Ecosystem Services and Productive Base for the Basin Plan

"May 2010".

Project Number: Part 1 - Implementing a systems approach to support adaptive management of river and wetland health in the MDB; Part 2 - Review of Interventions and Development of habitat Preference Curves for biota at Murray Icon Sites; Part 3 - Natural versus Artificial watering of floodplains and wetlands - M/BUS/248.

MDFRC item.

1 of 4 reports associated with project see (Clarification of Definitions in the Water Act 2007), (Feasibility Assessment of Ecological Outcomes (indicators) proposed for the Basin Plan Monitoring and Evaluation Program) and (‘Natural’ versus ‘Artificial’ watering of floodplains and wetlands).

The MDFRC, together with Professor Lin Crase and Drs Rhonda Butcher and Pierre Horwitz, have consulted to produce this review of ecosystem services and the productive base. Special attention has been paid to the wider meaning of these terms and their likely impact on the formulation of the Basin Plan. The Murray-Darling Basin Authority (MDBA) is preparing the Basin Plan, a strategic plan aimed at delivering integrated and sustainable management of water resources within the Murray-Darling Basin (MDB). This is a complex task involving planning on a very large scale, rarely tackled elsewhere (MDBA 2009a). The plan will provide a fundamental framework for future water planning arrangements and will be based on the best available scientific, social, cultural and economic knowledge, evidence and analysis. The Water Act 2007 (the Act) requires that the MDBA establish Sustainable Diversion Limits (SDLs) that reflect an Environmentally Sustainable Level of Take (ESLT). The ESLT for a water resource is the level at which water can be taken from that water resource which if exceeded, would compromise: key environmental assets (KEA) of the water resource or key ecosystem functions (KEF) of the water resource or the productive base of the water resource or key environmental outcomes (KEO) for the water resource. According to the Act, environmental assets include: water-dependent ecosystems ecosystem services sites with ecological significance. This report is used to test the relationship and consistencies between the current MDBA ESLT approach (based on KEA and KEF) and the delivery of ecosystem services and the productive base. More specifically, we test the hypothesis that an ESLT that does not compromise: key ecosystem functions key water dependent ecosystems key sites with ecological significance. will not compromise: ecosystem services or the productive base. In order to objectively assess these propositions for the purposes of this report we consider ecosystem services separately to the other KEA, notwithstanding that the Act defines the former as a subset of the latter. 4 Key Findings Ecosystem services are the benefits that humans obtain from ecosystems. They can be divided into provisioning, regulating, supporting and cultural services. They are influenced by ecosystem conditions and ecosystem processes. This broadly aligns with the notions of KEA and KEF respectively, as presently interpreted by the MDBA. Tracing the relationship between the value of ecosystem services and ecosystem performance is no simple task. The notion of the productive base is not widely employed or well-supported by the literature1. Taken broadly it equates to ensuring that provisioning, regulating, supporting and cultural services are also supported. There would appear to be little to be gained by endeavouring to separately distinguish threats to ecosystem services from threats to the productive base and they should be treated synonymously. Thus if not compromising KEA and KEF results in the delivery of ecosystem services there are grounds for arguing that the productive base will also avoid compromise under these conditions. It has been possible to formulate an ecosystem services classification for the Basin Plan. The proposed classification makes use of the existing work in the field. There is insufficient scope to test all elements of this approach although it is possible to make some defensible qualitative judgements about the ecosystem services pertinent to the plan. The classification appears in Table A.