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Egypt has managed to plant trees in the desert using wastewater

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Re: Egypt has managed to plant trees in the desert using wastewater

#101

Post by dmos62 »

farseer wrote: post #99
dmos62 wrote: post #91

Earlier quoted context omitted.

Here's an interesting case study about a plantation in a dry ski resort. It has more info, which is otherwise a bit hard to find: https://www.youtube.com/watch?list=PL5MDcgMmY2CXV3x-v0KCjMd1... Notice, that it's a playlist with a bunch of these case studies. The device displayed in the video (the company makes a few different ones) didn't require watering at all, because it collects dew. It's also biodegradable, so t…

Dew collection at night and massive evaporation of the Sahara during daytime. Not sure if this would be enough to sustain a medium sized tree. Whatever works in Netherlands may not work in Egypt.

The collected water does not evaporate. The linked case studies are in extreme climates, like a 1500-1900 meter altitude mountainside or a desert in Spain, not central Europe.

Re: Egypt has managed to plant trees in the desert using wastewater

#102

Post by KaiserPro »

Kuinox wrote: post #32
mackatsol wrote: post #11

Sounds like they need a little Permaculture… https://www.permaculturenews.org/2009/12/11/greening-the-des... The video above is a followup (6 years later) to greening a section of the desert in 2003.

Permaculture don't work with modern tools, it works well in your garden, but require so much labor that you are economically doomed at scale.

Sorry, this is patently false.

Permaculture isn't about "going back in time" its about re-jigging things so that you are not having to put in a tonne of nutrients only to take them out again/let them be blown away.

For example in wide open pastures it can be as "simple" as planting trees for nuts/fruit/lumber widely spaced to cut down on wind. not only that but it cuts down on the need for water because.

This makes up for the reduction in sunlight getting to the grass.

aquaculture is about trade-offs. its about choosing overly high yield now, with ever increasing fertiliser/feed/water inputs (thus higher costs) or reduced yield in the setup phase for much more resilient/comparatively productive and cheaper yields in future.

Re: Egypt has managed to plant trees in the desert using wastewater

#103

Post by krageon »

panny wrote: post #93
danans wrote: post #2

It's not clear to me what the source of water is relative to the size of the forest, because IIUC, in dry regions like Egypt (and California, Israel, etc), unless you use drip-irrigation with targeted crops (which won't grow a forest), agriculture requires a huge amount of water compared to domestic water consumption, so the wastewater stream from the latter intuitively can't be nearly enough to support a forest. Per…

The point is to get rid of the wastewater safe/cheap/efficient rather than grow the forest. Water consumption isn't the concern. They certainly wouldn't be doing drip irrigation with wastewater because wastewater would clog the equipment. Evaporation is expected and desired. Treated human waste is full of pharmaceuticals and phosphates from detergents. It should not be used to grow food unless it is feed for animals.…

> It should not be used to grow food unless it is feed for animals

If the potential toxins on the crop are the concern, these animals can also then not be for human consumption (directly or indirectly). In a lot of cases they probably can't even produce things for human consumption. There's not a whole lot of use left once you eliminate those use cases.

Re: Egypt has managed to plant trees in the desert using wastewater

#105

Post by baq »

danans wrote: post #9
soperj wrote: post #4

Earlier quoted context omitted.

That's the current forest that was started in 98. The one that they're starting now is 100 million hectares (1 million sq km).

That is 380 times larger. Unless they are massively underutilizing the current wastewater stream, they need to multiply the irrigation water use efficiency that much, unless they think of forest is going to alter weather systems in such a way that brings rain to the area.

that's literally what rainforests do, after all.

Re: Egypt has managed to plant trees in the desert using wastewater

#106

Post by bumblebritches5 »

danans wrote: post #2

It's not clear to me what the source of water is relative to the size of the forest, because IIUC, in dry regions like Egypt (and California, Israel, etc), unless you use drip-irrigation with targeted crops (which won't grow a forest), agriculture requires a huge amount of water compared to domestic water consumption, so the wastewater stream from the latter intuitively can't be nearly enough to support a forest. Per…

.78 square miles isn't even large, that's a small park.

Re: Egypt has managed to plant trees in the desert using wastewater

#107

Post by baq »

Gustomaximus wrote: post #83
nicoffeine wrote: post #6

Earlier quoted context omitted.

Israel already gets the majority of its water, including for irrigation, from desalination.[1] They achieve this through a combination of conserving and recycling water as well as very targeted irrigation of crops, along with new technology such as the Sorek desal plant. The second generation may be up and running by 2023 [2]. There's an interesting paper [3] about building 40,000 Sorek style plants to sequester exce…

> One big technical problem is what to do with the brine Cant it be dumped back into the ocean at points where it can re-salinate?

you'll raise salinity at the dump point to toxic levels and mixing it with water by dumping via ship adds so much complexity and cost it isn't even worth writing about

Re: Egypt has managed to plant trees in the desert using wastewater

#108

Post by htnsao »

mettamage wrote: post #84
htnsao wrote: post #39

There's a better way to do it.. Trees can be planted in deserts without irrigation using technology developed by a Dutch company called Groasis [0]. They have also recently come up with a new version of their Waterboxx that can use any kind of wastewater to plant trees, even sea water. [1] Looks like it works via solar condensation which then wicks into the soil so the roots can follow it down to the deeper capillary…

I'm a layman in this area, but doesn't the Land Life Company (also a Dutch company) [1] use similar technology? [1] https://landlifecompany.com/technology/

A copycat started in 2013. Their Cocoon does not capture rainwater so is much less effective.

Groasis invented the concept in 2003. [0]

[0] https://www.groasis.com/en/products/the-development-of-the-p...

Re: Egypt has managed to plant trees in the desert using wastewater

#109

Post by htnsao »

jackmoore wrote: post #81
htnsao wrote: post #39

There's a better way to do it.. Trees can be planted in deserts without irrigation using technology developed by a Dutch company called Groasis [0]. They have also recently come up with a new version of their Waterboxx that can use any kind of wastewater to plant trees, even sea water. [1] Looks like it works via solar condensation which then wicks into the soil so the roots can follow it down to the deeper capillary…

You'd have to constantly refill it, which would still require irrigation for transport. Instead of centralized distillation plus transport, you have distributed mini distillers at point of consumption plus transport. This doesn't seem special, what am I missing?

There is moisture within ~3m in even the driest deserts. The water in the box slowly releases to make a connection with the capillary water deep below for the roots to reach within the first year. It's a planting method, not irrigation. Refills during rains, prevents evaporation via a clever siphon.
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