Pulse Brain · Growing Health Evidence Index
Tier 3 — Observational / field trialPeer-reviewed

Soil protein: A key indicator of soil health and nitrogen management

Katherine Naasko, Tvisha Martin, Christian Mammana, Jacob Murray, Meredith Mann, Christine D. Sprunger

Soil Science Society of America Journal · 2023

Read source ↗ All evidence

Summary

This field study investigates autoclaved-citrate extractable (ACE) protein as a newly established soil health indicator, comparing its dynamics against conventional nitrogen measures across eight management systems ranging from annual cropping to polyculture perennial systems over 33 years in Michigan. Polyculture perennial systems promoting soil health exhibited 2–4 times higher ACE protein concentrations than intensive annual or monoculture perennial systems, and ACE protein showed less seasonal fluctuation than other soil nitrogen pools, suggesting potential utility as a reliable indicator of soil health and sustainable management practice. The observed positive correlation between late-season ACE protein and yield across different systems indicates promise for the metric in predicting productivity, though further investigation of the mechanistic relationship between ACE protein and crop performance is warranted.

Regional applicability

The study was conducted in the United States (southwest Michigan) rather than the United Kingdom, though the temperate climate and mixed arable/perennial cropping systems share some similarity with UK farming conditions. Transferability to UK systems would require validation, particularly given potentially different soil types, growing seasons, and management practices; however, the findings on soil protein stability and its relationship to soil health indicators may be conceptually relevant to UK soil health monitoring frameworks and regenerative agriculture adoption.

Key measures

ACE protein concentration (g kg⁻¹), total soil nitrogen, ammonium-N (NH₄⁺-N), nitrate-N (NO₃⁻-N), crop yield, measured at four timepoints across a single growing season

Outcomes reported

The study compared autoclaved-citrate extractable (ACE) protein concentrations across eight contrasting management systems over a growing season, and assessed its relationship with other soil nitrogen measures and crop yield. ACE protein showed greater stability than other nitrogen pools and correlated positively with total soil nitrogen and ammonium, whilst negatively correlating with nitrate.

Theme
Farming systems, soils & land use
Subject
Soil health assessment & monitoring
Study type
Research
Study design
Field trial
Source type
Peer-reviewed study
Status
Published
Geography
United States
System type
Mixed farming
DOI
10.1002/saj2.20600
Catalogue ID
SNmomgxtr7-bt7p8d

Topic tags

Pulse AI · ask about this record

Dig deeper with Pulse AI.

Pulse AI has read the whole catalogue. Ask about this record, its theme, or how the findings apply to UK farming and policy — every answer cites the underlying studies.