Báo cáo lâm nghiệp: "Infrared images of heat fields around a linear heater in tree trunks: what can be learned about sap flow measuremen" pptx

... 10.1051/forest:2006046 Original article Infrared images of heat fi elds around a linear heater in tree trunks: what can be learned about sap flow measurement? Helmut T a * , Nadezhda N  b ,JanC b a Hahn-Meither ... isotherm of temperature T S parallel to the sap flow direction. In absence of sap flow this axial distan...

Ngày tải lên: 07/08/2014, 16:20

... linear heater in a real tree stem taking place during usual diurnal changes of sap flow; deformation of heat field after abrupt changes of heating (when the heater is switched on and off) under ... image. Similarly the disappearing warm zone remained symmetrical along the axis of the heater at the radial images of the smoothed stem surface (see Fig. 3). 3.2. He...

Ngày tải lên: 08/08/2014, 01:22

... the fauna of cambioxylophages was analyzed both on standing breaks and lying break-off stems. Breaks are characterized by the gradually drying phloem, watered phloem and secondary fauna (Hylurgops ... with sal- vage felling they create local large populations not only on breaks and breaks-off in young stands but also on windfalls and windbreaks in mature stands particularly at sout...

Ngày tải lên: 07/08/2014, 04:20

... procedure of stand origination and by the way of reducing the tree number by natural elimina- tion and systematic measures of forest managers. Man-made stands mostly have the regular original distribution ... characteristics of horizontal structure of natural stands, according to the above author the monitoring of the spatial structure can be used as an indicator of t...

Ngày tải lên: 07/08/2014, 10:21

... mathematical and statistical evaluation of acquired data.  e evaluation of transition matrices describ- ing the probability of a change in the assessment of defoliation of particular trees in ... classes but also on the ob- servation of average defoliation (it was always calcu- lated as the average value of defoliation of all living trees) and/or average foliage (ca...

Ngày tải lên: 07/08/2014, 10:21

... present an approach to estimate stand-level BEFs, both by age-classes (reflecting the available format of source data) and as a single value and to analyse the associated BEF uncertainty for Norway ... range of stand dominant heights was 13.3 to 36.3 m, tree density varied between 120 and 1336 trees/ha and stand basal area was 14.8–73.1 m 2 ha −1 with a mean of 45.9 m 2 ha −1 . 2.2...

Ngày tải lên: 07/08/2014, 16:20

... oak (Quercus suber L.) occupies large areas around the western Mediterranean basin in Southern Europe and North Africa, over a total area of about 2 million ha, mainly in Portugal (725 000 ha) ... (on average 0.10 g cm −3 , Tab. II) and constant radially. 3.5. Analysis of variation of ring and density components An analysis of variance was made on the ring and density compon...

Ngày tải lên: 07/08/2014, 16:20

... Ψπ 0 ) as water availability decreased and PFD increased, allows seedlings to maintain a water potential gradient from the soil to the plant and to facilitate water uptake. Although no interaction ... moderate drought Marta PARDOS a *, M. Dolores JIMÉNEZ a , Ismael ARANDA a , Jaime PUÉRTOLAS b , José A. PARDOS b a CIFOR-INIA, Ap. Correos 8.111, 28080 Madrid, Spain b U.D. Anatom...

Ngày tải lên: 08/08/2014, 00:22

... logs), ultrasound speed was corrected according to Sandoz [31]. 2.3. Statistical analysis The mean by ramet at each stage of sampling was submitted to a variance and a covariance analysis [30] according to the ... samples. Realising the selection on standing trees with an ultrasound method has the advantage of keeping the trees alive but leads to a loss in the gain of the select...

Ngày tải lên: 08/08/2014, 01:22

... pyrenaica can be said to be sensitive to environmental variations, a decrease in stomatal activity having been observed that can sometimes be identified with a certain degree ... of Quercus pyrenaica Willd to environmental factors in two sites differing in their annual rainfall (Sierra de Gata, Spain) M Rico, HA Gallego, G Moreno, I Santa...

Ngày tải lên: 08/08/2014, 18:21