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Sandy Desert to Green Space

10/04/2017 11:09 PM

..."three types of “soilized” sand layers with thicknesses of 10–20 cm, which were obtained by mixing sand with a modified sodium carboxymethyl cellulose (CMC) solution (containing 2% modified CMC and 5% compound fertilizer) at a weight ratio of 1: 0.15, were placed on top of the plain sand layer in separate sections. Three types of commercially available sand for building and construction (clean river sand), with different fineness moduli of 1.22, 2.97, and 3.71 and without any soil content, were subjected to “soilization” for the experiment. In addition to these river sands, three other granular materials (machine-made sand from stone, sand mixed with machine-made sand from stone, and sand mixed with saw-dust) were also used in the planting experiment after “soilization.” Many types of plants (Fig. 1(a)), such as rice (Fig. 1(b)), corn (Fig. 1(c)), and sweet potatoes (Fig. 1(d)), were planted in the “soilized” sand. In each year of the experiment, the plants have survived the heavy rains and continuous high temperature over consecutive sunny days that are characteristic of the climate in Chongqing, China. During these periods of continuous high temperature, the plants have been appropriately watered at different intervals. The constraining material was added to the “soils” only once in the spring of 2013, and no further supplementation has been made to the “soils” after that, except for the addition of an appropriate amount of fertilizer each year since 2014. There have been two harvests each year, and the plants have always grown luxuriantly and fruitfully in the different “soils.” In the years 2014 and 2015, the comparison of the yields of the plants including corn, potatoes, sweet potatoes, radish, and oilseed rape was made with those grown in the nearby fields of natural soil. The results show that all yields in the experiment field were higher, and in particular, the yields of three plants (potatoes, sweet potatoes, and radish) with tuber or tuberous roots were 50% higher (with the reasons and underlying mechanism to be elaborated upon in our next paper on eco-mechanics of soil). The planting experiment proves that the “soilized” sand has not turned back into its original discrete state by the erosion of rainstorm. On the contrary, the plots that were watered more frequently (for example, the plot in which rice was planted) have been found to be heavily covered with algae (Fig. 1(e)). Our planting experiment further shows that the eco-mechanical attributes of the “soilized” sand have been further improved throughout the cycle of planting and cropping, with the “soilized” sand behaving increasingly similarly to natural soil. Three months after the first harvest, organisms such as ants, earthworms, centipedes, and insect larvae had already appeared in the “soil” (Fig. 1(f))."...

http://www.sciencedirect.com/science/article/pii/S2095809916311560

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Guru

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#1

Re: Sandy desert to green space

10/04/2017 11:16 PM

Interesting.

Leave it up to someone to patent it and charge too much.

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#2
In reply to #1

Re: Sandy desert to green space

10/04/2017 11:29 PM

Given how much of an impact this could have this is quite big news. All they need to do now is come up with a cheap and energy efficient method of removing salt from sea water and we have ourselves a readily available source of farmable land for the worlds population. Could Africa and Saudi Arabia become our world's new bread baskets?

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#3
In reply to #2

Re: Sandy desert to green space

10/05/2017 5:54 AM

More salt tolerant strains of crops would ease the desalting requirement....and as it was irrigated with fresh water over the years, salt levels could be driven down to the levels acdeptable for less salt tolerant crops.

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#7
In reply to #2

Re: Sandy desert to green space

10/05/2017 12:26 PM

Membrane Capacitive Deionization will be the winner:

  1. moderate to low capital cost
  2. extremely high water recovery ~90%
  3. the lowest net energy input per m3 recovered purified water ~ 1kWh/m3
  4. tunable output purity

The reason is it relies upon ion transport due to electric potential of 0.5-1.0 V, no high pressure needed, high current results in high throughput pure water.

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#4

Re: Sandy Desert to Green Space

10/05/2017 7:00 AM

Sounds like modified hydroponics to me, just with moisture retaining material added to the growing medium being the sand and other media described.

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#5

Re: Sandy Desert to Green Space

10/05/2017 8:57 AM

I'm baffled, I was recently informed there was a global shortage of sand.where on Earth did you find enough of this highly prized commodity??

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#8
In reply to #5

Re: Sandy Desert to Green Space

10/05/2017 12:26 PM

Apparently, your sand intelligence report was talking about just the sand in the box, not the part "outside the box".

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#6

Re: Sandy Desert to Green Space

10/05/2017 12:21 PM

One of the Texas Tech U. agricultural chemists used to live a couple doors down the block where my mom's house was here in Lubbock. Hal Dregne, was his name, if I correctly recall. He always stressed the high importance of soil gums (naturally made from decaying plant matter in the soil by bacterial action, as the primary factor in soil tilth, fertility, and retention of moisture. I guess this totally proves he was right.

Furthermore, the stuff used in absorbent diapers (a gel) was noted to have the same effect on sand about 20 years ago. Literally, it is possible to reclaim the Sahara Desert, the Gobi desert, the Mojave desert, and other.

The trick is to get enough low-cost water to these regions, along with the large infusions of money to jump-start agriculture in these areas. The remaining question lies in the length of time the soil gum or gel remains effective, and when it must be re-applied. These will be the areas of the world where the land mass increases for agricultural utilization.

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#9
In reply to #6

Re: Sandy Desert to Green Space

10/05/2017 1:13 PM

It has been demonstrated that once the soil is reclaimed no further treatment is needed , just fertilizer and water....

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#10
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Re: Sandy Desert to Green Space

10/05/2017 1:44 PM

...and proper agricultural and soil conservation practices, OK, good then.

This sort of thing should really make the global warming folks happy, since we know crop land is always cooler than sand desert. That much even I can understand, although I am not sure the whiz-bangs in the swamp will get it.

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#11
In reply to #10

Re: Sandy Desert to Green Space

10/05/2017 2:31 PM

Well actually the albedo levels tell the tale...

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#12
In reply to #11

Re: Sandy Desert to Green Space

10/05/2017 3:12 PM

I get that the albedo goes down, thus the area could will grow hotter? Actually I suppose that water transpiration serves as the great coolant. Maybe an even better solution would be to go to intensive agriculture under more or less white plastic ceiling greenhouses such as in Almeria region of Spain.

If that (albedo change) were the only case, then we would need to stop growing corn all over the United States, because that is the cause of HCCC (global warming), not the automobile, the truck and the jetliner.

Let the livestock (and the people) starve by golly, because we must save the planet....LOL

The problem with any form of knee-jerk legislation, it could involve busting your lip with your knee, and there are jerks involved. I hate when jerks get involved.

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#13
In reply to #12

Re: Sandy Desert to Green Space

10/05/2017 4:22 PM

Well the vegetation does consume CO2 thereby reducing this GHG....so I would characterize it as just a slower radiative process...

Earth's energy budget

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#14
In reply to #13

Re: Sandy Desert to Green Space

10/05/2017 4:33 PM

So the law of unexpected (unintended) consequences kicks in for all of the larger of mankind's activities...

Earth is a pretty smart old girl, I think she can balance us out in short order, if her father the son permits it.

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#15
In reply to #11

Re: Sandy Desert to Green Space

10/05/2017 4:47 PM

Abledo of sand can vary widely depending on sizes, shapes, and composition.

Some types of sand also act as fairly effective selective surfaces, such that early in the day, not as much heat is lost to reradiation, conduction, and convection, as is gained via the portion of incident light absorbed. The sand heat up above ambient until heat losses match heat gains.

One funny thing about this selective surface heating is that it is not well correlated with variations in color. There are white sands on some beaches on the Florida Gulf coast that get hot enough to blister bare feet by mid day, yet, sand which I wouldn't be able to visually distinguish on a different part of the beach barely rises above air temp. There are light colored concretes that have similarly wide disparities in the same effect.

I wonder how and how much thst type of thing effects the energy balance.

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#16
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Re: Sandy Desert to Green Space

10/05/2017 5:33 PM

Well surprisingly enough an albedo study was done on these revegetated fields....

Figure 1. Diurnal variations of the averaged albedo for sand dune in moving sand area and BSCs in revegetated area under clear skies. Each data point is an average of 6 measured data.

Figure 2. Diurnal variations of surface albedo and surface temperature of sand dune (a) and BSCs (b) on clear days.

https://www.researchgate.net/figure/254289684_fig1_Figure-1-Diurnal-variations-of-the-averaged-albedo-for-sand-dune-in-moving-sand-area-and

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#17
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Re: Sandy Desert to Green Space

10/06/2017 8:47 AM

Another truly amazing find great eagle!

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#18
In reply to #17

Re: Sandy Desert to Green Space

10/06/2017 12:26 PM

Can THC grow on dunes, buddy?

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#19
In reply to #18

Re: Sandy Desert to Green Space

10/06/2017 3:52 PM

I don't know, why don't you go try it, and then call the Filipino drug enforcement agency about it...

By THC, you meant "truly high corn", now didn't you.

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#23
In reply to #19

Re: Sandy Desert to Green Space

10/07/2017 3:36 AM

Exactly or perhaps absolutely not. Our congress pass a law making Marijane to be legal if used as a medicine, you know. What is troublesome here in our place is the "speed" or "ice" since ordinary and people under poverty line can somewhat afford and into it and consequently get this depression syndrome together with paranoia thingy, and somewhat get involved in robbery, rape and murder. Our authorities are cleaning the streets now. It's much safer today than last years or previous administration. Drug lords and pushers are running their assess everywhere and they themselves exterminate one another.

Ice is the worst drug of all times. So many here are hooked. Some already passed away.

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#20
In reply to #18

Re: Sandy Desert to Green Space

10/06/2017 5:35 PM

He's back...................

THC would explain a lot of your post's, Gutmonarch.

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#24
In reply to #20

Re: Sandy Desert to Green Space

10/07/2017 3:38 AM

I much better without it, JPool. I always a smily person even not drugged.

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#21
In reply to #16

Re: Sandy Desert to Green Space

10/06/2017 6:59 PM

I like the graphs. Interesting enough for a GA.

So, I suspect the variation in abledo is more dependent of light angle of incident with the effective plane of sand particles than it does with the sand temperature....light entering orthagonally (around noon) to the surface of a sand mass has a lower change of bouncing back out than light entering an effective plane of particles at a very small angle.

.

I suspect composition, particle size, shape and distribution of these properties also plays a significant role in abledo.

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#22
In reply to #21

Re: Sandy Desert to Green Space

10/07/2017 12:14 AM
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#26
In reply to #22

Re: Sandy Desert to Green Space

10/08/2017 2:37 PM

Really Anonymous user? The law of reflection is your first choice for modeling light interaction with a pile of sand?

Do you feel like you see your reflection in a pile of sand? You probably just have a lumpy amorphous body and face. A pile of sand doesn't return a representative not follow the law of reflection.

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#25
In reply to #21

Re: Sandy Desert to Green Space

10/07/2017 1:01 PM

Yes the temperatures seem to peak at the same level, but the sands tend to experience what I suspect is black body radiative cooling effect causing a much wider temperature swing, whereas the vegetated area having moisture seems to regulate the temperature making a much friendlier environment for the flora and fauna....

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#27

Re: Sandy Desert to Green Space

10/10/2017 12:39 PM

It will be interesting to see if this effort actually leads to pilot projects of (agriculturalising ?) places, like say, the Sahara Desert...

The article says the their Chinese desert has a readily available usable water reservoir of some 5.7 x 109 cubic meters. This is about 4.63 x 106 acre-ft...

Where, near the Nile River is there such a supply of (de-salted) water, to start from?...

Also, the imported sand appears very near to being a clean silt. Where is there also such a supply of comparable sand, also near the Nile?...

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#28
In reply to #27

Re: Sandy Desert to Green Space

10/10/2017 1:35 PM

In Egypt, most likely.

Who says there is no ground water beneath the Sahara Desert?

Saharan aquifer map

Mostly the pumpable locations and amounts are not consistent with traditional agricultural, although who says advanced agriculture (under whitish plastic roof would not work, and allow much increase food production in Africa.

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