new species to
  strategy
• But what about currently introduced
  (30000) and naturalised (3000) species
  that may be future pests?

       Introduced    Wild       Pest
       30000         3000       300
• 3 categories
  of exotic
  species
• Transition
  between
  categories
• Limited
  control effort
• Optimisation
  problem for
  allocation of
  control effort
• Minimise present
  cost over finite
  time horizon
• Linear -> “All
  eggs in one
  basket”
• Nonlinear??
  Pests can be divided into further
            categories
• Different species (or class of species)
• Different regions
• RC categories: total control (eradication),
  surveillance (banned from sale),
  containment.
              Still to do…
• Data on cost/damage of having species in
  each category
• Include amount of spead?
• Risk of transition between classes?
• Maximum (and minimum?) effort for each
  class (or more realistic nonlinear control
  efficacy)?
• Solve it!

				
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posted:7/5/2013
language:English
pages:7
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