All in South Australia

Changing patterns of salt distribution in irrigated soils

mgabelle — Mon, 29 Mar 2010 23:47:47 +0000

The compilation of a clearer picture of the changing patterns of salt distribution in irrigated soil by Flinders University of SA student Megan Sebben under the supervision of the head of the South Australian Research and Development Institute’s Water Resources and Irrigated Crops Unit, Jim Cox.

IDs and People

Program:

National Program for Sustainable Irrigation

Research Type:

PhD Student

Host Organisation:

National Program for Sustainable Irrigation

Researchers:

Megan Sebben

Subjects

Subjects:

Water (General)

Irrigation

Keywords:

salt

irrigated soils

Current Activities

Status:

Active

Location

State & NRM Region:

South Australia

Boneseed Rust: A highly promising candidate for biological control

Mon, 18 Aug 2008 01:28:35 +0000

IDs and People

Program:

Defeating the Weed Menace R&D Program

Program Theme:

Identifying biocontrol agents for priority weed species

Research Type:

Research Project

Legacy (KMS) Project ID:

CEN24

Host Organisation:

CSIRO Entomology

Researchers:

Dr Louise Morin

Subjects

Subjects:

Data and Information

Weeds

Keywords:

Weeds

weed

biocontrol

boneseed rust

Project Information

Summary:

This project investigated the use of Endophyllum osteospermi (a systemic rust fungus) in the biological control of boneseed (Chrysanthemoides monilifera ssp. monilifera). This systemic South African rust fungus has been found to reduce growth and the reproduction of plants by causing extensive deformation of infected branches (witches’ broom).

Boneseed is a Weed of National Significance, which occurs mainly in Victoria, South Australia and Tasmania.

Outcomes:

This project has generated new approaches to the establishment and detection of boneseed rust that will play important roles in future development of biological control agents for boneseed. Through the adaptive approach to the research and appropriate applications to AQIS, the Principal investigator has also achieved innovative new approaches to tge use of traditional 3-tiered host specifity esting for biocontrol agents. Each of these new aspects of knowledge may have applications beyond the specific case under study - rust fungus control of boneseed.

Current Activities

Status:

Complete

Background

Project Background:

This project is building on research conducted in South Africa in the mid-1990s.

Aims:

This project aims to complete the host-specificity testing phase of the boneseed rust to provide the necessary data to finalise the risk assessment for this rust and build a strong case to support its release in Australia. This will be achieved by:

Carrying out inoculations of the six non-target plant species on which penetration occurred in initial host-specificity tests, and microscopically examining samples taken 4 weeks after inoculation to determine if the rust has successfully colonised plant tissue. (Modified objective proposed to L&W Australia in March 2007 and accepted on 7 June 2007)
Preparing and submitting an application to release the rust to the regulatory authorities.
Developing a molecular-based tool to enable detection of the rust in symptomless plants after release since it can takes up to 2-3 years for visible disease symptoms to develop.
Negotiating with AQIS to determine an acceptable approach to release the rust from the quarantine facility.

Location

State & NRM Region:

South Australia

Victoria

Tasmania

Long term sustainability of precision irrigation

Mon, 16 Jun 2008 22:46:58 +0000

There is now strong evidence of serious soil structural decline under precision irrigation, but practical tools to identify the conditions for this degradation are not yet available. We will identify a range of paired (precision-irrigated / non-irrigated) texture-contrast soils in vineyards across the Barossa Valley and assess the impact of this irrigation on soil properties important for root growth and water uptake.

IDs and People

Program:

National Program for Sustainable Irrigation

Research Type:

Research Project

Legacy (KMS) Project ID:

UAD25

Host Organisation:

University of Adelaide

Researchers:

Dr Robert Murray

Subjects

Subjects:

Salinity

Soils

Water (General)

Irrigation

Keywords:

soil types

Precision Irrigation

Soil Degradation

Project Information

Outcomes:

Initial work in the project has been at 18 sites within 8 vineyards. Water quality is generally good; only 4 of these sites have been irrigated with moderately saline water (EC >2dS/m). Infiltration rates were generally poor. Two thirds of the sites were below 2 mm/hour and more than one quarter were less than 0.4 mm/hr. The rates midway between, and directly under drippers were similar in 60% of cases. Otherwise they were much larger midway between the drippers.

Penetration resistance measured in the laboratory at field capacity (–10 kPa) was generally high with an average value of 1.1 MPa. At the 4 salt-affected sites, penetration resistance was 26% greater between drippers. At the other 14 sites, penetration resistance was 29% greater under drippers. Field penetration resistance 24-48 hours after irrigation was assessed at 35 points in 2 vineyards. In Vineyard 1, only 7% of measurements were below 1 MPa while 38% were above 2 MPa. In Vineyard 2, 80% of measurements were above 2 MPa and 40% were above 4 MPa. Air-filled porosity at field capacity (–10 kPa) was also poor. Two thirds of the samples studied were below 5% and almost all were below 10%. Air-filled porosity was generally greater (by about 50%) midway between drippers.

Current Activities

Status:

Active

Current Activities:

With the wide adoption of drip irrigation to conserve water it’s important that we get it right. Research preceding this project suggested that the concentration of water that occurs immediately beneath drippers may cause serious subsoil structural decline.

The project embarked on a close comparison of subsoil structure under, and far away from drippers at vineyards in the but this work revealed no dramatic differences. However, as application rates in the Barossa Valley are usually less than 1 ML/ha, we have recently gathered similar data in and around Mildura and propose to do the same near Griffith shortly; at both locations water quality is good and application rates are much higher (5-10 ML/ha). The work in the Barossa Valley did however disclose universally poor subsoil structure in the 10 vineyards examined. In practically all cases drainage was poor, aeration was very poor, and mechanical resistance to root growth was high. Such adverse subsoil conditions point to a pressing need for improved preparation for permanent plantings and ongoing management of subsoil structure.

The alternative will be shallow-rooted plants dependent on frequent irrigation for survival; this is not consistent with the current need to maximize water use efficiency. We are in the process of confirming this hostility to root growth via root length density measurements on intact soil cores taken from the same locations. We are also pursuing study sites where more “heroic” and careful soil preparation has preceded planting.

Background

Project Background:

Precision irrigation, particularly drip irrigation, is used extensively in Australian vineyards to conserve water but there are soil related issues that may influence its long-term sustainability. Although real application rates (ML/ha) may be relatively low, the concentrated nature of precision irrigation causes subsoil beneath emitters to be wet for extended periods. When seen in relation to local rainfall, these artificial increases in the concentration of water have the potential to degrade soil structure. The quality of irrigation water is a further issue.

Decreasing availability of water for irrigation inevitably leads to compromises in water quality. Irrigation with saline water increases soil sodicity which can cause serious soil structural decline. This project aims to assess the extent of these problems in the Barossa Valley, to establish the roles of soil type and irrigation water in causing them, to quantify the vulnerability of soils to them and to develop and test management strategies to minimize and reverse them.

Aims:

To establish the roles of soil type, irrigation water quality, amount of applied precision irrigation and methods of application of precision irrigation (e.g. pulse versus continuous) in soil degradation.
To quantify the vulnerability of soils, in combination with various water qualities, to degradation under precision irrigation using a ‘hazard rating’.
To develop and test management strategies to minimize and reverse soil degradation under precision irrigation.
To prepare, with LWA editorial and publishing support, a grower-friendly guideline on best management practices for the industries using precision irrigation to reduce irrigation induced soil structure decline, and identification of any trade-offs between best management practices for soil structure, nutrients, pesticides and root zone salinity.
To provide technical support to a separate project team charged with interpreting the projects findings for other climatic zones and commodities.
To communicate new findings and additional outcomes to policy makers (SA, Vic, NSW, MDBC, NWC).

Location

State & NRM Region:

South Australia

Locations:

Barossa Valley

Improved Seasonal Forecasts for Wool Producers in Australia’s Pastoral Zone

Mon, 08 Oct 2007 06:34:58 +0000

IDs and People

Program:

Land, Water and Wool

Program Theme:

Climate Variability

Research Type:

Demonstration Project

Research Scale:

State

Legacy (KMS) Project ID:

QNR30

Subjects

Subjects:

Climate (General)

Livestock (Sheep)

Livestock (Pastoral)

Landscape Management

Keywords:

Woolgrowers

Land Management

Stocking Rate

Climate Variability

Pastures

Seasonal Forecasting

Project Information

Summary:

Much of Australia’s rangelands are characterised by extreme climate variability which represents a major challenge for woolgrowers. In order to maintain or increase productivity while minimising negative environmental impacts on the land, producers need access to reliable seasonal climate forecast (SCF) information at critical times for key management decisions.

Current Activities

Status:

Pending

Background

Aims:

The objective of Improved Seasonal Forecasts for Wool Producers in Australia’s Pastoral Zone was to support and provide tools for the regional Managing Climate Variability Sup-program projects. It aimed to make SCF products more relevant to producers and their advisors through pasture growth simulation and prediction using Aussie GRASS, a national spatial pasture growth program.

Location

State & NRM Region:

New South Wales

Queensland

South Australia

Western Australia

Victoria

Geographic Zone:

Broadacre: Wheat-Sheep

Broadacre: Pastoral

Optimising wool production and profitability in the Mid-North riparian areas

superuser — Mon, 08 Oct 2007 04:23:50 +0000

This project measured the effectiveness of alternative stock management and other rehabilitation methods that aim to improve pasture and wool quality from riparian areas. It quantified as far as possible the costs and benefits of these methods, and provided practical guidance to woolgrowers on how to implement them to improve both production and environmental management.

IDs and People

Program:

Land, Water and Wool

Program Theme:

Rivers and Water Quality

Research Type:

Research Project

Research Scale:

Region

Subjects

Subjects:

Conservation

Landscape Management

Salinity

Livestock (Sheep)

Rivers and Wetlands

Keywords:

Woolgrowers

Land Management

Riparian

Environmental Management

Native Vegetation

Sustainable Grazing

Pastures

Increase production

Project Information

Summary:

Current Activities

Status:

Complete

Background

Project Background:

Rivers and their adjacent riparian areas in much of the Mid-North of South Australia were once prime grazing country, typified by native grasslands and fresh water. These areas are now showing increasing signs of stress and degradation, including rising river salinity and reduced pasture productivity.

Aims:

The aim of this project was to assist wool producers in the Mid-North region of SA to determine the most cost-effective way to manage riparian frontages, optimising profit and production, while also improving the condition of pastures and native vegetation, channel banks and the creek environment.

Location

State & NRM Region:

South Australia

Geographic Zone:

Broadacre: Wheat-Sheep