Question

Two, small, poorly drained lakes lie close to each other in a northern forest. The basins of both lakes are composed of the same geologic substratum. One lake is surrounded by a dense Sphagnum mat; the other is not. Compared to the pond with Sphagnum, the pond lacking the moss mat should have:

A) lower numbers of bacteria.
B) less-acidic water.
C) reduced oxygen content.
D) reduced rates of decomposition.

Answer 1

The correct answer is C)

Explanation: The lake with no Sphagnum mat has less disolved oxygen. The moss is a plant which generates and liberates oxygen as part of its metabolism. The oxygen disolves into the whater of the lake which has this Sphagnum mat, giving it a higher concentration of disolved oxygen than the other one.