stone stream in tres barras district santa maria rs brazil

zone wilderness wetlands watershed waterfall watercourse water vegetation underground turbulence tributary tres streambed stream stones stone spring sediment santa runoff rocky riverbed riverbank riparian riffle rapids pool pebbles nature natural moss meandering maria life landscape habitat gravel gorge geology freshwater flowing floodplain fish erosion environment eddy ecosystem ecohabitat district current creek channel cascade canyon brook brazil boulders biodiversity bedrock barras banks aquatic amphibians