Anti desertification patterns

Note:
Original post title; "what dots in Niger?" has gone outdated meanwhile, for (the recently accepted) explanation check thread below! 

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Dotted surface earthworks next to Gamou, Niger:



Dotted surface next to Gamou Niger.kmz (847 B)

checking historical imagery we see, it has been developed between 2013 and 2015 since it is a permanent structure - 4 meters diameter "dots" in a way regular alignment.

any ideas what it is?

If you want others to ponder something unusual, the least you could do is post a placemark so we could look for ourselves. Given the straight line formed by the left edge of the dots, my first guess would be some sort of contamination of the GE image. Remember Roger of Occam!

hi washi! - thanks for response!

well, if it were only some imagery error, then it would be visible by one exact imagery date, but it is there on different imagery datasets. (e.g. check ZE imagery from 2016)
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(placemark attached, however a bit hard to spot since not highlighted with the purple strip of attachments as it were before.)

Maybe parts of an irrigation system (a kind of Qanats, or small fountains?) I also do not rule out pits  for plants (like here in the forum).

yeah, but it does not follows natural surface changes - it is way too regular, that were made by a very precise ruler.

I have tried to spot out changes in vegetation, but it seems the whole pattern only vanishing through the years... could it be about some seismic research or any such?

Feb 17, 2020 12:35:09 GMT syzygy said:

... could it be about some seismic research or any such?

Not in my opinion. The area is seismically calm and the location is too far from research facilities.
And what are the structures there? Do they belong together causally?

Those lines were already there before the dot-grid pattern and occupying a different swath of land:






Dot-grid pattern - Niger.kmz (2.45 KB)

These are perpendicular to the slight slope to NW, so probably were made to change water runoff,
also darkening of the dotted area could be sign of developed water supply of the soil, only it is another method tried out on the same plot. (?)
(notice overlapping, where combination of the two techniques could be tested)

Only a guess however...

maybe this is too simple of a guess, but given its close proximity to a city. is it possible that this is a waste dump? simply burying the trash in sand might be easier than digging holes. and the regular structure may be a result of disposing trash in an orderly manner. althoe I doubt that small citys in Niger care about such an expensive systematic system of processing waste.

do not think it is about waste - too regular and permanent shapes for dumping. (you can see public trash dumped around poorly developed settlement HERE)

that minimal amount of waste a small african settlement could produce is being burned I think and drifts away by the hot winds of the Sahara...

They maybe test bore holes, searching for water table

well, I am not that professional well-digger, but is not there too much of it, moreover by such density?

rather interesting however, that no shrubs were moved whilst the transition (check 2013-2015 imagery dates) - really as if only were some stamped-on imagery glitch..., but no, it is not:

just have find a small plot on 2013 imagery, where we see the process has already been started:

dots.outline.2013_Gamou.kmz (929 B)

There are two common reasons for squares such as this, one is tree/shrub planting, either for agriculture or de-desertifcation experiments. or  (if no vegetation is visible) simple de-desertification and dune stabilisation.

If you search the area to the ENE of M'hamid, Morocco you'll probably see some squares of rush-fences arranges in square grid pattern (M'hamid is south of the city of Zagora - it's the "end of the road" near the Morocco/Algerian border (only the tarmac/goudron - the roads/pistes continue)

The grids change shape as sand piles up over them so can change over time, but also look different depending on sun angles casting shade. Different regions use different styles and dimensions, some are experimental and less successful than others. 
They can also be used to catch windblown sand upwind (in the prevailing wind direction) of a settlement to prevent dunes forming and making iut uninhabitable


 Recent example  
These look relatively new, compared to the almost-buried ones I saw closeby in around 1998. I;ll see if I can find the older ones for comparison.  and will edit the post if I find them



Edit:

20 years old or more, with agriculture traces
 Im pretty sure the ones I saw 20+ years ago where these faded ones. They appear to have been used for agricultural planting (olive or posibly argan trees) due to the traces of irrigation pipes (the North-South lines joning the dots in between the squares. Note how they gradually fade and walls of one orientation to the sun appear inconspicuous due to the sun angle. The tree crop appears to have failed (some bad drought years siince 1998) and the very clear shaped of recent sand fencing just north of the old ones, closer to the road. (with interesting diagonal lines too)

Thanks for this most complete and reliable explanation tafrawti, so as for your very nice example from Morocco!

I also found a lot of anti desertification patterns around Niger and Chad, in central Sahara.

But because I'm on the hunt for ancient structures only, I didn't placemark many of them.

Attachments:

GEC-Staples.kmz (2.6 KB)