TY - JOUR

T1 - Soil respiration across three contrasting ecosystem types: comparison of two portable IRGA systems

AU - Mills, Robert

AU - Glanville, Helen

AU - McGovern, Stephanie

AU - Emmett, Bridget

AU - Jones, Davey L.

PY - 2011/8/1

Y1 - 2011/8/1

N2 - An accurate assessment of soil respiration is critical for understanding and predicting ecosystem responses to anthropogenic perturbation such as climate change, pollution, and agriculture. Infra‐red gas analyzer (IRGA)–based field measurement is the most widely used technique for assessing soil‐respiration flux rates. In this study, respiration rates obtained with two common IRGA systems (LI‐COR 8100 and PP Systems EGM‐4) were compared across three ecosystem types. Our results showed that both methods were highly comparable in their flux estimates, but the associated methodology used (notably the use or absence of a soil collar) resulted in greater uncertainty in flux rates and a greater degree of intrasite variation. Specifically, the use of collars significantly decreased the flux estimate for both IRGAs compared to the no‐collar estimate. The disturbance caused by collar insertion was assumed to be a major factor in causing the differing flux estimates, with root and mycorrhizal severance likely being the main contributor. We conclude that the two IRGAs used in this study can be reliably compared for overall flux estimates but emphasis is needed to validate a common measurement methodology.

AB - An accurate assessment of soil respiration is critical for understanding and predicting ecosystem responses to anthropogenic perturbation such as climate change, pollution, and agriculture. Infra‐red gas analyzer (IRGA)–based field measurement is the most widely used technique for assessing soil‐respiration flux rates. In this study, respiration rates obtained with two common IRGA systems (LI‐COR 8100 and PP Systems EGM‐4) were compared across three ecosystem types. Our results showed that both methods were highly comparable in their flux estimates, but the associated methodology used (notably the use or absence of a soil collar) resulted in greater uncertainty in flux rates and a greater degree of intrasite variation. Specifically, the use of collars significantly decreased the flux estimate for both IRGAs compared to the no‐collar estimate. The disturbance caused by collar insertion was assumed to be a major factor in causing the differing flux estimates, with root and mycorrhizal severance likely being the main contributor. We conclude that the two IRGAs used in this study can be reliably compared for overall flux estimates but emphasis is needed to validate a common measurement methodology.

KW - carbon

KW - CO(2)

KW - flux chamber

KW - greenhouse-gas emission

KW - methodology

U2 - 10.1002/jpln.201000183

DO - 10.1002/jpln.201000183

M3 - Article

VL - 174

SP - 532

EP - 535

JO - Journal of Plant Nutrition and Soil Science

JF - Journal of Plant Nutrition and Soil Science

SN - 1436-8730

IS - 4

ER -