Answer: you would then put more sand on top and wait then a little more water!
Explanation:
Because you have to sublimated the leaves
A meander forms when moving water in a stream erodes the outer banks and widens its valley, and the inner part of the river has less energy and deposits silt. A stream of any volume may assume a meandering course, alternately eroding sediments from the outside of a bend and depositing them on the inside.
Http://www.biocab.org/Carbon_Dioxide_CO2.html
<span>I believe you are looking for the term, Dichotomous Keying.</span>