EARTH SCIENCES
Annual Review 2012
Highlights and IssuesP.D. McIntosh
Staff
Geoscientist Adrian Slee resigned during the year. Adrian began a PhD at the
University of Queensland. He continues to participate in the research he initiated in
the Florentine (with Norske Skog) and near Mt Nicholas.
Advice
Earth sciences notifications from State
and private forest, 2012–13
Advice provided, office assessment
Advice provided, field assessment
Total notifications
State forest 73 (119) 24 (57) 97 (176)
Private forest 62 (73) 31 (44) 93 (117)
Total 135 (192) 55 (101) 190 (293)
Strahan harvest - windthrow
Pine harvest is
‘on hold’
Windthrow into a
Class 1 stream is
a problem.
Options:
• leave ‘as is’
• burn
• cable harvest
• hand-release
and excavator
removal
Option 4 selected – heavy excavator with a long reach floated to site by FT
Chainsaw
operator
Stream
Excavator
Same stream bend after salvage harvest – riparian areas will be replanted with native species
Photo: Clive Woolridge
Debris has been stacked 10 m away from streams
FPA will continue to monitor patches of windthrow occurring
in remaining standing forest
Plantations of northeast Tasmaniagood progress in revegetation 2007-2012
Problems still occurring during high rainfall events
Scamander February 2011
Fingal Management Strategy has been revised
Advantages:•Timelines so that FPA can see what is happeningin whole catchments
•Revegetation progress can be easily monitored
Long-term aim:A multi-age plantation with a patchwork of native forest and stable streams and riparian areas.
Guidelines were endorsed by FPAC and the Board in the past year and have been generally applied
Guideline development
Research and Monitoring
Three major projects (FPA lead researcher):
• Effect of pine harvest on karst development (sinkholes) in the Florentine Valley
• Erosion history in the forest estate
• Mass movement episodes and landslide risk in dolerite terrain in northeast Tasmania
One minor project (FPA assisting):
• Age of grasslands on Gunn’s Surrey Hills estate
Effect of pine harvest on karst development
(sinkholes) in the Florentine ValleyAim
Do wetter ground conditions after pine
harvest cause sinkholes to collapse?
Project partners
Norske Skog
Kevin Williamsof
Norske Skog mapping the
perimeter of a large sinkhole
Monitor every year
Erosion history in the forest estateAims(1) To find out when landscape instability occurred, as a guide to present risk(2) To record important Quaternary geoconservation sites that may be important for assessing past climates and palaeoecology
Dune on Southwood Road dated 19000 years old
Paper has been accepted by
the international journal
Geomorphology
Project partners: Universities of Wollongong, Queensland, Tasmania
Risks – Strahan
•Active Henty Dunes - winds from the west
•The E-W dunes formed by winds from the north –10,000 years ago
•There is little chance of sustained winds from this direction at present
•Pine plantation may be re-established – taking care to preserve landforms
Site will be proposed for listing in the Tasmanian GeoconservationDatabase for its geological and palaeoclimate importance
Landslides on Mt Nicholas
Mt Nicholas
55 000 years
Supervisors course, Tyenna• soil identification• high erodibility soils• collapsing road batters• cultivation policy in wet areas • Class 4 stream guidelines
Training
Applying Road
Batter Guidelines
(FT Murchison)
Class 4 stream course (FT Murchison)
Commercial
work
Assessing soil erodibility on a
subdivision on Flinders Island
Characterisation of soils at the
Warra carbon Flux Tower site
Future
• Review of progress on catchment approach in
plantations
• Reassess sites in Florentine karst project
• Two scientific papers to complete
• Seek further commercial work and inter-agency
links (Universities, NRM groups)
• Giving advice to foresters
on best practice