Assessment of Soil Biology and Plant Available Nitrogen for Soil Health and Water Quality

Project Overview

Project Type: Professional Development Program
Funds awarded in 2016: $49,690.00
Projected End Date: 09/30/2018
Grant Recipient: CAFES Center for Sustainability
Region: Western
State: California
Principal Investigator:
Hunter Francis
CAFES Center for Sustainability

Annual Reports


Not commodity specific


  • Animal Production: pasture fertility, range improvement
  • Crop Production: biological inoculants
  • Education and Training: demonstration, workshop
  • Natural Resources/Environment: soil stabilization, carbon sequestration
  • Production Systems: agroecosystems, organic agriculture
  • Soil Management: composting, soil analysis, nutrient mineralization, soil chemistry, soil microbiology, organic matter, soil physics, soil quality/health

    Proposal abstract:

    Summary: Soil biota and organic matter are being increasingly recognized as a fundamental component of soil health. While this fact has long been known to soil scientists and segments of the professional community in agriculture,1 recognition is becoming widespread for several reasons: 1) depletion of soil organic matter is resulting in erosion and loss of soil fertility, 2) the ability of soil organic matter to increase soil water holding capacity is gaining attention as the West struggles with prolonged drought, 3) the ability of biologically-rich soils to cycle and retain otherwise leachable nutrients is being linked to the maintenance of water quality, and 4) the capacity for soil biology to play a significant role in the sequestration of atmospheric carbon is attracting considerable attention as leaders look for ways to mitigate and adapt to climate change. Better understanding and validation of all of these important aspects of soil health is needed overall, and better understanding of the relationship between soil organic matter and mineralizable nitrogen is particularly needed in the assessment of a soil’s potentially positive contribution to plant nutrition and potentially negative effect on water quality (through leaching). The goal of this project is to engage a wide cross-section of stakeholders to develop web-based training and resources along with hands-on field workshops for professionals on soil health, with a specific focus on new, practical and affordable methods to assess soil biological activity overall and mineralized plant available nitrogen in particular.

    Project objectives from proposal:

    1) Provide training to agriculture professionals such as Cooperative Extension, NRCS and RCD specialists, soil
    consultants, certified crop advisors, land managers, compost and other industry professionals featuring cutting-edge information on the assessment of soil biology and plant available nitrogen 2) Equip professionals with data-driven solutions for pressing soil and water challenges, namely the ability to monitor soil organic matter and nutrients to inform better management of soil and water systems 3) Expand the “toolbox” of relevant professionals by providing them with information and hands-on training on innovative, contemporary techniques for assessing soil biology and nutrients, such soil respiration (e.g., microbial activity, microbial biomass, and “carbon burst” methods) and chemical residue analytic techniques (e.g., enzymatic nitrate tests) 4) Provide a comprehensive overview of how soil biology and organic matter relate to soil health, as well as to other physio-chemical parameters 5) Put a special focus on how carbon and nitrogen cycle in soils, and how soil organic matter content relates to the mineralization of plant available nitrogen 6) Promote understanding of the role and value of organic nitrogen and its relation to inorganic nitrogen 7) Provide basic training on how to create/manage nutrient budgets and promote methods for increasing soil organic matter and building beneficial soil biology 8) Discuss the relevance of educational materials developed to other pertinent fields, such as composting (and the effect of compost additions on soil biology and health), water quality monitoring and management, carbon sequestration in soils and advanced laboratory techniques for assessing soil microbial ecology (e.g., metagenomics) 9) Leverage Cal Poly State University’s vast network of alumni and industry supporters to disseminate grant deliverables 10) Specifically, develop five primary outcomes: a) host an inaugural “Soil Health” presentation/event at Cal Poly featuring a leading expert on soil biology and its assessment to raise campus, community, industry and overall stakeholder awareness of the project and its significance, b) a six-part “screen-cast” video series delineated below to be offered via our Center’s website that will be offered free to the public, c) a certificate of completion for those wishing to receive proof they completed the web-based training, d) three follow-up field day workshops in southern, northern and central California that will demonstrate principles and assessment methods featured in the web-based videos, and e) compilation of resources pertinent to the project that will also be made available on the Center’s website. Timetable: Fall 2016: Convene stakeholders; assemble materials; develop the six web modules Winter 2017: Hold soil health event at Cal Poly; complete and launch web screen-cast presentations and certificate series; conduct southern CA field day Spring 2017: Conduct northern and central CA field days; compile project resources; write final report

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.