Measuring fine root turnover in forest ecosystems

• Published in: Plant and soil 2005-10, Vol.276 (1-2), p.1-8
• Main Authors: Majdi, H, Pregitzer, K, Moren, A.S, Nylund, J.E, Agren, G.I
• Format: Article
• Language: English
• Subjects: Carbon; Cores; fine roots; Forest ecosystems; Forest soils; forest trees; hyphae; literature reviews; Longevity; minirhizotron; minirhizotrons; Mortality; mycorrhizae; mycorrhizal fungi; Nutrients; Plant roots; Plants; Production estimates; radio carbon technique; Radiocarbon; root mortality; root production; root systems; root turnover; rooting; Roots; Roots of functions; soil core; soil cores; Soil ecology; Soils; Special Issue: Fine Root Workshop; statistical analysis; Statistical methods; Turnover time
• ISSN: 0032-079X; 1573-5036; 1573-5036
• DOI: 10.1007/s11104-005-3104-8

Development of direct and indirect methods for measuring root turnover and the status of knowledge on fine root turnover in forest ecosystems are discussed. While soil and ingrowth cores give estimates of standing root biomass and relative growth, respectively, minirhizotrons provide estimates of median root longevity (turnover time) i.e., the time by which 50% of the roots are dead. Advanced minirhizotron and carbon tracer studies combined with demographic statistical methods and new models hold the promise of improving our fundamental understanding of the factors controlling root turnover. Using minirhizotron data, fine root turnover (y-1) can be estimated in two ways: as the ratio of annual root length production to average live root length observed and as the inverse of median root longevity. Fine root production and mortality can be estimated by combining data from minirhizotrons and soil cores, provided that these data are based on roots of the same diameter class (e.g.,