RECENT maps from the Waikato Regional Council show nitrogen trends and where they are increasing. Trends shows highest concentrations occurring in the northern areas (Pukekohe, Pukekawa and Waiuku), the southern Hauraki Plains and Hamilton Basin. The concentrations in these relatively intensively used areas contrast with low nitrate-N concentrations in less developed Coromandel and Taupō sub-regions. PHOTO WRC.
A NEW research partnership between the Crown and Ravensdown is hoped to fend off a nitrogen pollution crisis that saw Dutch farmers take to the highways in massive protests in July. Dutch farmers objected to their Government’s proposals for tackling nitrogen emissions that included a radical cut in livestock with an estimated 11,200 farms forced to close and another 17,600 farmers required to significantly reduce their livestock. Other proposals included a reduction in intensive farming and the conversion to sustainable “green farms”.
DUTCH SYSTEM BROKEN Head of food and agriculture at World Wildlife Fund Netherlands Natasja Oerlemans said the Dutch agricultural system was broken, and warned the Netherlands was facing a painful period of uncertainly and unrest. The Government failed to act on scientific data for years, meaning drastic measures were now needed to tackle the issue, she said. While the industry’s focus on increasing livestock productivity had a detrimental impact on the ecosystem. In the Waikato, increasing nitrogen pollution of groundwater is also being driven by intensive farming, dairy and market gardening. A report to the Waikato Regional council Environmental Performance Committee on August 11 stated nitrate in regional groundwater commonly exceeded the drinking water guideline, with medians being over the maximum acceptable value at 11% of the State of the Environment monitoring network sites. The highest concentrations were associated with market gardening and dairy farming activities. The highest concentrations occur in the northern areas (Pukekohe, Pukekawa and Waiuku), the southern Hauraki Plains and Hamilton Basin. The concentrations in these relatively intensively used areas contrast with low nitrate-N concentrations in less developed Coromandel and Taupō sub-regions. DATA COLLECTION Data was collected from a regional network of 110 state of environment (SOE) wells and a network of 80 ‘Community’ or rural school water supply wells. Data from the Community supply network indicates that nitrate-N trends at these wells are predominantly increasing. Coinciding with the Dutch protests, Agriculture Minister Damien O’Connor announced on July 28 the Government is co-investing in a $22 million programme aimed at significantly reducing agricultural greenhouse gases and nitrate leaching. The Government committed $7.3 million across seven years to the N-Vision NZ programme through the Ministry for Primary Industries’ Sustainable Food and Fibre Futures (SFF Futures) fund. Ravensdown is leading the programme, and will contribute $11 million, with Lincoln University and Plant & Food Research providing research expertise. Ravensdown and Lincoln University will contribute in-kind funding to the value of $3.8 million. “The programme focuses on three technology streams,” Damien said. “N-Retain is a new nitrification inhibitor technology that will look at new ways to block the biological processes in the soil that lead to nitrous oxide emissions and nitrate leaching. “N-Test is a new soil test to inform nitrogen fertiliser decisions on pastoral farms, that will help capitalise on the nitrogen already in soil organic matter. This could mean less nitrogen fertiliser needs to be applied. “The third product, N-Bio Boost, is a fungal bio-inoculant to increase nitrogen use efficiency, which will examine how naturally occurring fungi boost the nitrogen efficiency of plants as another way to future-proof productivity.” The projects in the $22 million seven-year initiative, are led by Lincoln University researchers Dr Hossein Alizadeh, Professor John Hampton and Dr Wadia Kandula, and are intended to harness the power of natural strains of soil fungi to increase efficiency of nitrogen use by plants. NATURAL STRAINS OF FUNGI “The Lincoln University researchers have discovered natural strains of fungi that reduce the activity of specific microbes, which are involved with nitrogen cycling and losses,” Ravensdown general manager of innovation and strategy Mike Manning said. “These nitrogen losses can occur as nitrate leaching through the soil which has potential detrimental effect on waterways, and as nitrous oxide, a potent greenhouse gas emission. “Although it occurs naturally in pastoral soils at a relatively low level, the fungi can be applied to soil as either a prill or seed coating. Doing so increases the level of the fungi and therefore alters the nitrogen cycle to reduce nitrogen losses. “Research to date indicates this has a strong potential to mitigate both greenhouse gas emissions and reduce nitrogen loss to waterways,” he said. “What we can say is that it offers a lot of promise. We have got more work to make sure it performs as well in the field as it does in the laboratory. “How good is it in the paddock? We don’t know yet. Does it save nitrogen leaching by 10, 20, 30%? We would like to think it would be closer to 20-30% than five or 10% but we don’t know until we do the paddock work. “If it saves nitrogen that’s otherwise leached, then that improves the receiving water aquifers, surface water and other things so, the goal is to save nitrogen from being leached and save it from being released as nitrous oxide – and if you do that then there is less going into the environment.” The field work was going to take years. “I don’t think you could do it in one year and one season because as you know you can have a wet season or a dry season. You have probably got to do it over a couple years and a couple of seasons to make sure it performs as well in the dry as it does in the wet, and we haven’t done that so it would be a couple of years at least I would say before you get that level of confidence.” STOCK REDUCTION He understood why the Dutch farmers were going to be required to reduce stock. Without technology like the researchers were investigating, stock reduction was the next option, which was unpalatable from a farmer’s point of view, he said. “And that is the choice. You either invest in technology – some of them will work and some of them probably won’t – but you invest in technologies to reduce your losses,” Mike said. “If you were not to do that the next quickest way is to reduce numbers of animals and that comes at a cost to the farmer and to the country both. So that’s not a particularly smart way to do it. I think you are better to try and work with technology to get there.” The field trials were underway with some of them taking place in the Waikato region. “There’s no guarantee we need to try. It looks promising, fingers crossed it will eventuate to the level that we expect. They [farmers] just want to know that something is going on, that somebody is doing something, and that’s the important thing. “They will be comforted that they won’t end up like the Dutch farmers did.”
