Coping with variability: Examples of tracer use in root function studies

  • M. M. Caldwell
  • D. M. Eissenstat
Part of the NATO ASI Series book series (volume 15)


Spatial and temporal variability is an inevitable element in most field ecological studies. Belowground, this temporal variability and spatial patchiness is also to be expected, even though it may be less immediately apparent. Thus, assessment of root system phenomena such as production or nutrient uptake in the heterogeneous soil environment is a problem requiring intensive sampling combined with some manner of coping with the variability. Improved resolution from increased sample size often reaches a point of diminishing gains and unreasonable costs. Furthermore, practical constraints often limit the number of samples that can be taken. Use of tracers, such as radioactive isotopes, provides numerous advantages for nondestructively tracking some belowground processes. Because this can be done nondestructively, the same plants or plots can be followed through time which reduces the variability in the determinations. This chapter will portray two examples of the use of tracers in root system function research and discuss these in relation to alternative approaches.


Root Biomass Root Production Indicator Plant Radioactive Phosphate Agropyron Desertorum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Aber JD, Melillo JM, Nadelhoffer KJ, McClaugherty CA, Pastor J (1985) Fine root turnover in forest ecosystems in relation to quantity and form of nitrogen availability: a comparison of two methods. Oecologia (Berl) 66: 317–321CrossRefGoogle Scholar
  2. Caldwell MM, Camp LB (1974) Belowground productivity of two cool desert communities. Oecologia (Berl) 17: 123–130CrossRefGoogle Scholar
  3. Caldwell MM, White RS, Moore RT, Camp LB (1977) Carbon balance, productivity and water use of cold-winter desert shrub communities dominated by C3 and C4 species. Oecologia (Berl) 29: 275–300CrossRefGoogle Scholar
  4. Caldwell MM, Eissenstat DM, Richards JH, Allen MF (1985) Competition for phosphorus: Differential uptake from dual-isotope-labeled soil interspace between shrub and grass. Science 229: 384–386PubMedCrossRefGoogle Scholar
  5. Caldwell MM (1986) Competition between root systems in natural communities. In: Gregory PJ, Lake JV, Rose D (eds.) Root Development and Function: Effects of the Physical Environment. Cambridge Univ. Press, in pressGoogle Scholar
  6. Fabio A, Persson HA, Steen E (1985) Growth dynamics of superficial roots in Portuguese plantations of Eucalyptus globulus Labill, studied with a mesh bag technique. Plant and Soil 83: 233–242CrossRefGoogle Scholar
  7. Fitter AH (1982) Morphometric analysis of root systems: application of the technique and influence of soil fertility on root system development in two herbaceous species. Plant, Cell and Environment 5: 312–322Google Scholar
  8. Hackett C (1968) A study of the root system of barley. I. Effects of nutrition on two varieties. New Phytol 67: 287–299CrossRefGoogle Scholar
  9. Hansson A, Steen E (1984) Methods of calculating root production and nitrogen uptake in an annual crop. Swedish J Agric Res 14: 191–200Google Scholar
  10. Lauenroth WK, Whitman WC (1977) Dynamics of dry matter production in a mixed-grass prairie in western North Dakota. Oecologia 27: 339–351CrossRefGoogle Scholar
  11. Marshall JD, Waring RH (1985) Predicting fine root production and turnover by monitoring root starch and soil temperature. Can J For Res 15: 791–800CrossRefGoogle Scholar
  12. Milchunas DG, Lauenroth WK, Singh JS, Cole CV, Hunt HW (1985) Root turnover and production by 14C dilution: implications of carbon partitioning in plants. Plant and Soil 88: 353–365CrossRefGoogle Scholar
  13. Persson H (1979) Fine-root production, mortality and decomposition in forest ecosystems. Vegetatio 41: 101–109CrossRefGoogle Scholar
  14. Persson H (1980) Spatial distribution of fine-root growth, mortality and decomposition in a young Scots pine stand in Central Sweden. Oikos 34: 77–87CrossRefGoogle Scholar
  15. Robinson D, Rorison IH (1983) A comparison of the responses of Lolium perenne L., Holcus lanatus L. and Deschampsia flexuosa (L.) Trin. to a localized supply of nitrogen. New Phytol 94: 263–273CrossRefGoogle Scholar
  16. Runge M (1983) Physiology and ecology of nitrogen nutrition. In: Lange OL, Nobel PS, Osmond C, Ziegler H (eds) Encyclopedia of Plant Physiology, New Series, Vol 12C. Springer Verlag, Berlin-Heidelberg-New York, pp 163–200Google Scholar
  17. Shierlaw J, Alston AM (1984) Effect of soil compaction on root growth and uptake of phosphorus. Plant and Soil 77: 15–28CrossRefGoogle Scholar
  18. St John TV, Coleman DC, Reid CPP (1983) Growth and spatial distribution of nutrient-absorbing organs: selective exploitation of soil heterogeneity. Plant and Soil 71: 487–493CrossRefGoogle Scholar
  19. Singh JS, Lauenroth WK, Hunt HW, Swift DM (1984) Bias and random errors in estimators of net root production: A simulation approach. Ecology 65: 1760–1764CrossRefGoogle Scholar
  20. Snedecor GW, Cochran WG (1967) Statistical Methods. Iowa State Univ. Press, AmesGoogle Scholar
  21. Vogt KA, Grier CC, Gower ST, Sprugel DG, Vogt DJ (1986) Overestimation of net root production: a real or imaginary problem? Ecology 67: 577–579CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • M. M. Caldwell
    • 1
  • D. M. Eissenstat
    • 1
  1. 1.Department of Range Science and the Ecology CenterUtah State UniversityLoganUSA

Personalised recommendations