The Biology of a Submerged Marigold
When a marigold garland sinks into a pond, bacteria begin breaking down the organic matter almost immediately. The decomposition of plant cellulose and pigment compounds is aerobic, it consumes dissolved oxygen. A single large garland introduces enough organic load to measurably depress oxygen levels in a small, shallow water body within 48 hours. Banana stems, which are dense with moisture and starch, decompose more slowly but release a larger total carbon load over days. Leaf cups and coconut husks follow the same curve. The problem is not any one offering. It is the volume arriving in a compressed window of time.
