It is not at all generally the case that alluvial soil, after a few days' exposure to air, turns "as hard as concrete". That would be plinthite, probably, on Earth, which gets that way not from an alluvial origin but from high iron concentrations in steadily wet conditions.
Perhaps the planet in question has a lot of iron and arable alluvial soils are also indurable, but it's not something you could expect people to deduce from 'alluvial' and no other data.
That pedogenic detail aside, I have generally enjoyed this space-opera series. The main characters talk about how awful war is in a way that doesn't ring true to me for what adults would actually say, but I can take as a broad-brush painting of how the characters plausibly feel about morally iffy things they know they've decided to do. Possibly it's all aimed at the genre's twelve-year-old ideal reader. This would also explain the great care in knowing when the characters have on their special undies of various sorts; it's all very literal. And, come to think of it, sex is adumbrated, not twee but not laid out lasciviously.
And it mines history, mostly Napoleonic naval and US military, but anything where needed... I had forgotten that a filibuster was originally a opportunist invader from the States.
I was creeped out by Marque and Reprisal because its armed princess heroine decides that anyone who doesn't enjoy killing her enemies is weak. Maybe it's over-picky of me to question the tone of a character I find saner, especially when it makes this readable when actual history is too strong for my stomach. And there's plenty of it, at least six novels now.
Find in a Library: Kris Longknife: IntrepidSo wrote clew in SF&F. , Science.