Wood density as a screening trait for drought sensitivity in Norway spruce

2014 ◽  
Vol 44 (2) ◽  
pp. 154-161 ◽  
Author(s):  
S. Rosner ◽  
J. Světlík ◽  
K. Andreassen ◽  
I. Børja ◽  
L. Dalsgaard ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Wood Density ◽  
Heat Waves ◽  
Drought Event ◽  
Pressure Potential ◽  
Data Set ◽  
Cambial Age ◽  
Hydraulic Vulnerability ◽  
Southern Norway ◽  
The Impact

We linked hydraulic vulnerability in Norway spruce (Picea abies (L.) Karst.) trunkwood with different cambial age to wood density and applied the findings on annual density variations in healthy and declining trees from southern Norway during 1990 to 2010. We hypothesized that drought stress due to the 2003 or 2006 European heat waves were the triggers for tree decline and focused analyses on the structure of wood that was produced after, as well as before, signs of stress, i.e., when decreases in height or diameter growth were visible. In the data set comprising previously published and new measurements, P50, i.e., the pressure potential necessary to induce a 50% loss in hydraulic conductivity, was negatively related to wood density. Declining trees produced wider annual rings with lower density than vigorous trees before their radial and height increment started to decline in 2003 or 2006. Trees that produced low-density wood under favorable water availability were more stressed by a sudden drought event because of higher P50 values in their sapwood. Due to the strong genotypic relationship between wood density and growth, we suggest that spruce trees selected for fast growth might experience limited hydraulic performance under the impact of extreme heat waves.

Wood density of Norway spruce in uneven-aged stands

2014 ◽  
Vol 44 (2) ◽  
pp. 136-144 ◽  
Author(s):  
Riikka Piispanen ◽  
Jaakko Heinonen ◽  
Sauli Valkonen ◽  
Harri Mäkinen ◽  
Sven-Olof Lundqvist ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Wood Density ◽  
Annual Ring ◽  
Ring Width ◽  
Mixed Linear Model ◽  
Data Set ◽  
Cambial Age ◽  
Canopy Position ◽  
Single Tree Selection ◽  
Spruce Stands

This study focused on wood density and annual ring width in Norway spruce (Picea abies (L.) Karst.) grown in uneven-aged stands (UAS). In total, 96 trees were harvested from five UAS that had been managed by single-tree selection for decades. A data set of 27 trees from even-aged stands (EAS) was used for comparison. In the UAS trees, high density and narrow annual rings were found in the juvenile wood near the pith. Thereafter, wood density rapidly decreased until the 20th annual ring, followed by an increase toward the bark. In the outermost rings, wood density again slightly decreased. The trends in wood density in the UAS trees correspond with those reported for naturally regenerated, even-aged Norway spruce stands, with the exception of the decrease in the outermost rings. A mixed linear model with ring width, cambial age, and canopy position as fixed parameters accounted for 53% of the variation in wood density of the UAS trees. In contrast to UAS trees, EAS trees showed increased wood density in the outer rings as a result of decreasing growth rate. The abrupt change in wood density of UAS trees may affect the properties of timber sawn close to the pith.

Age trends in genetic parameters of wood density in young Norway spruce

1999 ◽  
Vol 29 (1) ◽  
pp. 135-143 ◽  
Author(s):  
Gro Hylen
Keyword(s):  
Norway Spruce ◽  
Wood Density ◽  
Additive Genetic Variance ◽  
Genetic Correlations ◽  
Steady Increase ◽  
Environmental Variance ◽  
Cambial Age ◽  
Latewood Density ◽  
Age Trends ◽  
Heritability Estimates

Age trends of phenotypic, environmental, and additive genetic variance and heritability were estimated for overall density and its components earlywood and latewood densities and latewood proportion. The objective was to acquire information for both individual and cumulated rings from ring number 3 to 12 counted from the pith. Age-age correlations were calculated for cumulated density traits only. The wood density data were obtained with X-ray analysis of increment cores from 47 open-pollinated families of Norway spruce (Picea abies (L.) Karst.). The families had earlywood and latewood with significant differences in density for individual and cumulated rings and consequently for overall density. The latewood proportion had significant family variation for cumulated rings but not for all individual rings. Large fluctuations in environmental variance caused fluctuations in heritability estimates for successive rings. A strong decrease in environmental variance for all cumulated traits, especially from ring 3 to 5, resulted in a steady increase in heritability estimates. The latewood density had the highest heritability estimates and latewood proportion the lowest for both individual and cumulated rings. Overall density and the cumulated components at cambial age 12 showed strong genetic correlations with their respective traits at all younger ages.

AWARENESS AS AN ADAPTATION STRATEGY FOR REDUCING MORTALITY FROM HEAT WAVES: EVIDENCE FROM A DISASTER RISK MANAGEMENT PROGRAM IN INDIA

2012 ◽  
Vol 03 (02) ◽  
pp. 1250010 ◽  
Author(s):  
SAUDAMINI DAS ◽  
STEPHEN C. SMITH
Keyword(s):  
Risk Management ◽  
Heat Wave ◽  
Program Effectiveness ◽  
Heat Waves ◽  
Heat Stroke ◽  
Disaster Risk ◽  
Disaster Risk Management ◽  
Data Set ◽  
Awareness Campaigns ◽  
The Impact

Heat waves, defined as an interval of abnormally hot and humid weather, have become a prominent killer in recent years. With heat waves worsening with climate change, adaptation is essential; one strategy has been to issue heat wave warnings and undertake awareness campaigns to bring about behavioral changes to reduce heat stroke. Since 2002, the Indian state of Odisha has been undertaking a grassroots awareness campaign on "dos and don'ts" during heat wave conditions through the disaster risk management (DRM) program. The selection criteria for DRM districts were earthquake, flood and cyclone incidence; but subsequently, heat wave awareness also received intensive attention in these districts. We present quasi-experimental evidence on the impact of the program, taking DRM districts and periods as treatment units and the rest as controls, analyzing the impact on the death toll from heat stroke for the 1998 to 2010 period, using difference-in-difference (DID) regressions with a district level panel data set and a set of control variables. We find indications of program effectiveness with initial DID specifications, but results are not always robust. We then take into account a statewide heat wave advertising program, to which the poor have limited exposure but which may also provide spillover benefits, using a triple differencing approach; results suggest the heat wave awareness programs may have complementary impacts. We examine research strategies for further improvement in the precision of impact evaluation results for innovative programs of this type.

Effect of ring width, cambial age, and climatic variables on the within-ring wood density profile of Norway spruce Picea abies (L.) Karst.

Trees ◽  
2013 ◽  
Vol 27 (4) ◽  
pp. 913-925 ◽  
Author(s):  
Tony Franceschini ◽  
Fleur Longuetaud ◽  
Jean-Daniel Bontemps ◽  
Olivier Bouriaud ◽  
Benoît-Damien Caritey ◽  
...  
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Wood Density ◽  
Density Profile ◽  
Ring Width ◽  
Climatic Variables ◽  
Cambial Age

scholarly journals Wood density as a proxy for vulnerability to cavitation: Size matters

2017 ◽  
Vol 4 ◽  
pp. e001 ◽  
Author(s):  
Sabine Rosner
Keyword(s):  
Norway Spruce ◽  
Wood Density ◽  
Quadratic Regression ◽  
Ecological Studies ◽  
Standard Size ◽  
Density Measurements ◽  
Moisture Contents ◽  
Vulnerability To Cavitation ◽  
Cambial Age ◽  
Dry Wood

In this study, vulnerability to cavitation, P50 (i.e. the water potential causing 50 % loss of hydraulic conductivity), of Norway spruce trunkwood at different cambial age was related to wood density. Wood density was calculated from mass in the oven dry state related either to volume at the oven-dry state (dry wood density) or to volume at full saturation (basic wood density). Dry wood density and basic wood density were strongly linearly related (r² = 0.99); there was however a shift from the 1:1 reference line with increasing dry wood density. Dry wood density as well as basic wood density had similar high predictive qualities for P50 (r² = 0.85). The quadratic regression lines took however a quite different course below -4 MPa because volume shrinkage increased with increasing dry wood density. For Norway spruce sapwood with high dry wood density, mixing up different wood density traits would thus result in a predicted overestimation or underestimation of vulnerability to cavitation. Gravimetrically wood density measurements at different moisture contents (starting at full saturation) are easily to achieve on standard size specimens and the conversion curves obtained will be of high value for future ecological studies on other species and across species.

Predicting selected wood properties of jack pine following commercial thinning

2008 ◽  
Vol 38 (7) ◽  
pp. 2030-2043 ◽  
Author(s):  
Robert Schneider ◽  
S. Y. Zhang ◽  
D. Edwin Swift ◽  
Jean Bégin ◽  
Jean-Martin Lussier
Keyword(s):  
Wood Density ◽  
Ring Width ◽  
Wood Properties ◽  
Jack Pine ◽  
Modulus Of Rupture ◽  
Mixed Effect ◽  
Ring Density ◽  
Commercial Thinning ◽  
Cambial Age ◽  
The Impact

This paper examined the impact of commercial thinning on selected wood properties of jack pine ( Pinus banksiana Lamb.). Wood properties evaluated include wood density (ring density, earlywood ring density, and latewood ring density), percentage of latewood in the ring, and wood bending properties. Nonlinear, mixed-effect models have been developed using data from three commercially thinned sites in eastern Canada. Ring density followed the same pattern as percentage of latewood, in which cambial age, relative height, and ring width were found to have important effects. Earlywood and latewood ring densities changed within the juvenile wood zone until a plateau was reached. Ring width affected earlywood and latewood ring densities mainly in narrow rings. Wood bending stiffness (measured by modulus of elasticity) and strength (measured by modulus of rupture) increased with cambial age and wood density; whereas, wood strength was also affected by ring width. Commercial thinning did not influence the developed models, but it had an indirect effect through increased ring width.

scholarly journals VISUALISATION OF DEPENDENCIES BETWEEN CITY STRUCTURE AND THERMAL BEHAVIOUR IN BRNO

2016 ◽  
Vol XLI-B2 ◽  
pp. 741-745
Author(s):  
J. Novotny ◽  
M. Pivovarnik ◽  
S. J. Khalsa ◽  
F. Zemek
Keyword(s):  
Thermal Behaviour ◽  
Local Governments ◽  
Laser Scanning ◽  
Heat Waves ◽  
Hyperspectral Data ◽  
Strategic Decision ◽  
Data Set ◽  
City Structure ◽  
The Impact ◽  
The City

Good understanding of a city’s thermal regime and its dependency on the structure of the city provides key knowledge serving as an input for long-term strategic decision-making by local governments. The urban heat island, and more specifically overheating of the streets and adjacent buildings during summer heat waves, has been pointed out as an important issue in the city of Brno, Czech Republic. A complex research effort using remote sensing techniques has started which will analyse the impact of city structure on the thermal behaviour, principally the role of vegetation in the thermal regulation of streets. Two airborne data sets were acquired: hyperspectral data using CASI, SASI and TASI sensors (ITRES, Canada) and lidar mapping using a Riegl 680i instrument (RIEGL, Austria). The thermal data were acquired on two occasions: 7 February 2015 (winter season) and 4 July 2015 (summer season). A laser scanning data-set was acquired on 22 September 2015 with a point cloud density of approximately 15 points/m<sup>2</sup>. Surface temperature was retrieved from the thermal hyperspectral data by applying a temperature-emissivity separation algorithm. The 3-D structure of the city was classified from the laser scanning data; we distinguished three main classes: bare land, buildings and vegetation. In the paper we present figures comparing thermal behaviour with other features collected along linear transects through the central part of the city.

scholarly journals VISUALISATION OF DEPENDENCIES BETWEEN CITY STRUCTURE AND THERMAL BEHAVIOUR IN BRNO

2016 ◽  
Vol XLI-B2 ◽  
pp. 741-745
Author(s):  
J. Novotny ◽  
M. Pivovarnik ◽  
S. J. Khalsa ◽  
F. Zemek
Keyword(s):  
Thermal Behaviour ◽  
Local Governments ◽  
Laser Scanning ◽  
Heat Waves ◽  
Hyperspectral Data ◽  
Strategic Decision ◽  
Data Set ◽  
City Structure ◽  
The Impact ◽  
The City

Good understanding of a city’s thermal regime and its dependency on the structure of the city provides key knowledge serving as an input for long-term strategic decision-making by local governments. The urban heat island, and more specifically overheating of the streets and adjacent buildings during summer heat waves, has been pointed out as an important issue in the city of Brno, Czech Republic. A complex research effort using remote sensing techniques has started which will analyse the impact of city structure on the thermal behaviour, principally the role of vegetation in the thermal regulation of streets. Two airborne data sets were acquired: hyperspectral data using CASI, SASI and TASI sensors (ITRES, Canada) and lidar mapping using a Riegl 680i instrument (RIEGL, Austria). The thermal data were acquired on two occasions: 7 February 2015 (winter season) and 4 July 2015 (summer season). A laser scanning data-set was acquired on 22 September 2015 with a point cloud density of approximately 15 points/m&lt;sup&gt;2&lt;/sup&gt;. Surface temperature was retrieved from the thermal hyperspectral data by applying a temperature-emissivity separation algorithm. The 3-D structure of the city was classified from the laser scanning data; we distinguished three main classes: bare land, buildings and vegetation. In the paper we present figures comparing thermal behaviour with other features collected along linear transects through the central part of the city.

Age at Exposure to Parental Suicide and the Subsequent Risk of Suicide in Young People

Crisis ◽  
2018 ◽  
Vol 39 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Kuan-Ying Lee ◽  
Chung-Yi Li ◽  
Kun-Chia Chang ◽  
Tsung-Hsueh Lu ◽  
Ying-Yeh Chen
Keyword(s):  
Young People ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Model ◽  
Birth Registry ◽  
Data Set ◽  
Parental Suicide ◽  
The Impact ◽  
Age At Exposure

Abstract. Background: We investigated the age at exposure to parental suicide and the risk of subsequent suicide completion in young people. The impact of parental and offspring sex was also examined. Method: Using a cohort study design, we linked Taiwan's Birth Registry (1978–1997) with Taiwan's Death Registry (1985–2009) and identified 40,249 children who had experienced maternal suicide (n = 14,431), paternal suicide (n = 26,887), or the suicide of both parents (n = 281). Each exposed child was matched to 10 children of the same sex and birth year whose parents were still alive. This yielded a total of 398,081 children for our non-exposed cohort. A Cox proportional hazards model was used to compare the suicide risk of the exposed and non-exposed groups. Results: Compared with the non-exposed group, offspring who were exposed to parental suicide were 3.91 times (95% confidence interval [CI] = 3.10–4.92 more likely to die by suicide after adjusting for baseline characteristics. The risk of suicide seemed to be lower in older male offspring (HR = 3.94, 95% CI = 2.57–6.06), but higher in older female offspring (HR = 5.30, 95% CI = 3.05–9.22). Stratified analyses based on parental sex revealed similar patterns as the combined analysis. Limitations: As only register-­based data were used, we were not able to explore the impact of variables not contained in the data set, such as the role of mental illness. Conclusion: Our findings suggest a prominent elevation in the risk of suicide among offspring who lost their parents to suicide. The risk elevation differed according to the sex of the afflicted offspring as well as to their age at exposure.

State Medical Boards' Perceptions of a Minimum Data Set and Current Practices for Collecting Physician Information

2013 ◽  
Vol 99 (4) ◽  
pp. 40-45 ◽  
Author(s):  
Aaron Young ◽  
Philip Davignon ◽  
Margaret B. Hansen ◽  
Mark A. Eggen
Keyword(s):  
Media Coverage ◽  
The United States ◽  
Minimum Data Set ◽  
Direct Patient Care ◽  
Physician Workforce ◽  
Data Set ◽  
Minimum Data ◽  
State Medical Boards ◽  
The Impact ◽  
Current Practices

ABSTRACT Recent media coverage has focused on the supply of physicians in the United States, especially with the impact of a growing physician shortage and the Affordable Care Act. State medical boards and other entities maintain data on physician licensure and discipline, as well as some biographical data describing their physician populations. However, there are gaps of workforce information in these sources. The Federation of State Medical Boards' (FSMB) Census of Licensed Physicians and the AMA Masterfile, for example, offer valuable information, but they provide a limited picture of the physician workforce. Furthermore, they are unable to shed light on some of the nuances in physician availability, such as how much time physicians spend providing direct patient care. In response to these gaps, policymakers and regulators have in recent years discussed the creation of a physician minimum data set (MDS), which would be gathered periodically and would provide key physician workforce information. While proponents of an MDS believe it would provide benefits to a variety of stakeholders, an effort has not been attempted to determine whether state medical boards think it is important to collect physician workforce data and if they currently collect workforce information from licensed physicians. To learn more, the FSMB sent surveys to the executive directors at state medical boards to determine their perceptions of collecting workforce data and current practices regarding their collection of such data. The purpose of this article is to convey results from this effort. Survey findings indicate that the vast majority of boards view physician workforce information as valuable in the determination of health care needs within their state, and that various boards are already collecting some data elements. Analysis of the data confirms the potential benefits of a physician minimum data set (MDS) and why state medical boards are in a unique position to collect MDS information from physicians.

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