Planning CertaintyA challenge for Investment

April 2014

Tom Chesson – CEO Australian national Irrigators Council

Murray Smith – Principal Engineer, Agriculture and Regional Water (GHD)

Planning certainty

• Similarities and differences between New Zealand and Australia

• Irrigation Corporations• Water security – balance between water for

consumptive use and the environment• Vegetation management• Nutrient management (emerging focus in AUS)

Land Use changes• Australia’s geological history and climatic condition (low rainfall

and high evaporation) has created a unique very flat continent accumulated with enormous amounts of salts in the soil – saline lakes/streams is a natural part of the Australian landscape and native vegetation has adapted to these conditions.

• Salinity - 2.5 M ha (potential to increase to 12 M ha); Acidity – 90 M ha (Williams, J & Saunders, D 2003, CSIRO)

• Land use change to agricultural land after European settlement has resulted in clearing of native vegetation and changes in landscape hydrology.

• Increase the need for water supply and fertilizer input to support increased pasture and crop production.

• The system has now become vulnerable to leakage of sediments, nutrients and water beyond root zone.

Nutrient Loss Risk factors

• Nutrient loss from farms can be costly and has potential to cause degradation of waterways, groundwater and add to greenhouse gases.

• The major nutrients that cause environmental pollution are:

• Nitrogen• Phosphorus

Farm Nutrient Loss Index To assess the risk of nitrogen and phosphorus loss for the Australian grazing industries

• Industry standard to guide farm advisors on identifying risky nutrient practices.

• Four nutrient loss pathways

Farm Nutrient Loss Index• Key factors of FNLI that cause nutrient loss are:

1. source of nutrients2. factors of nutrient transport

• “where there is a source of nutrient, there is a potential source for nutrient movement off-farm”

Best Management Practices for Nitrogen Application

General guidelines for N management

– Reduced stocking rates and stocking intensity to minimise N losses from urinary deposition.

– Only apply N when pasture is actively growing and can utilise the N.

– Avoid applying N fertiliser near streams/riparian zones and over drainage lines in a paddock.

– Light N application is the best practice - 50 to 60 kg N/ha in any single application, 21 to 28 days apart.

Nitrate leaching and denitrification

– Avoid the following practices:• Over application – Nitrate leaching• High rates of N on waterlogged

soils – Denitrification• Application to soil at high

temperature - Volatalisation – Free draining soils - avoid

application before heavy rainfall and for at least 2 to 5 days after heavy rains.

– Avoid pugging by heavy stocking intensity during high rainfall periods, as this will result in either increased drainage or surface run-off loss of N.

Reef Rescue Water Quality R&D Program: Overview of research projects

• Grazing industry– Improving grazing management practices to enhance ground cover and

reduce sediment loads– Runoff Nitrogen generation rates from pasture legumes – an

enhancement to reef catchment modelling• Sugarcane Industry

– Evaluating and improving A Class practices to control ‐ nutrient losses from sugarcane

– Advanced drip and optimised furrow irrigation to minimise sediment, nutrient and pesticide losses to the environment through deep drainage and runoff from sugarcane and banana industries

• Horticulture Industry– Minimising off farm movement of nitrogen ‐ in the north Queensland

banana industry• Dairy Industry

– Validating the cost/benefits of improved fertiliser practices and quantifying nutrient loads and pathways from irrigated dairy pastures