Capacity, pressure, demand, and flow: A conceptual framework for analyzing ecosystem service provision and delivery

• Published in: Ecological complexity 2013-09, Vol.15, p.114-121
• Main Authors: Villamagna, Amy M., Angermeier, Paul L., Bennett, Elena M.
• Format: Article
• Language: English
• Subjects: decision making; Ecological pressure; Ecosystem services; ecosystems; Inventory and assessment; natural resource management; new methods; Regulating services; scientists; Service capacity; Service demand; Service flow; society; terminology
• ISSN: 1476-945X
• DOI: 10.1016/j.ecocom.2013.07.004

•Capacity, demand, pressure, and flow are important components of ecosystem service delivery.•The interpretation of these components varies among service types (e.g. provisioning versus regulating).•Differences among service types warrant different measurement methods.•Ecosystem service provision is sustainable when flow does not increase pressure or degrade capacity.•Regulating service flow is the ecological work done to mitigate pressure. Ecosystem services provide an instinctive way to understand the trade-offs associated with natural resource management. However, despite their apparent usefulness, several hurdles have prevented ecosystem services from becoming deeply embedded in environmental decision-making. Ecosystem service studies vary widely in focal services, geographic extent, and in methods for defining and measuring services. Dissent among scientists on basic terminology and approaches to evaluating ecosystem services create difficulties for those trying to incorporate ecosystem services into decision-making. To facilitate clearer comparison among recent studies, we provide a synthesis of common terminology and explain a rationale and framework for distinguishing among the components of ecosystem service delivery, including: an ecosystem's capacity to produce services; ecological pressures that interfere with an ecosystem's ability to provide the service; societal demand for the service; and flow of the service to people. We discuss how interpretation and measurement of these four components can differ among provisioning, regulating, and cultural services. Our flexible framework treats service capacity, ecological pressure, demand, and flow as separate but interactive entities to improve our ability to evaluate the sustainability of service provision and to help guide management decisions. We consider ecosystem service provision to be sustainable when demand is met without decreasing capacity for future provision of that service or causing undesirable declines in other services. When ecosystem service demand exceeds ecosystem capacity to provide services, society can choose to enhance natural capacity, decrease demand and/or ecological pressure, or invest in a technological substitute. Because regulating services are frequently overlooked in environmental assessments, we provide a more detailed examination of regulating services and propose a novel method for quantifying the flow of regulating services based on estimates of ecological work. We