tailieunhanh - Báo cáo lâm nghiệp: "Soil carbon dioxide efflux in pure and mixed stands of oak and beech"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Soil carbon dioxide efflux in pure and mixed stands of oak and beech. | Ann. For. Sci. 64 2007 141-150 INRA EDP Sciences 2007 DOI forest 2006098 141 Original article Soil carbon dioxide efflux in pure and mixed stands of oak and beech Mathieu JONARD Frédéric André Francois JONARD Nicolas MOUTON Pierre PROCÈs Quentin PONÈTTÈ Université catholique de Louvain Faculté d Ingénierie Biologique Agronomique et Environnementale Unité des Eaux et Forets Croix du sud 2 009 1348 Louvain-la-Neuve Belgique Received 5 May 2006 accepted 7 June 2006 Abstract - Total Soil Respiration TSR was measured in pure and mixed stands of oak and beech and was partitioned into two contributions using the forest floor removal technique Mineral Soil Respiration MSR and Forest Floor Respiration FFR . In addition laboratory incubations of the forest floor and the Ah horizon were performed to evaluate the heterotrophic respiration and the DOC production of these horizons. The relationships between soil temperature and the various soil respiration contributions in the three stands were compared using Q10 functions. In situ significant differences a 0 05 between stands were observed for the R10 parameter respiration rate at 10 C of the TSR MSR and FFR contributions while only the temperature sensitivity Q10 of TSR was significantly affected by stand composition. The effect of soil water content was only significant on MSR and followed different patterns according to stand composition. Under controlled conditions the R10 of the forest floor and of the Ah horizon varied with stand composition and the Q10 of the forest floor decreased in the order oak mixture beech . soil respiration partitioning species effect mixed stand abiotic factors Résumé - Flux de CO2 en provenance du sol en peuplements purs et melanges de chêne et de hêtre. La respiration totale du sol RTS a été mesurée en peuplements purs et mélangés de chene et de hetre et a été subdivisée en deux contributions en enlevant les couches holorganiques de certaines zones de mesure RSM .