Growth, wood chemistry, and fibre length of Norway spruce in a long-term nutrient optimization experiment

2009 ◽  
Vol 39 (2) ◽  
pp. 410-419 ◽  
Author(s):  
Seija Kaakinen ◽  
Riikka Piispanen ◽  
Satu Lehto ◽  
Johanna Metsometsä ◽  
Urban Nilsson ◽  
...  

The study was performed as part of a nutrient optimization experiment at Asa in southern Sweden. The experiment was established 1987, in a Norway spruce ( Picea abies (L.) Karst.) stand planted in 1975. In the nutrient optimization treatment (IL), all essential macro- and micronutrients were supplied, with irrigation water, every second day during the growing season. In October 2003, nine trees were harvested on both untreated control and IL plots. The IL treatment increased annual ring width during the first years of the experiment by ca. 30% and cumulative cross-sectional area 1.5-fold by the end of the experiment. Tracheid length was, however, not affected by the IL treatment. The nitrogen concentration of wood increased and starch concentration decreased as an effect of the IL treatment, suggesting that carbon was allocated to growth rather than storage. The IL treatment increased lignin concentration of wood by 3.4%. Chemical composition varied at different heights along the stem, but with no apparent trend.

2020 ◽  
Vol 78 (6) ◽  
pp. 1061-1074 ◽  
Author(s):  
Tadios Habite ◽  
Anders Olsson ◽  
Jan Oscarsson

Abstract Knowledge of annual ring width and location of pith in relation to board cross-sections, and how these properties vary in the longitudinal direction of boards, is relevant for many purposes, such as assessment of shape mechanical properties and stability of sawn timber. Hence, the present research aims at developing a novel method and an algorithm, based on data obtained from optical surface scanning, by which the pith location along the length of sawn timber boards can be determined accurately and automatically. The first step of the method is to identify clear wood sections, free of defects along boards. Then time-frequency analysis, using the continuous wavelet transform, is applied to detect the surface annual ring width distribution of the four sides of the selected sections. Finally, the pith location is estimated by comparing annual ring width distributions on the different surfaces, and assuming that annual rings are concentric circles with the pith in the centre. The proposed algorithm was applied to a total sample of 104 Norway spruce boards. Results indicate that optical scanners and the suggested automatic method allow for accurate detection of annual ring width and location of pith along boards. For a sample of boards with the pith located within the cross-section, a mean error of 2.6 mm and 3.2  mm in the depth and thickness direction, respectively, was obtained. For a sample of boards of which 60% with pith located outside the cross-section, a mean discrepancy between automatically and manually determined pith locations of 3.9 mm and 5.8 mm in depth and thickness direction, respectively, was obtained.


2007 ◽  
Vol 37 (8) ◽  
pp. 1373-1389 ◽  
Author(s):  
Dag Molteberg ◽  
Olav Høibø

Basic density (BD), fibre length (FL), fibre width (FW), and fibre wall thickness (FWT) were investigated in 46 Norway spruce ( Picea abies (L.) Karst.) trees from five different stands in eastern Norway. From each tree, wood samples were collected in different radial and longitudinal positions. Random coefficient mixed models were used to investigate variation within as well as among trees, both within and among stands. The R2 with random effects included, describing the best possible (individual) fit of the observed data to the models, were 0.90 for BD, 0.99 for FL, 0.88 for FW, and 0.91 for FWT. With only fixed effects, the best model explained 56% of the total variation for BD, 94.5% for FL, 61% for FW, and 63% for FWT. A common model for all trees, without tree and site information, predicted FL well but BD, FW, and FWT poorly. Adding site index, breast height diameter, and tree height to the models reduced the residual variance considerably for FW, FWT, and particularly BD, whereas only a minor improvement was gained for FL. The latter type of models might be easier to use for industrial purposes. Although information about ring width gave further improvements, ring width measurements are time consuming and difficult to perform in the forest and in industrial environments.


Holzforschung ◽  
2010 ◽  
Vol 64 (1) ◽  
Author(s):  
Tuula Jyske ◽  
Seija Kaakinen ◽  
Urban Nilsson ◽  
Pekka Saranpää ◽  
Elina Vapaavuori

AbstractThe effects of thinning intensity on wood structure and chemistry of Norway spruce [Picea abies(L.) Karst.] have been studied in a long-term thinning experiment established in the 1960s in south-western Sweden. The experiment comprised datasets of unthinned control trees and trees of four thinning treatments, in which thinning operations of different intensities were carried out. These thinning operations were applied either once, three, or five times over the course of the stand rotation. Thinning intensities varied from 0% to 60% based on the stand basal area (BA) before thinning: (A) 5×20% (i.e., 20% of the BA removed five times); (B) 3×40% (i.e., 40% of the BA removed three times); (C) 1×60% (i.e., 60% of the BA removed once); and (D) 5×40% (i.e., 40% of the BA removed five times). Altogether 60 trees that were 67 years old were sampled 38 years after the treatment onset. Radial growth rate, wood density, tracheid properties, and the chemical composition of wood were studied in detail. All four thinning treatments increased growth rate and decreased wood density; however, treatment D showed the greatest change. Single, heavy thinning in treatment C resulted in unfavourable intra-stem variation in ring width and wood density. No significant differences in tracheid properties and wood chemistry were found between the treatments. We conclude that only a remarkable increase in growth rate would induce detrimental changes in tracheid properties and wood chemistry in the context of thinning.


Holzforschung ◽  
2002 ◽  
Vol 56 (3) ◽  
pp. 239-243
Author(s):  
J. Liu ◽  
X. M. Diao ◽  
T. Furuno

Summary Eight transverse sections of hinoki (Chamaecyparis obtusa Endl.) were analyzed along the grain near a knot by circularity index (CI), aspect ratio and equivalent diameter. The specimens were divided into two groups, one above and one below the knot, and their distances from the knot were 0 mm (the nearest), 12 mm, 24 mm, and 36 mm, respectively. Another sample was also selected from knot-free wood for reference along the same grain. A gradual decrease in the aspect ratio of tracheids demonstrated that both boundaries and lumina tended to have small differences in length and width as they approached the knot along the grain. CIs of lumina nearest to the knot indicated astonishingly high values with a narrow range from hexagon to ellipse, compared with the others ranging from rectangle, via hexagon, to ellipse. In other words, lumina showed a tendency to become round near the knot. In addition, the equivalent diameters of lumina tended to decrease when approaching the knot, implying that cell wall thickening of tracheids occur near the knot. It should be noted that the above variations in tracheids accompanied changes in grain orientation and annual ring width, especially the sharp transformation nearest to the knot.


2019 ◽  
Vol 28 (3) ◽  
pp. e016 ◽  
Author(s):  
Petr Čermák ◽  
Tomáš Kolář ◽  
Tomáš Žid ◽  
Miroslav Trnka ◽  
Michal Rybníček

Aim of study: To assess the crown condition and radial growth of Norway spruce on plots with an increasing frequency and strength of drought during the last decades.Area of the study: Northern Moravia, Czech Republic.Material and methods: Crown condition assessment and dendrochronology analysis were used.Main results: Tree-ring width was significantly influenced mainly by previous autumn and current summer climate. Temporal variability of growth-climate relationship shows that the impact of water sufficiency (precipitation, relative soil water content, drought index) markedly increased mainly during the 2000s and the 2010s. Most of climate-growth relationships were significant only in the last two or three decades. The observed crown condition and their relationships with TRW also indicate stress intensification during the same period. Our results suggest that the water availability was the main factor affecting radial growth, occurrence of negative pointer years and probably also the factor triggering the decline.Research highlights: In these current site and climate conditions, silviculture of Norway spruce is extremely risky in the study area. Our results have also shown that the observed climate change is too dynamic for the long-term forest plans, especially as regards their recommended forest species composition.


2012 ◽  
Vol 51 (No. 12) ◽  
pp. 539-547 ◽  
Author(s):  
S. Wilczyński ◽  
E. Feliksik

Changes in radial increment of Norway spruce in 25 stands more than 100 years old were analysed. Stands were growing on sites of different exposure situated at 450–1,200 m above sea level in the Polish Western Beskids Mountains. In the mid-1990s a considerable increase in annual ring width was observed. The greatest increase occurred in trees growing at the highest altitudes. This phenomenon occurred after a long period of increment decrease at the turn of the 1970s. After 1990 as the annual ring width was increasing, the variation and amplitude of ring width also increased. The cause of a long-term increase in radial increment was the improvement of thermal and pluvial conditions during late winter and early spring having a substantial effect on Norway spruce growth. In the 1990s the period of rapid changes in thermal and pluvial conditions of summer began. After moist and cold summers there were hot and dry summers. This resulted in increased variations and amplitude of the growth responses of Norway spruce and contributed to the weakening of trees above 100 years of age. The increasing break-up of Norway spruce stands growing in the lower mountain zone of the Polish Western Beskids Mountains, observed in recent years, is the final effect of this process.


2002 ◽  
Vol 18 (3) ◽  
pp. 229-241 ◽  
Author(s):  
Kurt A. Heller ◽  
Ralph Reimann

Summary In this paper, conceptual and methodological problems of school program evaluation are discussed. The data were collected in conjunction with a 10 year cross-sectional/longitudinal investigation with partial inclusion of control groups. The experiences and conclusions resulting from this long-term study are revealing not only from the vantage point of the scientific evaluation of new scholastic models, but are also valuable for program evaluation studies in general, particularly in the field of gifted education.


Author(s):  
Dean Keith Simonton

Although psychologists typically see creativity as an individual-level event, sociologists and cultural anthropologists are more likely to view it as a sociocultural phenomenon. This phenomenon takes place at the level of relatively large and enduring collectives, such as cultures, nations, and even whole civilizations. This chapter reviews the extensive research on such macro-level creativity. The review begins with a historical overview before turning to the cross-sectional research on the creative Ortgeist, a subject that encompasses the factors that influence the relative creativity of both preliterate cultures and entire modern nations. From there the chapter turns to role of the Zeitgeist in affecting the creativity of civilizations across time—the rise and fall of creative activity. This research examines both quantitative and qualitative causes that operate both short- and long-term.


2020 ◽  
Vol 11 ◽  
pp. 215013272097774
Author(s):  
Stephanie T. Fulleborn ◽  
Paul F. Crawford ◽  
Jeremy T. Jackson ◽  
Christy J.W. Ledford

Introduction Recent evidence reveals that diabetes and prediabetes (preDM) can be reversed to normal glucose regulation (NGR) through significant weight loss, but how physicians clinically identify the principles of partial and complete remission of diabetes is largely unknown. Methods As part of the cross-sectional omnibus survey conducted in March 2019 at a professional annual meeting in the United States, physician participants answered case scenario questions about the diagnosis and documentation of patients with preDM and type 2 diabetes (T2DM). Results Of the registered conference attendees, 387 (72.7%) responded. When presented with the initial case of preDM, 201 physicians (70.8%) selected R73.03 Prediabetes. In a follow-up encounter with improved lab results, 118 physicians (58.7%) indicated that they would not chart any diabetes-related code and 62 (30.8%) would chart preDM again. When presented with the case of T2DM, 256 physicians (90.1%) indicated E11.0–E11.9 Type 2 Diabetes. In the follow-up encounter, only 38 (14.8%) coded a diagnosis reflecting remission from T2DM to prediabetes and 211 (82.4%) charted T2DM. Conclusion Physicians may be reluctant to document diabetes regression as there is little evidence for long-term outcomes and “downgrading” the diagnosis in the medical record may cause screenings to be missed. Documenting this regression in the medical record should communicate the accurate point on the continuum of glucose intolerance with both the patient and the care team.


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