Though I must confess myself less interested by the siege at Léré than by the staggering drainage to its east.
Well, at least you've addressed my immediate first concern, which is that (amusingly) the map in the article doesn't include Léré. Via Wikipedia, it apparently got some military attention last year too.
1: That would be the Inland Niger Delta.
This is the usual "governments that depend on Russia for security are fucked" story, right? See Armenia and Syria.
Yeah, some googling about Wagner and Mali turns up this:
https://www.nytimes.com/2024/11/01/world/africa/russia-wagner-mercenaries-mali.html
3: Well yes teo I knew that! What I didn't know about was all the [tributaries? distributraries? anabranches?] perpendicular to the main channel. Drainage forced through folds? Flood advance and retreat through same? Phenomenal.
Yeah, so the delta seems to have two distinct parts. The southern portion is a more standard wetland. In the north the countervailing force are sands ridges running more east-west shaped primarily by the wind. So it is a a case where the aeolian and riverine factors are both significant, so the deltas channels are significantly controlled by the sand ridges.
Inland deltas develop where the gradient is suddenly reduced. Not sure what underlying geology causes it for the Niger; it might just be primarily determined by the continued influx of wind-driven sand.
Similar things here and here. How do you know it's sand not rock?
You put it in an egg timer and see if the eggs are overcooked before it flows through.
8: Mainly relying on sources. For instance: In the northern portion of the delta, channels fill in between sand dunes during the flood season.
https://eros.usgs.gov/earthshots/inland-delta-of-the-niger-river-mali
Was looking for some grund level pictures to confirm, but not really finding anything.