California Nitrogen Assessment

The United States (California)

Geographical coverage

Geographical scale of the assessment Sub-national
Country or countries covered United States
Any other necessary information or explanation for identifying the location of the assessment, including site or region name

North America

Conceptual framework, methodology and scope

Assessment objectives

  • Gain a comprehensive view of N flows in the state, with emphasis on agriculture’s roles.

  • Provide useful insights for stakeholders into the balance between the benefits of agricultural nitrogen and the effects of surplus nitrogen in the environment.

  • Compare options, including practices and policies.

  • 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.

Mandate for the assessment

Funded by the David and Lucile Packard Foundation, due to concern about water quality and greenhouse gas emissions from agriculture, with interest from state government leaders.

Conceptual framework and/or methodology used for the assessment

Millennium Ecosystem Assessment (MA)

URL or copy of conceptual framework developed or adapted


System(s) assessed

  • Marine
  • Coastal
  • Inland water
  • Forest and woodland
  • Cultivated/Agricultural land
  • Grassland
  • Mountain
  • Urban

Species groups assessed

Ecosystem services/functions assessed


  • Food
  • Water
  • Genetic resources
  • Ornamental resources
  • Raw materials


  • Air quality
  • Climate regulation
  • Regulation of water quality
  • Waste treatment
  • Maintainence of soil fertility

Supporting Services/Functions

  • Nutrient cycling
  • Soil formation and fertility
  • Primary production

Cultural Services

  • Recreation and tourism
  • Spiritual experience

Scope of assessment includes

Drivers of change in systems and services


Impacts of change in services on human well-being


Options for responding/interventions to the trends observed


Explicit consideration of the role of biodiversity in the systems and services covered by the assessment


Timing of the assessment

Year assessment started


Year assessment finished


If ongoing, year assessment is anticipated to finish


Periodicity of assessment

One off

Assessment outputs


Communication materials (e.g. brochure, presentations, posters, audio-visual media)


Journal publications

Training materials

Other documents/outputs

Tools and processes

Tools and approaches used in the assessment

  • Modelling
  • Trade-off analysis
  • Scenarios

Process used for stakeholder engagement in the assessment process and which component

  • From 2009-2001, used multiple avenues -- stakeholder forums, farm visits, growers consultations, and industry field trips -- to engage with more than 350 stakeholders across 50 organizations.

  • Outreach events generated more than 100 nitrogen-related questions and provided data, practical examples, and management options to guide the assessment.

  • Collaboration with stakeholders to create four 'scenarios' on the future of nitrogen management in California agriculture.

  • A 30-member Stakeholder Advisory Committee provides feedback and acts as liaison between the CNA and members' constituencies.

Key stakeholder groups engaged

  • Farmer organizations and commodity groups

  • Environmental NGOs

  • Individual farmers, ranchers, nurseries

  • Fertilizer industry organizations

  • Government agencies

  • Health and social justice organizations

  • Research organizations

The number of people directly involved in the assessment process

Less than 10

Incorporation of scientific and other types of knowledge

  • Scientific information only
  • Resource experts (e.g. foresters etc)

Supporting documentation for specific approaches, methodology or criteria developed and/or used to integrate knowledge systems into the assessment

Assessment reports peer reviewed



Accessibility of data used in assessment

Policy impact

Impacts the assessment has had on policy and/or decision making, as evidenced through policy references and actions

Independent or other review on policy impact of the assessment


Lessons learnt for future assessments from these reviews

Capacity building

Capacity building needs identified during the assessment

Actions taken by the assessment to build capacity

Sharing of data/repatriation of data, Workshops, Formal training, Communication and awareness raising

How have gaps in capacity been communicated to the different stakeholders

Knowledge generation

Gaps in knowledge identified from the assessment

How gaps in knowledge have been communicated to the different stakeholders

Additional relevant information