Taking a look at aquatic life below ground

A seminal review has just been completed on ecosystems within true groundwater (the phreatic or permanently saturated zone), mostly within alluvial aquifers, which are the largest and most widespread aquifers across New Zealand.

The review, commissioned by Horizons Regional Council on behalf of all regional councils, and funded by an MBIE Envirolink advice grant, draws on published or otherwise publicly accessible literature to assess what is currently known about groundwater ecosystems in New Zealand to inform future freshwater policy development and groundwater management. Up until recently, water management in New Zealand has focused primarily on managing groundwater as a physical resource and protecting groundwater-dependent ecosystems on the land surface (e.g., wetlands).

Phreatoicus typicus, a 20 mm long isopod from Canterbury’s groundwater. [Photo: Nelson Boustead]

Our review describes aquatic life within aquifers, outlines the ecosystem services and values supported by groundwater ecosystems, and discusses the key factors that affect and threaten groundwater ecosystems.

Māori values, beliefs and practices associated with groundwater are outlined, along with the current legislative context for groundwater management, and priority research needed to better understand and manage groundwater ecosystems.

Recommendations include a national survey of groundwater ecosystem state and function (including hydrological and water chemistry attributes), development of standard sampling methods and indicators for measuring and reporting on groundwater ecosystem health, and identification of toxicity thresholds of key groundwater taxa or communities for contaminants such as nitrate. 

Further information

Horizons report - Groundwater ecosystems: functions, values, impacts and management. [PDF]  

Contact

Regional Manager - Wellington
Research subject: Ecosystems