Vegetable Research & Innovation

The MPI SFF root zone reality project (401484) and the HortNZ northern fluxmeters project (HortNZ RI 1009) – summary of year 1 and year 2 activity

In July 2014 two projects were commissioned to establish a network of passive-wick tension fluxmeters in commercial cropping farms in Canterbury, Manawatu, Hawke’s Bay and Matamata/Pukekohe. The fluxmeter network is being used to measure nutrient concentrations of nitrogen (N) and phosphorus (P) in drainage water under good management practices.
This report summarises activity for the period between fluxmeter installation (August 2014 to May 2015) and 30 October 2016.
The experimental design across the network includes four monitor regions, three sites per region and 12 fluxmeters per site. The fluxmeters were installed to collect drainage at a depth of 1 m, selected to represent a depth below which nutrient uptake across most crop species is likely to be minimal. Sites provide a range of cropping systems, soil types, climatic conditions and management practices relevant to each region.
A range of soil, plant and leachate measurements are being collected from the sites on an ongoing basis and key results are summarised below. Respective soil fertility ranges considered as ‘low’, ‘moderate’ or ‘high’ are listed as follows: for mineral N, 0–50, 50–150 and > 150 kg N/ha, for anaerobically mineralisable nitrogen (AMN), 0–100, 100–200 and > 200 kg N/ha and for Olsen P, 0–20, 20–50 and > 50 mg P/L.