Báo cáo lâm nghiệp: "Influence of light conditions on the predetermination of foliar characteristics in Betula alleghaniensis Britton" ppsx

... demonstrate that the light conditions to which plants have been exposed have an influence on the development of early leaves the following spring. The conse- quences on ... harvested in mid- August. Chlorophyll content The chlorophyll content of early leaves was also influenced by the light conditions of year n (Fig. 1 For the 1...

Ngày tải lên: 09/08/2014, 04:20

... ADR seems the best and the simplest indicator of the light conditions in which the tree is growing. Our results indicate that a value of ADR = 1, corresponding to a relative irradiance of about ... analyzed using non-linear functions of Table Curve 2d software (SPSS Inc.); the coefficient of determination (r 2 ), the statistical significance of the regression (...

Ngày tải lên: 08/08/2014, 00:21

... Considering that the theoretical response with depth described by the Weibull function permits a changing position of the peak value in flow, the relationship in flow between two sensors in the ... We considered that the variation in VPD day occurred due to the inflow of drier or wetter air (including rainfall events) with changing weather systems as well as the i...

Ngày tải lên: 08/08/2014, 00:21

... and March of the year in question. e standard tree-ring chronology shows an obvious decrease in radial increments starting at the beginning of the 1970s and ending at the end of the 1980s. ... air pollution load the climatic conditions are the factor determining the resulting effect of the synergic in uence of the stressors on the stands. Keywords: O...

Ngày tải lên: 07/08/2014, 03:22

... Variations in environmental conditions induce unequal response of wood density to elevated CO 2 . For example, at ambient temperatures, approxi- mately 60% increase of the air’s CO 2 concentration ... by the Ministry of Environment of the Czech Republic, Project No. VaV/640/18/03, the Ministry of Education, Youth and Sports of the Czech Republic, Project No. 2B06...

Ngày tải lên: 07/08/2014, 03:22

... during the conversion of blue spruce stands even under environmentally highly stressing conditions, (2) to assess the foliar nutrient status of the alder as a precondition of positive in uence ... decrease in height during the winter period through Table 6. Proportion values of nutrition elements to N (=100%) in dry mass of leaves (the 1 st section of the...

Ngày tải lên: 07/08/2014, 04:20

... content by raising the soil reaction (pH) and promoting mineralization of SOM, on the other hand this treatment adds Ca cations into soil and thus increases the probability of the formation ... consequence of silicate weathering. In the 0–10 cm horizon of the limestone variant, the increased content of exchangeable Ca and Mg is in accordance with expectations...

Ngày tải lên: 07/08/2014, 10:22

... partitioning was impaired by flooding especially in leaves. Further experiments will be help- ful to clarify (i) the role of ammonium assimilation pathway in maintaining amino acid content in root ... seedlings remained slightly higher than in control but at day 34 of stress exposure the flooded cotyledons contained 2-fold higher amino acid con- centrations than that of cont...

Ngày tải lên: 08/08/2014, 00:22

... calculated according to variations in the height/width ratio of the cross sec- tion. The influence of the cross section size effect on the first five vibration frequencies is also discussed. 2. THEORETICAL ... rectangular cross section. This new theoretical formulation includes relations based on the three-dimensional elasticity theory and takes the size effect of t...

Ngày tải lên: 08/08/2014, 00:22

... compression test To go further in the investigations, we studied the influence of species on one criterion: E R measured from compression tests. Figure 9 presents the evolution of E R in function of ... which is defined as the maximum stress before the crushing zone (heterogeneous strain) or the stress at the intersection between the linear approxima- tion of...

Ngày tải lên: 08/08/2014, 01:21