Báo cáo lâm nghiệp: " Modelling the influence of winter frosts the development of the stem canker of red oak, caused by Phytophthora cinnamomi" doc

... further support to the hypothesis that winter frost is the meteorological variable limiting the distribution of the disease. The most

Ngày tải lên: 08/08/2014, 18:21

... larger number of samples is available. The predictive model used the dbh for estimating the width of the red heart shape. Further factors like the mean increase of dbh or the possibilities of oxygen ... the better quality classes A and B, respec- tively. The red heartwood percentage is assessed at the ends of logs as the diameter of the circumcircle of...

Ngày tải lên: 07/08/2014, 16:20

... be one of the biggest advantages of the plenter system [10, 19]. There are evidently limits to this advantage. One of these is the formation of discoloured wood (known as facultative red heartwood). ... in the equilibrium model. According to the rule of sustainability, the sum of removal must correspond to the whole increment (in terms of basal area increment or...

Ngày tải lên: 08/08/2014, 00:22

... tree T3. These gaps can be explained by the delay or advance of the reaction processes. Differences of stress intensity can also result from the different positions of the upper part of the stem ... the stem from the base to the top (i = 1… n+1). Convention states that element is on the left and element i is on the right of node i. The ITMM uses the sta...

Ngày tải lên: 08/08/2014, 01:22

... predictive capacity. Fulfilment of these properties depends on both the con- struction method and the mathematical function used to de- velop the model. Most of them can be achieved by use of the Algebraic ... on the age of the stand and other stand variables (theoretically the productive ca- pacity of the site and any other measure of stand density), it is gener-...

Ngày tải lên: 07/08/2014, 16:21

... number of fittings was equal to the number of trees. Both the mean of the prediction residuals and the mean of the abso- lute prediction residuals were estimated using equation (8) and the bias and ... [4]. The heteroscedasticity associated with the error terms of the models was analysed by plotting the variance of the residuals against the observed value...

Ngày tải lên: 08/08/2014, 00:22

... 1990). On the other hand, Crocq (1990) reported that all of the hidden seeds were recovered afterwards by the spotted nutcracker during poor crop years. The combined action of bird ... (85% of the losses), but 11.8% of the conelets aborted following the attack of P atomarius. Conelet attack by the midge C pini could only be quan...

Ngày tải lên: 08/08/2014, 18:21

... incorporates the influence of aerody- namic and canopy conductances. The for- mer depends on roughness properties of the canopy, and the latter is considered as the sum of the stomatal ... the evening, probably due to a dehydration in the morning of the water exchangeable tissues of the trees (Jarvis, 1975), followed by a rehy...

Ngày tải lên: 08/08/2014, 18:21

... not predicate the spacing of roads. After all, the efficiency of the network would be very different although the value of the road density is similar but as the basic parameter which shows the ... designated by yellow colour in the map, transport roads of the 1 st grade by red, transport roads of the 2 nd grade by blue and skidding roads placed to...

Ngày tải lên: 07/08/2014, 10:21

... 3). Since the decade of the 1960s there has been a new reduction of grazing intensity and in most of the trees established in the first decades of the 20th century the apex exceeded the brows- ing ... im- portant to remember that the second half of the nineteenth century saw the end of the unfavorable climatic conditions of the Little Ice Age [22]. Other p...

Ngày tải lên: 07/08/2014, 16:20