Báo cáo lâm nghiệp: " Predator/prey ratios: a measure of bark-beetle population status influenced by stand composition in different French stands after the 1999 storms" pps
... site.
The comparison of predator/prey ratios between sites and years was
carried out using a two-way analysis of variance of the angular trans-
form of the predator/prey ratio, with the site, year, ... clearly higher in HA
and ST (the two sites with pines) than in GU and 2L, and all
ratios tend to increase with years (two-way ANOVA using arc-
sine-transformed ratios...
... 1998. Allozyme
and RAPD analysis of the genetic diversity and geographic
variation in wild populations of the American chestnut
Castanea dentata (Fagaceae). American Journal of Botany,
85: 1013–1021.
JIMÉNEZ ... is a wide-spread broad-
leaved tree species in the Mediterranean basin. In
Spain, it occupies 2,039,563 ha and the main stands
are found in the south...
... height of highest stem, mean height of the stems; mean and
minimum distance from the ground to the top of the crown; total basal
area (adding together the basal area of all stems); and equivalent ... Iberian Peninsula. In the areas
included in the study, mean annual precipitation ranged from 595 to
853 mm, mean annual water deficit (annual potential evapotranspi-
rati...
... particular since these species
acclimate to limited water availability by increasing their
resistance to cavitation [13], one of the major causes of decline
in the botanical species in the absence of ... of the sigmoïd
curve was characterized by three critical points, , and
which indicated the water potential values that induced the start of the
embolism, 50%...
... simple. In the peripheral layer, where the MS
occur, the axial strain increment ( ) can be split into elastic axial
strain increment ( ) and axial MS ( ). Generalisation at any point
M of is given by:
,
where ... structure was taken as a reference in order to carry out a numer-
ical evaluation of the ITMM biomechanical model. The advantage of
this approach was to con...
... grown in
the shade. A higher number of leaves, larger total leaf area and higher dry matter of leaves per 1 plant were de-
termined in seedlings grown in the sun. The average area of one leaf was ... the shade after transfer to a gap was still
lower after 30 days than in the leaves of plants left
in the shade and in control seedlings growing in the...
... Ager-
atina adenophora: Ageraden; Agrostis castellana: Agrocast; Aira caryophyllea: Airacary; Anagallis arvensis: Anagarve; Aphanes micro-
carpa: Aphamicr; Arrhenatherum elatium: Arrhelat; Asplenium ... with increasing stand age, and mid to late successional
stages (8 to 25 YAH) are discriminated from one another along
Axis 1 on the basis of increasing basal area and aerial biomass
and...
... study was to calculate the accumu-
lation and the export of nutrients over time in Pinus pinaster
(maritime pine) and Pinus radiata (radiata pine) stands under
a range of silvicultural alternatives, ... state of the standard stands over time
allowed to estimate the stand table before and after thinning, and also
the temporal dynamics of nutrient content in tree...
... to aid survival by reducing the risk of intracellu-
lar freezing, owing to the lowering of the cytoplasm freezing
point, and by maintaining cell turgor [11]. These strategies
contribute to increasing ... 14 h.
The resulting frost damage on the surface of the leaves could be visu-
ally observed the following day. Leaf damage (LD) was assessed by
rating the leaves in...
... soil quality in sloping oak
stands we determined several soil physical, chemical and
microbial properties and the abundance of Lumbricidae in
mixed oak-hazel stands and adjacent oak monocultures. ... chosen at random and sampled
in May 2003. The number of individuals per m² was calculated by sum-
ming up the number of earthworms of each single replicate per site.
2.6...