Catchments

Four small catchments of the Taita Experimental Basin are being studied. The soils, geology, meteorological and hydrological characteristics and vegetation are well documented. The flux of reactive phosphorus through the system is examined in detail. Reactive phospherous run-off from a grassed catchment was about twice as much as from forested catchments.

The legume gorse (Ulex europaeus) is one of the most widespread nitrogen (N) fixing species and is also one of the most invasive weeds of New Zealand. Despite its widespread occurrence, little research has been undertaken on N cycling in gorse ecosystems. This lack of knowledge is important since gorse covers up to 900 000 ha in New Zealand and there is a potential for a large environmental impact from the cycling of large amounts of N fixed by gorse entering waterways and water bodies.