The Service Provision Index(SPI) : Linking Environmental flows, Ecosystem Services and Economic Value

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-economicscientists and decision-makers in Integrated Water Resources Management (IWRM) by presenting and encouraging theuse of Service Provision Index (SPI). It is apragmatic, operational and flexible approach that is easy to use while maintaining a holistic and comprehensive assessment of environmental flows.