scenic background with filamentous algae. spirogyra.

afternoon algae background biology bottom brick brook brooklet colorful contamination control creek day dirty ecology environment fertilizers filamentous flow greenery greening greenyellow human influence mineral movement nature nobody old ooze orange painting pantone picturesque plant pollution problem rill rivulet runnel rustic scenic shallow silt slime sludge small smooth spirogyra stony stream streamlet summer theme vertical water