• Completed project

Tipping points in ecosystem structure, function and services

We investigated how marine ecosystems respond to change, and identified tipping points, risks and ways of managing them.

Project Leader Duration Budget
Simon Thrush (University of Auckland) April 2016 – June 2019 $3,470,000

Overview

We investigated the effects of multiple stressors and cumulative impacts on marine ecosystems. Stressors can be caused by unexpected events (such as earthquakes) or impacts of human activities (such as increased sediment, nutrients or contaminants in the water), or climate change. These stressors can lead to ‘tipping points’ when rapid transformations occur, and an ecosystem loses its capacity to cope with change. Tipping points often involve the loss of valuable marine resources, or ecosystem services.

This was the first nationwide assessment of how estuaries and harbours in Aotearoa New Zealand respond to change. Our results show that as coastal waters become more turbid and nutrient levels increase biodiversity and ecosystem function decline. Rocky shores and kelp forests are also affected, with elevated turbidity decreasing the ability of these systems to respond to change and recover from disturbance. 

Coastal and marine ecosystems deliver multiple benefits and services, so it is important to deal with the cumulative impacts of stressors and develop management strategies to reduce their impact. Our research suggests there is a growing need to apply an ecosystem-based management framework to manage risk and sustain New Zealand’s coastal ecosystems. This is even more important given the ongoing impacts of climate change.

Location

This is a national project.