The risks of alien plant invasions to land owners in the Garden Route
Upcoming SlideShare
Loading in...5
×
 

The risks of alien plant invasions to land owners in the Garden Route

on

  • 295 views

Presentation by Christo Fabricius to the South Cape Land Owners Iniative

Presentation by Christo Fabricius to the South Cape Land Owners Iniative

Statistics

Views

Total Views
295
Views on SlideShare
295
Embed Views
0

Actions

Likes
0
Downloads
2
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Adobe PDF

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

The risks of alien plant invasions to land owners in the Garden Route The risks of alien plant invasions to land owners in the Garden Route Presentation Transcript

  • Risks of alien plant infestations to land owners Christo Fabricius
  • National Invasive Alien Plant Survey Initial clearing = 48 years/R52 billion 1. 2. 3. 4. 5. Acacia mearnsii, A. dealbata & A. decurrens Eucalyptus spp. Pinus spp. Opuntia spp. Salix spp. Economic impact = R13 billion/annum 8% 51% 5% 39% 20% 8% 22% 1% 16% 9% (Kotze et al., 2010) 20%
  • Pines invading the watersheds of the Western Cape
  • If we do not clear invasive alien plants …
  • Nitrogen Fuel load Soil loss levels after fire Stream flow Infested Not infested Infested Crop yields Carrying capacity Not infested
  • Negative impacts on agriculture • More evaporation – Reduced stream flow – Less water = higher concentrations of polluting nutrients • • • • Reduced ground water quantity, quality More intense fires Increased soil erosion Serious water quality and quantity problems
  • YIELD per Hectare Profitable Unprofitable COSTS (Chemicals; fuel; labour; ALIEN PLANT MANAGEMENT)
  • 4. Biological Control For many invading species, in many parts of the world, it is the only hope. Melanterius weevil on Acacia cyclops Species Red sesbania Benefit :cost ratio 45 : 1 Lantana Long-leaved wattle 34 : 1 1 465 : 1 Golden wattle 4 333 : 1 Silky hakea 611 : 1