Báo cáo lâm nghiệp:"Effects of field vegetation control on pine weevil (Hylobius abietis) damage to newly planted Norway spruce seedlings" ppt

... SE. Field vegetation control and pine weevil damage 671 colonisation following scarification is an important factor to consider when attempting to reduce pine weevil damage. The vegetation cover ... article Effects of field vegetation control on pine weevil (Hylobius abietis) damage to newly planted Norway spruce seedlings Göran ÖRLANDER...

Ngày tải lên: 08/08/2014, 01:21

... to medium levels of vegetation cover significantly reduced height and diameter growth of white spruce compared to growth on plots with no competing vegetation. At Fort Richardson, saplings on ... We selected vegetation management treat- ments that would result in an array of competing conditions from minimal vegetation (weed-free) to natural development of competin...

Ngày tải lên: 08/08/2014, 01:21

... suppression of the canopy which favoured the dry deposition of N due to the filtering capa- city of the canopy of the mature stand [7]. As dry deposition was not quantified on ground vegetation after ... different patterns of residual nitrates in soil solu- tions, rate of nitrification in laboratory incubations, and struc- ture of microbial populations. Once again Douglas-...

Ngày tải lên: 08/08/2014, 01:21

... plantations and was similar to those in the aban- doned coppice forest (Fig. 4). These results suggest that long- rotation plantations might provide better conditions for the colonization of species ... the plan- tation. Thus, comparison of plantations with abandoned cop- pice forest should help determine whether long rotation can mitigate the effects of standard rotation in plantatio...

Ngày tải lên: 08/08/2014, 01:22

... Indeed, variations of cytosolic-free Ca2+ in guard cells are thought to link stomatal movements to the variations in environmental conditions (reviewed by Mansfield et al, 1990). ... rates (A), stom- atal conductance to CO 2 (g c) or to water vapour (g w ), and the substomatal CO 2 concentration (c i) were calculated following the equation of...

Ngày tải lên: 08/08/2014, 18:21

... Stomatal conductance, photosynthesis and respiration of temperate deciduous tree seedlings grown outdoors at an elevated concen- tration of carbon dioxide. Plant Cell Environ ... may be due to an acclimation to elevated CO 2, similar to the one described by El Kohen et al (1993) on Castanea sativa. The enhancement of net photosynthesis only...

Ngày tải lên: 08/08/2014, 18:21

... article Influence of cross section dimensions on Timoshenko’s shear factor – Application to wooden beams in free-free flexural vibration Loïc BRANCHERIAU* CIRAD - Forêt, TA10/16, Av. Agropolis, 34398 Montpellier ... distribution over the cross section. A new theoretical formulation of the shear factor is thus proposed to assess rectangular cross sections of orthotropic material s...

Ngày tải lên: 08/08/2014, 00:22

... changes of vegetation. To guarantee some homo- geneity among the set of studied sites, only one main type of soil was considered: non-hydromorphic acidic soil. This study was based on vegetation surveys, ... micro-depression) of the sample plot. Species which could not be identified in the field were brought to the laboratory for definitive identification. All vegetation...

Ngày tải lên: 08/08/2014, 01:21

... [42] and competition effects on germination of therophytes described by Pausas et al. [32]. As a conclusion to this study, in spite of the intense modifi- cation of vegetation structure just ... Decrease of intra- and inter-specific competition effects must be considered for foresters in managing of early stages of succession after fire. When it’s considered both vegetation...

Ngày tải lên: 08/08/2014, 01:22

... characteristics of sea- sonal and ontogenetic changes in the tissue-water relations of Acer, Populus, Tsuga, and Picea. Can. J. Bot 56, 635-647 Effects of long-term water stress on net ... steady state conditions in the lab with fixed values of air humidity, daily integrals of WSD seem to be more useful under field conditions, since they...

Ngày tải lên: 09/08/2014, 04:20