Jane Chrystal

Doctor of Philosophy
Study Completed: 2017
College of Sciences


Thesis Title
Dairy wintering systems in Southern New Zealand - Quantification and modelling of nutrient transfers and losses from contrasting wintering systems

Read article at Massey Research Online: MRO icon

In the southern South Island of New Zealand, the losses of nitrogen to water from dairy cow wintering systems is an issue of concern. Traditional grazed forage crop systems are challenging in terms of potential harmful impacts on stock, soil and water. Alternative housed systems are potentially relatively costly and there are challenges associated with the management of effluent in cool wet climates. Mrs Chrystal characterised existing systems according to a knowledge framework that she created to outline the key components, and interactions, of the systems. This framework identified a lack of systems currently available that utilised the low-cost brassica crop but incorporated some form of off-paddock system. She developed a novel low-cost wintering system that filled this gap. Measured and modelled data showed a reduction in nitrogen losses to water from the new system compared to crop wintering, to levels that were similar to losses from a barn system.

Professor Michael Hedley
Dr Ross Monaghan
Professor David Horne