Johnson, B. L., Richardson, W. B., and Naimo, T. J., 1995, Past, present, and future concepts in large river ecology: Bioscience, v. 45, no. 3, p. 134-141. Abstract How rivers function and how human activities influence river processes. Many important questions are likely to require natural experiments or large-scale manipulations that compare rivers or river reaches. Keywords rivers, watersheds, resource-management, ecology, water-resources-management, environmental-effects, river-basin-management, environmental-impact, ecosystems