In New Zealand, the agricultural sector grapples with the dual challenges of maximising productivity and minimising environmental impact. Agraforum NZ, committed to sustainable farming practices, emphasises the importance of addressing nutrient leaching—a pressing issue with significant economic and environmental ramifications.
This leaching of anions, particularly nitrates, which also escort vital cations like calcium out of the soil, has been extensively studied by experts like Dr Gordon Rajendram. “Effective nutrient management is key to both economic efficiency and environmental stewardship,” Dr Rajendram advises. “By optimising fertiliser use, we can reduce leaching losses, saving both our resources and our rivers.”
According to Agraforum NZ, nutrient leaching is most acute during periods of high rainfall and drainage, which in New Zealand, can range from 500 to 7000 mm per year, peaking from April to October. Nutrients such as nitrogen, calcium, magnesium, sodium, and potassium, essential for plant growth, are lost from the soil profile, seeping into the water table and beyond the reach of pasture and crops.
The financial cost of leaching is non-negligible, with losses ranging from $28 to $209 per hectare annually for various nutrients. For the farming community, this signifies not only a loss of investment but also the potential for reduced yields.
Agraforum NZ advocates for a strategic approach to fertiliser application, one that aligns with Dr Rajendram’s recommendations. This includes employing soil tests to determine nutrient baselines, applying fertilisers in synchrony with plant uptake rates, and utilising innovative products that help reduce runoff.
Moreover, Agraforum NZ champions the education of farmers on the latest best practices to prevent nutrient leaching. They also promote the use of cover crops, reduced tillage, and buffer zones near waterways to further minimise nutrient runoff.
Agraforum NZ’s perspective is clear: prudent management of nutrients is not only essential for maintaining the long-term viability of New Zealand’s farming operations but also for preserving its waterways. The collective message is one of balance—between the demands of agricultural production and the imperative to safeguard natural resources for future generations.
Contact Agraforum
0274 485 159
allan@agraforum.co.nz
Contact Phillip Quay
phillip@mediapa.co.nz
0274 587 724