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The California Nitrogen Assessment is currently in Stakeholder Review. Please see the Stakeholder Review page for access to the draft report and information about participating as a stakeholder reviewer.

Nitrogen plays a critical role in the global food supply, but the tradeoffs of excess nitrogen application involve increased costs for farmers and consequences for the environment and human health. Despite increasing awareness of the importance of these tradeoffs, there is still a lack of cohesive knowledge that gives a big-picture view of  California’s nitrogen system. The California Nitrogen Assessment (CNA) is designed to fill this void.

The California Nitrogen Assessment is an ongoing research initiative of UC SAREP and ASI.  The CNA has undergone a rigorous scientific review process and has entered the stakeholder review stage. During the stakeholder review period of each section of the CNA report, interested stakeholders from the general public are invited to review and comment.

If you are interested in being notified when upcoming sections of the CNA are available for review, please contact Mariah Coley at the Agricultural Sustainability Institute.

Download the CNA project summary here.

See our list of review editors for the CNA.

Download the CNA's table of contents for a look at what's to come. 

Learn more about Nitrogen

Subscribe to the ASI Blog Nitrogen in the News
Groundwater issue stirs up California agriculture

June 29, 2012 - Western Farm Press A recent Tulare meeting on groundwater nitrate brought farmers and agriculture professionals out to share resources and information on how the agricultural community can work to combat nitrate contamination.

Sonja Brodt to speak at upcoming Groundwater Resources Association meeting

Sonja Brodt will discuss initial findings of the California Nitrogen Assessment, focusing on the Mass Balance of nitrogen in California, at the upcoming Groundwater Resources Association meeting. The meeting theme is Salt and Nitrate in Groundwater systems: finding solutions for a widespread problem. June 13-14 Radisson Hotel and Convention Center Fresno, CA

Fertilizer use responsible for increase in nitrous oxide in atmosphere

April 2, 2012 - UC Berkeley News Center

Subscribe to the ASI Blog UC Davis research on Nitrogen
On-farm research projects in California

The Plant Sciences Agroecology Lab at UC Davis runs many on-farm research projects, some of which study the effect farming practices have on nitrogen emissions. Their website offers a lot projects to explore.

Nitrogen Faculty Workgroup

A portion of funding from the David and Lucile Packard Foundation helped to fund UC Davis faculty researchers who are studying nitrogen in a variety of forms. Read about their research efforts here.

Addressing Nitrate in California's Drinking Water

Released March 13, 2012 - UC Davis Report for the Stat Water Resources Control Board SBX2 1 Report to the Legislature. The condensed version of the report and longer technical reports can be downloaded here.

Subscribe to the ASI Blog Nitrogen Network
International Nitrogen Initiative

Optimizing Nitrogen use in food and energy production & minimizing the consequent harm to humans and the environment.

Nitrogen Management Project Protocol

The Climate Action Reserve (Reserve) has developed an agriculture sector Nitrogen Management Project Protocol (NMPP) to provide guidance on how to quantify, monitor, and verify greenhouse gas emission reductions from improving nitrogen use efficiency in crop production. The protocol is now available for public review and comment and it is to be considered by the Reserve Board in June 2012.

Reactive nitrogen in the US: An analysis of inputs, flows, consequences and management options

US EPA science advisory board report


Background on the Assessment

Our approach: The CNA comprehensively examines the existing knowledge on nitrogen science, policy, and practice in California. Our scientists have collected and synthesized a large body of data to analyze patterns and trends. This approach aims to move beyond "academic business as usual" to more effectively link science with action and to produce information that informs both policy and field-level practice.

What is unique about the CNA: Rather than generating new primary data, the CNA looks at existing knowledge to distinguish between what is well-known about agricultural nitrogen, and that which is more speculative. A large amount of information already exists on agricultural-related nitrogen in California that has never been looked at as a whole. The CNA adds value by sorting, summarizing, synthesizing, analyzing, translating, and communicating this information.     

The CNA includes:

  • Identification of underlying drivers (e.g., regulations, population growth) and direct drivers (e.g., fertilizer use and soil management, fuel combustion) that affect stocks and flows of nitrogen in California agriculture.
  • Calculation of a mass balance to examine how nitrogen moves through California agroecosystems and the state as a whole (including agriculture, sewage, industry and transportation).
  • Evaluation of the state of knowledge about nitrogen's impacts on ecosystem health and human well being. 
  • A series of scenarios, or "plausible stories about the future," that provide insights about nitrogen issues that will require attention over the next 20 years.
  • A suite of practices and policy options and the potential effects each would have on agriculture, the environment, and human health.
  • Outreach Materials that help the public understand the complex nature of the nitrogen cycles and help decision makers at the farm and public policy levels.                                                                                                    

Stakeholder involvement: A primary goal of the assessment is to develop information and products that are relevant to stakeholders. Because of this, stakeholder participation will play a key part in disseminating the results, and has already helped to shape the direction of the assessment.  The assessment process included stakeholder meetings to generate research questions and to develop a series of "scenarios" of the future of nitrogen in California.  We have conducted outreach to producers and industry groups, policy makers, non-profit organizations, and government agencies to involve them in these activities.  A distinguished eight-member technical advisory committee provides oversight for the project, a stakeholder advisory committee provides comment and review from stakeholders' perspectives, and an eight-member multidisciplinary faculty work group on nitrogen science and agriculture conducts complementary research.  

Our team: Our project is led by four principal investigators – Thomas P. Tomich, Dan Sumner, Kate M. Scow, and Randy Dahlgren – professors at the University of California, Davis. Additional project staff includes three post-doctoral research fellows, two communications and outreach fellows, and academic and communications coordinators. A distinguished nine-member technical advisory committee provides oversight for the project, a stakeholder advisory board provides comment and review from stakeholder perspectives, and an eight-member multidisciplinary faculty workgroup on nitrogen science and agriculture conducts complementary research.

Background: The California Nitrogen Assessment is funded by a grant from the David and Lucile Packard Foundation. Work on the assessment began in January 2009, and will continue through 2013.

Our Partners: The Agricultural Sustainability Institute at UC Davis is partnering with the following organizations to conduct the California Nitrogen Assessment: