Saturday, May 14, 2011

BIODIVERSITY HOTSPOTS: South-West Australia and around the globe.




© Densey Clyne/Auscape
Nearly 80 percent of the plant species in Southwest Australia are found no where else in the world, 
including many of the brightly-colored members of the genus Banksia. Banksia coccinea is pictured here.






 


Last year I read a great deal about the South West corner of this continent... It made me very keen to go and see for myself some of what I was reading... like the fact that 80% of species are said to be found nowhere else in the world. I came across a wonderful book called 'Australian Seeds' which I posted on last year... and so many threads worth following up on. 
When researching on this Australian Biodiversity hotspot today I found this overview at Conservation International.


 
 
The forest, woodlands, shrublands, and heath of Southwest Australia are characterized by high endemism among plants and reptiles. Its unique vertebrate species include the numbat, honey possum, and the red-capped parrot. The western swamp turtle, which hibernates for nearly eight months of the year in response to dry conditions and hot temperatures, may be the most threatened freshwater turtle species in the world, although a successful conservation program has allowed its numbers to increase. The primary cause of habitat loss in Southwest Australia has been agricultural expansion, which is accentuated by extensive fertilizer use. A major threat for the native fauna has been the introduction of ivasive alien species like foxes and cats.


 


Hotspot Original Extent (km 2)356,717
Hotspot Vegetation Remaining (km 2)107,015
Endemic Plant Species2,948
Endemic Threatened Birds3
Endemic Threatened Mammals6
Endemic Threatened Amphibians3
Extinct Species†2
Human Population Density (people/km 2)5
Area Protected (km 2)38,379
Area Protected (km 2) in Categories I-IV*38,258
†Recorded extinctions since 1500. *Categories I-IV afford higher levels of protection.
OVERVIEW


The Southwest Australia Hotspot occupies some 356,717 km² on the southwestern tip of Australia, in the state of Western Australia. As defined, this hotspot comprises the Southwest Botanical Province, but excludes the neighboring Southwestern Interzone. As this hotspot is one of five Mediterranean-type ecosystems in the world, most rain falls during the winter months and the summers are characteristically dry. A broad coastal plain 20-120 kilometers wide grades into gently undulating uplands, with weathered granite, gneiss and lateritic formations. Further inland, rainfall decreases and the length of the dry season increases.

Native plants are well adapted to the nutrient-poor sandy and lateritic soils, which also support broadacre cropping and sheep grazing. Vegetation in the province is mainly woody, comprising forests, woodlands, shrublands, and heaths, but no grasslands. Principal vegetation types in this region are Eucalyptus woodlands, and the Eucalyptus-dominated “mallee” shrubland. Kwongan is a term adapted from the Aboriginal Noongar language to cover the various Western Australian types of shrubland, comparable with the maquis, chaparral, and fynbos of other countries with Mediterranean-type systems. The principal structural types of Kwongan are thicket, scrub-heath, and heath, which together comprise about 30 percent of the original vegetation. A number of vegetation units are endemic, including some types of eucalyptus forests and some forms of kwongan.

The Southwest Australia Hotspot occupies some 356,717 km² on the southwestern tip of Australia, in the state of Western Australia. As defined, this hotspot comprises the Southwest Botanical Province, but excludes the neighboring Southwestern Interzone. As this hotspot is one of five Mediterranean-type ecosystems in the world, most rain falls during the winter months and the summers are characteristically dry. A broad coastal plain 20-120 kilometers wide grades into gently undulating uplands, with weathered granite, gneiss and lateritic formations. Further inland, rainfall decreases and the length of the dry season increases. Native plants are well adapted to the nutrient-poor sandy and lateritic soils, which also support broadacre cropping and sheep grazing. Vegetation in the province is mainly woody, comprising forests, woodlands, shrublands, and heaths, but no grasslands. Principal vegetation types in this region are woodlands, and the -dominated “mallee” shrubland. is a term adapted from the Aboriginal Noongar language to cover the various Western Australian types of shrubland, comparable with the maquis, chaparral, and fynbos of other countries with Mediterranean-type systems. The principal structural types of Kwongan are thicket, scrub-heath, and heath, which together comprise about 30 percent of the original vegetation. A number of vegetation units are endemic, including some types of eucalyptus forests and some forms of kwongan.
Overview | Unique Biodiversity | Human Impacts | Conservation Action




Home to majestic trees that seem to stretch forever
and wildlife such as kangaroos, the South West region
 is popular with nature enthusiasts including hikers.

 Map from ANU E Press article: ‘Plants That Perform For You’?
From Floral Aesthetics to Floraesthesis in the Southwest of Western Australia
John C. Ryan

Gregory Pryor - BLACK SOLANDER:  Black Solander was an attempt to take a snapshot of the entire census of Western Australian plants. The biodiversity hot spot of Western Australia (particularly the south-west) hosts over 12,000 species (and still counting). The systematic identification of these plants simultaneously achieves two things: It continually expands the number of new species found in this remarkable region of the world and at the same time catalogues the rapid demise of other species through various man made causes. This exhibition proposes the idea of a herbarium as a mausoleum. Instead of specimens however,  10,500  small ink drawings were painted from the dead plants in the Western Australian Herbarium. And contrary to the traditional practice of botanical illustration, the use of black ink on black sugar paper  blurred specificity and suggested a more shadowy archive. The artist  faithfully echoed all elements of a specimen sheet: naming, dating, mounting devices, collection stamps and the dark, ghostly silhouette of the plant. Through this process the plants were reinvented, and the collection was reborn in another context.

Black Solander installation shot
Black solander, 2005, ink, graphite and spirit based ink on sugar paper.
                                                                       Pryor is represented by Lister Gallery



Greg Pryor
Gregory Pryor: Black Solander, 2005

Read more here:

Black Death: Species Extinction in WA

Author & Artist: Mr Gregory Pryor, feature





THE BIODIVERSITY HOTSPOTS - THE following text is from the Australian Government Department of Sustainability,  Environment,  Water,  population  and communities.
Read more here.

What is an international biodiversity hotspot and how were they identified?

Conservation International, a nonprofit environmental organisation based in Washington DC, has identified 25 international biodiversity hotspots, including the southwest of Australia.
These international hotspot areas were assessed according to their plant diversity, and had to contain at least 1500 endemic plant species to qualify. All of the regions identified had lost more than 70% of their original habitat.

Where are the international biodiversity hotspots?

25 international biodiversity hotspots have been identified. Hotspots have been identified in:
  • North and Central America (3 hotspots)
  • South America (5 hotspots)
  • Europe and Central Asia (2 hotspots)
  • Africa (5 hotspots)
  • Mainland Asia (3 hotspots)
  • Asia-Pacific (7 hotspots - including Southwest Australia)




6 comments:

SOEWNEARTH said...

and just think we own 36acres of that as conservation covenanted wetlands half way between Denmark and Walpole.

Sophie Munns said...

Well I must say... that sounds pretty amazing... what are you doing living at the other end of the country?

I'd love to go see that corner of this land!
S

Maggie Neale said...

Biodiversity hotspots...I like thinking about that. Fabulous tall trees and the word "damplands" draws me in. We've got damplands here with all the rain.

Sophie Munns said...

Good to hear from you Maggie.... much to think of around this topic I totally agree.
S

Donna Heart said...

so so interesting Sophie, thank you for this wonderful information. I have skim-read it and will go back and read those links again more thoroughly. South of Gerladton where I live is an absolutely gorgeous part of the world - the Alexander Morrison National Park. I heard a friend say it is one of the most diverse areas of flora (in OZ or the world???) I drive through the heathlands often and in spring just marvel at the biodiversity. here's a little bit of info here: http://www.dec.wa.gov.au/component/option,com_hotproperty/task,view/id,115/Itemid,755/ I think I need to research that and see if it's true though ;) And yes, there's no need to argue about it - book yourself a ticket to the south west/mid west for august or sept ok!!!

Sophie Munns said...

I wasn't sure where you were based now Donna...I remember you had lived up north!
Beautiful part of the world ... I certainly will put it on the wish list... some of my family visited in November last year and had a brilliant time... it would be great to do it in spring.
I think "in the world" is correct... I read somewhere one of the ten top spots in the world.. and the geological history is hugely fascinating!
Have you seen that book Donna?
and have a wonderful show wont you!
S

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