Dryland salinity

[ICPS-bob]

In Australia, nearly 5.7 million hectares are considered at risk or affected by dryland salinity -- a figure that could triple to 17 million hectares in 50 years time.

What effect has increasing salinity had on CP populations? Anyone know???

[pinglover]

I know very little of the problems currently facing the Aussies other than that this is being perceived as a major cause for concern and there is a scramble to re-establish native deep-rooted vegetation. Sound familiar? My limited knowledge of this situation is that the lands were stripped of the native vegetation for agriculture and as a result, the underground water table is rising to the surface. Many plants aren't salt tolerant. Just a wild guess but I suspect CP populations are already being negatively impacted. Looks as if they have a major hydrological imbalance and you would be best to comment on this.

I just did a quick search and came up with these websites-
abc.net.au/learn/silentflood/
www.ndsp.gov.au/
cyllene.uwa.edu.au/~dpannell/dppubnrm.htm

I don't have time to read them right now though I'd like to since your brought it up.

[ICPS-bob]

Yes. I am well acquainted with the problem. I was in Australia a few years ago consulting with managers on the likelihood of reversing the problem through landscape-level vegetation management. However, I would like some first-hand information on what has been happening to CP populations.

[matti]

admin said:

In Australia, nearly 5.7 million hectares are considered at risk or affected by dryland salinity -- a figure that could triple to 17 million hectares in 50 years time.

What effect has increasing salinity had on CP populations? Anyone know???

Hi Bob, I am not awear of anywere around here with salinity problems, I think it happens more out west were the water table has risen then the drought has come along and left the salt on the top of the soil, I think the only plants at risk are Drosera burmannii and indica.

[Sean Spence]

Most problems would be occurring over in the west and I'm not familiar with any of those. In my parts, the major areas of salinity are a reasonable distance inland where few CPs grow.

There are a few local areas affected which are currently being revegetated with salt-tolerant species of tree and shrub and I've found colonies of D. peltata var. foliosa and D. glanduligera amongst them. They don't appear to be suffering at all.

I'd be interested to hear if any of the inland tuberous Drosera species of WA are being affected.

[chug]

Most of the area's I know of are around the River Murray where there has been intense irrigation over the years. No idea if any plants have been touched by it, but it is possible down southish. If I find anything, ill let you know.

[BarryRice]

Hey Bob,

I saw some examples of the rising water problems when I visited Kangaroo Island, Australia, many years ago. The area was facing rising water because it had a lot of its eucalypts cut down.

Lots of Drosera occur on Kangaroo island.

[matti]

We've had over two inches since Sunday.

[wadave]

Hi Bob,

I've lived in South Oz for the first 20 years of my life and saltation was a very real issue there, we studied it at school in geography and it was on the news quite a bit.

I've been living in WA since '95 and I've noticed saltation is quite an issue here too.

Both states tend to have saltation around the agricultural areas where the natural vegetation has been removed and irrigation is high.

As CP's occur mostly in native bush areas I would tend to think that the local populations have been relatively spared saltation, though I've not got any empirical data to back this up.

I merely suggest this to be the case as the native bush land areas are relatively undisturbed and the natural balance tends to be intact.

Possibly areas of bushland that boarder farmland would experience a rise in the local water table and therefore experience a problem with salt.

I hope this helps with your query.

Dave.

[Richard Davion]

KI is Extremely Salty around the, 'Narrow', America-River Region ... Plenty-of-Samphire to be Seen and Photographed. The Whole Middle-of-The Island Contains Swades of Drosera-planchonii.

Kangaroo-Island's Flora is Renown for Having species-links with Both The South-West of Western-Australia and Tasmania. Adenanthos-sericea that Grows Around The Albany-Region is also Native to KI but Does-not Grow on The Fleurieu-Peninsula of The- (Adelaide)-Mainland. >(*~*)< Bizarre, ... but it Does Support the Southern-Landbridge Theory of Species Migration across the Southern-part of This Vast Desert-Hearted Continent before the The Sealevel rose 100-Feet cutting-off KI from The-Mainland and producing the Reserche-Islands off the WA Mainland.

The-Grampians in-Victoria Reputedly Contain the Westernmost outpost of Telopea or 'Warrahtar' more-normally Associated with The-Blue-mountains of New-South-Wales and Stokes-Inlet in the South-West of WA Contains the Recently-Discovered Single-Fork Version of Drosera-binata Suggesting that Species-Migration Can Quite-Often Go Either-way.

Although The Duplex-soils of KI are basically Laterite [South-East End] or Limestone [North-West End] There's a Band of Orpholitic Serpentine that Runs as a Spine Down the Fleurieu-Peninsula Across Backstairs-Passage and onto the North-Western tip of Dudley Peninsula which is Basically The 'Head' or Landmass to the Right of The American-River Region.

The two Types of Soil basically mix in a Giant Slant as you Head West across the Island on the East-West Highway with Apparently a CP-'Hot'-Spot Around the Mid-North-West of Flinders-Chase National-Park Down into the Park off the North-South 'Highway' (Road) that Basically is the Eastern-Border of The-Park.

As far-Back as the Late 1970s Posters of The Plants of Kangaroo-Island included a Pictorial Representation of Drosera-ramellosa (a western-Australian species) ... The most noteable-of These on The-Wall of The Passage-Way of The Old State-Herbarium of Adelaide, South-Australia!!! >(*~*)<

Recently Drosera stolinofera ssp purpurescens has been Discovered in The Albany-Region of WA. The Question Remains as to Whether-or-Not Drosera-ramellosa Truly 'Exists' on The Island or it is a remnant-form of a Branch of The Stolonifera-Complex or indeed Whether Drosera-whittakerii and its Variations that occur on The-Island are actually a Divergent-Branch of The Stolonifera-Complex or something separate?

Drosera praefolia that Also Occurs on The-Island at Lake-Ada as Well as on The Fleurieu-Peninsula of The-Mainland could-be 'Considered' a Remnant of the Rosulata-Bulbosa Group of Western-Australia!?

If Someone were to Find a 'Disjunct'-Colony of Cephalotus Deep in The Heart of Flinders-Chase or on The very-'Tip' of The Eire-Peninsula I-Would not be 'Too'-Surprised for The Soils of These Two-Regions are Supposedly Related and Once Connected.

As an Aside Recent Reading has Suggested that Cape-Le-Grande 'Might'-be an-area to look for Further Colonies of Cephalotus as-well, ... Since it also has These 'Weird'-Affinities to Other Areas of Australia. It 'May' Actually Have been the Original Collection-site for The-Species for They were Blown-off Course by a Squall to This Region. >(*~*)< / >(*U^)<

Australia is The-'Saltiest' Continent on The-Planet with The-Most CPs ... Species and Groupings / Forms surrounded by Vast Tracks of Coastline and 'Coastal'-plains ... so-Flat in Parts that We-have be Inundated by Vast Inland Seas at-Least Thrice, ... Resulting in Australia having The Largest Salt-Lakes in The-World.

Peter-Craeger's Comments, in an Early-Edition of The Queensland Newsletter: "Carnivore", Mentioned that Drosera-petiolaris grows Quite Happily in Mangrove-mud on The More 'Fresh'-than-Salt-Side was Quite an Eye-Opener.

Apparently The-Connection is a Halophytic-Mycorrhiza that Requires Salt to be present to Grow but the Salt has to be 'Bound', Not-Free, to Cation-&-Anion Exchange Sites in The Soil Which are Set-up via The Attack of 'Bound'-Hydroxyl-ions [ie Non-pH Influencing] by The Exudates of The Very-(often)-Sclerophyllous-Flora itself.

ie Salintiy is actually the Solution of The Australian Flora - Man-has just turned-it into a Problem by Callously-clearing The-Land of its Native-(Ameliorating)-Covering.