Final report

Project objectives

In May 2000, Environment Waikato announced their intention to introduce a variation to the Waikato Regional Plan aimed at protecting the water quality of Lake Taupo. Research and monitoring indicated that increasing nitrogen (N) losses from pastoral and urban land to the lake were one component of water quality that was being adversely affected by human activity. Trends in land use apparent then indicated that there was a clear risk of further increases in N loss to the lake as farmers continued to increase production, forest owners investigated conversion of forests to pasture and sub-division for residential purposes continued without reticulated sewerage.

In response to the agreed need for new farm management options, AgResearch worked with farmers to establish the objectives of a local research project. Resulting from this work, Puketapu Group was funded by the Ministry of Agriculture and Forestry Sustainable Farming Fund (SFF) to carry out project SFF 02/110 ‘New profitable land management options for Lake Taupo Catchment’.

The current project (SFF Project 05/114) has been run by DairyNZ (formerly Dexcel Ltd) and funded by SFF, Environment Waikato and Meat and Wool NZ. The project aimed to complete the experiments and extend the results of SFF 02/110 with the aim of building the capability of farmers and rural professionals to deal with the new reality of pastoral farming in the Lake Taupo catchment.

Approach

Experimental work on field trials commenced in the original project was completed in 2006 and has been summarized in a report available on the MAF SFF website (www.maf.govt.nz/sff/about-projects/search/02-110/02-110-final-report.pdf).

A workshop was held for rural professionals in Taupo on 17 September 2007. This was widely advertised through NZIPIM, DairyNZ and Environment Waikato rural professional contact lists. Eighteen rural professionals representing farm consultants, resource management consultants, accountants, Environment Waikato and the fertilizer industry attended. Presentations from Duncan Smeaton (AgResearch), Jan Hania (Environment Waikato) and Bruce Thorrold covered background to the Lake Taupo variation, how the variation was going to be implemented, results from the experimental and modeling work done as part of the project and other results from linked work such as the Ravensdown studies on ecoN use conducted at Waihora.

Small group meetings were held with farmers in December 2007. Letters were sent to all farmers in the Lake Taupo catchment, with an invitation to meet with project leaders either as individuals or groups to discuss the project and their own farm situation (Appendix 4). Personalised invitations were sent to the funding partner Incorporations. Ten separate meetings were held with people representing an estimated 20% of the land holdings in the catchment. The owners represented a range of farm sizes from smaller private farms through to large Incorporations.

What were the main findings from this project?

Results from the experiments conducted in the first stage of this project clearly demonstrated several key points:

Role of grazing animals in driving N leaching.
The importance of winter grazing as a source of N leached.
The potential of well managed feed export systems based on perennial grasses to have very low levels of N leaching.
The potential for higher input feed export systems, especially with cultivation and large N fertiliser inputs to have high N leaching.

The experiments did not produce a simple solution for farmers. However they were valuable in providing local data to assist in interpreting and supporting the conclusions drawn from experiments elsewhere.

The modelling studies carried out to test economics of different management options illustrated that there are a range of options that farmers can use to manage N. The economics of these options depend on factors such as pasture growth responses to DCDs, relative process of beef and lamb and the long-term economics and cash flow of forestry. However, despite the initial promise of options such as DCDs, these studies have revealed no simple solution that delivers step-change N leaching and economic benefits.

Workshops and farmer meetings indicated a wide range of readiness among farmers and rural professionals to respond to the new realities of farming in the Lake Taupo catchment.
What difference has this project made?

The project has had several benefits:

Engaged farmers in the science that underpins the whole EW variation, and has provided local data against which to test the results from other studies.
Lifted capability in N management - many farmers are now quite well-informed on the dynamics of N cycling.
Enable farmers to contribute their ideas to the research community - this has led to on-going involvement with further research work.
For most farmers in the catchment it has laid the groundwork for understanding the linked economic-N management goals they will face in future.
Identified the need for on-going one-to-one interaction to overcome the social issues involved in making such a large shift in land use policy.

Outputs from the project

Full project report

www.maf.govt.nz/sff/about-projects/search/02-110/02-110-final-report.pdf

Publications

Nitrate leaching and productivity of some farming options in the Lake Taupo catchment. K. Betteridge, C J Hoogendoorn, B S Thorrold, D A Costall, S F Ledgard Proceedings of the New Zealand Grasslands Accociation Conference 69:123-129
http://www.grassland.org.nz/publications.php?proceeding=82