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Some thoughts - mainly about water and population

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  • bertrand789
    replied
    concernant l'usage de l'urine, ce sont les chinois qui ont de l'avance ...


    concernant l'?conomie de l'eau en agriculture ,



    il suffit de faire que les travaux valid?s de ce tr?s grand Monsieur soient la r?gle :


    http://open-library.cirad.fr/files/2...1162774426.pdf

    https://www.researchgate.net/publica...ale_permanente

    c'est un bonheur de visiter ceux qui font cela , mais ils sont bien trop rare ...

    Leave a comment:


  • JJackson
    replied
    I have not written anything in this thread for a while but I saw this today and I love it. Urine Bio-bricks.
    https://www.news.uct.ac.za/article/-...cks-from-urine

    Urine, sand and bacteria in and bricks & fertiliser out and all at room temperature. Traditional brick manufacture use vast amounts of energy in the firing and produces a lot of CO2. Whats not to like?

    As my earlier posts in this thread point out phosphates are running out (post #6) and India has an acute water shortage and are consequently not going to be able to achieve its goal of stopping 100s of millions of people defecating and urinating in the open by using flush toilets (#3).

    Unfortunately the article does not give enough detail to 'try-it-at-home' or I would. If you see anything with that info. please post.
    The linked paper at https://www.sciencedirect.com/scienc...1334371830188X only has an abstract - the rest is behind a pay firewall.

    Leave a comment:


  • JJackson
    replied
    In keeping with my use of this thread as a safe place to link to relevant data I offer this Nature Letters contribution on Global agricultural trade and the use of fossil water (GWD Groundwater Depletion).
    It is quite alarming and contains a wealth of data on GWD use by country to produce which crops and where they are then exported to. There are some absurd uses e.g. Kuwait using 22 tonnes of GWD to produce 1Kg of wheat.

    Groundwater depletion embedded in international food trade
    http://www.nature.com/nature/journal...ture21403.html

    Leave a comment:


  • Emily
    replied
    Re: Some thoughts - mainly about water and population

    http://www.reuters.com/video/2014/07...eoId=324261666
    Transcript
    Largest reservoir in U.S. drops to historic lows

    Thursday, Jul 17, 2014 - 01:26

    Lake Mead, the largest reservoir in the U.S., provides stark visual evidence of the western United States' ongoing drought, as the waterline drops to a historic low. Nathan Frandino reports.

    Atop the Hoover Dam in Nevada, more evidence of the west's ongoing drought. Iconic white "bath rings" mark Lake Mead's old water levels. Now the largest reservoir in the country has dropped to historic lows. (SOUNDBITE) (English) ROSE DAVIS, BUREAU OF RECLAMATION SPOKESPERSON, SAYING: "This is 15 years of historic drought. We're looking at possibly a normal year for 2015, but one normal year isn't going to catch us up. This year alone, the elevation dropped 20 feet and we had the lowest release into Lake Mead from Lake Powell that we've ever had in its history." The waterline now sits at the same level as when the lake was first filled in the 1930s. That puts Lake Mead at about 39 percent capacity - scary news for millions of yearly tourists who come to enjoy the dam and the lake. (SOUNDBITE) (English) MARK LILLIBRIDGE, TOURIST, SAYING: "I'm concerned, I'm concerned for the water, you know? Maybe it's forcing us as a society to watch our water use better and even in good years, hopefully we'll watch it in the future and safeguard something as treasured as water anyway." Still, Lake Mead continues to supply water to millions of customers. But officials warn that if the drought persists water shortages in the southwest are inevitable.

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  • AnnaLisa
    replied
    Re: Some thoughts - mainly about water and population

    I live in the Great Lakes. I just want to call attention to the new industry that is devastating several of our western Great Lakes states. Frac sand mining. They are doing mountain top removal of hundreds of large hills and bluffs in western Wisconsin right now. This is taking enormous amounts of water. The government in Wisconsin has been co-opted by large corporations and all of our environmental protections are now null. There is no limit on high capacity wells. When the sand is removed, so it the system that once purified our water. This is occurring at break neck speed as I write this. Additionally, they are beginning aerial spraying of manure via center point irrigation rigs. Yes, that's right. Spewing manure and industrial waste via irrigation rigs that fling this 500 feet airborne. Can you imagine what kind of microbes and poisons this will aerosolize that people will breathe? CAFOs are being invited in to 'reclaim' the land that the sand mines are devastating. There is no limit on the amount of manure they make or spread, by any method. It's terrible to be living thru this. I fear for my people. My nitrate level in my well is 22mg/l, that is twice what the cut off for safe drinking is. I require an RO. Our rural land is being turned into an industrial site. They are churning thru my state and leaving nothing but devastation in their wake. Ultimately, it's fueled by the gas and oil industry, with its mining and industrial farming complexes.

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  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    In the third post in this thread I wrote
    While the solutions to many of the problems are realistically achievable I am very pessimistic about their implementation, which brings us back to the politics. While disputes over oil have usually been amicably resolved the fields are static and if they extend across international boarders some kind of a solution based on how much resides in each territory can normally be reached. Water has historically been viewed as ‘free’, it flows and many catchments cover several countries. It is also a non negotiable input for humans and no government can survive if its people do not have water so can not produce food. Down stream countries are at the mercy of upstream countries should they decide to draw excessively, control flow by damming, or worse still, diverting rivers. Some of the treaties governing usage date back to colonial times and so were not negotiated by the states that are now disputing them. They also reflect population, usage and flow patterns which have little to do with the current situation and there is always one party who stands to loose with change and will not renegotiate.
    This article on the BBC site illustrates the point nicely. Open mic. gaffes are always illuminating.

    Egyptian politicians are embarrassed after being caught suggesting hostile acts against Ethiopia to stop it from building a dam across the Blue Nile.
    They were inadvertently heard on live TV proposing military action at a meeting called by President Mohammed Morsi.
    Full link at http://www.bbc.co.uk/news/world-africa-22771563.

    Leave a comment:


  • JJackson
    replied
    "Live as if you will die tomorrow - plant as if you will live forever."

    This is another BBC article with interviews with CEO's of Nestle and Cargil. They arguing along much the same lines as I am in this thread and many of the quotes are pointed and rather depressing but overall I find it hopeful in that if the heads of large organisations understand the problem and are going on the record, even evangelising, this is a step in the right direction.


    "We are now in a new world with a completely different level of food prices because of the direct link with fuel," he says.
    He says biofuels are only affordable because of the high subsidies they receive, particularly in the US.
    "It is absolutely unacceptable and cannot be justified," he says.
    "There is one demand that I have, and that is not to use food for fuel."
    [re the]Water crisis Mr Brabeck-Letmathe [Nestle chairman] says politicians have not understood that the food market and the oil market are the same - they are both calorific markets.
    "The only difference is that with the food market you need 2,500 calories per person per day, whereas in the energy market you need 50,000 calories per person," he says.
    The whole thing can be found here and is worth taking the time to read.
    Last edited by JJackson; May 29, 2015, 01:07 PM.

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  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    Towards the end of the post on African ground water (No.11 in this thread) I mentioned that much of the water that could be hand pumped from the shallower southern aquifer would be reasonably safe to drink. I also pointed out that the WHO had achieved its MDG improved water target.
    The linked BBC article gives more details but it seems the WHO announcement has caused some concern.

    The aim was to provide clean - as in safe to drink - water but this tricky to quantify without testing for heavy metals and pathogens, and no one seems to have agreed what clean means. What can be counted is who gets water from a tap rather than a river or pond even if it is the same water: this is 'improved' water.

    Now for the numbers. Lets start with the MDG (link to the MDG web site)
    • Target 7c: Reduce by half the proportion of people without sustainable access to safe drinking water and basic sanitation


    7.8 Proportion of population using an improved drinking water source
    7.9 Proportion of population using an improved sanitation facility
    There are about 7 Billion of us and the celebrations were because between 1990 and 2010 two billion more of them joined the 'improved' drinking water elite, leaving 800 million 'unimproved'. The problem is if you redo the estimate for 'clean' rather than 'improved' water only about half of us are in that club.
    A rather damning indictment of the 'haves' compassion for the 'have nots', what it means is each person in the club needs to sponsor one other person's membership application.

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  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    Al, the Libyan project (see link in earlier post) is drawing over 2 billion tonnes of water annually from the Nubian Aquifer. It is estimated to be about 150,000 billion tonnes in total but total volumes are misleading as they do not equate to extractable totals and the law of diminishing returns definitely applies to wells.
    The whole project is quite a technological achievement as the water is often over 500m down and costs to date are thought to be about $25Bn. The water is used for cities and general irrigation. Although Libya have put in the investment to tap the aquifer it extends into Egypt, Sudan and Chad so, as with surface water and oil wells, it has great potential for conflict unless agreements on drawing rights can be agreed.

    Edit
    This really ought to be with the first post in this thread but I only found it recently. It is a 3 minute animation covering the last 250 years called Welcome to the Anthropocene. It looks at population rise and resource consumption. http://vimeo.com/39048998

    Leave a comment:


  • Laidback Al
    replied
    Re: Some thoughts - mainly about water and population

    Originally posted by sharon sanders View Post
    Africa sitting on sea of groundwater reserves

    20 Apr 2012 13:53
    Source: Reuters // Reuters


    By Chris Wickham

    LONDON, April 20 (Reuters) - Huge reserves of underground water in some of the driest parts of Africa could provide a buffer against the effects of climate change for years to come, scientists said on Friday.

    http://www.trust.org/alertnet/news/a...ater-reserves/
    The lead paragraph of this media report borders on sensationalism. There is no such thing as "free" water. All of the earth's water resources are tied into the water or hydrologic cycle. The article (link) touts all of the water locked up in an aquifer under the Sahara implying it should be made available for pumping. In any aquifer, as long as water is extracted at the same or lesser rate than recharge, the pumping will be sustainable.

    But as JJackson notes the water under the Sahara is old or "fossil" water. The aquifer is probably not being recharged or only minimally so. And there is ample evidence that recent climate change is disturbing worldwide precipitation patterns associated with the water cycle so future recharging of this aquifer is uncertain as well. Any short term indiscriminate pumping of aquifer water in the Sahara will only exacerbate social problems in the region when the aquifer runs dry.

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  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    Another on topic report.
    This link is to the Royal Societies "People and the planet" Report download page which also has two interesting interviews with working group members. As a completely irrelevant side note I was delighted to see an old friend I had lost contact with on the Review panel. As the report is 134 pages I have not got much past the TOC but it is going to be controversial as it deals with family planning to curb population growth in the developing world, reduction in gross overconsumption in the developed world and global redistribution of wealth. AKA seriously messing with the status quo which never goes down well.
    If any one has read the report and feels like commenting please jump in. In the mean time this link is to the BBC's environment correspondent's take.

    Leave a comment:


  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    Sharon thanks for the link.
    I had seen the BBC article on the paper this morning and downloaded the report ,pdf (Quantitative maps of groundwater resources in Africa) with a view to reading it, which I have now done.


    Although it includes nothing new, in terms of fieldwork, it is still an important bit of research. They have not 'found' the water what they have done is collected all the available - extremely patchy - data on geology, local and regional aquifers, borehole yields etc. and try and make sense of it.
    I would like to be able to tell you what they found but to understand it you really need to spend a fair bit of time staring at the various maps included in the report. There is an awful lot of water but there are a number of overlapping parameters which need to be understood to grasp what it means.
    How deep do you have to drill to get to it and what is the sustainable flow from the borehole?
    Is the source archaic or is it being refreshed?
    How do the aquifers fit in with surface rainfall patterns?


    If we look at the first of these questions. The depth is important because it limits the type, and cost, of extraction equipment. A hand pump will only operate up to 50m and over a 100m much more expensive drilling and pumping equipment is required. Low flow rates make sinking anything more than a shallow bore and hand pump uneconomical. A hand pump needs about 0.2 l/sec, any kind of commercial irrigation and you want 5 l/sec plus, which the reports says is uncommon outside of the archaic aquifer ? which I will come back to. As an example the report says a standard centre pivot irrigator of the type used in the central plains of the US will require a borehole that can supply approximately 50 l/sec.

    The biggest reserves and those with the highest extraction rates are, broadly, under the Sahara and are typically 250m deep. This is the Archaic aquifer and dates back 5000 years to a time when the area was wet. Earlier posts in this thread have pointed out that it is selfish for current generations to use the planets reserves for their benefit alone. The reserve may be huge, and allow the greening of swaths of desert, but it is not inexhaustible and if used unsustainably it will result in an increased local population with no way to survive once the water runs out. This water is not being replenished so all use is basically unsustainable and needs to be carefully considered. The only really large project that I know of is Libya's Great Manmade River (Wikipedia link).

    Much of the rest of the continent has a much smaller water reserve and low potential abstraction rates. The good news is that it is generally nearer the surface and is being replenished. It is also still significant in quantity and, if used wisely, enough to smooth the worst effects of cyclical droughts lasting several years. It has the added benefit that most of it is safe to drink without further treatment.

    At the turn of the Millennium the worlds governments committed themselves to a set of development goals (MDG) to be achieved by 2015. Sadly we are unlikely to meet many of them but one we have already met is the improvement in clean water target, regretfully, the other half of the equation the improvement in waste water treatment which is one of the goals showing the least progress and no chance of being met. The fact that a lot of the water outside the archaic reservoir is most amenable to small scale hand pump extraction is probably a blessing in disguise as it renders it less likely to be squandered.

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  • sharon sanders
    replied
    Re: Some thoughts - mainly about water and population

    Africa sitting on sea of groundwater reserves

    20 Apr 2012 13:53
    Source: Reuters // Reuters


    By Chris Wickham

    LONDON, April 20 (Reuters) - Huge reserves of underground water in some of the driest parts of Africa could provide a buffer against the effects of climate change for years to come, scientists said on Friday.

    http://www.trust.org/alertnet/news/a...ater-reserves/

    Leave a comment:


  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    This is quite interesting. As always with climate related issues nothing is simple or clear cut. The 'margin of error'/'degree of uncertainty' on all our estimates and models is often larger than the predicted change - which dose not make for easy communication with the public, or policy makers.


    Charting unknown Himalayan waters
    By Navin Singh Khadka
    Environment reporter, BBC News

    The Himalayas hold the largest volume of ice outside the polar regions
    In the wake of a recent controversy over the retreat of Himalayan glaciers in which the UN's climate science body admitted that it was an error to assert that they would disappear by 2035, water availability has emerged as a key issue with even more uncertainty.

    Full article
    http://news.bbc.co.uk/2/hi/science/nature/8481856.stm
    Last edited by JJackson; May 29, 2015, 01:04 PM.

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  • JJackson
    replied
    Re: Some thoughts - mainly about water and population

    The Future of Food and Farming: Challenges and choices for global sustainability.
    Project aim: to explore the pressures on the global food system between now and 2050 and
    identify the decisions that policy makers need to take today, and in the years ahead, to ensure that
    a global population rising to nine billion or more can be fed sustainably and equitably
    .

    This a major new report commissioned by the UK government a couple of years ago and which has just been published. It is downloadable as a .pdf and runs to about 200 pages. It covers very much the same area as this thread and included in its 10 pages of references will be much of the same source material. I have not had time to read more than summaries and odd sections but it seems about right so far.

    If anyone has read the report and would like to post some highlights or thoughts please do so.

    I have been working, very slowly, on a new post for this thread but keep giving up as it is trying to make some suggestion of what a solution might look like. In its current draft it seems to require the dissolution of the Nation States and the replacement of Capitalism with an, as yet undefined, new economic system. While Marx may yet be right that Capitalism is only a transitory state following Feudalism I am not sure his preferred replacement, Communism, will suffice.

    If I ever get it postable I shall be back.

    Edit:
    My tip for reading these kind of reports is read the Exec. summary and Table of Contents and then go straight for the Annexes, they often hold the best bits. I recommend Annex E 'Project Reports and Papers' where you can find a link to download location for dozens of additional reports and case studies. Including one each for the five 'Challenges' within the report
    Challenge A: Balancing future demand and supply sustainably
    Challenge B: Addressing the threat of future volatility in the food system
    Challenge C: Ending hunger
    Challenge D: Meeting the challenges of a low emissions world
    Challenge E: Maintaining biodiversity and ecosystem services while feeding the world
    Last edited by JJackson; January 24, 2011, 09:20 PM. Reason: Added the text after Edit:

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