Description: Das Projekt "Root distribution and dynamics and their contribution to subsoil C-fluxes" wird vom Umweltbundesamt gefördert und von Universität Göttingen, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Abteilung Pflanzenökologie und Ökosystemforschung durchgeführt. It has been suggested that dying and decaying fine roots and root exudation represent important, if not the most important, sources of soil organic carbon (SOC) in forest soils. This may be especially true for deep-reaching roots in the subsoil, but precise data to prove this assumption are lacking. This subproject (1) examines the distribution and abundance of fine roots (greater than 2 mm diameter) and coarse roots (greater than 2 mm) in the subsoil to 240 cm depth of the three subsoil observatories in a mature European beech (Fagus sylvatica) stand, (2) quantifies the turnover of beech fine roots by direct observation (mini-rhizotron approach), (3) measures the decomposition of dead fine root mass in different soil depths, and (4) quantifies root exudation and the N-uptake potential with novel techniques under in situ conditions with the aim (i) to quantify the C flux to the SOC pool upon root death in the subsoil, (ii) to obtain a quantitative estimate of root exudation in the subsoil, and (iii) to assess the uptake activity of fine roots in the subsoil as compared to roots in the topsoil. Key methods applied are (a) the microscopic distinction between live and dead fine root mass, (b) the estimation of fine and coarse root age by the 14C bomb approach and annual ring counting in roots, (c) the direct observation of the formation and disappearance of fine roots in rhizotron tubes by sequential root imaging (CI-600 system, CID) and the calculation of root turnover, (d) the measurement of root litter decomposition using litter bags under field and controlled laboratory conditions, (e) the estimation of root N-uptake capacity by exposing intact fine roots to 15NH4+ and 15NO3- solutions, and (f) the measurement of root exudation by exposing intact fine root branches to trap solutions in cuvettes in the field and analysing for carbohydrates and amino acids by HPLC and Py-FIMS (cooperation with Prof. A. Fischer, University of Trier). The obtained data will be analysed for differences in root abundance and activity between subsoil (100-200 cm) and topsoil (0-20 cm) and will be related to soil chemical and soil biological data collected by the partner projects that may control root turnover and exudation in the subsoil. In a supplementary study, fine root biomass distribution and root turnover will also be studied at the four additional beech sites for examining root-borne C fluxes in the subsoil of beech forests under contrasting soil conditions of different geological substrates (Triassic limestone and sandstone, Quaternary sand and loess deposits).
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Göttingen ? Buche ? Trier ? Jahresring ? Biopharmazeutikum ? Aminosäure ? Pflanzenökologie ? Substrat ? Organischer Kohlenstoff ? Kohlenhydrat ? Skigebiet ? Verrottung ? Bodenkunde ? Lössboden ? Moorboden ? Siedlungsabfall ? Teich ? U-Bahn ? Waldboden ? Pflanzenwurzel ? Sand ? Sandstein ? Kalkstein ? Oberboden ? Unterboden ? Gelöster organischer Kohlenstoff ? Standortwahl ? Bildung ? Chemikalien ? Daten ? Studie ? Technik ? Säure ? Sediment ? Boden ? Verwitterung ? Ökosystemforschung ? Lebensalter ? Ackerland ? Bodenzustand ? Bodenqualität ? Messung ? Forschungseinrichtung ? in situ ? Zusammenarbeit ? Wald ? Maßnahme ? Berechnung ? Biomasse ? VERGLEICHEN ? BETRACHTUNG ? METHODE ? VERHAELTNIS ? ABSCHAETZUNG ? VERTEILUNG ? VERWANDT ? BEWERTEN ? NEU ? EINFANGEN ? WICHTIG ? POTENZIAL ? PROJEKT ? Alterung ? QUARTAER ERDZEITALTER ? UNTER ? ANGEWANDT ? KONTROLLE ? LEISTUNGSFAEHIGKEIT ? BEITRAG ? LOESUNG ?
Region: Lower Saxony
Bounding box: 9.16667° .. 9.16667° x 52.83333° .. 52.83333°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2013-01-01 - 2024-11-29
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