Sediment Compaction and Muck Reduction

Lake bottoms are characterized by particulate matter transported into the lake from the watershed (i.e., allochthonous sources), organic matter produced within the lake (i.e., autochthonous sources), and the biochemical processes that modify both components. Decomposing aquatic plants – both submersed, rooted plants as well as algae – represent the primary autochthonous contribution of organic matter to lake sediments. The demand for dissolved oxygen for decomposition is sufficiently great to create anoxic conditions in the sediments. Anoxic sediments are characterized by brown/black muck with a noxious odour that smells like rotten eggs due to hydrogen sulfide (H2S) accumulation. Anoxic conditions reduce the rate of organic decomposition, allowing organic matter to accumulate on the lake bottom. This organic matter, together with settled clays, creates a mucky bottom sufficiently flocculent that a person may sink up to their ankles when standing in shallow waters.

SolarBee’s long-distance circulation impacts lake sediments by maintaining a slow but steady flow of oxygen-rich water across the sediments from the water’s edge down to the depth of the unit’s intake hose. Surface waters enriched with dissolved oxygen via surface reaeration and algal photosynthesis are pulled from shorelines back to the SolarBee with the return flow. The oxidation of these sediments facilitates organic decomposition and sediment compaction. Lake owners frequently report that near-shore sediments are now firm enough to walk on without sinking. This oxidation of lake sediments has other benefits as well, including an improved fishery from greater spawning success, reduced filamentous algae growth, and invasive aquatic weed reductions from reduced ammonia-nitrogen availability in the sediments.


Noxious odours

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