Changes in Water Resources Systems: Methodologies to Maintain Water Security and Ensure Integrated Management (Proceedings of

Changes in Water Resources Systems: Methodologies to Maintain Water Security and Ensure Integrated Management (Proceedings of Symposium HS3006 at IUGG2007, Perugia, July 2007). IAHS Publ. 315, 2007,35-40

The Service Provision Index (SPI): linking environmental flows, ecosystem services and economic value

LOUISE KORSGAARD^1,2,3, tORKIL JØNCH-CLAUSEN¹, dAN ROSBJERG² & jESPER SØLVER SCHOU³

1 DHI Water & Environment, Agern Allé 5, DK-2750 Hørsholm, Denmark

louisekorsgaard@hotmail.com

2 Institute of Environment and Resources, Technical University of Denmark, Bygningstorvet, Building 115, DK-2800 Kongens Lyngby, Denmark

3 National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde, Denmark

Abstract Environmental flow is the water needed for the proper functioning of ecosystems. Ecosystems, in turn, provide a wide range of valuable services. Providing for environmental flow is not exclusively a matter of sustaining ecosystems, but also a matter of supporting humankind and livelihoods. None of the existing environmental flow assessment methods explicitly link environmental flow to ecosystem services. Consequently, such methods cannot readily deliver inputs to economic valuation studies. Furthermore, existing holistic environmental flow assessment methods are very resource demanding (time, money, data). This is a real constraint to undertaking environmental flows assessments, in particular in developing countries. This paper attempts to bridge the current gap between biophysical scientists, socio-economic scientists and decision-makers in Integrated Water Resources Management (IWRM) by presenting and encouraging the use of a Service Provision Index (SPI). It is a pragmatic, operational and flexible approach that is easy to use while maintaining a holistic and comprehensive assessment of environmental flows.

Key words decision support systems (DSS); environmental flows; economic valuation; ecosystem services; Integrated Water Resources Management (IWRM); multi-disciplinary approach; Service Provision Index (SPI)