Malcolm Turnbull, the Federal Parliamentary Secretary for water, recently announced a $13.4 million grant to revive the Macquarie Marshes and other important wetlands.
But it is unclear how the money will be spent. Reference has been made to ‘plans’, ‘models’, ‘competing interests’, ‘drought’, ‘market mechanisms to recover water’, and ‘noxious weeds’.
But more money, more plans, more water won’t necessarily save the marshes.
There has been much discussion at his blog about the relative impact of drought, levies, grazing and cotton since I first visited the marshes in October last year.*
I have come to the conclusion that the marsh environment would benefit most from the following actions which were detailed in a blog post entitled ‘Three Pressing Issues for the Macquarie Marshes’:
1. Bulldoze the levy banks which are channeling water away from the two nature reserves and onto private land,
2. Protect key bird nesting sites from trampling by cattle.
3. Reduce the risk of overgrazing perhaps through some agreement about stocking rates and grazing regimes.
These actions would not be popular locally or easily understood in Sydney, but they would make a difference on the ground and they wouldn’t cost a lot of money.
Chris Hogendyk, an irrigator and chairman of Macquarie River Food and Fibre (MRFF), sent me a note following the $14.3 million announcement. He recommends that more land be purchased and converted to nature reserve:
“Both the Macquarie Marshes and Gwydir Wetlands are iconic wetlands valued internationally and by the local community.
… It is overly simplistic during a drought of record proportions to simply call for more water to solve the problems that face these important wetlands.
… 90% of the Marshes are in private hands which means 90% of any purchased water will be used for little more than grazing.
As a taxpayer I do not think that funding the purchase of water under these conditions will achieve a good environmental outcome.
In fact, more water delivered simply means more cattle and that in turn leads to further degradation of the environment.
MRFF has no problem in principle with the Government purchasing water from willing sellers to be used for the benefit of the environment, but we do object the Government purchasing water from one stakeholder group and delivering it to another stakeholder group free of charge.
MRFF proposes that a much better solution would be to purchase key land area within the marshes to protect this environment from grazing and hence get much better environmental value from the water there today.”
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* Blog posts on Macquarie Marsh issues:
1. Cattle killing the Macquarie Marshes, 21October 2005
http://www.jennifermarohasy.com/blog/archives/000949.html
2. Marsh Graziers Don’t Pay for Water, 25 October 2005
http://www.jennifermarohasy.com/blog/archives/000958.html
3. More Water Won’t Save the Macquarie Marshes, 28 March 2006
http://www.jennifermarohasy.com/blog/archives/001282.html
4. But Reed Beds Need Water!, 12 April 2006
http://www.jennifermarohasy.com/blog/archives/001309.html
5. Three Pressing Issues for the Macquarie Marshes, 13 July 2006
http://www.jennifermarohasy.com/blog/archives/001481.html
6. Banking in the Macquarie Marshes: More Photographs & A Map, 17 July 2006
http://www.jennifermarohasy.com/blog/archives/001486.html
7. Fewer Trees Means More Water for Macquarie Marshes: Ian Mott, 23 July 2006
http://www.jennifermarohasy.com/blog/archives/001497.html
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Jennifer I have no argument with your 3 points, BUT to put forward a valid, objective case you must add an additional point:
Carefully monitor and manage levels of water extracted/diverted for irrigation to ensure adequate flows.
Choose your preferred wording so you’re not implying that irrigators haven’t already made enought sacrifices (as discussed in earlier posts). You might say that you excluded irrigation because you don’t think it makes the top 3, (and might say because you lean on the side of the irrigators), but regardless, without including it, graziers and greenies will both object, plans will fall under bun throwing and no progress will be made. Besides which, irrigators are important stakeholders and need to be actively involved.
4 pressing issues please! With all the noise, irrigation is clearly one of the top pressing issues regardless of whether or not it is actually a major cause of the current state of the marshes.
This is all a bit premature because no steps should be taken until the historical range of pre-settlement and pre-clearing innundation events are known. This is the only platform from which any legitimate duty of care can be based.
And adding more reserve is the least effective method of all because these places are never managed in the same manner as the previous 40,000 years of firestick farmers. They are an ecological abomination, of questionable habitat value, and of even less nutrient value. The wildlife won’t even eat reserve vegetation in a serious drought because it is indigestible.
But as far as the parkies are concerned they provide good photos to scare the kids and demonise the farming neighbours. The wildlife, especially ‘roos, are still eating the private pasture to the ground long after the stock have been taken off.
I see Chris Hogendyk saying, “.. during a drought of record proportions ..”
I wonder what evidence you rely on to state this Chris ?
I see Malcolm Turnbull also includes drought as a cause of “severe ecological stress”.
Ian I read your blogs about water shed in catchments.
I think you have some very valid points about changed water shed, due to land modification in the catchments. I always strongly suspected this was the case, long before I read your blogs about it, but you certainly put a strong case forward.
However I’m really not sure I believe you that this would be the case in the high rainfall mountain ecosystems where forests create their own climatic influence and any extra grazing or fire or logging would lead to “drying out” which would then require more rain before saturation point is reached.
In the drier areas I think dense regrowth would increase runoff by creating more bare ground. it is grassy vegetation that absorbs rainfall in lower rainfall areas and it doesn’t matter a stuff if there are multiple tree trunks, the water will still run off in heavy rain.
Of course the typical type of rainfall would come into play. In the south where there are usually regular lighter showers, runoff would usually not occurr untill the soil has reached saturation point, but in northern areas, heavy thunderstorms on bare ground would run-off long before soil saturation has occurred.
When I see artificially dense regrowth in dry areas, it is almost always accompanied by scald erosion and gully erosion; These are sure signs of increased runoff.
It seems pretty bizarre to me that you argue that dense woody regrowth causes erosion, but in the next breath argue that it decreases runoff??
Maybe you need to be more specific about the type of regrowth and the location in which it is growing before you always throw it in as the cause of every hydrological problem in Australia.
I think you are absolutely right about there being more run-off in some area and less in other, but I don’t believe it’s comming from where you think it is comming from.
Don’t underestimate the effects of perennial pasture improvements and upper catchment dams on reducing runoff.
And don’t underestimate the run-off effect of bare ground from cultivation, drainage schemes, dense regrowth in dry ecosytems, overgrazing, gully erosion, road creation and concrete jungles.
I too have been pondering the extra trees = less runoff issue. What’s the difference between trees and grass – trees can tap deeper water or water that has drained past the root zone of grasses – say 1.0-1.5 metres in vertosols.
Perhaps there is an interaction between the intensity or pattern of rainfall and what happens. The other issue is soil depth. Many mountainous or hilly regions have fairly shallow skeletal soils with low water holding capacity. So how much deep water is there for trees to play with?
Need some large scale field studies.
Hi Jennifer,
I work on problems similar to that of the Macquarie marshes in developing a sound commercially viable approach. Before the commonwealtn closed the fishing fleet down there was considerable interest from industry in contracting streamside vegetation and estuarine wetlands for fish production.
Staring in the lower sections of a given catchment the water users, agricultural, domestic and industrial pay those upstream to fence drainage lines and reflood wetlands. The baseline price is the local commercial agistment, lease price per hectare per annum with bonuses for the indigenous cover and its age.
(Consumers in the city could and should also be directly involved, buying products with an environmental levy – like how people pay double for dunny paper that is recycled – there is a market. So far consumers pay for farm produce but there is no opportunity to pay farmers to manage wetlands or streamsides)
There are about 1 million domestic consumers of water from the Murray Darling system alone – and they also rely on the same system to absorb their sewerage – so there is a considerable investment base.
As more land is dedicated to filtering water and creating dry time dew fall, accessing permeable layers to recharge through root growth, shading streams and filtering waste and silt – less water is required for agricultutre.
The opposition to this approach usually first comes from greens who see putting a commercial value on natural vegetation – bush – as a crime – and then from economists that are equaslly convinced that bush’s only value is aesthetic and its only measurable value a contingent one.
Marginal farms or more accurately the marginal parts of farms represent the best investment – but farmers get to stay – we need their knowledge of the land.
Investing indigenous vegetation restoration has another advantage. It grows faster and more reliably for a given area that it is pre adapted to that any other vegetation type.
In areas devoid of indigenous seed even weeds will hold ground and provide a measure of filtration until either floodwaters/birds etc deliver seed – on indeed a farmer looking to increase the payments.
Mr Turnbull like many others is stuck with a non varying water quota system over allocated to create trading. By creating a value on a volume that is inestimable it will likely be impossible to buy/afford to buy environmental allocations for places like Macquarie marshes. Because an environmental allocation is not pumped or measured it is necessarily what remains. Likely bugger-all in common parlance.
We may not be able to affect the rainfall but we can certainly retain water in the catchment longer as larger areas permeable aquifers are accessed by roots of trees,.shrubs and plants from land contracted for vegetation management.
Or can we affect rainfall? Certainly where I live in South Gippsland a foothill forest of Tasmanian Blue-gum and Mountain Ash giants generated 100-120 inches per year up until the turn of the last century and now makes barely half that.
The economic model that aggressively dominates and limits research horizons see some Armageddon type collapse for the entire system with market forces grasses somehow miraculously selecting for farmers to shift to ‘deep rooted grasses’ rising from the ashes.
There desperately needs to be another conversation that does not shy from allocating a measurable variable economic value on existing Indigenous vegetation (and wetlands) per hectare per anum for water production.
Ian, your comments on parks are a bit harsh although I do share your concerns over the on ground management of these areas.
Warwick, re your question about my comment “.. during a drought of record proportions ..” This is based on the fact that inflows to Burrendong (on the catchment of the Macquarie) for the 68 months from December 2000 to July 2006 was approximately 1700 GL which is the same as the driest similar period on record that occurred from December 1934 to July 1940. The next driest period was December 1903 to July 1909 that received approximately 1950 GL. The first data set are actual observations whilst the latter two are modelled. Out of interest, for every 10 megalitres that is captured by the dam, 4 megalitres come into the system as down stream tributaries. It is also interesting that rainfall totals don’t necessarily tell the whole story when it comes to dams and like wise the marshes. The anticedent conditions, intensity and size of each event also plays a big part in what then is seen as runoff.
If you go to the BoM web page;
http://www.bom.gov.au/cgi-bin/climate/rainmaps.cgi
you can make drought maps for various periods, 36 month down to 3 month and it is obvious that the BoM data finds no drought at the Macquarie Marshes (MM’s) in the last 3 years. In the small timespan 3 months back to 6 months I think a drought area extends to Dubbo but no further.
It is possible to roll the 36 month period back further; can anyone find a BoM map showing drought at the MM’s ?
I have emailed two rainfall charts to Jennifer and I will be away till late Sunday.
These show you some rainfall history for the region from the BoM high quality rain dataset and you can see the obvious cycles in all charts. Trangie data is the closest HQ station to the MM’s and it shows that in the recent past conditions were similar to dry times times in the 1990’s and 1980’s, if you go back to the 1960’s rainfall was obviously less and even lower in the late 1930’s thru 40’s and earlier again WWI years into the 1920’s look the driest of all.
The other graphic, also of HQ data, from Mudgee and Bathurst, could be a fair proxy for long term trends higher in the catchment.
A significant point of interest here in all 3 charts is the HUGE rain increase ~1950 and later which coincides with cloud seeding experiments which ended in the 1970’s. It is worth pondering whether vegetation now under “severe ecological stress” as Malcolm Turnbull says, was maybe established in these decades of sometimes abnormally high rain.
It would be pointless wasting money trying to preserve features in the MM’s formed due to those high rainfall years which may never be repeated unless cloud seeding commences again.
Warwick – you need to develop yourself a runoff model. I’m sure with your knowledge you can – or adapt one. Chris Hogendyk makes the correct observation that rainfall doesn’t tell the whole story with respect to dams. As he says the antecedent conditions ( a very big effect) and the intensity and size of each event is very important. You need percentile runoff to do dams properly. Why doesn’t BoM have it. Maybe wron.net.au will make them. Notwithstanding looking at various length drought maps is interesting and fun.
The 1950s and 1970s were wet in areas other than those cloud seeded. You need to discount the activity of La Ninas and Interdecadal Pacific Oscillation before you’d invoke that hypothesis.
Does cloud seeding work when there are no clouds to seed? Incidentally I am surprised that Jen hasn’t run on cloud seeding. Would be that sort of maverick outside science that we could argue a conspiracy of politics has killed off – or simply for most of Australia (save the Tassie Hydro) it just doesn’t work – or work well enough. One notes Gingis’s efforts selling cloud seeding to Qld in the recent situation.
As for the thickening vegetation on the mountainous areas – I’m not sure – what has the fire regime been. Do we really know. Lack of fire history maps. How much buffering does it give you with shallow mountain soils anyway.
Luke and Michael, it is all about leaf area index. Dense regrowth forests have a greater leaf area than old growth which has greater leaf area than pasture. This means they use more water, faster. Which means that during any given interval between rainfall events, the soil moisture will be less in the regrowth forest than in old growth or pasture.
And this means a larger portion of each rainfall event is used in restoring the soil moisture profile with a smaller portion going to runoff or aquifer recharge.
The current head of CSIRO Water, Rob Vertessy, did much of the work in this area but there is good stuff by Zhang as well at the CRC for catchment hydrology.
This relationship works over a number climate types but below 500mm/year the distinction between an undisturbed open woodland and an open grassland is minimal and so, shows no variation in water yield.
The official position of DNRM is that they only recognise preliminary work done in 1986 which, conveniently for them, claims that the effect is only found in RF>900mm.
The observation of greater erosion in thick regrowth is related to the lack of understorey which increases the impact of flows. It is not an indicator of larger water flows although large flows can still take place.
The only point of caution is in assuming that two median rainfall years will have the same yield. They may have differing frequency and volume of events that change the yield. And it is also quite possible to have a 900mm rainfall event in a 700mm rainfall zone.
The other interesting aspect of broadscale regrowth events post fire and post harvest is that once the stand approaches full stocking capacity then the total leaf area can become indigestible to dependent species in a shorter time between rainfall events.
With Koalas (and Greater Gliders) the leaf is indigestible once the moisture content drops below about 65% and the nitrogen drops below 1.8% and this means that all those logged coupes of former state forest that are being handed over to Parks and Wildlife will provide superior habitat for a few years while the regrowth takes off and then suffer a drastic decline in their carrying capacity of all the leaf based food chain as they reach “lock-up”.
But don’t expect Aila Keto to be around to feed the little fuzzies. They’ll all die a slow, miserable and anonymous death like most victims of Bimbocology do.
Ian,
Aila Keto was awarded a great environmental prize last year in Sweden, it was about saving rainforests in Australia. Volvo sponsored this enviro prize…
Yes, Ann, disgusting isn’t it. The other irony is that the science has been conclusive for two decades that Koalas do not like closed forest, favouring open forest down to 30% canopy. They also favour disturbed sites over ‘old growth’ and are particularly fond of forest stands without any large old hollow trees.
But Aila stomped her foot and had her little whimsies met and we now have over 800,000 hectares of Koala habitat that is experiencing significant and unremedied canopy closure at a time when climate is already exacerbating the reduction in leaf moisture content and nitrogen levels.
And when they all start migrating in search of a decent feed, they will be weakened by malnutrition and disease which will then make them increasingly fall victim to dogs and roadkill. And Aila will blame it all on urban development.
Interesting perspective Ian…
Well, personally I’m glad that big companies such as Volvo can sponsor some environmental projects from their fat profits… guess of course this has a great PR- value for the company, saving animals such as the koalas and to mention that you want to save the rainforests.
Volvo is also involved in this sail around the world competition and sponsors money to the ” save the albatross” campaign.
Ann, it would also be interesting to know how many truck sales that award cost Volvo here.
Ian , is it really that bad ?… Jeez , all my retirement pension is invested in Volvo shares.
Ann, how did you manage to get shares in Volvo, when Ford own them?
You must have special “pull”.
Haha, Hasbeen…Who can keep track of all car companies today, Volvo is owned by Ford, Rolls Royce by BMW and so on, really it’s a shame…
As you have noticed I’m not business minded at all….