Glossary for BioCondition benchmarks
Benchmark
A description of a regional ecosystem vegetation community that represents the median or average characteristics of a mature and relatively undisturbed ecosystem of the same type.
Canopy
The layer formed collectively by the crowns of adjacent trees (or shrubs in the case of shrublands). It may be continuous or discontinuous. The canopy usually refers to the ecological dominant layer (EDL). Assessed as the percentage cover of opaque crowns.
Coarse woody debris
Coarse woody debris or fallen dead timber located on the ground. Assessed as the total length in metres of woody debris that is > 10cm diameter and > 0.5m in length (and more than 80% in contact with the ground).
Cryptogam
Collective term which includes algae, ferns, fungi, lichens, liverworts, mosses and hornworts
Diameter at Breast Height (DBH)
A measure of the size of the tree and is consistently measured at 1.3m from the ground. On sloping ground, DBH is measured on the high side of the tree from bare earth ground level. Ensure that the tape is horizontal or at a tangent to the trunk when reading the diameter. On leaning trees, on level ground, 1.3m is measured from the underside of the lean. If a whorl, bump scar or other abnormality occurs at the 1.3m mark, measure the diameter at a nominated height (measured in whole 0.1m increments) above the defect. If a representative measure as described above cannot be taken (e.g., presence of strangler figs), a reasonable estimate of the diameter should be made viewing the tree from two different directions. For multiple stems, a diameter is recorded for each stem, when it divides below 1.3m.
Dominant species
A species that contributes most to the overall above-ground biomass of a particular stratum (= predominant species).
Ecologically dominant (predominant) layer or species (EDL)
The layer or species making the greatest contribution to the overall biomass of the site and the vegetation community.
Emergent layer
The tallest layer/stratum is regarded as the emergent layer if it does not form the most above-ground biomass, i.e.. the EDL, regardless of its canopy cover e.g., poplar box (Eucalyptus populnea) trees above a low woodland of mulga (Acacia aneura).
Eucalypt
Under BioCondition, a eucalypt is any species from the following genera: Eucalyptus, Corymbia, Angophora, Lophostemon, and Syncarpia.
Forb
Herbaceous or slightly woody, annual or sometimes perennial plant; not a grass or life form defined under Other species.
Grass
Any plant of the family Gramineae or Poaceae, characterised by jointed stems, sheathing leaves, flower spikelets, and fruit consisting of a seed-like grain or caryopsis (true grasses). Includes the following plant life forms:
Tussock grass: forms discrete but open tussocks usually with distinct individual shoots, or if not, then forming a hummock. These are the common agricultural grasses.
Hummock grass: coarse xeromorphic grass with a mound-like form often dead in the middle; genus Triodia.
Other grass: member of the family Poaceae but having neither a distinctive tussock nor hummock appearance.
Grassland RE
A remnant Regional ecosystem (RE) described as having a structure category of grassland in the Regional Ecosystem Description Database.
Ground cover
Ground cover is assessed as projected foliage cover of the native plant ground cover (grasses, forbs, low shrubs, cryptogams and seedlings) and non-native plant cover. Note that the sum of the plant ground cover (native and non-native), organic litter, coarse woody debris and bare ground/rock in a quadrat will equal 100%. .
Large tree
A living tree identified as ‘large’ by a DBH threshold as defined in the benchmark document relevant to a regional ecosystem. In some regional ecosystems a different large tree threshold will be identified for eucalypt and non-eucalypt species due to the variation in potential size of these two tree types. Eucalypts include trees of genera Angophora, Eucalyptus, Corymbia and Lophostemon. If a large DBH threshold is not provided in the benchmark document, then generic thresholds of > 20cm DBH for non-eucalypts and > 30cm DBH for eucalypts can be used.
Native plant
A plant taxon that has evolved in Queensland unaided by human intervention or has migrated to and persist in Queensland unaided by human intervention. This does not include taxa that are naturalised to Queensland or a particular bioregion. Brown and Holland (2020) lists plant taxa that are accepted as native to Queensland.
Native plant species richness
For BioCondition assessment, species richness refers to the number of species recorded in the assessment area from four life form groups (tree, shrub, grass and forbs and other).
Non-eucalypt
Under BioCondition, a non-eucalypt species is defined as any species that is not listed as a eucalypt.
Non-native plant
A plant that is not native.
Non-remnant vegetation
Non-remnant vegetation is vegetation that fails to meet the structural and/ or floristic characteristics of remnant vegetation. It may include regrowth, heavily thinned or logged and significantly disturbed vegetation, and cleared areas. Non-remnant vegetation may retain significant biodiversity values and includes areas mapped as ‘high-value’ regrowth.
Organic litter
Includes both fine and coarse organic material such as fallen leaves, twigs and branches < 10cm diameter
Other life forms and plant groups
Sedge: herbaceous, usually perennial erect plant generally with a tufted habit and of the families Cyperaceae and Restionaceae.
Rush: herbaceous, usually perennial erect plant. Rushes are grouped into families Juncaceae, Typhaceae, Restionaceae and the genera Lomandra and Dianella.
Fern and fern allies: characterised by large and usually branched leaves (fronds), herbaceous to arborescent and terrestrial to aquatic; spores in sporangia on the leaves.
Bryophyte: mosses and Liverworts. Mosses are small plants usually with a slender leaf-bearing stem with no true vascular tissue. Liverworts are often moss-like in appearance or consisting of a flat, ribbon-like green thallus.
Epiphytes: (including orchids), mistletoes and parasites. Plant with roots attached to the aerial portions of other plants. Often could also be another growth form, such as fern or forb.
Lichen: composite plant consisting of a fungus living symbiotically with algae; without true roots, stems or leaves.
Vines: climbing, twining, winding or sprawling plants usually with a woody stem. Herbaceous sprawling plants e.g., Boerhavia spp., most Ipomoea spp. are included in forbs.
Aquatic: plant growing in a waterway or wetland with the majority of its biomass under fresh, saline or brackish water for most of the year.
Perennial grass cover
The average percentage cover of native perennial grasses. The cover is measured by a vertical projection downwards of the living and attached plant material.
Perennial species
Perennial species are long-lived plants, tending to persist for three or more years. Generally perennial grasses are characterised by larger bulk than annual grasses i.e., forming tussocks and large root mass with evidence of previous seasons growth i.e., remains of last year’s tiller bases, and presence of stolons or rhizomes.
Recruitment of dominant canopy species
Proportion of dominant canopy (ecologically dominant layer) species with evidence of recruitment.
Reference site
A site that represents an example of a Regional ecosystem (RE) in its reference state, i.e. the natural variability in attributes of an ecosystem relatively unmodified in the contemporary landscape. As not all RE’s will have examples of totally unmodified states, reference sites represent the “Best On Offer” reference state for that RE in a local area. Data obtained from reference sites are used to establish benchmarks for each of the attributes used within BioCondition
Regional ecosystem (RE)
Vegetation communities in a bioregion that are consistently associated with a particular combination of geology, landform and soil. For descriptions of regional ecosystems go to the Regional Ecosystem Description Database.
Remnant vegetation
Remnant vegetation is defined as vegetation where the dominant canopy has greater than 70% of the height and greater than 50% of the cover relative to the undisturbed height and cover of that stratum and dominated by species characteristic of the vegetation’s undisturbed canopy.
Shrub
Woody plant that is multi-stemmed from the base (or within 200mm from ground level) or if single stemmed, less than 2m tall. (The shrub stratum may contain recruiting canopy species.)
Shrub canopy cover
The estimation of the percentage canopy cover of the living shrub layer (see Shrub). Assessed as opaque crowns.
Stratum
A layer in a community produced by the occurrence at approximately the same level (height) of an aggregation of plants of the same habit (Beadle and Costin 1952).
Subcanopy
A distinct vertical layer of shorter trees that occurs beneath the canopy layer. Assessed as the percentage cover of opaque crowns.
Tree
Woody plants, more than 2m tall with a single stem or branches well above the base.
Tree canopy cover
Refers to the estimation of the percentage canopy cover of the living tree layer (see Tree).
Tree canopy height
The median canopy height in metres, as estimated for the tree layer (see Tree canopy cover).
Typical species
Are those species that characterise the regional ecosystem, community or stratum