Triodia scariosa
Triodia scariosa | |
---|---|
Triodia scariosa depicting annular growth ring with inflorescence | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Clade: | Commelinids |
Order: | Poales |
Family: | Poaceae |
Genus: | Triodia |
Species: | T. scariosa
|
Binomial name | |
Triodia scariosa N.T.Burb
| |
Occurrence data from ALA[1] [citation needed] | |
Synonyms[2] | |
Species synonymy
|
Triodia scariosa, is more commonly known as porcupine grass or spinifex (not to be confused with
Evolutionary relationships
Triodia scariosa can be accurately traced back to the order Poales (Grasses, sedges and their relatives).[9][10] Poales are found globally and represent one third of moncotyledons (~20,000 species), and approximately 7% of all angiosperms.[10] Poales branch away from other monocotyledons in the late cretaceous (>65 million years ago)[9] and can be identified by three gene sequences (rbcL, atpB, and 18S rDNA).[10] In this order, Poaceae (grasses) form the largest family[10] which are recognised by their branching growth pattern (where shoots follow a consecutive branching order).[5][11] Poaceae are phylogenetically linked to South America and Africa, Australia's break away away from Gondwana ~35mya is thought to have influenced the evolution of the graminid clade that is predominantly found in Australia.[10]
The
Distribution
Conservation status
Triodia scariosa is common, and currently not listed as threatened at state or national level.
Ecology
Throughout its range, T. scariosa is a
Vegetation species associated with T. scariosa are associated with its distribution within its range and the regions climate.[3][7] In the arid zone, it co-occurs with other Triodia species, and is also associated with Acacia, Corymbia, and Eucalyptus woodland.[3] In the southern aspect of its range, it is most commonly associated with an overstory dominated by Mallee Eucalypts (Eucalyptus dumosa and E. socialis),[17] but also Callitris, Melaleuca, Acacia and Hakea.[7] T. scariosa distribution is associated with soils that are low in available water and nutrients [21] and the extensive root system provides mechanical support for soils, reducing the loss of the thin aeolian topsoil layer.[5][21]
Triodia scariosa contributes to the fire ecology of a landscape, as the dry fuel load from ageing individuals in the landscape increases in mass in the time since fire before plateauing and declining .[17][21] In the Murray-Mallee, wildfires are large (1000's ha), burn at both high and uniform severity and connection through the landscape is provided by the continuous fuel source of T. scariosa, resulting in top kill of the low canopy tree species.[17] In this landscape, all vegetation is removed following fire, and regeneration is uniform and predictable, including the presence of fauna species.[17] The interval between wildfire in this ecosystem is associated with regeneration of T. scariosa over time, and its accumulation of dead core material, which (under suitable climatic conditions) promotes and sustains wildfire in the landscape.[17][21] This is usually possible at a minimum interval of 10–20 years post fire, peaking at ~20–30 years, but if rainfall has been high it can be within 2 years.[17][21][22]
Life history traits
Regeneration of T. scariosa is heavily linked to rainfall and fire.
Growth of T. scariosa occurs via stolons, which expand outward from its centre as the plant ages.[5] The size and complexity of individual plants is influenced by time since fire, environmental factors (soil, ecological relationships) and climate variables.[14][17][19][22] T. scariosa's C4 photosynthetic pathway supports higher growth rates and water use efficiency at higher temperatures, and growth is enhanced with summer rainfall.[14] In the first few years post-fire, T. scariosa cover increases relatively rapidly, peaks at ~30 years, then declines slowly over subsequent decades.[17] It has been suggested that T. scariosa requires >20 years between fire interval for individual plants to mature, and establish seed-banks and habitat complexity before fire returns to ensure suitable levels of regeneration in the landscape.[19][22]
A notable feature of T. triodia is the annular growth ring that forms with age. As the plant ages, it grows outwardly in ring or crescent form, and the old growth dies off in the centre.[5][6] These features can grow up to 3m in diameter and individuals may join to form reef-like patterns in the landscape.[5][6] The rings are uncommon in the first 20–30 years post-fire, but peak at ~55 years, before the plant senesces over the following decades.[17][22]
References
- ^ "ALA | Login". auth.ala.org.au. Retrieved 21 October 2022.
- ^ "Triodia scariosa N.T.Burb. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 21 October 2022.
- ^ a b c Department of the Environment and Energy (2017). "NVIS Fact Sheet: MVG20 - Hummock grasslands" (PDF). Retrieved 14 October 2022.
- S2CID 105936760.
- ^ a b c d e f g h i Australian National Botanic Gardens, Parks Australia. "Triodia scariosa - Growing Native Plants". www.anbg.gov.au. Retrieved 2022-10-21.
- ^ S2CID 84441427.
- ^ a b c Department of Environment and Energy (2017). "NVIS Fact Sheet: MVG14 - Mallee woodlands and shrublands" (PDF). Department of Climate Change, Energy, the Environment and Water. Retrieved 19 October 2022.
- ^ "NVIS Fact sheet MVG 20 – Hummock grasslands" (PDF). Australian Government | Department of Climate Change, Energy, the Environment and Water. Retrieved 21 October 2022.
- ^ ISSN 0024-4074.
- ^ PMID 12206239.
- ISSN 0367-2530.
- ^ a b c d e f Anderson, B. M. (2016). "Systematics and evolution of the Triodia basedowii species complex (Poaceae: Chloridoideae)" (PDF).
{{cite journal}}
: Cite journal requires|journal=
(help) - )
- ^ ISSN 1442-9985.
- ^ "Seeds of South Australia - Species Information". spapps.environment.sa.gov.au. Retrieved 2022-10-15.
- ^ Office of Environment & Heritage (19 October 2022). "Porcupine grass – Red Mallee – Gum Coolabah hummock grassland/low spare woodland in the Broken Hill Complex Bioregion – profile". NSW Department of Environment and Planning. Retrieved 19 October 2022.
- ^ ISSN 2296-701X.
- ^ S2CID 219513298.
- ^ S2CID 248605149.
- S2CID 84146806.
- ^ ISSN 1036-9872.
- ^ )
- ISSN 1442-9985.
- ISSN 1036-9872.