PhD and postdoctoral research programmes conducted at the NZ–China Water Research Centre

Currently there are a number PhD and postdoctoral research programmes underway at the centre.

• Ammonia oxidisers in New Zealand soils and their role in nitrate leaching and nitrous oxide emissions.

The aim is to study ammonia oxidiser communities in New Zealand soils and their relationships to nitrate leaching and nitrous oxide emissions.

• Reducing nitrate leaching by regulating drainage with tillage-centred agricultural management practices.

The aims of this study are to: 1) Identify how and under which conditions nitrate leaching can be reduced via regulating drainage using tillage-centred management practices, 2) quantify the amount of N leaching reduction that can be attributed to reduced N concentration and drainage, respectively.

• Dinitrogen(N2) and Nitrous oxide (N2O) fluxes from grazed pasture soil after animal excreta deposition.

Direct N2 measurement method will be used to explore how the ratio of nitrate to carbon, and varied soil properties, affect N2O production and consumption processes under field conditions.

• Reducing phosphate losses into water by treating farm dairy effluent before application to land

The objective of this project is to determine phosphate leaching losses to artificial drains from treated farm dairy effluent compared with those from untreated FDE applied to land. The research hypothesis is: ‘that land application of treated farm dairy effluent has a lower phosphate leaching loss than untreated farm dairy effluent’.