The Conservation of Freshwater Ecosystem Values (CFEV) (pronounced "see-fev") program is an initiative of the Department of Natural Resources and Environment Tasmania (NRE Tas). Its aim is to ensure that priority freshwater values are appropriately considered in the development, management and conservation of the state's water resources.
The program has undertaken an assessment of the conservation management priorities (CMP) of all freshwater ecosystems throughout the state. Through its comprehensive audit of the state's freshwater ecosystems, the CFEV program offers the first Comprehensive, Adequate and Representative (CAR) assessment of freshwater ecosystems conducted in Australia. This gives users the rare luxury of being able to manage all freshwater ecosystems with comparable conservation management information, rather than having access to only limited data on a range of flagship ecosystems.
The CFEV program completed a statewide audit and conservation evaluation of Tasmania's freshwater-dependent ecosystems, which used existing environmental data to identify where aquatic values exist and their overall priority for conservation management. These two exercises form integral parts of the CFEV assessment framework (see below).
Overall, the aim of the CFEV assessment framework is to combine a wide range of data and expert opinion into an assessment of the conservation value of all freshwater-dependent ecosystems in Tasmania.
The scope of the audit included an assessment of rivers (including riparian vegetation), wetlands, lakes and waterbodies, saltmarshes, estuaries, karst systems and groundwater-dependent ecosystem values. Each ecosystem is considered separately and no attempt has been made to compare between them (i.e. to compare rivers with wetlands, or estuaries with lakes).
The results of the CFEV assessment are housed in the CFEV database. A comprehensive technical report , detailing the adopted methodology of the assessment framework, data limitations and results is available and supports the CFEV database.
The CFEV assessment framework
The CFEV assessment framework (shown as a flowchart below) is driven by three main components (Naturalness (N), Representativeness (R) and Distinctiveness (D)), and consisted of two key steps – the statewide audit and conservation evaluation. Every river section, wetlands, waterbody, saltmarsh, estuary and karst system in the state was 'put through' the framework in the following way to be assigned a Representative Conservation Value (RCV), Integrated Conservation Value (ICV) or Conservation Management Priority (CMP) ranking.
CFEV Assessment Flowchart
The statewide audit consisted of two assessments being conducted simultaneously. A classification was conducted to describe the pre-European physical and biological characteristics of all the ecosystem spatial units. This provided an indication of the feature's Representativeness. The condition (or Naturalness) assessment involved a range of physical and biological variables used to determine the extent to which the ecosystem feature had changed from its pre-European or natural condition.
The results of the classification and condition assessment were combined and input to the conservation evaluation. This process involved ranking each ecosystem spatial unit based on their conservation value. Conservation value was deteremined by using the results of the statewide audit in a spatial selection process to identify freshwater areas that are highly representative of its kind (as described by up to seven separate classifications), with a preference for the most natural examples. These ecosystem spatial units were given the highest Representative Conservation Value (RCV) ranking.
A second conservation value ranking was assigned to the ecosystem spatial units that took into account the presence of unique and distinct values at or near the sites (an assessment of Distinctiveness). Distinctive features of an ecosystem include a diverse assortment of 'Special Values', such as threatened flora and fauna species, important bird sites, species with important evolutionary life traits. These values were considered alongside the RCV to give an Integrated Conservation Value (ICV) ranking.
The last step of the conservation evaluation results in a Conservation Management Priority being assigned to the ecosystem spatial units. This process re-orders the conservation value rankings by including an assessment of current and future land and water management practices. For example, sites deep within National Parks are considered to be less of a priority for urgent conservation management than coastal saltmarshes on private land.
More details on what variables were used for each ecosystem theme can be found in the CFEV assessment framework summary, available here.