Find further information on the Conservation of Freshwater Ecosystem Values (CFEV) Program and its data at www.dpipwe.tas.gov.au/cfev.
TitleWillows
CustodianWater and Marine Resources Division, Department of Primary Industries, Parks, Water and Environment
CreatorRod Knight, GIS Services
GIS Unit, Information and Land Services Division, Department of Primary Industries and Water
DescriptionPresence and absence of willows within river riparian zones
Input data
Lineage
The willows data layer was developed from distributional information derived from a National Heritage Trust project carried out through the TCT. Information regarding the distribution of willows within Tasmania was sourced using expert knowledge through a series of workshops (Farrell 2003). The data collected through this project had been categorised into varying condition classes, with a high level of subjectivity. There was also a lack of consistent information on low to medium density infestations across the state. The data was therefore transformed to indicate only a presence/absence of willows along rivers and was assigned to river sections using the rules described below.
Data limitations
The willows spatial data layer is believed to indicate the locations of the majority of significant willow infestations as at 2004. It does not comprehensively describe the distribution of willows in Tasmania.
Date createdSeptember 2004
Scale and coverage1:100 000; Statewide
References
Farrell, B. (2003). Strategic planning for willow management in Tasmania. Tasmanian Conservation Trust, Hobart.
TitleWillows
Column headingRS_WILLOW
Input data
Type of dataCategorical
Number of classes2
Assigning values to ecosystem spatial units
Using the derived willow infestation distribution data layer, each river section was assigned a score indicating a dominant presence (0) or absence (1) of significant willow infestations (RS_WILLOWS) for the river section length.
CFEV assessment framework hierarchy
Rivers>Statewide audit>Condition>Naturalness score (RS_NSCORE)>Biological condition (RS_BIOL)>Native riparian vegetation (RS_NRIPV)