Finding proactive ways to reduce nutrient loss has been the driver behind the Aparima Community Environment (ACE) 'Future Farming' scenario modelling.
ACE is made up of six Aparima catchment groups (Lower Aparima, Mid Aparima, Upper Aparima, Waimatuku, Pourakino and Orepuki - six of the 35 catchment groups supported by Thriving Southland) which are all focussed on working together to protect their environment and their rural communities.
Environment Southland is currently developing its Regional Plan to give effect to the National Policy Statement for Freshwater 2020 and Te Mana o te Wai, which will bring with it the requirement for reductions in nutrient loss across the region. Rather than wait for the plan to be fully developed, ACE member and Fonterra supplier and shareholder Jolene Germann says the group wanted to get a head-start in this space by investigating different actions that could be taken to help minimise the loss of nutrients through farming practices.
"We wanted to do something that was quite forward thinking. We know at some stage there are new limits and regulations coming that is going to mean we'll have to change the way we are farming but we don't know yet what those limits are - but that doesn't mean we have to wait for the regulation to come before we can start thinking about how we should be farming in the future," she says.
ACE enlisted Chris Beatson from consultancy partner Agri Magic to carry out the 'Future Farming' scenario modelling, which saw desk top studies carried out on five case study farms - three Fonterra dairy farms and two sheep and beef farms. These farms range in location, topography and climatic variations to represent farms across the Aparima Catchment, meaning most farmers will be able to identify a case study farm they can relate to.
All five farms had their baseline data collected for the 2016-17 season, which was chosen as the base year to represent the last completed season prior to the Southland Water and Land Plan being released. This baseline data provided a detailed picture of the farms' environmental footprints during this period.
Individual workshops were then carried out where trusted advisors for each farm, such as neighbours, consultants and catchment group members, helped develop a suite of possible mitigations for each farm. Agri Magic then modelled these mitigations in OverseerFM to record changes in nitrogen and phosphorus losses and Farmax to quantify changes in earnings before interest and tax (EBIT) to determine what reductions in environmental footprints could be achieved, and the impact on the financial sustainability of the farms.
The mitigations modelled across the five farms ranged from small scale changes such as meeting current legislative requirements, implementing good management practices, retiring less productive areas and reducing stocking rates, through to complete farm system changes such as investment in off-paddock structures, wetlands, organic dairy farming and forestry.
Key findings from the study included:
Across the five case study farms, modelled reductions in nitrogen loss of 4-31% could be achieved through small changes to the farm system, when compared to the base systems. These changes had minimal modelled impact on farm profitability.
Any farm system changes which focus on reducing winter feed areas, reducing autumn and winter stocking rates on pasture or including wetlands and other setbacks on farm were found to be likely to reduce nutrient losses. The level of investment required for these mitigations differed and had variable impacts on EBIT.
Alternative farm systems such as an organic dairy farm or sheep milking led to reductions in modelled nutrient losses. There was limited financial data on these farm systems therefore further work would be required to ascertain the full financial implications of these scenarios.
Although there were common nutrient loss drivers across all farms, each farm was different in the magnitude of change which could be achieved for the scenarios modelled. This indicates mitigation options should be investigated and quantified for each property prior to changes being made.
Jolene says what she found most surprising from the results was the reductions that could be made simply through small changes to farm systems.
"Sometimes we get bogged down with the full scope of the reductions and think that it is too hard to achieve. While some of the reductions that have been talked about through the modelling are massive and will have an impact on the farm, that doesn't mean we shouldn't do anything at all," she says.
"The magnitude of some of the easy wins were quite surprising. Some of the nitrogen reductions could be made just by optimising the farm systems - they were quite significant without requiring many changes to your farm and they had no effect or even a positive impact on EBIT. Things like better effluent management, better nitrogen management and using plantain... they are pretty achievable to do and they did make a difference."
Jolene urges other farmers to view the full results from the scenario modelling and see what can be applied on their own farms.
"We'd encourage you to look at implementing some of the changes that were modelled - many were successful at reducing the nutrient footprint without impacting on farm profit, so they really are a no-brainer," she says.
For more information on ACE's scenario modelling including individual reports for each of the farms involved visit thrivingsouthland.co.nz/ace.