Press Release: Report examines biological responses to stream nutrients across the United States

February 15, 2022 Forest Management Industry News NCASI Updates

U.S. Forest Service Publication Spotlight
In partnership with NCASI

Report examines biological responses to stream nutrients across the United States 

Findings can help regulatory agencies protect quality of Nation’s water
Contact: Douglas Ryan, vog.adsu@nayr.salguod

In excessive amounts, nutrients like nitrogen and phosphorus can disrupt water chemistry and, ultimately, negatively affect water quality in forest streams. Nutrient pollution can degrade water for drinking, recreation, and wildlife and fish habitat. Efforts to control nutrient pollution by agencies that regulate water quality are often limited by scientific uncertainty about the complex interactions between aquatic biological communities and nutrients.

A new report published by the USDA Forest Service’s Pacific Northwest Research Station synthesizes studies of the biological responses to stream nutrients from 17 long-term research sites across the country. It contributes to the scientific base used by state and federal regulatory agencies to set and enforce water quality regulations.

The report reviews current science findings and datasets from 17 experimental forests and ranges with intensive, long-term stream studies. The forests are part of a network of long-term sites dedicated to research and managed by the Forest Service. The network includes watersheds that are largely undisturbed, which means they can provide baseline data on headwater stream conditions that can help inform the development of water quality criteria.

“This synthesis represents a first: it brings together in-depth findings from this national network of stream studies on experimental forests to make them readily available to the regulatory community,” said Douglas Ryan, a retired PNW Research Station ecologist and editor of the report. “This synthesis facilitates these agencies’ use of this rich body of science and identifies future investigations that could be done at these sites to inform regulatory science needs.”


  • The report synthesizes science findings from experimental forests in California, Colorado, Hawai’i, Idaho, Minnesota, Montana, New Hampshire, North Carolina, Oregon, Puerto Rico, South Carolina, Washington, West Virginia, and Wyoming.
  • The biological responses of streams to nutrients, including nitrogen and phosphorus, are synthesized for each of the 17 featured sites.
  • Each chapter is coauthored by experts from the regulatory community who evaluated how the existing science from each study can be used by regulatory agencies and identified future research that could be conducted to fill important regulatory knowledge gaps.
  • The report also synthesizes information about the effects of climate change, atmospheric deposition, and management activities on forest streams.

Read the Publication

Ryan, Douglas F., ed. 2021. Biological responses to stream nutrients: a synthesis of science from experimental forests and ranges. Gen. Tech. Rep. PNW-GTR-981. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 522 p.