Question

Why the northern part of the siberian plain is marshy?

Answer 1

Answer:

Many of the deposits on this plain result from ice dams that reversed the flow of the Ob and Yenisei rivers, redirecting them into the Caspian Sea, and perhaps the Aral Sea as well. It is very swampy and soils are mostly peaty Histosols and, in the treeless northern part, Histels.

Answer 2

Answer:

so sorry I can't understand what you are asking