scholarly journals Développement de microorganismes dans le bois de cœur de chêne (Quercus petraea Liebl) au cours du séchage naturel à l'air libre

1997 ◽  
Vol 54 (6) ◽  
pp. 563-571 ◽  
Author(s):  
N Vivas ◽  
K Amrani-Joutei ◽  
Y Glories ◽  
B Doneche ◽  
C Brechenmacher
Keyword(s):  
Quercus Petraea ◽  
Bois De Cœur

scholarly journals Forest defoliator pests alter carbon and nitrogen cycles

2016 ◽  
Vol 3 (10) ◽  
pp. 160361 ◽  
Author(s):  
Anne l-M-Arnold ◽  
Maren Grüning ◽  
Judy Simon ◽  
Annett-Barbara Reinhardt ◽  
Norbert Lamersdorf ◽  
...  
Keyword(s):  
Climate Change ◽  
Leaf Litter ◽  
Soil Microbial Activity ◽  
Quercus Petraea ◽  
Oak Forests ◽  
Operophtera Brumata ◽  
Winter Moth ◽  
Carbon And Nitrogen ◽  
Soil Microbial ◽  
C And N

Climate change may foster pest epidemics in forests, and thereby the fluxes of elements that are indicators of ecosystem functioning. We examined compounds of carbon (C) and nitrogen (N) in insect faeces, leaf litter, throughfall and analysed the soils of deciduous oak forests ( Quercus petraea  L.) that were heavily infested by the leaf herbivores winter moth ( Operophtera brumata  L.) and mottled umber ( Erannis defoliaria  L.). In infested forests, total net canopy-to-soil fluxes of C and N deriving from insect faeces, leaf litter and throughfall were 30- and 18-fold higher compared with uninfested oak forests, with 4333 kg C ha −1 and 319 kg N ha −1 , respectively, during a pest outbreak over 3 years. In infested forests, C and N levels in soil solutions were enhanced and C/N ratios in humus layers were reduced indicating an extended canopy-to-soil element pathway compared with the non-infested forests. In a microcosm incubation experiment, soil treatments with insect faeces showed 16-fold higher fluxes of carbon dioxide and 10-fold higher fluxes of dissolved organic carbon compared with soil treatments without added insect faeces (control). Thus, the deposition of high rates of nitrogen and rapidly decomposable carbon compounds in the course of forest pest epidemics appears to stimulate soil microbial activity (i.e. heterotrophic respiration), and therefore, may represent an important mechanism by which climate change can initiate a carbon cycle feedback.

scholarly journals Improved Deschampsia cespitosa growth by nitrogen fertilization jeopardizes Quercus petraea regeneration through intensification of competition

2018 ◽  
Vol 31 ◽  
pp. 21-32 ◽  
Author(s):  
Antoine Vernay ◽  
Philippe Malagoli ◽  
Marine Fernandez ◽  
Thomas Perot ◽  
Thierry Améglio ◽  
...  
Keyword(s):  
Nitrogen Fertilization ◽  
Quercus Petraea ◽  
Deschampsia Cespitosa

Influence de la densité du couvert forestier sur le développement architectural de jeunes chênes sessiles, Quercus petraea (Matt.) Liebl. (Fagaceae), en régénération forestière

2000 ◽  
Vol 78 (12) ◽  
pp. 1531-1544 ◽  
Author(s):  
Eric Nicolini ◽  
Daniel Barthélémy ◽  
Patrick Heuret
Keyword(s):  
Quercus Petraea ◽  
Growth Unit ◽  
Growth Morphology ◽  
Basal Diameter ◽  
Canopy Density ◽  
Sessile Oak ◽  
The North ◽  
Oak Trees ◽  
Branching Patterns ◽  
Number Of Branches

The growth and branching patterns of the main axis of 6-year-old sessile oak, growing in a natural regeneration in the north of France, were analysed each year retrospectively according to three increasing canopy density conditions: large gap, small gap, and dense canopy. Increasing gap size is associated with an increase in the total height, basal diameter, branching probability, and global polycyclism rate of the trees. At the growth unit or annual shoot level, from dense canopy to large gaps these botanical entities also show an increase in their total length, number of nodes, polycyclism, and branching rate as well as mean number of branches and mean internode length. A discussion of our results revealed some endogenous features of growth and branching patterns in young sessile oak trees. It is also shown that increasing canopy density generally tends to reduce the expression of the endogenous architectural sequence of differentiation of young sessile oak trees. Young trees growing below dense canopy thus seem to be "delayed" in their sequence of differentiation and appear to be in a "waiting" status, whereas young trees growing in large gaps exhibit an architecture very similar to trees growing in nurseries under nonlimiting growth conditions.Key words: architecture, Quercus petraea, growth, morphology, canopy density.

Characterisation, prediction and relationships between different wavebands of solar radiation transmitted in the understorey of even-aged oak (Quercus petraea, Q. robur) stands

Trees ◽  
2006 ◽  
Vol 20 (3) ◽  
pp. 363-370 ◽  
Author(s):  
P. Balandier ◽  
G. Sonohat ◽  
H. Sinoquet ◽  
C. Varlet-Grancher ◽  
Y. Dumas
Keyword(s):  
Solar Radiation ◽  
Quercus Petraea
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