Báo cáo lâm nghiệp: "On the durability of Burkea africana heartwood: evidence of biocidal and hydrophobic properties responsible for durability" ppt

... by measuring the diameter of the colony estimated from the mean of two perpendic- ular diameters and expressed as a percentage of the room available for growth, i.e. the diameter of the dish. Growth ... Independently of the nature of the extraction, weight losses observed on Burkea africana blocks are weak, while beech blocks are strongly degraded. These re...

Ngày tải lên: 08/08/2014, 01:22

... end of April to the end of October and emptied in two-week or one month intervals during the period 2001–2006. e sawflies were determined according to the key of V (2002) and the ... started in the stud- ied localities at the end of May or at the beginning of June depending on the actual weather. C. alpina flew first, followed by C. erythrogaster and...

Ngày tải lên: 07/08/2014, 03:22

... beech forests, (ii) to investigate the dependency of these parameters on bedrock type and soil acidity, and (iii) to analyse the importance of the organic layer for the nutrient status of beech forests. ... K) t and base saturation in the mineral soil are key factors for the accumulation of C and N in the organic layer. The total pool of phosphorus was pa...

Ngày tải lên: 08/08/2014, 00:22

... that the age of maximum response depends on the age of the stand at time of thinning (A t )andk. Details of the characteristics of this TRF can be found in Liu et al. [7]. Equation (5) has all the ... (I), and the age at the time of thinning (A t ) are known. Since the parameters α, r and k known (estimated values), the right hand side of the equation can...

Ngày tải lên: 08/08/2014, 00:22

... simulated because the value of the DV was out of the range of the possible development of the stand. Figure 12. Sensitivity of the optimal management schedule to increasing and decreasing harvesting ... patterns of income are important, the optimum treatment of a stand will depend on the rest of the forest property, calling for forest-level management pl...

Ngày tải lên: 08/08/2014, 01:21

... percentage of cover of the tree layer led to the same results, i.e., significant negative correlations for saplings and non-significant ones for seedlings. On the contrary, the cover percentage of the ... energy and forestry costs (i.e. soil preparation, direct sow- ing, supplementary planting and regulation of tree composition) [26]. For the development of m...

Ngày tải lên: 08/08/2014, 01:22

... 3. Standard error of the poststratified mean for systematic and random sampling, the latter compared with the rooted mean variance estimate of the k replicated simple random samples and y V  ... 3. Standard error of the poststratified mean for systematic and random sampling, the latter compared with the rooted mean variance estimate of the k replicate...

Ngày tải lên: 07/08/2014, 03:22

... average weather conditions in Germany). Fur- thermore, due to the unfavourable soil physical and soil chemical properties of the overburden materi- als, most of the mine soils are of low fertility ... ef- fect between the trees and the crop. An increase of the negative competition effect with time, such as reported by J et al. (2000), cannot be excluded because...

Ngày tải lên: 07/08/2014, 10:21

... population N(0). The starting hypotheses for the model were the following: (a) the forest is in a steady state; (b) the diameter growth curves for each Quality I to III along the 180 years of the study ... semi- logarithmic form, but rather has to fulfil the condition that, for each diameter class, the number of trees incoming from the next class below must equal...

Ngày tải lên: 07/08/2014, 16:21

... radius of the stem measured above the branch at the height h i and α is the branch insertion angle. between the height of insert point of the highest branch and the height of insert point of the ... hr is the calculated height of insert point of the branch to the pith, hm is the measured height of insert point of the branch to the trunk, r i+1...

Ngày tải lên: 07/08/2014, 16:21