Hurunui river catchment nitrate nitrogen dynamics examined using continuous concentration monitoring

Abstract

The middle reaches of the Hurunui River passes through the Culverden tectonic basin before cutting through another basement rock gorge on its way to the Pacific Ocean. The Culverden basin contains flat and rolling land for irrigated pasture and pine plantations. Current proposals for former forestry land would increase the irrigation extent, grazing intensity and conversion of plantation forestry to grazing agriculture. Ngāi Tahu Property Limited is a Māori incorporation owning the Balmoral Forest and interests in expansion of grazed agriculture. Te Rūnanga o Ngāi Tahu is the iwi authority representing the rūnanga and hapū covering the Hurunui River and Culverden basin, as well as owning Ngāi Tahu Property Limited. The authors have been working alongside both organisations to characterize the water quality trends and nutrient volumes moving through the Hurunui River system.