Supported by:

CSIRO Sustainable Ecosystems grazing land research
by Dr Andrew Ash and Dr Kenneth Hodgkinson, CSIRO Sustainable Ecosystems

Background

Rangelands are environments where natural ecological processes continue to shape vegetation, wildlife and landforms and where economic utilization is based primarily on natural capital. Typically these are areas where rainfall is too low or the land too steep for growing dry land crops. Cattle or sheep grazing is the most common land use but mining companies, Aboriginal communities, tourist businesses, nature conservation agencies and the military also use the land.

About 80 per cent of Australia is rangeland and comprises woodlands, shrublands and grasslands. Rangelands are grazed by domestic animals and kangaroos, goats and pest animals. Much of the vegetation is natural. Agricultural grasslands on the other hand are created by cultivation, exotic plants, fertiliser and water. Although natural, rangelands have problems of soil erosion, loss of palatable perennial grasses and invasion by exotic woody weeds.

There is 70 CSIRO staff researching semi-arid and arid rangelands. They aim to solve problems of poor land management and poverty in rural and regional areas. Research is developing better management and monitoring for grazing lands with the aim of improving profitability and maintaining landscape function for wildlife and animal production.

Research

1. Grazing management

   This research aims to understand how grazing strategies affect vegetation, soils, production and economics. Research outputs are management guidelines for balancing production and nature conservation. A systems approach links biophysical processes to economics at the enterprise scale.

   Examples of recently completed projects include:

   ECOGRAZE – This eight year project in north-east Queensland developed guidelines for maintaining land in good condition and to encourage restoration of land degraded by overgrazing. The guidelines have been widely adopted across northern Australia and incorporated into grazing land management education packages for farmers and university students.

   NIRS – Near Infra-Red Spectroscopy has been developed to diagnose the diet quality of free ranging cattle. The research was developed in partnership with industry. The NIRS technology is currently being commercialised.

   Current grazing management projects include:

   Enhancing landscape productivity and profitability by maximising retention of water, sediments and nutrient in grazing lands
   Sediments and nutrients from grazing lands affect the health of streams, estuaries and the Great Barrier Reef. Retention of sediments and nutrients on grazing lands not only benefits water quality but also improves pasture and animal productivity. This project aims to develop landscape management options and monitoring procedures to better manage sediments and nutrients on grazing lands and to improve profitability of grazing enterprises.

   Assessing economic/environmental trade-offs
   This project is developing methods to assess the impacts of different management technologies on the production and profitability of rangelands and the potential impacts on land, water and other natural capital.

   Grazing intensification
   In the more extensive areas of northern Australia, means of intensifying animal production by better fencing and water infrastructures and more even utilisation of grassland is being researched. The research is finding out how intensification affects animal performance, grazing distribution, grassland composition and soils.

2. Landscape monitoring

   Landscape Function Analysis has been developed in southern woodlands and is now being adapted for northern rangelands grazed by cattle. The ground based method uses simple measurements of landscape function and soil surface. This method was developed in sheep grazed rangelands but has been found useful for assessing mine site rehabilitation, conservation of faunal habitat and military damage. A manual on CD with hyperlinked images is available and provides rapid data reduction. The procedure has been widely adopted in assessment of Australia’s rangelands. This ground-based method is limited by small scales. Scaling-up for rangeland assessment at property and regional levels requires remote sensing. Currently remotely sensed landscape 'leakiness' indices are being developed.

3. Climate impacts

   Rainfall in Australia's rangelands is generally low and highly variable. Droughts and floods are a natural part of this cycle. Large temporal variability in grass production poses significant challenges to pastoral managers because it is difficult to balance animal numbers with grass supply. Seasonal climate forecasts provide pastoralists with early warning so they can avoid the crippling economic and ecological effects of droughts. Current SOI-based forecasts do not provide sufficient lead time or predictability for pastoralists.

   The climate variability research is bringing different disciplines together including ocean physics, atmospheric science, pasture ecology, and resource economics to develop better and more relevant seasonal climate forecasts. This is achieved through a project titled 'Oceans to Farms'. The Oceans to Farms work demonstrated that the ocean has longer term 'memory' that can be used to predict plant growing season length, rather than rainfall, and that these forecasts can be delivered at critical times for management decisions on stocking for the next year i.e. in June/July. The research showed that by varying animal numbers in response to the forecast that profitability could be improved by 15-20 per cent without negatively affecting key resource indicators like soil erosion or frequency of perennial grasses.

4. Improving adoption of natural resource management practices

   Many grazing management problems do not require more technical understanding and the major constraints to improvement in management outcomes are adoption and the need to take a more systems based approach to management practices. In an effort to improve the uptake of research results the program is investing more effort into socio-economic research. This involves developing new participatory action research approaches to increase uptake of research. Another area of research is to better understand how social networks operate in pastoral systems.