The health of streams in agriculturally dominated watersheds has long been assumed to be almost entirely dependent on nearby agricultural practices. In that regard, governments are making substantial investments in the modification of agricultural production activities. Conservation practices have reduced nutrient, sediment, and contaminant loads to those streams, but evidence remains strong that water quality and stream health, especially of those streams draining into the Mississippi River, are still a challenge.

As Project Manager Rick Cruse states, "The Iowa Water Center is partnering with CAST to address the relationship between land management and stream water quality and, in particular, factors that seem to negate or minimize the impacts of farm management practice changes on stream water quality improvements."

Understanding the role and interplay of land- and stream-related factors in determining water quality is necessary in implementing watershed changes and allowing time for these changes to translate to stream improvements. The publication includes sections on the following:

  • Stream ecology primer
  • Time lags between land management changes and water quality impacts
  • Watershed hydrology and material transport to streams
  • Buffering capacity of streams
  • Land resource characteristics impacting stream response to land management changes
  • Restoration of stream health

The authors are highly respected experts, and they consider that a whole systems approach, one that takes into account the many factors responsible for water and stream degradation, may be necessary to repair the quality of the nation's streams and rivers. A more integrated watershed management approach and a systematic understanding of the role land and stream elements play in stream water quality and function are critical to (1) identifying the causes of water degradation, and (2) devising a strategy to improve water conditions in the nation's streams in agriculturally dominated watersheds.

CAST is an international consortium of scientific and professional societies, companies, and nonprofit organizations. It assembles, interprets, and communicates credible, science-based information regionally, nationally, and internationally to legislators, regulators, policymakers, the media, the private sector, and the public.

Order Information for Special Publication 31
Hard Copy: $18 U.S. plus shipping and handling.  
8½  x 11 * soft cover * 48 pp.       
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