Changes in attitudes to solid timber species: a test of some promotional elements

1984 ◽  
Vol 14 (1) ◽  
pp. 22-26 ◽  
Author(s):  
R. J. Cooper ◽  
S. Kalafatis
Keyword(s):  
Analysis Of Variance ◽  
Individual Species ◽  
Timber Species ◽  
Multidimensional Model ◽  
Fishbein Model ◽  
Or Applications

The significance of two promotional elements (presentation and product) in explaining the variations in the attitudes towards timber species are examined in this paper. In measuring such attitudes, the original Fishbein model is used and the attitudes are expressed as a function of five pretested attributes (beauty, durability, smoothness of texture, coldness, and modernity). A detailed ANOVA showed that variations in attitudes were explained mainly by the type of product and to a lesser extent by the two-way interactions of product and the species used to produce the product while the type of presentation was not significant. It was found that the respondents had certain preconceived ideas about the properties of individual species and these ideas were directly related to products and (or) applications traditionally associated with each species. Finally, the multidimensional model of "utilities," UNICON was applied to the data. Two analyses were performed, one on the utilities of the different products, species, and types of presentation and one on the utilities of the different attributes tested. The findings corroborated those of the analysis of variance. Very different utility factors were attached to different combinations of products made out of different species while the type of presentation was not significant. Therefore, for promotional purposes a very detailed and segmented approach is needed and this will depend on the particular product and the species used and consequently different attributes must be emphasised and promoted.

Patterns in subtidal marine assemblages associated with a deep-water sewage outfall

1996 ◽  
Vol 47 (1) ◽  
pp. 1 ◽  
Author(s):  
DE Roberts
Keyword(s):  
Experimental Design ◽  
Analysis Of Variance ◽  
Deep Water ◽  
Spatial Scales ◽  
Individual Species ◽  
Spatial And Temporal Patterns ◽  
Macrobenthic Assemblages ◽  
Ocean Outfall ◽  
Control Interaction ◽  
Hard Substrata

The macrobenthic assemblages living on hard substrata in the vicinity of the Sydney deep-water ocean outfall at North Head were sampled from March 1991 to April 1994. The main objective of the study was to determine whether spatial and temporal patterns in macrobenthic diversity and abundance were affected by the outfall. The assemblages were sampled according to an experimental design that had three sites nested within each of three locations. These locations were North Head (outfall location), Long Reef and Bungan Head (control locations). Ten replicate quadrats at each site were photographed with a jump camera. These photographs were then sampled to provide estimates of the number and abundance of the major component phyla and also abundances of individual species. An asymmetrical analysis of variance detected a significant time × outfall versus control interaction for the total number of species, bryozoans and cnidarians and for the abundances of two bryozoan species and a silt matrix. Smaller-scale interactions among sites through time occurred for many taxa, representing both inherent 'noise' and some evidence for outfall effects at these smaller spatial scales. This study demonstrates that there is correlative evidence of an effect of the outfall, but in general the assemblages showed various spatial and temporal fluctuations that should not be attributed to sewage.

scholarly journals Comparing Individual Tree Height Information Derived from Field Surveys, LiDAR and UAV-DAP for High-Value Timber Species in Northern Japan

Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 223 ◽  
Author(s):  
Kyaw Moe ◽  
Toshiaki Owari ◽  
Naoyuki Furuya ◽  
Takuya Hiroshima
Keyword(s):  
Forest Management ◽  
Field Survey ◽  
Tree Height ◽  
Spatial Position ◽  
Individual Species ◽  
Lidar Data ◽  
Timber Species ◽  
Individual Tree ◽  
Broadleaf Species ◽  
Northern Japan

High-value timber species such as monarch birch (Betula maximowicziana Regel), castor aralia (Kalopanax septemlobus (Thunb.) Koidz), and Japanese oak (Quercus crispula Blume) play important ecological and economic roles in forest management in the cool temperate mixed forests in northern Japan. The accurate measurement of their tree height is necessary for both practical management and scientific reasons such as estimation of biomass and site index. In this study, we investigated the similarity of individual tree heights derived from conventional field survey, digital aerial photographs derived from unmanned aerial vehicle (UAV-DAP) data and light detection and ranging (LiDAR) data. We aimed to assess the applicability of UAV-DAP in obtaining individual tree height information for large-sized high-value broadleaf species. The spatial position, tree height, and diameter at breast height (DBH) were measured in the field for 178 trees of high-value broadleaf species. In addition, we manually derived individual tree height information from UAV-DAP and LiDAR data with the aid of spatial position data and high resolution orthophotographs. Tree heights from three different sources were cross-compared statistically through paired sample t-test, correlation coefficient, and height-diameter model. We found that UAV-DAP derived tree heights were highly correlated with LiDAR tree height and field measured tree height. The performance of individual tree height measurement using traditional field survey is likely to be influenced by individual species. Overall mean height difference between LiDAR and UAV-DAP derived tree height indicates that UAV-DAP could underestimate individual tree height for target high-value timber species. The height-diameter models revealed that tree height derived from LiDAR and UAV-DAP could be better explained by DBH with lower prediction errors than field measured tree height. We confirmed the applicability of UAV-DAP data for obtaining the individual tree height of large-size high-value broadleaf species with comparable accuracy to LiDAR and field survey. The result of this study will be useful for the species-specific forest management of economically high-value timber species.

scholarly journals Contribution of Vouacapoua americana fruit-fall to the release of biomass in a lowland Amazon forest

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Victor Juan Ulises Rodriguez Chuma ◽  
Darren Norris
Keyword(s):  
Single Species ◽  
Individual Species ◽  
Spatially Explicit ◽  
Timber Species ◽  
Amazon Forest ◽  
Ensemble Model ◽  
Population Declines ◽  
Detailed Understanding ◽  
Forest Strata ◽  
Rapid Transfer

AbstractFruit-fall provides the transfer of biomass and nutrients between forest strata and remains a poorly understood component of Amazon forest systems. Here we detail fruit-fall patterns including those of Vouacapoua americana a Critically Endangered timber species across 25 km2 of lowland Amazon forest in 2016. We use multi-model comparisons and an ensemble model to explain and interpolate fruit-fall data collected in 90 plots (totaling 4.42 ha). By comparing patterns in relation to observed and remotely sensed biomass estimates we establish the seasonal contribution of V. americana fruit-fall biomass. Overall fruit-fall biomass was 44.84 kg ha−1 month−1 from an average of 44.55 species per hectare, with V. americana dominating both the number and biomass of fallen fruits (43% and 64%, number and biomass respectively). Spatially explicit interpolations provided an estimate of 114 Mg dry biomass of V. americana fruit-fall across the 25 km2 area. This quantity represents the rapid transfer by a single species of between 0.01 and 0.02% of the overall above ground standing biomass in the area. These findings support calls for a more detailed understanding of the contribution of individual species to carbon and nutrient flows in tropical forest systems needed to evaluate the impacts of population declines predicted from short (< 65 year) logging cycles.

scholarly journals Hardwood Stumpage Price Trends and Regional Market Differences in Pennsylvania

2003 ◽  
Vol 20 (3) ◽  
pp. 124-130 ◽  
Author(s):  
Peter E. Linehan ◽  
Michael G. Jacobson ◽  
Marc E. McDill
Keyword(s):  
General Level ◽  
Individual Species ◽  
Timber Species ◽  
Northern Red Oak ◽  
White Oak ◽  
Yellow Poplar ◽  
White Ash ◽  
Stumpage Price ◽  
Price Growth ◽  
Species Groups

Abstract Pennsylvania is a major hardwood lumber producing state. Since 1984, the Pennsylvania Timber Market Report (TMR) has provided quarterly stumpage and mill-delivered prices for important timber species groups for four subregions within the state. Stumpage price data covering the period from 1984 to 2000 are available for eight species groups. These series were analyzed with log-linear regression to determine nominal and real price growth rates. While all species show increasing prices over the period, three distinct groups are identified. Black cherry and hard maple show the highest rates of price growth (10.1% to 14.1% nominal and 6.5% to 10.7% real); northern red oak, soft maple, and yellow-poplar form an intermediate group (6.6% to 9.5% nominal and 3.1% to 6.1% real); and white oak, white ash, and miscellaneous hardwoods show the lowest rates of growth (4.3% to 6.8% nominal and 0.0% to 3.6% real). Additionally, a regression model with qualitative regional variables (i.e., “dummy” variables) was used to test whether the four market regions used by the TMR are statistically different, in terms of both the general level of prices and rates of change. The results clearly show significant differences in the price levels and trends among all regions for at least some species groups. The two regions showing the fewest significant differences are the southeast and southwest regions. The two northern regions are quite different from the southern regions. The northwest region was the most distinct of all the regions. Specific regional differences are noted for individual species groups. North. J. Appl. For. 20(3):124–130.

Cognitive Algebra in Multi-Attribute Attitude Models

1975 ◽  
Vol 12 (2) ◽  
pp. 151-164 ◽  
Author(s):  
James R. Bettman ◽  
Noel Capon ◽  
Richard J. Lutz
Keyword(s):  
Analysis Of Variance ◽  
Individual Level ◽  
Level Data ◽  
Single Attribute ◽  
Fishbein Model

Research on multi-attribute attitude models has relied on correlational methods. An analysis of variance paradigm applied to individual level data supports the multiplicative assumption of multi-attribute models. A single-attribute form of the Fishbein model is found to be superior to a similar version of the “adequacy-importance” model.

scholarly journals Assessment of Chainsaw Milling Enterprise in Benue State, Nigeria

2019 ◽  
pp. 1-19
Author(s):  
L. N. Sambe
Keyword(s):  
Analysis Of Variance ◽  
Sampling Technique ◽  
The State ◽  
Variable Cost ◽  
Potential Contribution ◽  
Timber Species ◽  
Gross Margin ◽  
Indigenous Groups ◽  
Marketing Efficiency ◽  
Multistage Sampling

The paucity of information on chainsaw milling enterprise has contributed to poor planning and development of timber resources in Nigeria. This study has accessed the marketing efficiency and structure with a view of evaluating its potential contribution to the livelihoods and economic development of Benue State. Multistage sampling technique and purposeful sampling technique were applied to determine the study sample which was drawn from the three geopolitical zones in the State; Zone A, Zone B and Zone C. Applying a sampling intensity of 30%, seven (7) Local Government Areas (LGAs) were sampled from the 23 LGAs of the State for the study.  Based on this arrangement 79 chainsaw millers were selected and interviewed on the trading activities. Data were collected and analyzed using descriptive statistics such as percentages and frequency distribution. Also gross margin analysis, marketing margin, marketing efficiency, Analysis of variance, T-test Statistics, Index of market concentration (IMC), Rate of return on investment (RORI) and Gross Ratio (GR) were used in the determining the profitability and the efficiency of chainsaw millers trading efficiency in the study area.  The study revealed that the trade is male dominated having 100% of the respondents as males. Similarly, the indigenous groups dominated the chainsaw milling and with the Tiv having the majority of (65.8%), this was followed by the Idoma (13.7%), Igede, (12.5%) and Igbo (5.5%), Igala and Sura 1.4% each. The study identified 18 timber species that were marketed in the study area and that 2,411, 37,733, and 69,492 volumes were marketed in zones A, B and C respectively.  The result of the gross margin and market efficiency showed that that the chainsaw milling activities are profitable and efficient.  It revealed the mean monthly gross margin (GM) of 39,688.00, 128,730, and 84,000 with corresponding RORI of 84.19, 43.93, and 1.80 for the chainsaw millers. The Analysis of Variance (ANOVA) of GMs were significant with 0.013. The Total Revenue and Total Variable Cost (TVC) equally showed significance with 0.045, 0.000, 0.000. The IMC, Gini coefficient of 0.1891, 0.3218 and 0.1829, indicated that the concentration was low with income inequality but with a competitive market.

Comparative Morphology of Intercellular Bridges Between Developing Germ Cells of the Ovary

1970 ◽  
Vol 28 ◽  
pp. 328-329
Author(s):  
J. R. Ruby ◽  
R. F. Dyer ◽  
R. G. Skalko ◽  
R. F. Gasser ◽  
E. P. Volpe
Keyword(s):  
Germ Cells ◽  
Rana Pipiens ◽  
Comparative Morphology ◽  
Dense Material ◽  
Individual Species ◽  
Microscope Examination ◽  
Electron Dense Material ◽  
Intercellular Bridges ◽  
Cytoplasmic Side ◽  
Intercellular Connections

An electron microscope examination of fetal ovaries has revealed that developing germ cells are connected by intercellular bridges. In this investigation several species have been studied including human, mouse, chicken, and tadpole (Rana pipiens). These studies demonstrate that intercellular connections are similar in morphology regardless of the species.Basically, all bridges are characterized by a band of electron-dense material on the cytoplasmic side of the tri-laminar membrane surrounding the connection (Fig.l). This membrane is continuous with the plasma membrane of the conjoined cells. The dense material, however, never extends beyond the limits of the bridge. Variations in the configuration of intercellular connections were noted in all ovaries studied. However, the bridges in each individual species usually exhibits one structural characteristic seldom found in the others. For example, bridges in the human ovary very often have large blebs projecting from the lateral borders whereas the sides of the connections in the mouse gonad merely demonstrate a slight convexity.

Modelling ecosystem adaptation and dangerous rates of global warming

2019 ◽  
Vol 3 (2) ◽  
pp. 221-231 ◽  
Author(s):  
Rebecca Millington ◽  
Peter M. Cox ◽  
Jonathan R. Moore ◽  
Gabriel Yvon-Durocher
Keyword(s):  
Climate Change ◽  
Global Warming ◽  
Diffusion Rate ◽  
Individual Species ◽  
Genetic Evolution ◽  
Rates Of Change ◽  
Rapid Climate Change ◽  
Warming Climate ◽  
Intraspecies Competition ◽  
High Trait

Abstract We are in a period of relatively rapid climate change. This poses challenges for individual species and threatens the ecosystem services that humanity relies upon. Temperature is a key stressor. In a warming climate, individual organisms may be able to shift their thermal optima through phenotypic plasticity. However, such plasticity is unlikely to be sufficient over the coming centuries. Resilience to warming will also depend on how fast the distribution of traits that define a species can adapt through other methods, in particular through redistribution of the abundance of variants within the population and through genetic evolution. In this paper, we use a simple theoretical ‘trait diffusion’ model to explore how the resilience of a given species to climate change depends on the initial trait diversity (biodiversity), the trait diffusion rate (mutation rate), and the lifetime of the organism. We estimate theoretical dangerous rates of continuous global warming that would exceed the ability of a species to adapt through trait diffusion, and therefore lead to a collapse in the overall productivity of the species. As the rate of adaptation through intraspecies competition and genetic evolution decreases with species lifetime, we find critical rates of change that also depend fundamentally on lifetime. Dangerous rates of warming vary from 1°C per lifetime (at low trait diffusion rate) to 8°C per lifetime (at high trait diffusion rate). We conclude that rapid climate change is liable to favour short-lived organisms (e.g. microbes) rather than longer-lived organisms (e.g. trees).

Analysis of Variance and Covariance

2007 ◽  
Author(s):  
C. Patrick Doncaster ◽  
Andrew J. H. Davey
Keyword(s):  
Analysis Of Variance

Analysis of Variance Designs

2008 ◽  
Author(s):  
Glenn Gamst ◽  
Lawrence S. Meyers ◽  
A. J. Guarino
Keyword(s):  
Analysis Of Variance
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