Brief Summary of Minutes of Annual Meeting

2024 SERA 17 Agenda and Notes

8:00-8:05 am Call to order, Deanna Osmond Chair

Deanna thanked sponsors, executive team and Doug Smith/Martha Zwonziker/Steph Kulesza/Jazim Garcia-Lawson  for helping to set up this year’s meeting. Please take a look at the Sharpley issue of Journal of Environmental Quality that includes a history of SERA-17 (Macrae et al., 2024). Finally, SERA-17’s 5 year plan can be found on the SERA-17 website.

8:05-9:15 am

Session 1. Reflections on the critical source area concept and phosphorus across the globe.

R.W. McDowell, AgResearch NZ/Lincoln University

Rich reviewed the current state of knowledge and practices related to critical source areas and agricultural phosphorus.  CSA’s are intended to improve water quality. CSA’s should be cost-effectively, quick and easy (i.e., simple!). Rich reviewed the history of the development of CSAs and explained how academic perspectives of CSAs (emphasizing complexity) differ from those of policy-pakers. CSA mapping has taken different forms, from the P Index in the United States to distributed models to farm field assessment software.

• Critical source area management can be consistent with farm profitability (not just a drain on resources). New Zealand provides a great example of how critical source area management can provide significant economic gains in water quality and cost-savings compared with blanket adoption of best management practices. As a result, New Zealand’s Environmental Farm Plans (sic?), required of all farms in New Zealand, include CSA identification and management. New Zealand has also demonstrated that implementation of these plans results in watershed scale water quality benefits.
• Critical source areas are harder to find as scale of catchment increases. They are best applied to smaller catchments.
• Critical source areas are often very difficult to delineate, as thresholds are often subjectives. Examples of Sweden and Finland with widespread requirement of riparian buffers, at great economic cost, regardless of the status of a riparian area as a CSA. The P Index in the United States is an example where a tool developed to identify CSAs has been modified so much to local interests that it often seems to miss its role in identifying CSAs.

• Critical Source Area management works when there is good delineation of soil types and slopes. They are useful in typical years, but overwhelmed by extreme events. CSA’s work when land use is relatively stable. CSA’s work best at farm and field scale.
• Rich presented a global map of P contributions to periphyton to link P management with water quality outcomes. Make sure policy makers set reasonable goals, with appropriate reference conditions. It is also important to set realistic expections as to when, and to what extent, water quality benefits will accrue. Monitoring programs must be up to the task to be able to detect change (this requires resources).
• Critical source area management can be undermined by a variety of issues. For instance, lag times in watershed outcomes need to be understood (some times we can anticipate decades to observe benefits). So, then the issue is how to communicate complexity to policy makers and the public anxious to see change in shorter time frames?
• A lot of discussion around differences in the regulatory environment between the United States and New Zealand. All strategies should have adequate monitoring to understand the outcome. Voluntary adoption requires a premium on cost-effectiveness and ease of adoption if it is to be successful.

9:05-10:15 am

Session 2: Reflections on Legacy Phosphorus. How do we use phosphorus terminology: point – counterpoint of legacy P.
Andrew Margenot, University of Illinois. What’s in a name? The multidimensionality of “extra” P terminology?

Andrew introduced the proposal to distinguish between Legacy P and Residual P, based upon his paper in ES&T. In that paper: Legacy P is a mechanism of P transfer; Residual applies to the P left over from fertilizer application to soils. He then presented a review of the literature citing these terms. The first mention of residual P is in 1925. Legacy P is first mentioned in a Florida wetland paper in 1996. Andrew reviewed the distribution of Journals for different disciplines have published on legacy P. Often, legacy P is used interchangeably with residual.

Dimensions of legacy/residual P

• Mass balance approach (magnitude, how much?). Positive mass balance. Measured change in soil P. Change in P fractions vs. total?
• Form approach (what kind of P?). What is the P form of interest? What is the fate of that P?
• The origin approach. Based upon the entry of P (input ). For instance, anthropogenic vs. geogenic, indirect vs. direct
• The age approach. How long/how old?
• The impact approach.

Some dimensions are binary, but is this type of contrast the best approach? Binary versions exist for Age (old/new); form (labile/recalcitrant); origin (anthropogenic vs. geogenic).

Environmental P may be best described in three dimensional?

• Form/origin/age.

Amy Shober, University of Delaware. Towards a transdisciplinary and unifying definition of legacy phosphorus.

• Tie to Sharpley’s 2013.
• 3 year project to work toward concensus in a sub-group of SERA-17
• Legacy P has been used in an environmental context (water quality, environmental fate) – often a negative connotation
• More recently, Legacy P has been used to explain P sources and management in an agronomic context – this is usually a more positive connotation
• Literature approaches to legacy P
  • As a stock: (legacy P = total P- geogenic)
  • As a flux (legacy P = anthropogenic P – P used by crops)
• Unfortunately, we can’t measure legacy P directly. We can only measure total P.
• Recommendation: we need to consistently measure total P.
• Discussion: How does better defining legacy P improve things?
  • Helps people to be consistent
  • Explain lag times in watershed science.
  • Legacy P is important to understanding sources and apportioning responsibility.

Peter Kleinman, USDA-ARS. Legacy phosphorus project terminology survey update

• Introduced a SERA-17 initiative to bring in diverse perspectives on legacy P from multiple disciplines.
  • Summarize perspectives; Identify different schools of thought; Assess how perspectives tie to authors’ backgrounds. Advance an inclusive and useful definition?
  • Timeline
    • Author nomination submitted (who and why?) - Now-December 20, 2024
    • Review nominations, email authors - December 20, 2024 – January 10, 2025
    • One-pager due - April 1, 2025
    • SERA17/CEAP Workshop - June 24-26, 2025
    • Manuscript Submitted - September, 2025

10:45-11:15 am

Session 4: NRCS Update

Betsy Dierberger, USDA-NRCS, National Agronomist. NRCS Nutrient Management Conservation Practice Standard (590) Review

• 590 Standard is currently under internal review with NRCS. Identifying modifications that NRCS would like to make. There has already been an national review by subject matter experts identified by NRCS and draft revisions to the 590 Standard have already been developed. At this time, no details on revisions to the 590 standard are available.
• NRCS identified a set of questions that SERA-17 can address. SERA-17 will send feedback to NRCS.

11:30-12:00 pm

Session 5: Reports of Current Activities

• FRST including modeling portion of FRST, Nathan Slaton, University of Arkansas
  • FRST launched its public facing tool in April, 2024
  • FRST continues to work to grow its database.
  • FRST lime recommendation survey will be followed by a lime calibration study
  • FRST soil sampling depth research initiative
  • FRST will be adding S
  • Stakeholder survey through ALTA (commercial testing lab organization)
• Methods publication with organic P methodology, John Kovar, ARS
  • Updating the SERA-17 manual (Third Edition).
  • Deleting the manure analysis chapters (due to new manure analysis methods manual)
  • Combining chapters on similar topics.
  • Focus on methods used by SERA-17 members
  • Assemble an editorial board
  • Move to protocols.io?
  • New chapters on P determination protocols
  • Looking to recruit an editorial board (please submit your nominations)

• Meta-analysis of soil P drawdown, Luke Gatiboni, NC State University
  • 14 studies (56 drawdown sites)
  • Mehlich-1, Mehlich-3, Bray, Olsen tests
  • Normalized the soil tests to be expressed on an M3- basis
  • It is possible to draw down 50% of P in 8-12 years after cessation of fertilizations.

12:00-1:00 pm

Business Meeting

• Nathan McKinney (University or AR) retired as SERA-17’s Administrative Advisorr. Amy Grunden (NC State University) has taken over that role.
• Status of workgroups
  • BMP Workgroup, Osmond. Looking to add more fact sheets.
  • Climate Change, Nelson. This topic is being moved to inactive while we work on new topics.
  • New Work Groups, Likely to form several workgroups as part of the 2025 SERA17/CEAP Workshop on Legacy Phosphorus and Phosphorus in Drainage Waters in Fort Collins. These topics will be formed at the next meeting (2025).
• Discussion regarding Andrew Sharpley Early Career Award in Agricultural Phosphorus Sustainability. Please nominate candidates.
• Feedback on the meeting format. The 2024 meeting in San Antonio was well received and well attended and we will continue meetings associated with Tri-Societies without any food at the venues, thus lowering the costs.
• Discussion on incoming chair. Stephanie Kulesza was elected as the incoming chair (congratulations).
• Overview of the SERA-17 International Workshop on Legacy Phosphorus and Phosphorus in Drainage Waters in Fort Collins, CO, June 24-26, 2025, Kleinman. Website expected mid-December, 2024. Please register early .
  • Organizing committee: Pete Kleinman, Grace Miner, Joshua Mott, Kyle Mankin, Deanna Osmond, Kevin King, Zach Simpson, Doug Smith, Merrin Macrae, Troy Bauder
  • Discussions will be organized around processes, measurement, management and modeling for both Legacy P and P in Drainage Waters
  • Day 1 – plenary session to highlight ongoing issues in the two subject areas, followed by breakout sessions
  • Day 2- tour of Colorado South Platte River CEAP watershed and visit to brewery working with the perennial grain, Kernza
  • Day 3 – more breakout sessions followed by combined, concluding session and SERA17 business meeting

• Attendees: Andino (U Waterloo), Bolster (ARS), Bourns (KSU), Brazy (Eastern Research Group), Bruulsema (PltNutCanada) , Charkaborty (Auburn Univ), DePaw (U Waterloo), Dierberger (NRCS), Fiorellino (U MD), Fisher (Lake Erie), Flahive (EPA), Gatiboni (NCSU), Herges (Mosaic), Jarvie (U Waterloo), Jones (U IL), Ketterings (Cornell) Kleinman (ARS), Kovar (ARS), Kulesza (NCSU), LaBarge (OH State), Lyons (FFAR), Macrae (U Waterloo), Margenot (U IL), McDowell (New Zealand), Miner (ARS), Mott (ARS) Osmond (NCSU), Osterholz (ARS), Pease (U MN), Pokhrel, (U DE), Prasad (Auburn), Reiter (VT), Schneider (U Guelph), Scholz (ASU), Shober (U DE), Simpson (ARS), Simpson (MS State), Slaton (U AR), Smith (ARS), Torbert (ARS), Ward (U Conn), Wyss (Lake Erie), Zwonitzer (CA)