The use of electrical capacitance to determine growth and vigor of spruce and fir trees and stands in New Brunswick

1988 ◽  
Vol 18 (5) ◽  
pp. 587-594 ◽  
Author(s):  
R. Glenn MacDougall ◽  
David A. MacLean ◽  
Robert G. Thompson

A capacitance meter based on an integrating operational amplifier design was used to measure electrical capacitance of over 3400 trees in 90 spruce–fir stands in New Brunswick. Trends of capacitance were compared with trends of tree growth, tree characteristics, and defoliation by spruce budworm (Choristoneurafumiferana (Clem.)). Capacitance differed among tree species, with balsam fir (Abiesbalsamea (L.) Mill.) and white spruce (Piceaglauca (Moench) Voss) having generally higher values than red spruce (Picearubens Sarg.) and black spruce (Piceamariana (Mill.) B.S.P.). Capacitance also decreased with crown class and with increasing cumulative defoliation. Correlations between tree growth and capacitance ranged from about 0.6 to 0.7 for tree data, and 0.6 to 0.9 for stand data. Regressions between mean growth per stand and mean capacitance explained about 40 to 70% of the variability in growth. These results indicate that it is practical to use electrical capacitance measurements to assess tree growth and vigor.

1981 ◽  
Vol 11 (1) ◽  
pp. 124-131 ◽  
Author(s):  
E. K. Morgenstern ◽  
A. G. Corriveau ◽  
D. P. Fowler

Survival and total height of red spruce (Picearubens Sarg.) at ages 15 and 22 years from seed are reported. Twelve provenances distributed from North Carolina to Quebec were grown in three experiments each in Ontario, Quebec, and New Brunswick; seven additional provenances were only partially represented. Variance, correlation, and regression analyses were made. Results at both ages were very similar. Provenance differences in survival were small at individual sites and significant only when the results from all nine sites were combined. Provenance differences in height were well expressed and significant in each of the three groups of tests, with northern provenances growing best. Several provenances were also relatively stable and performed well from site to site. Correlation and regression analyses showed that variation in height was more closely related to the degree of introgressive hybridization with black spruce (Piceamariana (Mill.) B.S.P.) than to latitude, elevation, or precipitation at the place of seed origin. These results were conditioned by development on open sites which are not typical red spruce sites.In contrast with expectations when the study was initiated, it is now apparent that provenances from the southern Appalachian Mountains in West Virginia and North Carolina are less variable than expected and not suitable for reforestation in Canada.


1972 ◽  
Vol 2 (4) ◽  
pp. 381-391 ◽  
Author(s):  
S. A. M. Manley

The data obtained by rating 50 plots in red × black spruce populations throughout central New Brunswick with a hybrid index indicate that red and black spruces have hybridized extensively. In the New Brunswick Lowland, gentle slopes and flat uplands form a continuum between characteristic habitats, permitting extensive contact between the two species. Where a considerable zone of contact was present, hybrid populations were established. Selection pressure is apparently strong, for despite the ideal opportunities for contact and the fertility of the hybrids, parental species remain phenotypically pure in their respective characteristic habitats (as far as these could be defined). The composition of hybrid populations was related to the extent of resemblance of 'intermediate' sites to parental site preferences. Introgressed black spruce predominated in hybrid populations, possibly due to the overriding influence of disturbances such as fire, logging, and damage to red spruce types by spruce budworm.


1980 ◽  
Vol 56 (4) ◽  
pp. 155-160 ◽  
Author(s):  
D. P. Fowler ◽  
J. F. Coles

Results from ten provenance trials of Norway spruce in the Maritimes Region are reviewed. Norway spruce from eastern Poland and from mid-elevations in the Sudeten and Carpathian Mountains of northern Poland can be expected to perform well when planted over a wide range of sites in central and southern New Brunswick, Prince Edward Island and Nova Scotia. Norway spruce from east of the Baltic Sea, i.e., northeastern Poland, Latvia, Lithuania, western Russia and White Russia is recommended for northern New Brunswick. These same provenances are recommended for use in Great Lakes — St. Lawrence Region of Quebec and Ontario.Survival and growth rate of Norway spruce are compared to that of native spruce species. In general, survival of black and Norway spruce was the same and exceeded that of white and red spruce. Black spruce was taller than Norway which was taller than white and red spruce in most tests. It is suggested that growth of Norway spruce will exceed that of native spruces over rotations of 40-50 years.


2013 ◽  
Vol 43 (3) ◽  
pp. 266-277 ◽  
Author(s):  
E. Duchateau ◽  
F. Longuetaud ◽  
F. Mothe ◽  
C. Ung ◽  
D. Auty ◽  
...  

Existing models for describing knot morphology are typically based on polynomial functions with parameters that are often not biologically interpretable. Hence, they are difficult to integrate into tree growth simulators due to the limited possibilities for linking knot shape to external branch and tree characteristics. X-ray computed tomography (CT) images taken along the stems of 16 jack pine (Pinus banksiana Lamb.) trees and 32 black spruce (Picea mariana (Mill.) B.S.P.) trees were used to extract the three-dimensional shape of 3450 and 11 276 knots from each species, respectively. Using a nonlinear approach, we firstly fitted a model of knot geometry adapted from a Weibull function. Separate equations were used to describe both the curvature and the diameter of the knot along its pith. Combining these two equations gave an accurate representation of knot shape using only five parameters. Secondly, to facilitate the integration of the resulting model into a tree growth simulator, we extracted the parameters obtained for each knot and modelled them as functions of external branch and tree characteristics (e.g., branch diameter, insertion angle, position in the stem, tree height, and stem diameter). When fitted to a separate data set, the model residuals of the black spruce knot curvature equation were less than 2.9 mm in any part of the knot profile for 75% of the observations. The corresponding value from the diameter equation was 2.8 mm. In jack pine, these statistics increased to 5.4 mm and 3.2 mm, respectively. Overall, the ability to predict knot attributes from external tree- and branch-level variables has the potential to improve the simulation of internal stem properties.


1966 ◽  
Vol 98 (3) ◽  
pp. 239-241 ◽  
Author(s):  
Peter W. Price

AbstractComparative studies on breeding and survival of Polygraphus rufipennis (Kirby) in black spruce, Picea mariana (Mill.) BSP., red spruce, P. rubens Sarg, and white spruce, P. glauca (Moench) Voss, indicate that red spruce is the most favourable host. The thicker, more scaly bark of red spruce and the less frequent occurrence of competition for bark space and food by other organisms are considered as contributory to the success of beetles in this host tree.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christoph Kandlbinder-Paret ◽  
Alice Fischerauer ◽  
Gerhard Fischerauer

Abstract In electrical capacitance tomography (ECT), the resolution of the reconstructed permittivity distribution improves with the number of electrodes used whereas the number of capacitance measurements and the measurement time increases with the number of electrodes. To cope with this tradeoff, we present a phantom-dependent adaptation scheme in which coarse measurements are performed with terminal electrodes interconnected to form a synthetic electrode ring with fewer but larger electrodes. The concept was tested by observing the sloshing of water inside a pipe. We compare the reconstructed results based on eight synthetic electrodes, on 16 elementary electrodes, and on the adaptation scheme involving both the eight synthetic electrodes and some of the elementary capacitances. The reconstruction used the projected Landweber algorithm for capacitances determined by a finite-element simulation and for measured capacitances. The results contain artefacts attributed to the influence of the high permittivity of water compared to the low permittivity of the pipe wall. The adaptation scheme leads to nearly the same information as a full measurement of all 120 elementary capacitances but only requires the measurement of 30 % fewer capacitances. By detecting the fill level using a tomometric method, it can be determined within an uncertainty of 5 % FS.


2007 ◽  
Vol 37 (11) ◽  
pp. 2380
Author(s):  
S. Y. Zhang ◽  
Gilles Chauret ◽  
D. Edwin Swift ◽  
Isabelle Duchesne

1997 ◽  
Vol 6 (8) ◽  
pp. 725-734 ◽  
Author(s):  
M. Perron ◽  
J. Bousquet

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