Looking back over ten years of collecting data from pasture-based dairy farmers, it is encouraging to see that there has been progress made with regards to improved sustainability. Two of the main goals of Trace & Save is to support farmers to farm in a more sustainable manner and to create evidence of progress where it is being made.
The reductions in emissions on the 20 pasture-based dairy farms over the past five years are an encouragement to any farm that would like to reduce their environmental impact. The most significant improvements have come from increased feed conversion efficiency, a higher proportion of pasture in the diet, and lower N fertiliser application rates.
Manure is both a waste product with the potential to pollute, and a potential fertiliser. One challenge in dairy production is managing manure in a way that is advantageous for agricultural production, while minimising the potential negative impact on the environment and public health.
Soils containing excessive concentrations of sodium and magnesium can have detrimental effects on plant growth and productivity. These minerals can accumulate in the soil to high levels due to various factors, including irrigation with water containing high salt content, excessive application of fertilizers rich in these minerals, and the deposition of animal excreta from grazing animals, which contain significant amounts of sodium and magnesium.
The value of regenerative farming is the desire of farmers to reduce their environmental impact and align their practices with the services that are inherently part of all ecosystems. But this is not a new concept at all.
The case study was aimed at finding opportunities for pasture-based farmers to use water more efficiently by the installation of water meters on centre pivots, which accurately measured how much was water is used for irrigation.
Taking advantage, or greater advantage, of biological nitrogen fixation, seems like a logical option for a chemical nitrogen substitute. Adding legumes to your cropping system, and managing them well, has great potential to add significant amounts of nitrogen to your system, in a more sustainable way than chemical fertilisers.
Every farmer should assess their system and see where they still have opportunities to improve. This will probably show them whether their stocking rate is too low, too high, or just right. The data in this case study would suggest that very few farms are in the just right category.
We did not need this research to give us confidence in the principles we advocate for in terms of nitrogen fertiliser management on dairy pastures. But it is encouraging to see other research which confirms what we have been observing.
We have a huge database of soil results from many pasture-based dairy farms throughout the coastal region of South Africa. I thought it might be interesting to have a look at some of the trends that can be seen from this database.