I suppose that I really put two and two together when reading a (non aquatic) book on the rain forest, which mentioned that the Rio Negro in Brazil was dark, due to a weak tea effect as the water percolated first through the vegetation and then through the sandy subsoil (as opposed to clay subsoils elsewhere in the Amazon basin).
I suppose that I really group like things together when reading a (non aquatic) book on the rain forest, which mentioned that the Rio Negro in Brazil was dark, due to a weak tea effect as the water percolated first through the vegetation and then through the sandy subsoil (as opposed to clay subsoils elsewhere in the Amazon basin).