FARMING WITHOUT HARMING in an OLD, FLAT, SALTY LANDSCAPE

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FARMING WITHOUT HARMING in an OLD, FLAT, SALTY
LANDSCAPE

• John Williams
• CSIRO Land and Water

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FARMING WITHOUT HARMING

• With Landcare and public funding we have begun
• to repair the damage,
• to stabilize the situation,
• heal the wounds,
• treat the symptoms.
• Landcare must now move to focus on treating the
  cause of the degradation. That will not be so
  easy.

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FARMING WITHOUT HARMING

• Can we do it in an old,dry,flat salty continent?

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So Whats the problem?
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Oz is a dry, flat, salty landmass

• Australias geological history makes us quite
  different to most other parts of the world.
• Our continent is a very old, flat, stable
  landmass that has eroded through time,
  accumulating sediments and salts.

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Oz is a dry, flat, salty landmass

• Much of the salts are carried from the oceans in
  rain, deposited, trapped and accumulate in the
  soils, regolith, lakes and groundwater, and have
  done so over millenia.
• These accumulated salts were blown and
  redistributed across the landscape during the
  extremely dry periods of geological time.

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ThereforeThe arteries and veins of the
Australian landscape are not in good shapethey
need special care!
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Native Vegetation evolved to balance salt and
water

• Trees, woody shrubs and perennial grasses
  comprised much of Australias native vegetation
• The perennial vegetation, deep roots takes full
  advantage of any available water, thus minimizing
  the amount of water that leaks past the root zone
  to groundwater.

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irrigation
interception
transpiration
evaporation
run off
drainage
Courtesy of Val Snow
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Replacing native vegetation set water,nutrient
and salt moving

• Australian rural production systems were built on
  annual crops and pastures replaced the deep
  rooted trees and shrubs under which the landscape
  evolved. This radically changed the nature and
  seasonal patterns in the hydrological and
  nutrient cycles.
• The consequence is that current farming systems
  leak water and nutrients beyond the root-zone.

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The Australian irony

• whilst our Agricultural productivity is
  constrained by lack of water and nutrients
• fundamental cause of much of our land
  degradation is an excess of water and loss of
  nutrients at key periods of the year.

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OZ AGRO-ECOSYSTEMS ARE IN TROUBLE

• We Are Wasting What We Need
• We Are Damaging the Landscape in the Process !!
• Salinity/erosion
• Acidification
• Habitat loss
• Water Quality

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EFFECTIVENESS OF CURRENT FARMING SYSTEMS TO
CONTROL DRYLAND SALINITY

• Long term leakage rates are
• usually 2 to 10 times greater than that which
  occurred in the native ecosystems.
• strongly dependent on amount and distribution of
  rainfall and soil properties.
• Halved with deep rooted perennials
• Yet still twice or three times that of the native
  vegetation.

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Mean annual drainage - Vertosol
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LEAKAGE INTO LANDSCAPE FROM BENEATH AGRICUTURE
15 to 150 mm/yr
DRAINAGE FROM LANDSCAPE
WATERTABLE
0.5 to 5 mm/yr
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OZ AGRO-ECOSYSTEMS ARE IN TROUBLE

• Differences between the Australian landscape and
  that in most other parts of the world mean that
  agricultural systems that are sustainable
  elsewhere do not necessarily transfer to our
  unique conditions.

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Damage to Environmental Assets

• soil nutrient depletion
• soil acidification
• soil structural decline
• soil biological decline
• dryland and irrigation salinization
• wind and water erosion
• contamination with residues of agricultural
  chemicals

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Damage to Environmental Assets

• loss of habitat and biodiversity
• river processes and environmental flows
• nutrient, salts and pollutants to wetlands,
  rivers and water bodies
• contamination of groundwater with nutrients, salt
  and pollutants
• riparian, remnant vegetation damage and rural
  tree decline
• decline in native pastures and environmental
  value of rangelands

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IMPACTS OF SALINITY

• Saline Rivers
• drinking, irrigation
• Loss of Habitat
• wetlands, riparian
• Damage to Infrastructure
• roads, buildings
• Loss of Productive Land

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OK so whats the way forward for us in
Queensland Landcare?
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Salinity Hazard Risk

• Salinity Hazard Exists when
• Salt present in
• soil,
• regolith,
• groundwater
• There is an increase in deep drainage beneath
  root zone that exceeds discharge capacity of
  landscape

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Prevention of salinity is a far better investment
than any attempt at control or management.

• Once you can see salinity symptoms it is usually
  too late.
• Develop knowledge and capability to assess
  salinity hazard and risk.
• Retain and re-establish native vegetation in
  recharge areas of landscape with a salinity
  hazard.
• Salinity impacts and biodiversity impacts of
  Vegetation management go together.

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Salinity Risk and catchment response

•  Develop a means to recognise how catchments
  function with respect to salinity risk.
• Develop the means to link salt, stores, loads
  and concentrations to groundwater dynamics and
  changes to land management practice.
•  Develop a catchment-scale equilibrium theory to
  understand the long-term trends and decide which
  areas are irretrievably lost to salinisation, and
  which are most amenable to recovery or treatment.

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G-factor
Mean discharge capacity
G
Total recharge of catchment
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Why emphasis on groundwater systems?
recharge
We can manage these
groundwater response
salinity damage
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Wanilla, Eyre Peninsula, SA - impact on salinity
after 20 years
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Solutions?

• Treatment of cause
•          Recharge control to reduce (a) the rate
  of rise of groundwater, (b) the area of land
  affected by salinity, (c) the delivery of salt
  to water resources
•          Interception of fresh water to reduce
  the rate of rise of groundwater and delivery of
  salt to land and water resources

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REVOLUTION IN LAND USE

• Our Landscapes require a mosaic of
• Commercial Land Uses that are Ecologically
  Sustainable
• Land uses that provides a suite of Ecosystem
  Services which are valued and paid for by
  stakeholders and beneficiaries

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REVOLUTION IN LAND USE

• Earn more of our living from goods and services
  derived from deep rooted, perennial trees and
  shrubs.

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REVOLUTION IN LAND USE

• Commercially driven tree production systems
  and/or new tree species, to be developed for
  large areas of the current crop and pasture zones
  of the Basin.
• These would include trees to produce fruits,
  nuts, oils, pharmaceuticals, foods from native
  plants, and forestry products such as specialty
  timbers, charcoal, and biomass energy.

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REVOLUTION IN LAND USE

• New farming systems made up of novel mixes of all
  the best current annual and perennial plants, the
  best agronomy, companion plantings, rotations and
  combinations.
• New forms of cereals, pulses, oilseeds and
  forages selected or bred for characteristics that
  substantially reduce deep drainage and nitrogen
  leakage.

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REVOLUTION IN LAND USE

• Refined land assessment tools that
• best locate trees, other perennial plants,
  high-value annuals, and native species to meet
  water quantity and quality targets, and
  biodiversity goals
• facilitate re-assignment of land so that on some
  parts we double productivity and other parts are
  removed from production to yield ecosystem
  services

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Profit - drainage matrix .
Courtesy Brian Keating CSIRO Sustainable
Ecosystems
100
u
90
Profitable, but leaky systems
No-win
Exploit
80
70
Annual cropping
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Drainage (mm/year)
50
Improved agronomy
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Ecosystems Services
Opportunity cropping
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Novel mixtures of annalsand perennials
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Native vegetation
0
Win-win
Tradeoff
0
50
100
150
200
Profit (/ha)
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To realise this vision

• We will need to pioneer the development of a new
  landscape, a mosaic of
• tree crops driven by large-scale industrial
  markets such as biomass fuels
• high-value annual crops
• mixed perennial-annual cropping system
• Significant areas devoted to maintaining those
  elements of native biota dependent on native
  vegetation.

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Take Home Messages

• By building new farming systems and new
  industries derived from tree and shrubs that
  capture all the water, nutrients and carbon
• we treat the environmental damage at its cause
  and
• turn the leaked material into food and fibre and
  ultimately wealth

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Take Home Messages

• a real win-win situation.
• Lets go for it.

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REVOLUTION IN LAND USE

• Requires a mosaic of
• Commercial Land Uses that are Ecologically
  Sustainable
• Land uses that provides a suite of Ecosystem
  Services which are valued and paid for by
  stakeholders and beneficiaries

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Now What aboutLand uses that provide a suite of
Ecosystem Services which are valued and paid for
by stakeholders and beneficiaries
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Ecosystem services

• the conditions and processes through which
  natural ecosystems, and the species that make
  them up, sustain and fulfill human life
• Daily (1997)

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Ecosystem services

• Production of goods
• e.g. food, pharmaceuticals, genetic resources
• Regeneration services
• e.g., maintenance of soil fertility, purification
  of water and air, dispersal of seeds and spores
• Stabilisation services
• e.g., control of pests and diseases, mitigation
  of floods, maintenance of ecosystem resilience,
  detoxification
• Life-fulfilling services
• e.g., provision of aesthetic and cultural values,
  spiritual inspiration
• Provision of options for the future

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Why ecosystem services?

• A powerful communication tool
• simplifies natures complexity
• focuses on benefits and beneficiaries
• provides a framework for sustainability
• Facilitates dialogue key natural resource
  management issues
• options, trade-offs, markets, externalities
• An integrating concept

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What is important in valuing ecosystem services?

• What people will give up to keep them
• What people will pay to use them
• How much they affect property values
• What it might cost to replace them
• Availability of technological substitutes
• BUT, MANY services are beyond value and not all
  decisions should be made on the basis of economic
  costbenefit

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New commodities and markets
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Farming without Harming

• Can we do it?

• YES

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WHAT CAN WE DO?

• PLAN
• RESEARCH
• IMPLEMENT
• MONITOR
• EVALUATE