Monday, 10 February 2020

What's good for the goose is good for the gander


It’s the question on the tip of every dairy farmer’s tongue: How can we reduce our greenhouse gas footprint?

The good news is there are already some options at farmers’ disposal that’ve been scientifically proven to work. According to experts in the field, what many farmers don’t know is that the tools are already being used extensively to improve water quality.

The exciting thing about this co-benefit of reducing emissions and improving water quality using the same tools is that they’re already widely used and really practical.

Farm Systems and Environment Science Impact Leader Dr Robyn Dynes says scientific evidence supports a correlation between lowering nitrate leaching and a reduction of farm methane and nitrous oxide levels.

There are exceptions to the rule, but scientists are now confident of what they’ve long suspected; that running a farming operation with lower nitrate leaching results in the ‘co-benefit’ of lowering your greenhouse gas footprint. It’s only now, after several years of data gathering and research, much of it now published in science journals, that the evidence is demonstrable.

Dr Dynes says: “Balancing your environmental footprint is good farming practice and the vast majority of farmers get that. “The exciting thing about this co-benefit of reducing emissions and improving water quality using the same tools is that they’re already widely used and really practical. It’s things like reducing the application of nitrogen fertilisers, managing supplementary feed supplies and homegrown feed sources, and then adjusting the stocking rate to lower feed supply, they all reduce your emissions.”

Other options include keeping your highest breeding-worth cows. Better genetics was always going to be part of farming cleaner and greener. But scientists are now also confident that reducing stocking numbers should not automatically decrease production levels. The key, Dr Dynes says, is maintaining and managing your pasture quality and quantity levels right through spring and early summer, and that when you find yourself in a feed deficit, you maintain the appetite drivers of your cows. 

“That extra attention to detail pays off. It’s a balancing act, as it is every year. The crucial period is that calving-to-balance- date phase, balance date being when feed grown exceeds demand from cows. There is a myriad of variables, including monitoring when soil temperatures are high enough for nitrogen application. But with the right advice, farmers should be able to pull the right levers and lower their emissions.” 

There are, as with any business, risks. Investing in a feed pad can improve water quality, but can in some instances lead to an increase in emissions. This is known as pollution swapping. To negate this risk, farmers need to make sure their effluent disposal strategies are sound.

“We have data now that’s proving farms are still able to maintain production. We simply need to keep optimising feed per hectare to farm within water quality and greenhouse gas emissions limits,” Dr Dynes says.

Existing climate tools

  • Better genetics eg keep higher breeding-worth stock.
  • Maintain and manage pasture quality and levels.
  • Reduce nitrogen fertiliser application.
  • Manage supplementary feed supplies & homegrown
    feed supplies.
  • Adjust stocking rate to lower feed supply.