The potentials and limitations of dicotyledonous wood anatomy for climatic reconstructions

Paleobiology ◽  
1993 ◽  
Vol 19 (4) ◽  
pp. 487-498 ◽  
Author(s):  
Elisabeth A. Wheeler ◽  
Pieter Baas
Keyword(s):  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Wood Anatomy ◽  
Vessel Diameter ◽  
Fossil Wood ◽  
Phylogenetic Significance ◽  
Growth Rings ◽  
Past Climate ◽  
Anatomical Features ◽  
Conflicting Information

The incidences of selected features of dicotyledonous wood that are believed to be of ecologic and/or phylogenetic significance (distinct growth rings, narrow and wide vessel diameter, high and low vessel frequencies, scalariform perforations, tangential vessel arrangement, ring porosity, and helical wall thickenings) were plotted through time (Cretaceous–Recent). There are marked differences between the Cretaceous and Tertiary in the frequency of all wood anatomical features. Incidences of features that are associated with markedly seasonal climates in extant floras do not approach modern levels until the Neogene. Correlations of wood anatomical features with ecology do not appear to have been constant through time, because in the Cretaceous different features provide conflicting information about the climate. Throughout the Tertiary the southern hemisphere/tropical and the northern hemisphere/temperate regions differed in the incidences of ecologically significant features and these differences are similar to those in the Recent flora. Possibilities for reliably using dicotyledonous wood for climatic reconstructions appear restricted to the Tertiary and Quaternary. However, at present the fossil wood record for most epochs and regions is too limited to permit detailed reconstructions of their past climate.

Wood anatomy and conductivity in lianas, shrubs and trees of Bignoniaceae

IAWA Journal ◽  
2017 ◽  
Vol 38 (3) ◽  
pp. 412-432
Author(s):  
Caian Souza Gerolamo ◽  
Veronica Angyalossy
Keyword(s):  
Hydraulic Conductivity ◽  
Wood Anatomy ◽  
Growth Habit ◽  
Vessel Diameter ◽  
Lower Percentage ◽  
Hydraulic Efficiency ◽  
Anatomical Features ◽  
Vessel Area ◽  
Water Conduction ◽  
Cambial Variants

This work compares potential xylem hydraulic efficiency among Bignoniaceae lianas, shrubs and trees. Five species from each growth habit were analysed to determine variance among habits based on quantitative and qualitative wood anatomical features. Potential hydraulic conductivity was calculated for each species in order to compare efficiency of water transport. Cambial variants are present in the Bignonieae tribe, as phloem wedges in lianas and phloem arcs in shrubs. Lianas present vessel dimorphism, quantitatively evidenced by the ratio of maximum by minimum vessel diameter of about 20, higher percentage of vessel area and lower percentage of fibres compared with the self-supporting species studied here. Potential hydraulic conductivity is higher in lianas due to the presence of wider vessels and it is hypothesised that the narrow vessels can function as back-up for water conduction when wider vessels are cavitated.

WOOD ANATOMY OF MYRCIARIA, NEOMITRANTHES, PLINIA AND SIPHONEUGENA SPECIES (MYRTEAE, MYRTACEAE)

IAWA Journal ◽  
2013 ◽  
Vol 34 (3) ◽  
pp. 313-323 ◽  
Author(s):  
Gabriel U.C.A. Santos ◽  
Cátia H. Callado ◽  
Marcelo da Costa Souza ◽  
Cecilia G. Costa
Keyword(s):  
Wood Anatomy ◽  
Growth Rings ◽  
Anatomical Features ◽  
Bordered Pits ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Square Cells ◽  
Ray Parenchyma Cells ◽  
Perforation Plates ◽  
Fruit Characters

Myrciaria, Neomitranthes, Plinia and Siphoneugena are closely related genera whose circumscriptions are controversial. The distinctions between Myrciaria vs. Plinia, and Neomitranthes vs. Siphoneugena, have been based on a few fruit characters. The wood anatomy of 24 species of these genera was examined to determine if wood anatomical features could help delimit the genera. It was determined the four genera cannot reliably be separated by wood anatomy alone. Characteristics seen in all four genera are: growth rings usually poorly-defined; diffuse porous; exclusively solitary vessels, usually circular to oval in outline; simple perforation plates; vessel-ray pits alternate and distinctly bordered; fibers with distinctly bordered pits in radial and tangential walls, usually very thickwalled; vasicentric tracheids typically absent; scanty paratracheal parenchyma, sometimes unilateral, and diffuse to diffuse-in-aggregates; chambered crystalliferous axial parenchyma in many species, usually both prismatic and smaller crystals; rays 1–4-seriate, uniseriate rays composed of upright/square cells, multiseriate rays with procumbent body cells and 1 to many marginal rows of upright/square cells; disjunctive ray parenchyma cells usually present.

A Survey of the Fossil Record for Dicotiledonous Wood and its Significance for Evolutionary and Ecological Wood Anatomy

IAWA Journal ◽  
1991 ◽  
Vol 12 (3) ◽  
pp. 275-318 ◽  
Author(s):  
Elisabeth A. Wheeler ◽  
Pieter Baas
Keyword(s):  
Climatic Change ◽  
Fossil Record ◽  
Wood Anatomy ◽  
Fossil Wood ◽  
Ecological Wood Anatomy ◽  
Anatomical Features ◽  
The World

Data on fossil dicotyledonous wood were assembled in order to 1) test the Baileyan model for trends of specialisation in dicotyledonous wood anatomy by addressing the question - were 'primitive' wood anatomieal features (as defined by the Baileyan model) more common in the geologie past than at present?, 2) infer, on a broad geographie scale, past climatie regimes, and long term climatic change, and 3) assess the extent of knowledge of fossil dicotyledonous woods. The resulting database has information on 91 anatomieal features for over 1200 fossil dicotyledonous woods. The incidence of selected anatomical features was plotted through time (by geologie epoch) for the world and for two regional groupings (roughly corresponding to the Laurasian and Gondwanan supercontinents). For comparison to the fossil wood record, the incidence of wood anatomie al features in the Recent flora was obtained from the 5260 record OPCN database for extant dicotyledonous woods.

Wood Anatomy Of Seven Species Of Tachigali (Caesalpinioideae–Leguminosae)

IAWA Journal ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 19-30 ◽  
Author(s):  
Tahysa M. Macedo ◽  
Claudia F. Barros ◽  
Haroldo C. Lima ◽  
Cecília G. Costa
Keyword(s):  
Phylogenetic Analysis ◽  
Wood Anatomy ◽  
Species Level ◽  
Molecular Phylogenetic Analysis ◽  
Phylogenetic Significance ◽  
Anatomical Features ◽  
Or Groups ◽  
Different Types ◽  
Molecular Phylogenetic ◽  
Thin Walled

This article describes the wood anatomy of seven species of Tachigali Aublet with the aim of identifying 1) diagnostic characters at the species level and 2) anatomical features with potential for future combined morphological and molecular phylogenetic analysis. Tachigali species present fibre dimorphism and can be grouped according to the arrangement of the thin-walled fibres: tangential bands of thin-walled fibres alternating with thick-walled fibres, as in T. duckei and T. vulgaris; wavy bands , as in T. paratyensis, T. glauca and T. vulgaris; well-developed bands to describe the abundance of thin-walled fibres in contrast to thick-walled fibres, as in T. denudata and T. pilgeriana; and in islands or groups of thin-walled fibres scattered among ordinary fibres. It is recommended to explore the phylogenetic significance of the different types of fibre dimorphism in future combined molecular and morphological cladistics analyses.

Wood Anatomical Variation of Acacia Melanoxylon in Relation to Latitude

IAWA Journal ◽  
1989 ◽  
Vol 10 (2) ◽  
pp. 201-207 ◽  
Author(s):  
A. P. Wilkins ◽  
Sabine Papassotiriou
Keyword(s):  
Environmental Conditions ◽  
Wood Anatomy ◽  
Anatomical Variation ◽  
Basic Density ◽  
Vessel Diameter ◽  
Axial Parenchyma ◽  
Anatomical Features ◽  
Acacia Melanoxylon ◽  
Eastern Australia ◽  
Total Proportion

The wood anatomy of Acacia melanoxylon samples from various locations in eastern Australia was examined and a number of characteristics were found to be significantly related to latitude. Vessel member length, proportion of fibres and proportion of multiseriate rays were positively related to latitude. Vessel frequency, vessel diameter and the abundance of crystals were negatively related to latitude as were the proportion of: uniseriate rays, vessels and axial parenchyma. Total proportion of ray tissue and basic density was not found to be associated with latitude.Anatomical features associated with lower transpirational demand appeared to be correlated with the cooler, more xeric environmental conditions accompanying increasing latitude.

Anatomical Changes on Charring Six African Hardwoods

IAWA Journal ◽  
1993 ◽  
Vol 14 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Juliet Prior ◽  
Peter Gasson
Keyword(s):  
Wood Anatomy ◽  
Vessel Diameter ◽  
Ecological Wood Anatomy ◽  
Anatomical Features ◽  
Anatomical Changes ◽  
Quantitative Characters ◽  
The Family ◽  
Parenchyma Cells ◽  
Ray Cells ◽  
Quantitative Changes

Charcoal often retains sufficient qualitative anatomical features for the family and genus of the wood to be identified. During the charring process however, considerable and sometimes unexpected changes in quantitative characters occur, which are of particular importance to species identification and ecological wood anatomy. Comparative measurements were made using charred and uncharred trunkwood from six common southern African savanna trees. SampIes were charred for 30 minutes at either 400 or 700°C. Charcoal yield and significant quantitative changes in vessel diameter and ray cells are related both to wood anatomy and to the process of combustion. Differences observed on charring were most closely correlated with the nature and quantity of the fibres. Axial parenchyma cells expanded after charring at both temperatures.

Alpha-Effect, Current and Kinetic Helicities for Magnetically Driven Turbulence, and Solar Dynamo

2000 ◽  
Vol 179 ◽  
pp. 387-388
Author(s):  
Gaetano Belvedere ◽  
V. V. Pipin ◽  
G. Rüdiger
Keyword(s):  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Convection Zone ◽  
Solar Surface ◽  
Momentum Transport ◽  
Angular Momentum Transport ◽  
Magnetic Buoyancy ◽  
Alpha Effect ◽  
Current Helicity

Extended AbstractRecent numerical simulations lead to the result that turbulence is much more magnetically driven than believed. In particular the role ofmagnetic buoyancyappears quite important for the generation ofα-effect and angular momentum transport (Brandenburg & Schmitt 1998). We present results obtained for a turbulence field driven by a (given) Lorentz force in a non-stratified but rotating convection zone. The main result confirms the numerical findings of Brandenburg & Schmitt that in the northern hemisphere theα-effect and the kinetic helicityℋkin= 〈u′ · rotu′〉 are positive (and negative in the northern hemisphere), this being just opposite to what occurs for the current helicityℋcurr= 〈j′ ·B′〉, which is negative in the northern hemisphere (and positive in the southern hemisphere). There has been an increasing number of papers presenting observations of current helicity at the solar surface, all showing that it isnegativein the northern hemisphere and positive in the southern hemisphere (see Rüdigeret al. 2000, also for a review).

The Hemispheric Sign Rule of Current Helicity during the Rising Phase of Cycle 23

2000 ◽  
Vol 179 ◽  
pp. 303-306
Author(s):  
S. D. Bao ◽  
G. X. Ai ◽  
H. Q. Zhang
Keyword(s):  
Solar Cycle ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Active Regions ◽  
Hemispheric Preference ◽  
Current Helicity

AbstractWe compute the signs of two different current helicity parameters (i.e., αbestandHc) for 87 active regions during the rise of cycle 23. The results indicate that 59% of the active regions in the northern hemisphere have negative αbestand 65% in the southern hemisphere have positive. This is consistent with that of the cycle 22. However, the helicity parameterHcshows a weaker opposite hemispheric preference in the new solar cycle. Possible reasons are discussed.

FEEDBACK OF WATER STRESS ON WOOD PROPERTIES OF TREES: EXPERIMENTS WITH MISTLETOES ON RHODODENDRON ARBOREUM SM.

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohan P. Devkota ◽  
Gerhard Glatzel
Keyword(s):  
Water Stress ◽  
Wood Anatomy ◽  
Wood Properties ◽  
Vessel Diameter ◽  
Conservation Area ◽  
Rhododendron Arboreum ◽  
Central Nepal ◽  
Inhibition Of Growth ◽  
Infected Area ◽  
Anatomical Parameters

Effects of infection by the mistletoe Scurrula elata (Edgew.) Danser, on wood properties of its common host Rhododendron arboreum Sm., were studied in the Annapurna Conservation Area of Central Nepal Himalaya. Heavy infection by mistletoes invariably causes decline of the host. Infested branches show inhibition of growth, defoliation and eventual death of branch parts distal to the site of infection. Anatomical properties of wood were compared in samples of branches proximal to the infection and in uninfected branches. The hypothesis that infection induces changes in basic wood anatomy could not be proven. Vessel density, vessel area, percentage lumen area and mean vessel diameter of the wood of infested and uninfected branches did not show any significant differences. The studied anatomical parameters were not correlated to the diameter of the host branch. These results show that infection by S. elata did not cause any changes in basic wood anatomy of its host R. arboreum. It appears that the studied anatomical parameters of Rhododendron wood are fairly stable and are not changed by stress due to infection by mistletoes. The damage to the host distal to the infected area most likely results from an insufficiency of total conductive area to supply both mistletoe and host. Unfortunately we could not determine annual conductive area increment, because R arboreum does not develop usable annual tree rings in the climate of the study area. Key words: Himalayas, mistletoe. Rhododendron arboreum, Scurrula elata, water stress, wood anatomy. Ecoprint Vol.11(1) 2004.

scholarly journals First results of low frequency electromagnetic wave detector of TC-2/Double Star program

2005 ◽  
Vol 23 (8) ◽  
pp. 2803-2811 ◽  
Author(s):  
J. B. Cao ◽  
Z. X. Liu ◽  
J. Y. Yang ◽  
C. X. Yian ◽  
Z. G. Wang ◽  
...  
Keyword(s):  
Electromagnetic Wave ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Geomagnetic Storms ◽  
Low Frequency ◽  
Wave Detector ◽  
Ion Cyclotron Waves ◽  
Satellite Platform ◽  
Ion Cyclotron ◽  
First Results

Abstract. LFEW is a low frequency electromagnetic wave detector mounted on TC-2, which can measure the magnetic fluctuation of low frequency electromagnetic waves. The frequency range is 8 Hz to 10 kHz. LFEW comprises a boom-mounted, three-axis search coil magnetometer, a preamplifier and an electronics box that houses a Digital Spectrum Analyzer. LFEW was calibrated at Chambon-la-Forêt in France. The ground calibration results show that the performance of LFEW is similar to that of STAFF on TC-1. The first results of LFEW show that it works normally on board, and that the AC magnetic interference of the satellite platform is very small. In the plasmasphere, LFEW observed the ion cyclotron waves. During the geomagnetic storm on 8 November 2004, LFEW observed a wave burst associated with the oxygen ion cyclotron waves. This observation shows that during geomagnetic storms, the oxygen ions are very active in the inner magnetosphere. Outside the plasmasphere, LFEW observed the chorus on 3 November 2004. LFEW also observed the plasmaspheric hiss and mid-latitude hiss both in the Southern Hemisphere and Northern Hemisphere on 8 November 2004. The hiss in the Southern Hemisphere may be the reflected waves of the hiss in the Northern Hemisphere.

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