Traditionally, the impact of human activity on an ecosystem has lacked context when planning restorative ecosystem mitigation and management strategies. Multiple human activities over time and space, the resilience of a particular ecosystem, and the stress caused by many individual or related, overlapping activities that generate cumulative effects may affect the overall "ecosystem response footprint," or ability of an ecosystem to adapt and change to human activity.
A team of marine scientists reviewed the most recent perspectives on ecological footprints to rigorously define the term "ecosystem response footprint" as the ecosystems response or ability to adapt to change over space and time caused by external factors, rather than simply the summation of effects due to external factors in a particular area. The group additionally outlines how organizations can shift from stressor-limiting approaches to holistic ecosystem based management approaches which focuses on building ecosystem resilience and recovery.
The team published their review on 15 August 2023 in the journal of Ecosystem Health and Sustainability.
"Our conceptual footprint framework seeks to provide a perspective to manager and scientist on understanding ecosystem response to cumulative stressors and effects through understanding ecosystem dynamics," said Jasmine M.L. Low, co-lead author of the review paper and doctoral candidate in Marine Science at the University of Auckland in Auckland, New Zealand.
The team argues that the footprints of human activity and stressors in marine and coastal ecosystems differ from the ecosystem response footprints due to four primary factors:
1) The presence of multiple stressors can affect the relationship between stressors and the response of the ecosystem,
2) Temporal mismatches in ecosystem responses are present because of lags in recovery generated by legacy and carry over effects even once the stressors have stopped,
3) Local place and time context dependent characteristics can change how an ecosystem responds to a specific stressor and
4) Stressors can cause indirect effects on ecosystems that are connected.
The authors emphasize that defining ecosystem response footprints in holistic terms and a dynamic environment is challenging but necessary to ensure the long-term health and resilience of an ecosystem.
"Our goal with this review was to move past the current stalemate in ecosystem-based management and limit-setting approaches. We need to use current ecological information to put the ecosystem front and center of environmental management to help boost and progress action in management decisions," said Rebecca V. Gladstone-Gallagher, co-lead author of the review paper and lecturer in Marine Science at the University of Auckland.
"We call for a refocusing on ecosystems in place and time and a nuanced view of how they respond to change. We believe that alongside managing stressors, we need to manage ecosystems for resilience and recovery, and actions should be focused on assessing what can be done upstream or in surrounding areas to improve… resilience, safeguarding against future degradation," Gladstone-Gallagher said.
Integrating both space and time into the relationship between stressors and an ecosystem can help organizations assess how long a particular response will last and whether or not an ecosystem will recover after mitigation or management efforts. Beyond the spatial area of the cumulative ecosystem response footprint, the authors argue that the "depth" of the response between stressors and the ecosystem accounts for the magnitude or timing of the interaction between the ecosystem and a stressor.
The team looks forward to the implementation of their guidelines to improve the management of ecosystems, both marine and otherwise, worldwide. "The next steps are to integrate these ecosystem response footprint concepts into marine spatial planning, policy frameworks, resource consent, assessments of cumulative effects and risk assessment frameworks," Low said.
Other contributors include Judi E. Hewitt and Simon F. Thrush from the University of Auckland in Auckland, New Zealand and Joanne I. Ellis from the University of Waikato in Hamilton, New Zealand.
This work was supported by the New Zealand National Science Challenge Sustainable Seas Project 1.1 (Ecological responses to cumulative effects) established by the Ministry of Business, Innovation, and Enterprise, New Zealand (C01X1901).
