Microbial Respiration

AUS-AIF-LVG-SMR General Moderate confidence

Benchmark Value

15 mg/kg/day
Thresholds: Lower: —, Upper: 15
Direction: Higher is desirable ↑
Form: UpperThreshold

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context. The scoring engine uses 5 benchmarks together — the OptimalRange form drives the primary score, while 4 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary LowerThreshold Guard UpperThreshold Guard OptimalRange Guard Point Guard

Evidence & Context

A basal respiration rate of >15–20 mg CO₂-C/kg/day could be considered indicative of a potentially detrimental state.

Metric Definition:

Basal microbial respiration rate measured as mg CO2-C per kg of soil per day under standardized laboratory conditions.

Benchmark Definition:

Upper detrimental threshold of basal microbial respiration indicating system instability and carbon loss in arid inland floodplains and ephemeral river systems under livestock grazing and pasture.

Justification:

This threshold indicates a state where the system is 'hemorrhaging' carbon due to recent severe disturbance.

Sources (1)

Preview of Inherent Factors Affecting Soil Respiration - USDA, accessed July 30, 2025,
Inherent Factors Affecting Soil Respiration - USDA, accessed July 30, 2025, Journal

Twenty years of progress, challenges, and opportunities in measuring and understanding soil respiration, accessed August 13, 2025,

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Preview of Managing Grazing to Restore Soil Health, Ecosystem Function, and Ecosystem Services
Managing Grazing to Restore Soil Health, Ecosystem Function, and Ecosystem Services
Contextual Support GreyLiterature

Managing Grazing to Restore Soil Health, Ecosystem Function, and Ecosystem Services, accessed July 19, 2025,

View Source
Preview of Soil Respiration | South Dakota Soil Health Coalition, accessed July 30, 2025,
Soil Respiration | South Dakota Soil Health Coalition, accessed July 30, 2025,
Direct Evidence GreyLiterature

Aridity thresholds of soil microbial metabolic indices along a 3,200 ..., accessed July 19, 2025,

View Source
Preview of Soil Respiration in Relation to Ecosystem Types in an Arid Area, accessed July 19, 2025,
Soil Respiration in Relation to Ecosystem Types in an Arid Area, accessed July 19, 2025,
Contextual Support Journal

Soil Respiration in Different Agricultural and Natural Ecosystems in an Arid Region - PLOS

View Source

Context

  • Region Australia
  • Biome Arid Inland Floodplains & Ephemeral River Systems
  • Land Use Livestock Grazing & Pasture
  • Assessment Pristine Reference
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 18 Mar 2026

Notes

Values above this threshold suggest unsustainable consumption of soil organic matter and active degradation.

Related Benchmarks

Other benchmarks in the AUS-AIF-LVG-SMR family.

2 mg/kg/day Moderate
Livestock Grazing & Pasture · Pristine Reference
LowerThreshold Active v1
— mg/kg/day Moderate
Livestock Grazing & Pasture · Pristine Reference
OptimalRange Active v1