Protecting Water Quality & Biodiversity

The project provided:

  • A comprehensive literature review that has highlighted some very important areas for new work and for some key extension messages to be developed from existing data.
  • Identified farmer groups according to “type” and this will guide our future efforts in engaging the farming community in that we can target these groups specifically.
  • A review of existing biological models that might fit the identified need that is to provide a model that will correlate the impact on farm production of planting trees in a variety of landscapes and environmental systems.
  • The research found that whilst no single model exists there are some models being used in Australia and New Zealand that could be used to provide some of the answers we seek and that the potential is there for some work to be undertaken to modify the closest matches to our requirements to meet our requirements
  • Identified the future work necessary to provide a framework for increasing biodiversity levels on dairy farms in SW Victoria for whatever reason.

The project highlighted some strongly held beliefs in relation to the best way to engage farmers and it also identified some major differences of opinion within and between agencies on not only the importance of biodiversity within a farming systems context but also some fundamental problems associated with clearly articulating exactly what it is that each agency (on behalf of the community) means by biodiversity and what indeed (if any exist) are the targets for the replenishment of this resource in our region.

To further complicate this issue there is major misalignment between the industry and the agencies on the issue of biodiversity what it means, who requires what of whom and who is being seen as responsible for the problem (if indeed there is a problem – a fact that many of the farmers surveyed would contest).

Protecting Water Quality & Biodiversity


Sustainable Systems of Dairy Production - PR Bird

A review of water quality, biodiversity, soil salinity/acidity, farm forestry, shade/shelter and productivity issues, and the likely impact on these of revegetation of dairy farms


1. Sustainable systems of dairy production

Dairy farming in the 3 major dairy regions in Victoria is currently based on year-round pasture grazing, with some fodder and grain crops, a relatively low-cost system of production. Irrigation is used in the northern region of Victoria over the summer months to sustain production from pastures. Peak production occurs in October/Nov and a trough in May-June-July. There is an increasing trend towards more intensive production systems, with more grain being fed and more fertiliser being applied (AD 2000). While feedlot-based systems are presently uncommon, there are at least 2 now established in the SW region that have cow numbers around 1200-1400. The numbers of dairy farms has been slowly declining over the past 30 years while total production has been increasing, as a result of greater production per cow and greater numbers of cows (AD 2000). Of the milk produced, 92% goes into products such as butter, cheese and powders, while 8% is processed for sale in liquid form. Over 60% of the manufactured products are exported and almost 50% of the milk.

Sustainable systems of dairy production


2. Biodiversity

Revegetation projects should aim for multiple benefits, including biodiversity benefits. Land development for agriculture has resulted in severe losses in species and ecological communities (NRE 1997c) and a critical task now is to halt and redress those losses. This action might also have a positive impact on sustainable grazing systems.



3. Water quality in streams & ground

Nutrient enrichment of surface waters contributes to the increasing incidence of cyanobacteria blooms and other less noxious blooms of algal species in SE Australia, and reduces the oxygen-carrying capacity of the water, so that in-stream biota are also diminished in numbers and species (EPA 1995)

Water quality in streams & ground


4. Soil salinity & acidity

It is estimated that nearly 2 million ha (10% of the agricultural land) in WA is currently affected by salinity and, on current trends, 6 million will ha will become unfit for agriculture over the next 50-100 years (Margules Pöyry 1998). The Murray-Darling Basin (MDB) area is also expected to lose 6 million ha in that time. Even if effective programs are put in place to counter soil salinisation, another 2 million ha will become unfit for agriculture in WA (and probably a similar amount in the MDB) in those 50-100 years (CRC Dryland Salinity Business Plan 2000). Other environmental impacts of salinity include loss of biodiversity and effects on physical infrastructure (roads, buildings, bridges, pipes, sports fields). Whilst much of these lands have an annual rainfall less than 500 mm, there is a substantial percentage in the 500-700 mm category; the area that is relevant to the present WestVic Dairy report. There are few salinity problems in areas having >800 mm of rainfall per annum.

Soil salinity & acidity


5. Shelter effects on productivity, health & welfare of livestock

A brief summary is presented below of general shelter effects that might result from trees placed in the landscape for benefits of shelter, biodiversity and recharge control.

Shelter effects on productivity, health & welfare of livestock


6. Farm forestry/agroforestry

While the focus of this review is on farm forestry applications in the dairy regions, it is important to first briefly review farm forestry in a broader context, so that all possibilities are explored. The main farm forestry options available are summarised below, followed by a discussion on factors that determine the choice of option. This section concludes with an exposition of the 'dehesa' system of land management – this system can be regarded as a wide-spaced woodlot option for the production of timber or horticultural produce.

Farm forestry/agroforestry


View the full document Sustainable Systems of Dairy Production