The influence of wind on ring width and cell length in conifer stems

1970 ◽  
Vol 48 (2) ◽  
pp. 255-259 ◽  
Author(s):  
M. W. Bannan ◽  
M. Bindra
Keyword(s):  
Radial Growth ◽  
Inverse Relationship ◽  
Ring Width ◽  
Cell Length ◽  
Prevailing Wind ◽  
The West ◽  
West Side ◽  
Wind Action ◽  
The Difference

In the three species studied, inequalities were noted in amount of radial growth around the stem. Rings tended to be wider on the east than on the west side. Because the prevailing wind is from the west, the eccentricity is interpreted as being due to wind action. In keeping with the general inverse relationship between ring width and cell length, the cells were longest on the west side where the rings were narrowest. The difference in cell length was not relatable to diversity in frequency of multiplicative divisions in the cambium.

CAMBIAL BEHAVIOR WITH REFERENCE TO CELL LENGTH AND RING WIDTH IN PINUS STROBUS L.

1962 ◽  
Vol 40 (8) ◽  
pp. 1057-1062 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Inverse Relationship ◽  
Ring Width ◽  
Pinus Strobus ◽  
Growth Patterns ◽  
Cell Length ◽  
Annual Rings ◽  
Forest Types ◽  
Thuja Occidentalis ◽  
Cambial Cells ◽  
Individual Trees

The relationships between width of annual rings, length of wood cells, and frequency of anticlinal (multiplicative) divisions in fusiform cambial cells were studied by reference to trees of various growth patterns. The trees selected ranged from 8 to 20 in. diameter and included both open-grown specimens with branches close to the ground and forest types with tall, slender shafts. Much fluctuation was noted among individual trees, but in general there was, in the peripheral growth, an inverse relationship between length of wood cells and width of annual rings. The frequency of anticlinal divisions in the cambium remained at a more or less uniform rate in trees with rings from 1.5 to 5 mm wide, but rose sharply when ring width fell below 1.3 mm. This was in contrast to the situation observed earlier in Thuja occidentalis where the rise in frequency of anticlinal divisions was slight and occurred only in trees with rings less than 0.3 mm wide.

scholarly journals Retroflection from a double slanted coastline – a model for the Agulhas leakage variability

2010 ◽  
Vol 7 (4) ◽  
pp. 1209-1244
Author(s):  
V. Zharkov ◽  
D. Nof ◽  
W. Weijer
Keyword(s):  
South African ◽  
Eastern Coast ◽  
East Side ◽  
The South ◽  
The West ◽  
West Side ◽  
Agulhas Current ◽  
Nonlinear Analytical Model ◽  
The Difference ◽  
Kink Model

Abstract. The Agulhas leakage to the South Atlantic (SA) exhibits strong anti-correlations with the mass flux of the Agulhas Current. This is accompanied by the migration of the Agulhas retroflection whose normal position (NPR) is near Cape Agulhas, where the slant of the South African coast is very small. During periods of strong incoming flux (SIF), the retroflection shifts upstream to Port Elizabeth or East London, where the coastline shape has a "kink", i.e., the slant changes abruptly from small on the west side, to large (about 55°) on the east side. Here, we show that the variability of rings shedding maybe attributed to this kink. To do so, we develop a nonlinear analytical model for retroflection near a coastline that consists of two sections, one strongly slanted (corresponding to the east side) and the other zonal (corresponding to the west side). The principal difference between this and the model of a single straight slanted coast discussed in our earlier papers is that a free purely westward propagation of eddies along the zonal coastline section is allowed in the kinked case. This introduces the interesting situation where the strong slant of the coast east of the kink prohibits the formation and shedding of rings whereas the coast west of the kink encourages such shedding. Therefore, the kink model "locks" the position of the retroflection forcing it to occur just downstream of the kink. That is, rings are necessarily shed from the retroflection area in our kinked model, regardless of the eastern coast slant. By contrast, the application of "no-kink" model for an "averaged" slant (at the same point as the kink) leads to the conclusion that shedding is almost completely arrested by the slant. We suggest that the difference between the intensities of rings shedding during NPR and SIF is due to the shift in the zero curl line in respect to the kink. When the zero curl intersects the coast north of the kink the transport is small but it is large when the zero curl is situated south of the kink. Simple process-oriented numerical simulations are in fair agreement with our results.

scholarly journals La datation du choeur de l’église de Vaucelles reproduit en plan par Villard de Honnecourt

2018 ◽  
Vol 81 (3) ◽  
pp. 411-417
Author(s):  
Laurence Terrier Aliferis
Keyword(s):  
Nineteenth Century ◽  
Historical Sources ◽  
The West ◽  
West Side ◽  
Villard De Honnecourt ◽  
The Church

Abstract The ruined Cistercian church of Vaucelles is known only by a few preserved fragments and a plan of the choir reproduced by Villard of Honnecourt. Historical sources provide three key dates: 1190 (start of construction), 1215 (entry into the new church), 1235 (date of the dedication). From the nineteenth century until now, it was considered that the foundations were laid in 1190 and that the construction started on the west side of the church. In 1216, the nave would have been completed, and the choir would have been built between 1216 and 1235. Consultation of the historical sources and examination of the historiographic record changes this established chronology of the site. In fact, the construction proceeded from east to west. The choir reproduced in 1216 or shortly before by Villard de Honnecourt presents the building as it then appeared, with the eastern part of the building totally completed.

St Audrie's Bay, Somerset, England: a candidate Global Stratotype Section and Point for the base of the Jurassic System

1994 ◽  
Vol 131 (2) ◽  
pp. 191-200 ◽  
Author(s):  
G. Warrington ◽  
J. C. W. Cope ◽  
H. C. Ivimey-Cook
Keyword(s):  
Type Locality ◽  
International Commission ◽  
The West ◽  
West Side ◽  
Type Area ◽  
Jurassic System ◽  
Stratotype Section

AbstractIn 1967 the Somerset coastline near Watchet was proposed as the type area of the basal (Planorbis) chronozone of the Hettangian Stage and thus of the Jurassic System. Neither at that time nor subsequently, however, has a type locality and section been nominated from those available in the area. There is urgent need to select a Global Stratotype Section and Point (GSSP) for the base of the Hettangian, and of the Jurassic System. The cliff forming the headland at the west side of St Audrie's Bay, three kilometres east of Watchet, Somerset, is here proposed as the type locality and section, with the base of the Hettangian Stage, at the base of the Planorbis Chronozone, being placed at the horizon currently recognized as that at which ammonites of the genus Psiloceras appear. In this section the base of the Planorbis Chronozone corresponds with the base of the Psiloceras planorbis Biozone. The proposal of this section is conditioned by the availability of comprehensive litho- and biostratigraphic information, and the ability of the section to fulfil International Commission on Stratigraphy (ICS) requirements for a candidate GSSP.

Using reflection seismic method to estimate the fluid dynamics parameters related to wakes

2021 ◽  
Author(s):  
Wenhao Fan ◽  
Haibin Song ◽  
Kun Zhang ◽  
Yi Gong ◽  
Shun Yang ◽  
...  
Keyword(s):  
Potential Vorticity ◽  
Negative Potential ◽  
Distribution Area ◽  
The West ◽  
West Side ◽  
Reflection Seismic ◽  
Vorticity Distribution ◽  
Positive Vorticity ◽  
Coherent Vortices ◽  
Survey Line

<p>In this study, when using reflection seismic data to study the wakes of the Batan Islands, a method for estimating the fluid dynamics parameters such as the relative vorticity (relative Rossby number) and the relative potential vorticity is proposed. Although the relative Rossby number estimation method proposed in this study cannot guarantee absolute accuracy in the calculation value, this method is more accurate in describing the positive and negative vorticity distribution for the wakes, and the resolution of the positive and negative vorticity distribution described by this method is higher than the result of the reanalysis data. For the wakes developed in the Batan Islands, the reflection events in the wake development area have the larger inclination than the reflection events in the western Pacific water distribution area. It is also found that the negative vorticity wakes are mainly distributed on the west side of the island/ridge, and the positive vorticity wakes are mainly distributed on the east side of the island/ridge. This is consistent with the understanding of previous wakes simulations. The strong vorticity values in the study area are mainly distributed at depths above 300m, and the maximum impact depth of wakes can reach 600m. At the downstream position of the wake on the survey line 7, it can be seen that the bottom boundary layer has separated, and there is the negative vorticity wakes on the west side intruding into the positive vorticity wakes on the east side , which is presumed to be caused by the disturbance of the small anticyclone existing near the Batan Islands. For the survey line 7, the negative potential vorticity is mainly distributed on the west side of the island/ridge, and the influence range can reach the sea depth of 600m. In the negative potential vorticity region, there is strong energy dissipation and vertical shear. In this study, we don’t find the existence of submesoscale coherent vortices on the survey line 7, but find the reflection structure similar to filaments on the seismic section. Combined with the analysis of the balanced Richardson number angle of survey line 7, we speculate that the wake in the negative potential vorticity distribution area has the characteristics of symmetrical instability, and the symmetrical instability may destroy the process of filaments forming submesoscale coherent vortices.</p>

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