Plant and Soil

, Volume 227, Issue 1, pp 215–221

On the assessment of root and soil respiration for soils of different textures: interactions with soil moisture contents and soil CO2 concentrations

  • Tjeerd J. Bouma
  • David R. Bryla

DOI: 10.1023/A:1026502414977

Cite this article as:
Bouma, T.J. & Bryla, D.R. Plant and Soil (2000) 227: 215. doi:10.1023/A:1026502414977


Estimates of root and soil respiration are becoming increasingly important in agricultural and ecological research, but there is little understanding how soil texture and water content may affect these estimates. We examined the effects of soil texture on (i) estimated rates of root and soil respiration and (ii) soil CO2 concentrations, during cycles of soil wetting and drying in the citrus rootstock, Volkamer lemon (Citrus volkameriana Tan. and Pasq.). Plants were grown in soil columns filled with three different soil mixtures varying in their sand, silt and clay content. Root and soil respiration rates, soil water content, plant water uptake and soil CO2 concentrations were measured and dynamic relationships among these variables were developed for each soil texture treatment. We found that although the different soil textures differed in their plant-soil water relations characteristics, plant growth was only slightly affected. Root and soil respiration rates were similar under most soil moisture conditions for soils varying widely in percentages of sand, silt and clay. Only following irrigation did CO2 efflux from the soil surface vary among soils. That is, efflux of CO2 from the soil surface was much more restricted after watering (therefore rendering any respiration measurements inaccurate) in finer textured soils than in sandy soils because of reduced porosity in the finer textured soils. Accordingly, CO2 reached and maintained the highest concentrations in finer textured soils (> 40 mmol CO2 mol−1). This study revealed that changes in soil moisture can affect interpretations of root and soil measurements based on CO2 efflux, particularly in fine textured soils. The implications of the present findings for field soil CO2 flux measurements are discussed.

citrusCitrus volkamerianaroot respirationsoil CO2 effluxsoil CO2 concentrationsoil water relationsVolkamer lemon

Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Tjeerd J. Bouma
    • 2
  • David R. Bryla
    • 3
    • 4
  1. 1.Department of HorticultureThe Pennsylvania State UniversityUniversity ParkUSA
  2. 2.Center for Estuarine and Coastal EcologyNetherlands Institute of EcologyYersekeThe Netherlands
  3. 3.Department of HorticultureThe Pennsylvania State UniversityUniversity ParkUSA
  4. 4.Water Management Research LaboratoryUSDA-ARSFresnoUSA