What is BioCondition?
BioCondition is a vegetation condition assessment framework that provides a measure of the capacity of a terrestrial ecosystem to maintain biodiversity values at a local or property scale. It is a site-based, quantitative and repeatable assessment procedure that provides a numeric score that reflects functional through to dysfunctional vegetation condition states for biodiversity. In BioCondition, we refer to vegetation condition as the relative capacity of a regional ecosystem to support the suite of species expected to occur in its reference state. The reference state refers to the natural variability of the stable land-based vegetation state that is mature and relatively long undisturbed in the contemporary landscape and in ‘Best-on-Offer’ condition.
The primary components of the BioCondition framework include:
- The assessment unit, which is based on regional ecosystems by broad condition states (remnant, high-value regrowth, non-remnant).
- A suite of vegetation condition attributes that are based on a pressure-state-response conceptual framework and are direct or surrogate measures of species diversity and/or ecological processes.
- Benchmarks for each of the vegetation attributes for each regional ecosystem
- A scoring system that provides a condition metric that is comparable between and within ecosystems over space and time.
Benchmarks provide the objective comparison of vegetation condition states within and between regional ecosystems. They are quantitative values for each assessable attribute in BioCondition, and are derived as the average or median values from field data collected from reference, or Best-on-Offer, sites in the contemporary landscape, during optimal seasonal conditions as practicable. For rare and highly disturbed regional ecosystems, expert elicitation is used to determine benchmarks.
Benchmark documents have been developed by the Queensland Herbarium and are available on-line for a subset of described regional ecosystems. Where benchmarks are currently not available, the reference site manual provides a method for the derivation of benchmarks for the BioCondition framework.
The recommended approach is to locate and assess a local reference site using the reference site assessment protocol at the same time as the BioCondition assessment. The information obtained from the local reference site can be used to augment and refine the range of benchmark values for each attribute relative to the site being assessed, by accounting for excessive variability that could be caused by seasonal or drought effects, particularly for the attributes:
- Tree canopy cover
- Shrub canopy cover
- Grass cover
- Species richness for the shrub, grass and forb and other life form groups
The BioCondition manual provides an assessment protocol that gives a measure of how well an area of vegetation is functioning for the maintenance of biodiversity values. The assessment protocol works in conjunction with regional ecosystem benchmarks, which can be downloaded if available or derived from reference site assessment if not. A datasheet is provided.
The reference site manual provides an approach for obtaining Benchmarks if they are currently not available, or for when sampling needs to occur in non-optimal seasonal conditions. A datasheet for use with the manual is provided.