caa a22 4500 606218963 CHVBK 20210128101115.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s11104-015-2423-7 doi (NATIONALLICENCE)springer-10.1007/s11104-015-2423-7 Changes in the chemical composition of soil organic matter over time in the presence and absence of living roots: a pyrolysis GC/MS study [Elektronische Daten] [Manuel Suárez-Abelenda, Riaz Ahmad, Marta Camps-Arbestain, Saman Herath] Aim: To determine changes in the organic matter chemical signature of soils incubated in the absence of fresh organic matter input, and how these were affected by the reestablishment of vegetation. Methods: An Alfisol and an Andisol were incubated in 1.50dm3 PVC pots for 295days. Thereafter two 0.65dm3 undisturbed subsamples from each pot were taken. In one subsample, Medicago sativa L. was seeded; in the other, the incubation was continued without plants for an additional period of 215days. Soils sampled at times 0, 295 d and 510day were characterised using pyrolysis-GC/MS. Results and Conclusions: During the first 295days (in which plants were absent) the most evident changes detected were the degradation of the most labile fraction as shown by the decrease of pyrolysis products of plant-derived polysaccharides, intact lignin and long-chain aliphatic compounds, along with the residual accumulation of guaiacol, mid- to short-chain aliphatic compounds, and the aromatic fraction. On day 510 and in the absence of plants, fingerprints of lignin and plant-derived polysaccharides largely decreased whilst microbial-derived polysaccharides showed an accumulating trend. Moreover the relative contribution of n-methyl ketones increased whereas that of long-chain aliphatic compounds, specifically n-alkanes, decreased. The relative contribution of plant-derived compounds was larger in the Alfisol at T0 and decreased more intensely than the Andisol along incubation. The Andisol had a considerable fraction of microbial-derived compounds (e.g., acetamide and diketopiperazine compounds). Plant inclusion (during the last 215days of incubation) increased (i) the presence of compounds associated with fresh plant detritus (e.g., plant-derived polysaccharides and lignin) and (ii) alkylated benzenes (likely root-derived). An enhanced microbial activity due to input of plant detritus could be inferred from the increased content of chitin-derived compounds, this being especially evident in the Andisol. Springer International Publishing Switzerland, 2015 Soil organic matter nationallicence Molecular characterization nationallicence Long-term laboratory incubation nationallicence Plant litter decomposition nationallicence Living roots nationallicence Py-GC/MS nationallicence Cellulose and lignin degradation nationallicence Andisol and Alfisol nationallicence Suárez-Abelenda Manuel New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut Ahmad Riaz New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut Camps-Arbestain Marta New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut Herath Saman New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut Plant and Soil Springer International Publishing 391/1-2(2015-06-01), 161-177 0032-079X 391:1-2<161 2015 391 11104 https://doi.org/10.1007/s11104-015-2423-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11104-015-2423-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Suárez-Abelenda Manuel New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut NATIONALLICENCE 700 1- Ahmad Riaz New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut NATIONALLICENCE 700 1- Camps-Arbestain Marta New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut NATIONALLICENCE 700 1- Herath Saman New Zealand Biochar Research Centre, Institute of Agriculture and Environment, Massey University, Private Bag 11222, 4442, Palmerston North, New Zealand aut NATIONALLICENCE 773 0- Plant and Soil Springer International Publishing 391/1-2(2015-06-01), 161-177 0032-079X 391:1-2<161 2015 391 11104