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Overview of vegetation management – VAST as a solution. Presentation given to Australian Defence Force Academy students on 28 August 2012.
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Overview of vegetation management – VAST as a solution
Richard Thackway
Lecture presented to ADFA Geography students, Canberra on 28 August 2012School of Physical, Environmental and Mathematical Sciences, University of New South Wales
Outline
• Perceptions• Definitions• Land management and vegetation• Effects of managing native vegetation • Reporting change in the condition of vegetation
types• Reporting the transformation of plant communities• Importance of collecting information
• Diverse and healthy native vegetation is important• My vegetation is in good condition • My water is my asset• My soil is my asset • My animals are my asset• Vegetation is a means to an end – utilitarian • I want to hand my land in good condition to my children
/future generations
Some perceptions of land managers (public and private)
What is vegetation use and management?
• Land use determines primary purpose for land cover types e.g.– Forestry is typified by forest veg cover types– Cropping is typified by annual veg cover types– Urban is typified by infrastructure cover types– Water harvesting is typified by many veg cover types – Defence training is typified by native veg cover types
• Land management practices (LMP) = the how of land use
What are management practices?
• Remove life form/s &/or species e.g. tree, shrub, grass– e.g. push out, pull out, cut off and chemically treat
• Replace life form/s &/or species e.g. tree, shrub, grass– e.g. replant, rehabilitate, re-sow
• Manage health & vitality of life form/s &/or species e.g. tree, shrub, grass– e.g. prune, stake, slash, fertilise, graze
• Manage residues from life form/s &/or species e.g. tree, shrub, grass – e.g. burn grass, burn fine woody debris, bark, leaves
What is vegetation condition?
• Vegetation condition is relative concept• Context dependant
– Same patch can be assessed differently for purposes
• Analogous to human health and the ‘norm’
Natural vegetation and the environment
• Environmental patterns and processes– Environmental gradients – Climate influencers
• Cycles - seasons, annual and decadal events – Dust, fires, cyclones, flood, drought, insects, pathogens
– Interactions with other physical influencers • Landform, relief, aspect, geology, soil, hydrology
• Observed drives veg patterns and processes– Productivity– Maintaining life cycles – reproduction, germination, establishment,
growth, and death– Succession– Responses to perturbations and disturbances – Species, communities and ecosystems
Goals of land managers
Change ecological function
Values and decisions matrix:• Social• Economic• Environmental
Intensification
Degradation?
Goals of land managers
Change ecological function
Values and decisions matrix:• Social• Economic• Environmental
Extensification
Restoration
Regulation of hydrological regime Generation of food and fibre Regulation of climate / microclimate Generation of raw materials Recycling of organic matter Creating and regulating habitats Controlling reproduction and dispersal
Changing ecological function to derive multiple benefits (ecosystem services)
How is vegetation condition info is used in decision making?
1. Characterise status & trends/ identify problems with resource condition and /or assets
– What, where, when, why & who
2. Assist in setting goals, objectives, priorities, targets3. Design & implement program/s
– e.g. MBIs, regulation, education, investment, interventions, etc
4. Check on performance of on-ground of investment– e.g. Was the target met? Did land management change?
5. Report again on resource condition Adaptive management
cycle
1
5
43
2
Vegetation management & condition What do land managers modify / replace/ remove?
– Vegetation structure • Life form (tree:grass)• Growth stage /Age class• Height• Cover/density• Strata/layers/complexity
– Species composition• Richness or number of species• Evenness of individuals per
species • Functional traits
– Regenerative capacity • Fire regime • Soil structure• Soil hydrology• Soil structure• Soil nutrients• Reproductive potential
Natural vegetation and land use
• Land use and vegetation– Single use– Multiple uses
• Intensification of land use – Minimal = Nature conservation, Defence training areas– Moderate = Pulse grazing, Selective logging forestry– High = Continuous or set stock grazing – Very high = Plantations, Cropping, Bomb target areas– Extreme = Water impoundments, Built infrastructure
Species Composition
Growth Form
% Foliage Cover
Height
U
M
G
NVIS Data Model
Natural vegetation for nature conservation
Species Composition
Growth Form
% Foliage Cover
Height
U
M
G
NVIS Data Model
Natural vegetation for defence training
Species Composition
Growth Form
% Foliage Cover
Height
U
M
G
NVIS Data Model
Land management for grazing
Species Composition
Growth Form
% Foliage Cover
Height
U
NVIS Data Model
Land management for plantation forestry
How to report vegetation management at different scales?
• Site modification of plant communities– species composition– Vegetation structure– Regenerative capacity
• Landscape levels– Patchiness – Fragmentation and connectivity
Vegetation States Assets and Transitions (VAST) framework
VIVIVIIIIII0
Native vegetationcover
Non-native vegetationcover
Increasing vegetation modification
Transitions = trend
Vegetation thresholds
Benchmark for each veg type (NVIS)
VAST a framework – linking land management and native veg condition
Condition states
ResidualNaturally bare
Modified Transformed Replaced -Adventive
Replaced - managed
Replaced - removed
Modification
Frag
men
tatio
n
Conceptual framework for understanding vegetation condition and landscape
change
Intact
>90%
Variegated
60-90% retained
Fragmented
10-60% retained
Relictual
<10% retained
Native
Unmodified
Modified and retained
Highly modified
Destroyed
VAST I ResidualVAST 0 Naturally Bare
VAST II Modified
VAST III Transformed
VAST IV Replaced – Adventive, VAST V Replaced – Managed VAST VI Removed
Intensification
Extensifi
cation
McIntyre and Hobbs 1999
p142-02
p142-18
p143
Monitoring & reporting at sites - poplar box woodlands (Central Qld)VAST I • Freehold no grazing• Multiple strata, some emergents• Biomass ~120 t/ha • FPC ~ 52%, Max height ~ 24m• Spp OverS 3-5, MidS 5+, GroundS 5-10• Regen - good
VAST II • Freehold - grazing • Two strata• Biomass ~68 t/ha • FPC ~ 25%, Max height ~ 17m• Spp OverS 3, MidS 1, GroundS ~1-4• Regen – Low-Moderate
VAST III • Freehold - heavy grazing - mechanical thinning• Single, low height strata • Biomass ~42 t/ha • FPC ~ 20%, Max height ~ 13m• Spp OverS 3, MidS 0, GroundS ~1-4• Regen – very low, > % bare ground
Vegetation condition – a snapshot
Thackway & Lesslie (2008) Environmental Management, 42, 572-90
Landscape alteration levels – a snapshot
LALs derived using a 2.5 kmInput VAST national 1 km
0
10
20
30
40
50
60
70
80
90
100
Intact Variegated Fragmented RelictualLandscape Alteration Level
Ave
rag
e P
rop
ort
ion
(%
) o
f V
AS
T C
on
dit
ion
Sta
te
Residual*
Modified
Transformed
Managed
Removed
Mutendeudzi and ThackwayBRS 2010
VAST Classes
Regional reporting of change in vegetation type and condition using VAST
IBRA subregions - Major Vegetation Groups - Vegetation Assets States Transitions
0.00%
20.00%
40.00%
60.00%
80.00%
100.00%
120.00%
Acaciashrublands
Casuarinaforests andwoodlands
Chenopodshrublands,samphire
shrubs andforblan
Eucalyptusopen
woodlands
Eucalyptuswoodlands
Heath Low closedforest andtall closedshrubland
Malleewoodlands
andshrublands
Othershrublands
#N/A
Major Vegetation Groups
6 Removed
5 Replaced Native
3 Transformed
2 Modified
1 Residual
0 Residual Bare
IBRAS_D Avon Wheatbelt - Avon Wheatbelt P1
Sum of COUNT
MVG_D
VAST_D
Sub-IBRA & MVG & VAST (1km)
A system for scoring effects of management over time relative to a reference states for indicators of vegetation condition
ACT, Belconnen Naval Transmission Station
Illustrating 10 of 22 indicators
VASTTRANS
VASTTRANS uses the historical record to track the effects of managing native vegetation
• Site modification of plant communities– species composition– Vegetation structure– Regenerative capacity
• History of use and management – Minimal = unmodified native veg & land cover– Moderate = modified native veg & land cover– High = transformed native veg & land cover– Very high = replace native veg & land cover– Extreme = remove native veg & land cover
Approximate year
Source: Year
LU & LMP Source: LU & LMP
Effects of use and management on vegetation condition and
ecological function
Source: Effects
1800
1840
2010
VASTTRANS - compiling the historical record
Pre-contact
First contact
Current year
LU = Land Use, LMP = Land Management Practices
1
3
10
22
VAST
D
iagn
ostic
attrib
utesVegetation
Transformationscore
Attrib
ute
grou
ps
VegetationStructure
Overstorey
(3)
Understorey
(3)
SpeciesComposition
(2)
UnderstoreyOverstorey
(2)
RegenerativeCapacity
Fire
(2)
Reprodpotent
(2)
Soil
Hydrology
(2)
Biology
(2)
Chemistry
(2)
Structure
(2) Indicators
Indicators affected by managing native vegetation
RC_fire_burnt_area RC_soil_hyd_surf_water RC_soil_biol_organ_matt
RC_reprod_potent_OS RC_reprod_potent_US
VS_OS_height VS_OS_fpc VS_OS_div_age_class
SC_US_fnl_groups SC_US_richness
1
3
10
22
Dia
gnos
ticatt
ribut
es
VegetationTransformation
score
Attrib
ute
grou
ps
VegetationStructure
Overstorey
(3)
Understorey
(3)
SpeciesComposition
(2)
UnderstoreyOverstorey
(2)
RegenerativeCapacity
Fire
(2)
Reprodpotent
(2)
Soil
Hydrology
(2)
Biology
(2)
Chemistry
(2)
Structure
(2) Indicators
Putting it together to tell a story
1750 1800 1850 1900 1950 2000 20500
10
20
30
40
50
60
70
80
90
100
Belconnen Naval Transmitter StationRegenerative CapacityVegetation StructureSpecies CompositionVegetation status
year
scor
e (%
)
1750 1800 1850 1900 1950 2000 20500
10
20
30
40
50
60
70
80
90
100
Belconnen Naval Transmitter StationRegenerative CapacityVegetation StructureSpecies CompositionVegetation status
year
scor
e (%
)
Sheep grazing commenced
Commenced continuous sheep grazing
Sheep grazing ceased
Limited management by Ngunnawal people
Kangaroo population culled
Kangaroo population increasing
Woodland trees ringbarked
Grass mowing started and stopped
NSW, Big Scrub, Rocky Creek Dam Reference pre-European Complex Notophyll Vine Forest
Unmodified and intact
Clearing and conversion to pasture
Start of grazing exotic pasture
End grazing pastures
Removal of weeds Lantana - Privet
Commenced monitoring of regeneration
VAST classes
25 ha of dense Lantana
NSW, NC Bioregion, ‘Tintenbar’Reference pre-European Complex Notophyll Vine Forest
Unmodified and intact rainforest
Clearing and conversion
Start of grazing exotic pasture
End of grazing pastures
Rainforest seedlings under dense Camphor forest
Start of ploughing & cropping
VAST classes
28 ha of dense Camphor laurel forest
Source: John Ive 2006
‘Talaheni’ 250 ha property near Murrumbateman, NSW
1962 1983 1986 1997 2004
Reporting VASTTRANS using VAST classes
‘Talaheni’ 250 ha property near Murrumbateman, NSW
Reporting VAST condition states ‘Talaheni’
0
50
100
150
200
250
300
1962 1983 1986 1997 2004
Year of VAST assessment
hecta
res
2
31
32
33
5
6
Hectares
• Land managers play a major role in transforming native vegetation types
• Arguably land managers should record their management actions and key observed effects for adaptive management +++
• Understanding the effects of use and management of native vegetation can be retrofitted to a historic record of management
• VAST is a tool for reporting modification of veg condition across land uses as status reports at a range of scales
• VASTTRANS is a tool for tracking the transformation of plant communities caused by use and management practices
Conclusions
Acknowledgements
Many people have helped in developing VAST including staff from SEWPAC, DAFF, ABARES, state and territory agencies, CSIRO, Greening Australia and regional bodies