global change; soil organic carbon; carbon sequestration; pyrogenic carbon; stable carbon and nitrogen isotopes
Schmidt MWI, Torn MS, Abiven S, Dittmar T, Guggenberger G, Janssens IA, Kleber M, Kogel-Knabner I, Lehmann J, Manning DAC, Nannipieri P, Rasse DP, Weiner S, Trumbore SE (2011), Persistence of soil organic matter as an ecosystem property, in NATURE
, 478(7367), 49-56.
Schmidt Michael W I, Torn Margaret S, Abiven Samuel, Dittmar Thorsten, Guggenberger Georg, Janssens Ivan A, Kleber Markus, Kögel-Knabner Ingrid, Lehmann Johannes, Manning David A C, Nannipieri Paolo, Rasse Daniel P, Weiner Steve, Trumbore Susan E (2011), Persistence of soil organic matter as an ecosystem property., in Nature
, 478(7367), 49-56.
Vasilyeva NA, Abiven S, Milanovskiy EY, Hilf M, Rizhkov OV, Schmidt MWI (2011), Pyrogenic carbon quantity and quality unchanged after 55 years of organic matter depletion in a Chernozem, in SOIL BIOLOGY & BIOCHEMISTRY
, 43(9), 1985-1988.
Abiven S, Hengartner P, Schneider MPW, Singh N, Schmidt MWI (2011), Pyrogenic carbon soluble fraction is larger and more aromatic in aged charcoal than in fresh charcoal, in SOIL BIOLOGY & BIOCHEMISTRY
, 43(7), 1615-1617.
Abiven S, Heim A, Schmidt MWI (2011), Lignin content and chemical characteristics in maize and wheat vary between plant organs and growth stages: consequences for assessing lignin dynamics in soil, in PLANT AND SOIL
, 343(1-2), 369-378.
Abiven S, Andreoli R (2011), Charcoal does not change the decomposition rate of mixed litters in a mineral cambisol: a controlled conditions study, in BIOLOGY AND FERTILITY OF SOILS
, 47(1), 111-114.
Abiven S, Menasseri S, Angers DA, Leterme P (2008), A model to predict soil aggregate stability dynamics following organic residue incorporation under field conditions, in SOIL SCIENCE SOCIETY OF AMERICA JOURNAL
, 72(1), 119-125.
Abiven S, Recous S (2007), Mineralisation of crop residues on the soil surface or incorporated in the soil under controlled conditions, in BIOLOGY AND FERTILITY OF SOILS
, 43(6), 849-852.
Abiven S, Menasseri S, Angers DA, Leterme P (2007), Dynamics of aggregate stability and biological binding agents during decomposition of organic materials, in EUROPEAN JOURNAL OF SOIL SCIENCE
, 58(1), 239-247.
Abiven S, Recous S, Reyes V, Oliver R (2005), Mineralisation of C and N from root, stem and leaf residues in soil and role of their biochemical quality, in BIOLOGY AND FERTILITY OF SOILS
, 42(2), 119-128.
Abiven S, Menasseri S, Leterme P (2003), Effects of added organic matter quality on soil properties: Dynamics of carbon and structural stability along the decomposition, in ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
, 225, 927-927.
Ruiz L, Abiven S, Durand P, Martin C, Vertes F, Beaujouan V (2002), Effect on nitrate concentration in stream water of agricultural practices in small catchments in Brittany : I. Annual nitrogen budgets, in HYDROLOGY AND EARTH SYSTEM SCIENCES
, 6(3), 497-505.
Ruiz L, Abiven S, Martin C, Durand P, Beaujouan V, Molenat J (2002), Effect on nitrate concentration in stream water of agricultural practices in small catchments in Brittany : II. Temporal variations and mixing processes, in HYDROLOGY AND EARTH SYSTEM SCIENCES
, 6(3), 507-513.
Understanding soil organic matter (SOM) dynamics is critical to meeting many environmental, agricultural, and forestry challenges relating to productivity and sustainability, including the potential of soils to sequester atmospheric CO2. The amount of C as stored as SOM represents two-thirds of the terrestrial C pool and is the primary energy source driving several critical biogeochemical processes. The mechanisms of C stabilization in soils remain poorly understood. A critical knowledge gap in soil organic C (SOC) cycling concerns the SOC portion known as pyrogenic C (PyC), which is a chemically heterogeneous class of highly reduced compounds produced by the incomplete combustion. In terrestrial ecosystems, C and N dynamics are closely linked due to the activity of organisms. During the last few decades, atmospheric nitrogen deposition in soils has increased as a result of climate changes and human activities. At present, however, it is not clear whether increased nitrogen deposition will accelerate or decelerate soil-organic-matter turnover. Also, because of these global changes, future summers in temperate regions will be warmer and drier than today, and wildfires will be more frequent, producing more fire-derived (pyrogenic) carbon (PyC), a relatively recalcitrant soil component. Quantitative information on the long-term fate of PyC in soil is still virtually absent. We propose to take advantage of existing expertise, unique sample materials, and infrastructure at an already established long-term temperate forest research site. We want to highlight the importance of the biological degradation processes of PyC in soil. Toward these ends:(1) We have 100 g highly labeled wood (13C: 800 ‰, 15N: 4.2 atom %) wood and 150 g PyC made (charred) from that wood. (2) Infrastructure and equipment for soil-CO2- and soil-water flux measurements have already been established by virtue of a previous experiment that also involved stable isotopes. (3) Laegern, a well-characterized forest research site, has been in existence for many years and hosts several ongoing research projects (including a CarboEurope flux tower). In this proposed long-term experiment, cylindrical mesocosms (10 × 25 cm) will be installed in the soil and filled with (1) 13C/15N labelled pyrolyzed wood, (2) 13C/15N labelled wood and (3) a no-litter control, either treated with nitrogen or not, resulting in a two-factor, two-treatment experiment. We propose a post-doc project to identify underlying processes of char and wood degradation under high and low nitrogen -by directly identifying micro-organisms decomposing PyC through the double label (13C, 15N), by describing microorganism community structures, by determining the alteration of the PyC chemical structure of the remaining char (CPMAS 13C and 15N NMR, molecular markers) in the dissolved fraction and in the bulk soil and by using the isotopes to trace the degradation products within the soil fractions and within the intact soil matrix using soil fractionation methods and NanoSIMS technology. This project will be novel and cutting-edge for several reasons: For the first time, the proposed project will (1) directly identify PyC decomposers, (2) directly quantify PyC degradation in vivo in a long-term field study, and (3) test the effect of nitrogen on decomposition of PyC and its wood precursor. The proposed project also takes up a number of urgent tasks, as described in the Intergovernmental Panel on Climate Change (IPCC) meeting on terrestrial carbon stocks (IPCC 2003): (1) quantifying changes in carbon stock; (2) employing high-technology measurements (e.g., isotope tracers and molecular markers) and (3) elucidating soil mechanisms in addition to measuring fluxes. The project will help to clarify our fundamental understanding of the fate of pyrogenic carbon in forest soil under present and future atmospheric nitrogen deposition, and will improve urgently needed field-based and global turnover models.