Conducting sapwood area, foliage area, and permeability in mature trees of Piceasitchensis and Pinuscontorta

1984 ◽  
Vol 14 (6) ◽  
pp. 940-947 ◽  
Author(s):  
D. Whitehead ◽  
W. R. N. Edwards ◽  
P. G. Jarvis
Keyword(s):  
Vapour Pressure Deficit ◽  
Basal Area ◽  
Water Vapour Pressure ◽  
Mature Trees ◽  
Area Index ◽  
Sapwood Area ◽  
Local Climate ◽  
Significant Difference ◽  
Physiological Analysis ◽  
The Relationship

The relationships between foliage area and sapwood area between trees and within the crowns of 20 Piceasitchensis (Bong.) Carr., provenance Queen Charlotte Island, British Columbia (10 in a control plot and 10 in a plot fertilized with potassium and phosphorus 8 years before harvest) and 10 Pinuscontorta Dougl., provenance Ladysmith trees were examined using a physiological analysis based on Darcy's law. Foliage area index on the fertilized P. sitchensis plot was higher than on the control. The variation of foliage area density with depth in the canopies followed a normal distribution. Relationships between foliage area and sapwood basal area were linear but the slopes were different for the two species. There was no significant difference between the control and fertilized P. sitchensis trees. The relationship between foliage area and the product of sapwood area and permeability was linear and data from the three plots fell on the same line. Sapwood area, permeability, and their product decreased with depth through the crowns of the trees. Within the crowns, relationships between cumulative foliage area and sapwood area, and between cumulative foliage area and the product of sapwood area × permeability were different with species and treatment. A single linear relationship resulted when the product of cumulative foliage area above an internode × the internode length was plotted against sapwood area × permeability for the internode. This suggests that it is the drop in potential across a node and internode rather than the gradient of potential across the internode that is related to the flux of water through tree crowns. The data support the hypothesis that the relationship between foliage area and sapwood area depends on permeability of the sapwood and the local climate through its influence on transpiration rate, particularly via average water vapour pressure deficit of the air and stomatal conductance.

CANOPY CHARACTERISTICS OF CONTRASTING CLONES OF CACAO (THEOBROMA CACAO)

2002 ◽  
Vol 38 (3) ◽  
pp. 359-367 ◽  
Author(s):  
A. J. Daymond ◽  
P. Hadley ◽  
R. C. R. Machado ◽  
E. Ng
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Theobroma Cacao ◽  
Light Interception ◽  
Canopy Architecture ◽  
Mature Trees ◽  
Area Index ◽  
Mean Values ◽  
Extinction Coefficients ◽  
The Relationship

Canopy characteristics (leaf area index, fractional light interception, extinction coefficient) of mature trees of ten clonally propagated cacao cultivars were measured over a period of 14 months at an experiment site in Bahia, Brazil. Differences in leaf area index between clones became more pronounced over time. When an approximately constant leaf area index was reached (after about nine months), the leaf area index varied between clones from 2.8 to 4.5. Clonal differences in the relationship between leaf area index and fractional light interception implied differences in canopy architecture, as reflected by the range of extinction coefficients (mean values ranged from 0.63 for the clone TSH-565 to 0.82 for CC-10). The results demonstrate the potential for breeding more photosynthetically efficient cacao canopies.

Biomass and leaf area in contrasting lodgepole pine forests

1984 ◽  
Vol 14 (2) ◽  
pp. 259-265 ◽  
Author(s):  
John A. Pearson ◽  
Timothy J. Fahey ◽  
Dennis H. Knight
Keyword(s):  
Leaf Area ◽  
Fine Roots ◽  
Lateral Root ◽  
Root Biomass ◽  
Basal Area ◽  
Pine Forests ◽  
Total Biomass ◽  
Area Index ◽  
Sapwood Area ◽  
Dimension Analysis

Bole, branch, foliage, root crown, and lateral root biomass of Pinuscontorta ssp. latifolia (Engelm. ex Wats.) Critchfield forests in southeastern Wyoming were estimated by a combination of aboveground dimension analysis, belowground planar intersect sampling, and soil coring. Total biomass of six stands ≥75 years old ranged from 123 to 180 Mg/ha, and roof:shoot ratios were much higher in two very dense stands than in four more open stands. Average proportions of biomass in boles, branches, foliage, woody roots, and fine roots were 61, 7, 6, 20, and 6%, respectively. Leaf area index ranged from 4.5 to 9.9. Leaf area per unit sapwood area ranged from 0.20 to 0.57 m2/cm2in stands of different densities, ages, and sites. Sapwood area was a more precise predictor of foliage biomass than was basal area for the low to moderate density stands, but was marginally inferior to basal area for two high density stands (>9000 trees/ha).

The role of stand density on growth efficiency, leaf area index, and resin flow in southwestern ponderosa pine forests

2007 ◽  
Vol 37 (2) ◽  
pp. 343-355 ◽  
Author(s):  
Nate G. McDowell ◽  
Henry D. Adams ◽  
John D. Bailey ◽  
Thomas E. Kolb
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Ponderosa Pine ◽  
Basal Area ◽  
Stand Density ◽  
Growth Efficiency ◽  
Resin Flow ◽  
Area Index ◽  
Sapwood Area ◽  
Ponderosa Pine Forests

We examined the response of growth efficiency (GE), leaf area index (LAI), and resin flow (RF) to stand density manipulations in ponderosa pine ( Pinus ponderosa Dougl. ex Laws.) forests of northern Arizona, USA. The study used a 40 year stand density experiment including seven replicated basal area (BA) treatments ranging from 7 to 45 m2·ha–1. Results were extended to the larger region using published and unpublished datasets on ponderosa pine RF. GE was quantified using basal area increment (BAI), stemwood production (NPPs), or volume increment (VI) per leaf area (Al) or sapwood area (As). GE per Al was positively correlated with BA, regardless of numerator (BAI/Al, NPPs/Al, and VI/Al; r2 = 0.84, 0.95, and 0.96, respectively). GE per As exhibited variable responses to BA. Understory LAI increased with decreasing BA; however, total (understory plus overstory) LAI was not correlated with BA, GE, or RF. Opposite of the original research on this subject, resin flow was negatively related to GE per Al because Al/As ratios decline with increasing BA. BAI, and to a lesser degree BA, predicted RF better than growth efficiency, suggesting that the simplest measurement with the fewest assumptions (BAI) is also the best approach for predicting RF.

Seasonal Variation in Stomatal Responses of Two Cultivars of Lychee (Litchi chinenis Sonn)

1992 ◽  
Vol 19 (3) ◽  
pp. 317 ◽  
Author(s):  
D Batten ◽  
J Lloyd ◽  
C Mcconchie
Keyword(s):  
Stomatal Conductance ◽  
Temperature Sensitivity ◽  
Vapour Pressure Deficit ◽  
Sensitivity Coefficient ◽  
Cultivar Differences ◽  
Water Vapour Pressure ◽  
Data Sets ◽  
Diurnal Changes ◽  
Whole Plant ◽  
Significant Difference

The effect of cultivar and environment on the stomatal conductance and plant water relations of lychee (Litchi chinensis Sonn.) was investigated. Diurnal changes in stomatal conductance (gs) and leaf water potentials (Ψ1) were determined for leaves of irrigated trees of cv. 'Bengal' and cv. 'Kwai May Pink' between July and December 1990. Leaves of Bengal always had much higher gs than Kwai May Pink in winter, but as summer approached, this difference became less. Ψ1 values at midday for Bengal were always much lower than for Kwai May Pink. The linear model, E = G(Ψ1-Ψsoil), where E is transpiration rate and G is whole plant conductance, was found to be valid for nearly all the data sets collected. The values of G for Kwai May Pink were higher than for Bengal, especially in summer, and the average values of G (Bengal 4.1 and Kwai May Pink 6.3 mmol H2O m-2 s-1 Mpa-1) indicate that the lychee has a relatively efficient water transport system compared with other fruit tree species. Laboratory measurements of the responses of these cultivars confirmed observed differences in gs in the field. The responses of each cultivar to irradiance (I), leaf temperature (Tl) and leaf-air water vapour pressure deficit (D) were obtained and used to model the orchard data. The equation (see pdf) where Topt is the temperature for maximum gs, gdark is the basal gs in the dark at given T1 and D, and kI, kT and kD are constants fitted by non-linear least squares, provided an acceptable fit for both cultivars (R2 = 0.68 for Bengal and 0.55 for Kwai May Pink). The fit was not improved by including Ψ1 in the model. There was a significant difference between cultivars in kT, the temperature sensitivity coefficient. Possible implications of inter-cultivar differences in temperature sensitivity are discussed.

A comparison of tree water use in two contiguous vegetation communities of the seasonally dry tropics of northern Australia: the importance of site water budget to tree hydraulics

2007 ◽  
Vol 55 (7) ◽  
pp. 700 ◽  
Author(s):  
G. Kelley ◽  
A. P. O'Grady ◽  
L. B. Hutley ◽  
D. Eamus
Keyword(s):  
Leaf Area ◽  
Water Use ◽  
Area Index ◽  
Sapwood Area ◽  
Vegetation Communities ◽  
Tree Water Use ◽  
Eucalypt Forest ◽  
Significant Difference ◽  
Site Water ◽  
Annual Water

Tree water use in two contiguous communities (eucalypt open-forest and Melaleuca paperbark forest) was measured in tropical Australia, over a 2-year period. The aims of the study were to (1) quantify daily and seasonal patterns of water use in each community, (2) compare patterns of water use among the communities and (3) compare relationships among tree size, sapwood area and water use within the two contrasting vegetation communities. Access to deep soil water stores and the effect of run-on from the eucalypt forest resulted in a relatively high pre-dawn water potential throughout the year, particularly for Melaleuca forest. There were no differences in daily rates of water use, expressed on a sapwood area (Q s) basis, between the two eucalypt species examined (Eucalyptus miniata Cunn. Ex Schauer and E. tetrodonta F.Muell) at any time in the eucalypt forest. For both the eucalypt and Melaleuca forests, there was less seasonal variation in water use expressed on a leaf area (Q l) basis than on a Q s basis, and neither year nor season were significant factors in Q l. In the mono-specific Melaleuca forest, Q s was not significantly different between years or seasons. Water use on a Q l basis was similarly not significantly different between years or seasons in the Melaleuca forest. Leaf area index (LAI) of the eucalypt forest was about half of that of the Melaleuca forest throughout the year but sapwood area per hectare was 33% larger in the eucalypt than the Melaleuca forest, despite the basal area of the Melaeuca forest being almost double that of the eucalypt forest. There was no significant difference in stand water use (mm day–1) between eucalypt and Melaleuca forests during 1998; however, in 1999 Melaleuca stand water use was larger than that of the eucalypt forest. Because of the enhanced dry-season availability of water in the Melaleuca forest and its larger LAI, average annual water use of the Melaleuca forest was almost 60% larger than that of the eucalypt forest. Despite differences in Q l, Q s and annual water use between forests, the ratio of LAI to stand water use was similar for all seasons in both forests. The applicability of ‘universal rules’ linking tree water use and tree hydraulics and the importance of ecosystem location on site water budgets and plant adaptations are discussed.

Patterns of leaf area and growing space efficiency in young even-aged and multiaged coast redwood stands

2007 ◽  
Vol 37 (3) ◽  
pp. 617-626 ◽  
Author(s):  
John-Pascal Berrill ◽  
Kevin L. O’Hara
Keyword(s):  
Leaf Area ◽  
Basal Area ◽  
Stem Volume ◽  
Area Index ◽  
Sapwood Area ◽  
Coast Redwood ◽  
Space Efficiency ◽  
Second Growth ◽  
Volume Increment ◽  
Overstory Trees

Projected leaf area estimates were used to predict volume increment and basal area of second-growth coast redwood ( Sequoia sempervirens (D. Don) Endl.) trees on Jackson Demonstration State Forest, Mendocino County, California. Sample plots were established within even-aged and multiaged mixed-species stands. Redwood tree basal area growth was more strongly related to sapwood area than to tree size and differed significantly between canopy strata and overstory stratum crown classes. Projected leaf area was predicted from sapwood area for each tree, and summarized to the stand level, giving a maximum stand leaf area index (LAI) estimate of 14.9 m2/m2. Redwood tree growing space efficiency (GSE; the ratio of stem volume increment to leaf area) was greatest on average among emergent overstory trees, followed by dominant and codominant overstory trees. There was no evidence of declining overstory tree GSE with increasing leaf area over the range of data collected. A nonlinear model predicted increasing understory tree GSE with increasing leaf area. Models that predict basal area and LAI were developed to permit implementation of GSE models from basic inventory data.

Leaf area – sapwood area relationships in adjacent young Douglas-fir stands with different early growth rates

1987 ◽  
Vol 17 (2) ◽  
pp. 174-180 ◽  
Author(s):  
M. A. Espinosa Bancalari ◽  
D. A. Perry ◽  
John D. Marshall
Keyword(s):  
Leaf Area ◽  
Growth Rates ◽  
Ring Width ◽  
Basal Area ◽  
Early Growth ◽  
Douglas Fir ◽  
Sapwood Area ◽  
Breast Height ◽  
Pipe Model ◽  
The Relationship

The relationship between foliage area and sapwood basal area was studied in three adjacent 22-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands that differed in early growth rates. Sapwood width was fairly constant for most of the stem above the stump, but the number of annual rings in the sapwood decreased gradually with height. Sapwood area also decreased with increasing height in the tree, the stands differing significantly only at breast height. The proportion of heartwood from stump to near the base of the crown was significantly higher for the stand of fastest early growth. Ratios of leaf area to sapwood area were significantly higher for that stand and varied in every stem section, the ratio lower at breast height than at the base of the live crown. At the base of the crown, the ratio of leaf area to sapwood area was 1.33 and 1.57 times greater in the fast-growing stand than in the intermediate- and slow-growing stands, respectively. Leaf area was as closely related to dbh as to sapwood area at breast height. Sapwood area at the crown base was more accurate than sapwood area at breast height for predicting leaf area in the fast stand and was equally accurate in the other two stands. Ratios of leaf area to sapwood area correlated positively with sapwood ring width. However, because sapwood ring width also correlated closely with sapwood area, it did not improve predictive equations. The results suggest that the "pipe model" theory must be modified to account for the internal structure of the "pipe" and that caution should be exercised when using published leaf area to sapwood area ratios.

Developing Silvicultural Tools for Managing Mixed Forest Structures in Patagonia

2019 ◽  
Author(s):  
Marina Caselli ◽  
Gabriel Ángel Loguercio ◽  
María Florencia Urretavizcaya ◽  
Guillermo Emilio Defossé
Keyword(s):  
Leaf Area ◽  
Mixed Forest ◽  
Basal Area ◽  
Good Representation ◽  
Mixed Stands ◽  
Mixed Forests ◽  
Area Index ◽  
Sapwood Area ◽  
Allometric Relations ◽  
Prediction Functions

Abstract Leaf area is an important ecophysiological and silvicultural variable for quantifying the potential production of trees, since it can represent growing space occupancy. At the stand level in mixed forests, productivity is conditioned on how growing space is distributed among different components structure, such as species and strata. In complex structures, traditional forest variables (i.e., basal area) do not allow a good representation of the occupied growing space, whereas leaf area appears as a better indicator. Andean cypress and coihue beech are species of the Andean-Patagonian forests that grow in either pure or mixed stands, presenting high productive potential. The aim of this study was to develop, for each species, leaf area prediction functions through allometric relations and to evaluate the relation between leaf area, volume increment and growing space occupancy. For this purpose, we carried out destructive sampling of individuals of both species in mixed Andean cypress-coihue forests. Results for these species show that leaf area can be reliably estimated by using the models developed in this study. These models, based on sapwood area, tree diameter, and/or height measurements, explain at least 90 percent of variation in leaf area. The functions fitted are a fundamental tool to study the distribution of growth and to formulate management guidelines for mixed forests through the control of growing space occupancy using leaf area index.

scholarly journals The relationship between leaf area and basal area growth in jack and red pine trees

1996 ◽  
Vol 72 (2) ◽  
pp. 170-175 ◽  
Author(s):  
Margaret Penner ◽  
Godelieve Deblonde
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Basal Area ◽  
Growth Efficiency ◽  
Jack Pine ◽  
Red Pine ◽  
Area Index ◽  
Sapwood Area ◽  
Basal Area Growth ◽  
Area Growth

Relationships between leaf area and sapwood area, sapwood area and basal area, and leaf area and basal area growth are determined for jack pine and red pine. The relationships vary with species and stand origin. Growth efficiency (basal area growth per unit leaf area) is relatively independent of tree size under all but the densest conditions. Observed changes in the leaf area to leaf mass ratio from July to October indicate that allometric relationships vary seasonally. A procedure is outlined for obtaining estimates of stand leaf area index (LAI). These estimates may be used to calibrate instruments that measure LAI and, subsequently, to predict forest productivity. Key words: leaf area index, basal area, growth efficiency, red pine, jack pine, sapwood area

Relationship between Thyroglobulin and Tumor Detectabilily with Thallium-201 in Differentiated Thyroid Cancer

2000 ◽  
Vol 39 (01) ◽  
pp. 10-15 ◽  
Author(s):  
S. P. Müller ◽  
Ch. Reiners ◽  
A. Bockisch ◽  
Katja Brandt-Mainz
Keyword(s):  
Thyroid Cancer ◽  
Differentiated Thyroid Cancer ◽  
Roc Analysis ◽  
Tsh Suppression ◽  
Significant Difference ◽  
Test Specificity ◽  
The Relationship ◽  
Tumor Scintigraphy ◽  
Tsh Stimulation

Summary Aim: Tumor scintigraphy with 201-TICI is an established diagnostic method in the follow-up of differentiated thyroid cancer. We investigated the relationship between thyroglobulin (Tg) level and tumor detectability. Subject and methods: We analyzed the scans of 122 patients (66 patients with proven tumor). The patient population was divided into groups with Tg above (N = 33) and below (N = 33) 5 ng/ml under TSH suppression or above (N = 33) and below (N = 33) 50 ng/ml under TSH stimulation. Tumor detectability was compared by ROC-analysis (True-Positive-Fraction test, specificity 90%). Results: There was no significant difference (sensitivity 75% versus 64%; p = 0.55) for patients above and below 5 ng/ml under TSH suppression and a just significant difference (sensitivity 80% versus 58%; p = 0.04) for patients above and below 50 ng/ml under TSH stimulation. In 18 patients from our sample with tumor, Tg under TSH suppression was negative, but 201-TICI-scan was able to detect tumor in 12 patients. Conclusion: Our results demonstrate only a moderate dependence of tumor detectability on Tg level, probably without significant clinical relevance. Even in patients with slight Tg elevation 201-TICI scintigraphy is justified.

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