Managing pasture surpluses or deficits in spring is the key to maintaining quality and persistence going into summer, says Ravensdown agronomist Tim Russell.
Instead of looking at each farm’s impact and mitigations, integrated catchment management is a holistic way to view farming’s impact on local waterways, the company says.
Water will be tested by Ravensdown’s laboratory and environmental consultants will use nutrient loss-minimising tools.
“Farmers and other local community members are saying ‘the quality of our particular waterway is not good enough and we’re not going to wait for someone else to come in and improve it,’ ” said Ravensdown’s business manager environmental, Mark Fitzpatrick.
Mitigating nutrient impacts one stream or one farm at a time can be more costly and less effective, he says.
“Water quality is often an accumulation of consequences affected by the choices of a variety of community members. Communities are motivated to look at catchment impacts, and our new service will provide the means for taking a bigger-picture approach and help promote good farming practice.”
Ravensdown’s environmental consultants will combine information from laboratories with farm- and catchment-scale modelling.
“This can then inform decisionmaking onfarm, resulting in catchment-wide environmental impact reduction,” Fitzpatrick says.
Consultants will use the agricultural version of the LUCI (land utilisation capability indicator) modelling tool jointly devised by Victoria University and Ravensdown. LUCI enables a trained consultant to show farmers the location of potential ‘hot spots’ at risk of phosphate losses. The computer model indicates the scale of possible mitigations so helps improve decisionmaking and nutrient management.
The model’s complex algorithms incorporate slope, water movement, groundwater, soil map data, climate, land class and data from the Overseer nutrient management tool.
“LUCI can provide insights at a farm, catchment and even national level. It is this new software that enables our consultants to look at a range of factors at a catchment level,” Fitzpatrick says.
LUCI is a hydrological and spatially explicit model developed at Victoria University of Wellington by associate professor Bethanna Jackson.
It is the world’s only model able to accurately and efficiently model nutrients from farm through to catchment at a nationwide scale.
The Ravensdown Environmental team will apply LUCI-AG, a bespoke agricultural version of this model alongside Overseer to better inform nutrient budgets.
They will be better able to identify and estimate nitrogen and phosphorus loss from critical source areas (CSAs) and provide mitigation options.