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