Rice varieties selected, elevations of silt rich bars where rice is sown, as well as planting and harvest dates are analyzed in the light of the timing, frequencies and amplitudes of observed stage reversals that have the potential to destroy growing rice.
The Mekong also provided water and silt to the sand bars and banks after the rainy season, and the farmers of Chiang Khong grew a rich harvest of soy beans, cabbage, lettuce, corn and other produce in these fertile seasonal gardens.
Bare (unlit and unfiltered) bubble bars raise silt, which will dissolve and decompose more rapidly, while moss filtering will remove ammonia and phosphate.
They spawn on silt-free gravel bars that would otherwise be exposed to air or covered by very shallow water were it not for the rises in the river from snow melt and annual spring rains that cause flooding.
The thick layers of sand are interpreted to be channel bars or channels, and the silt, clay silt, and silty clay are interpreted as overbank fines.
The select committee report concluded the bar would return through re-silting if it were dredged, and there were insufficient resources to prevent it.
It's not a big one, maybe 200 metres across, but in between I can see three stuck trucks, two fountaining silt dust into the air, the other motionless bar some frantic shovelling.
Grain size analysis indicated that slightly more silt and clay particles existed in sediments from inner point bars, compared to that from streambed and from locations near the point bar edges.
So we marched across the bar, walking alongside deep, Godzilla-sized bear tracks stomped into patches of silt, and dodging one very fresh pile of bear scat.
