Managing vegetation for multiple benefit outcomes –

Diagnosis and Prognosis

Richard Thackway

Presentation to Murray Darling Basin Authority22 September 2016

MDBA has identified two development areas for native vegetation:

1. Analysis framework for evaluation of extent and condition of woody vegetation communities

2. Developing scenarios for future landscape transformation

Definitions

• Change in a plant community (type) due to effects of land management practices:

– Structure

– Composition

– Regenerative capacity• Resilience = the capacity of an plant community to recover to

a reference state following a change/s in land management

• Transformation = changes to vegetation condition over time• Condition, resilience and transformation are assessed relative

to fully natural a reference state

Vegetation condition

VAST = Vegetation Assets States and TransitionsNVIS = National Vegetation Information System

VIVIVIIIIII0

Native vegetationcover

Non-native vegetationcover

Increasing modification caused by use and management

Transitions = trend

Vegetation thresholds

Reference for each veg type (NVIS)

A framework for assessing modification of native vegetation extent and condition

Condition states

Residual or unmodified

Naturally bare

Modified Transformed Replaced -Adventive

Replaced - managed

Replaced - removed

Thackway & Lesslie (2008)

Diagnostic attributes of VAST (classes):• Vegetation structure• Species composition• Regenerative capacity

VAST-2 criteria and indicators Change & Trend

NVIS

1925

Occupation

Relaxation

Anthropogenic change

Net benefit

time

1900 2025 1950

Reference

chan

ge in

veg

etati

on in

dica

tor o

r ind

ex

1850 1875 1975 2000

Model of ecosystem change (causes & effects)

Baseline

Accounting for changes in native veg type, extent and condition

Land managers use LMP to influence ecological function at sites and across landscapes by changing:• Vegetation structure• Species composition and • Regenerative capacity

LMP deliberately &/or unintentionally do this by:• Modifying • Removing and replacing• Enhancing• Restoring• Maintaining• Improving

*

* Natural disturbances

Function

Structure & Composition

LMP = land management practices

Goal is to develop whole of landscape monitoring of criteria and indicators relative to reference states

0

20

40

60

80

100

1985 1990 1995 2000 2005 2010

Year

FPC

Source: Tim Danaher and Phil Tickle

Site and landscape scales

1925

Occupation

Relaxation

Anthropogenic change

Net benefit

time

1900 2025 1950

Reference

chan

ge in

veg

etati

on in

dica

tor o

r ind

ex

1850 1875 1975 2000

VAST classes

Evaluation of ecosystem change thatrely on remote sensing metrics however …

Hyperspatial, hypertemoral &

hyperspectral remote sensing

Aerial photos and digital

imagery

Aerial photos

Quantitative

Baseline

Time before remote sensing

Caution - remote sensing change is relative to a baseline - it is only half the answer – NEED REFERENCE STATE

Zero/constant baseline (e.g. environmental planting = reveg)

Resp

onse

va

riabl

e/s

Time

Start ofactivity/

intervention

Time

Varying baseline (e.g. environmental watering)

Resp

onse

va

riabl

e/s

Single intervention & climatic variability

BaselineResponse to activity/ intervention

Indicator 13: Overstorey height

Indicator 4: ground water

Photo by Peter Coyne

1740

1906

Phillip Island, South Pacific – extent and condition

Photo State Library NSW: JW Beattie

1860 already denuded

year

scor

e %

Pine – Hardwood Subtropical Rainforest, Phillip Island, Sth Pac

Pigs released

Uninhabited island

Pigs died out

Goats, rabbit and fowl released

Goats died out

Rabbits eradicated

Rabbit control

commenced

Commenced passive & active

restoration. Minimal ecological

monitoring

Phase 1 Phase 2 Phase 3 Phase 4

Evaluation framework

• Has been extensively used to evaluate condition outcomes – Diagnosing and reporting condition (i.e. status and trend) of veget

ation types – Evaluating examples of restoration and regeneration

Tran

sfor

mat

ion

scor

e

Years

1800

2016

Reference

Developing scenarios for future landscape transformation

Modified

Transformed

Replaced/ managed

Residual

Replaced/adventive

VAST Classes

1850 19501900 2000 2050 2100Replaced/ removed

Baseline

Classes can be modelled as extent and condition

Extent native

NSW, SB Bioregion, Cumberland SF, Transect 2 (ex-comp 3a, 7a, 7b, 7c)Reference pre-European: Sydney Blue Gum High Forest

Commenced managing area for recreation. Weed control. Arboretum abandoned

Cleared & sown to improved pasture for grazing & orchard

Commenced grazing native pastures

Indigenous people manage the area

Grazed area gazetted as State Forest, commenced planting arboretum

Area logged for building houses and fences

Commenced managing area as a future production forest. Weed control

Explorers traverse the area and site selected

Ceased grazing. Area purchased as a future working forest

Modified

Transformed

Replaced/ managed or removed

Residual

Replaced /adventive

VAST

Before developing any scenarios it is critical to assess where, when and how landscapes were/are transformed relative to a reference

Spp compVeg structure

LU = Land Use, LMP = Land Management Practices

VAST Diagnostic attributes

LU & LMPYear

Time

Regen cap

/Function

Bioregion: Mulga Lands

Reference state: Extent of pre-clearing Regional Ecosystem (RE) 6.3.13Atriplex spp., Sclerolaena spp., species of Asteraceae and/or short grasses open-herbland on alluvial plains

Source: Daniel Ferguson, Queensland Herbarium

Need to assess which of the 10 key criteria are affected and by how much i.e. Condition

Soil

Vegetation

Regenerative capacity/ function

Vegetation structure & Species composition

1. Soil hydrological status2. Soil physical status3. Soil chemical status4. Soil biological status5. Fire regime6. Reproductive potential7. Overstorey structure8. Understorey structure9. Overstorey composition10. Understorey composition

NSW, SB Bioregion, Cumberland SF, Transect 2 (ex-comp 3a, 7a, 7b, 7c)Function – Regenerative capacity

Criteria #1 Criteria #2

Criteria #3 Criteria #4

Disturbance regime

NSW, SB Bioregion, Cumberland SF, Transect 2 (ex-comp 3a, 7a, 7b, 7c)Function – Regenerative capacity

Criteria #5 Criteria #6

NSW, SB Bioregion, Cumberland SF, ex-comp 3a, 7a, 7b, 7c Vegetation structure

Indicators:#13: Height#14: Foliage cover#15: Age structure

Indicators:#16: Height#17: Foliage cover#18: Age structure

Criteria #7

Criteria #8

NSW, SB Bioregion, Cumberland SF, Transect 2 (ex-comp 3a, 7a, 7b, 7c)Species composition

Criteria #9

Criteria #10

Conclusions

• Vegetation types are kept in various extents and condition states depending on social and economic ideals, values, goals and drivers

• Conversions to non-vegetated, non-native and highly modified native commenced at European settlement; the reference state

• Conventional mapping and monitoring of vegetation type, extent and condition using remote sensing is only started around 70 years ago

• Transformations are changes in condition and extent relative to a reference state: function, structure & composition

• Net gains in condition and extent(spatially and temporally) can be accounted for as changes in function, structure and composition

• To achieve long term lasting changes in extent and condition we must engage land managers using language of public and private benefits

• Scenarios that aim to transform extent and condition must be informed locally by evidence of previous land management practices

Thank you

Supplementary Information

Dynamics

Rainfall is assumed the main driver of natural system dynamicsIt is a key dataset used in developing chronologies of effects of land management on vegetation condition:• Period 1900 – current1

• Average seasonal rainfall (summer, autumn, …) is highly correlated to LMP2 and their effects on function, structure and composition

• Rainfall anomaly is calculated above and below the mean• Two year running trend line is fitted to give insights into El Niño and La

Niña events3

1. Bureau of Meteorology: modelled monthly rainfall 5km resolution national dataset 2. LMP – Land management practices3. El Niño events are associated with prolonged periods of below average rainfall and at times, devastating droughts. A rapid onset of a La Niña event, following a severe El Niño event, have been associated with major soil erosion events and major cycles of regeneration and germination

Differentiating natural disturbance events and land management practices

Photos by Garry Dowling and Richard Thackway

2006 20132009

Low intensity grazing - cell grazing sheep

Severe dust storm Low intensity grazing - cell grazing sheep

Reference state: Pre-clearing Regional ecosystem 6.3.13 Atriplex spp., Sclerolaena spp., species of Asteraceae and/or short grasses open-herbland on alluvial plains

Illustrates a baseline but not the Reference state

Photo: Melinda Laidlaw

High intensity cattle grazing -Continuous or set stocking

Source: https://publications.qld.gov.au/storage/f/2014-09-18T23%3A49%3A36.560Z/re-seq-landzones.pdf

A Framework for Program Evaluation

Source: http://sphweb.bumc.bu.edu/otlt/mph-modules/ProgramEvaluation/ProgramEvaluation2.html

Need continuous social learning linked to adaptive management

Yapp, Walker and Thackway (2010)

VAST 1 Residual/unmodified*

VAST II1 Transformed

* Reference state

Multiple benefits (ecosystem services) and condition states