Wood For Trees Research Articles

Dynamic region growing approach for leaf-wood separation of individual trees based on geometric features and growing patterns

ABSTRACT The separation of leaf and wood points remains challenging due to the diversity of tree species and structures. We propose an automatic leaf-wood separation method from tree point clouds, leveraging trees’ shape information, growing patterns, and topological information for higher separation accuracy. First, the tree point clouds are roughly classified into initial planar, linear, and scattered points based on the dimensional structure of each point. Then, a slicing strategy combined with the DBSCAN (density-based spatial clustering of application with noise) clustering algorithm is used to exploit the potential wood clusters in each layer. A novel dynamic region growing algorithm based on an energy function is proposed for extracting tree trunk and large branches from initial planar points, incorporating the geometric features and growing patterns of trees. Finally, a novel inner-to-outer region growing method is proposed to extract the tiny branches based on voxel density and the principal direction. Twelve tree samples covering twelve species and locating tropical, temperate, and boreal areas are used to evaluate the method’s performance. The mean separation accuracy and kappa coefficient of the proposed method are 0.942 and 0.805, respectively. Experimental results indicate that the proposed method exhibits a strong ability to distinguish the wood and leaf points for various trees with different species and structures.

Not seeing the wood for the (invasive) trees: Visitors’ perceptions of invasive wilding conifers in the New Zealand landscape

Currently we know little about how visitors perceive invasive species, nor how this may vary across visitor cohorts. Previous research suggests that visitors to natural areas have a low awareness of the impact of invasive species. This note reports on a survey of domestic and international visitors (n = 231) in New Zealand, investigating their awareness of invasive wild conifers and attitudes toward their control. Awareness of the wild conifer problem was generally low, especially among international visitors. There were significant differences between domestic and international visitors, and among visitors of different nationalities for how wild conifers were perceived. International visitors, and particularly those from China or other Asian countries were more accepting of wild conifers in the landscape and less supportive of eradication. The findings have implications for management of invasive species, which requires the support of all stakeholders, including tourists, recreationists and their associated sectors.

Separation of Wood and Foliage for Trees From Ground Point Clouds Using a Novel Least-Cost Path Model

Nowadays, laser scanning technology has provided an effective andnondestructive approach to reveal the forest's developmental process and physiological properties. For the purpose of obtaining the 3-D spatial structure and skeleton of trees, this article addresses the separation of wood and foliage from the forest using two phases. The first global phase develops a pointwise supervised learning framework to classify forest point clouds. In order to improve the classification accuracy, we design new features for the learning process, which supplements the current geometric features in terms of the topological information. The second local phase designs a new least-cost path model to further separate wood and foliage points. The separation of branch points is formulated as an energy function and optimized by the dynamic programming technique. Experiments on different plots show that points from stems and branches are detected as wood points completely and correctly. The achieved average completeness, correctness, and F <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> score of the wood and foliage separation are 91.25%, 90.34%, and 0.91, respectively, which is promising to the phenotyping study related to the organism's physical form and structure.

Acoustic and physico-mechanical properties of spruce timber: influence of differently intensive pruning

The work studies the physico-mechanical properties of wood from the stands of Norway spruce (Picea abies (L.) Karst.), formed after pruning of various intensity. It was revealed that the high-intensity pruning in 23-year aged spruce stands (5-6 upper live branch clusters were left) led to a significant increase in the density of wood (by 15.6%) for trees with diameter larger than average in 3 years after. The removal of live and dry branches of lesser intensity does not affect the density of the wood. The wood formed as a result of 60 years of cultivation after pruning has quite high physical and mechanical properties: the compressive strength along the fibers is 51.6 ± 1.02 MPa compared to reference value of 44.5 MPa; and the larger impact toughness (0.68 ± 0.045 kgfm/cm2) than the reference value (0.40). It has been established that wood formed over 60-year cultivation after pruning has resonant properties: the average acoustic constant is 11.4 m4/kg × sec., while the optimal value of this indicator for the use of this wood in the music industry is more than 12 m4/kg × sec. It has been concluded that pruning combined with rational stand density makes it possible to produce wood with acoustic properties.

On the importance of detailed structure in molecular electronics (and why microscopic models cannot see the wood for trees)

ABSTRACTWe study the charge transport properties of a system of liquid crystal discotic molecules in two distinct phases. To differentiate between the two phases, we use a self-consistent model that describes the pairwise interaction between molecules, the electronic coupling between them and the difference in orbital energies. This multi-scale approach hinges upon having systems that are both accurate (to within atomic resolution) and large (10,000 molecules). The two phases have dramatically different charge transport network topologies, directly correlated to their molecular structures. We quantify the charge transport on both a macroscopic and microscopic scale, taking advantage of the model’s resolution to understand the role of molecular packing in charge transport.

Carbon Value Analysis of Batang Gadis National Park, Mandailing Natal Regency, North Sumatera Province, Indonesia

Global warming is an important issue in the world which it gives a negative effect on human life. One indicator of global warming is increasing greenhouse gas i.e. carbondioxide from human activities. Deforestation and forest degradation are the second largest contributor of carbon into the atmosphere, after the use of fossil fuels by industry and transportation. As lungs of the world, forest is enable to produce renewable energy sources i.e. biomass. Forest carbon stock in above ground biomass (AGB) is the greatest effect source on deforestation and forest degradation. Therefore, it is necessary to perform a study the potential of carbon in forest. The purpose of this research is to determine carbon stock value in Batang Gadis National Park, Mandailing Natal Regency, North Sumatera Province, Indonesia. The carbon potential stored in this forest vegetation is calculated using AGB allometric equation by using data in diameter at breast height (dbh = 1.3 m), height, and density of the wood for trees. Data obtained from secondary data is Asset Assessment Report which State Controlled Forest Natural Resources Batang Gadis National Park, 2016. Study locations were Pagar Gunung and Sopo Tinjak Villages. Carbon stock values were calculated and analyzed with assumption that a half of biomass part is carbon stock which using Australian carbon price about AUD $ 11.82 Australia (Australian dollars) and EU € 5 (US $ 6). The results showed that the total biomass in Pagar Gunung and Sopo Tinjak Villages amounted to 259.83 tonnes and 160.89 tonnes. From the results of the total biomass, the total carbon stocks (C) and CO2 stocks in both villages are 210.36 tonnes (129.92 tonnes in Pagar Gunung Village and 80.45 tonnes in Sopo Tinjak Village) and 772.03 tonnes (476.79 tonnes in Pagar Gunung Village and 295.24 tonnes in Sopo Tinjak Village). By using the carbon price prevailing in the market place Australia Emission Trading System (ETS) and the EU ETS (AUD $ 11.82/t CO2e and € 5 (US $ 6)/t CO2e), the value of carbon stock that can be produced from Batang Gadis National Park (Pagar Gunung and Sopo Tinjak Villages) is about Rp. 92,499,921.72 (in AUD $) or Rp. 61,654,433.67 (in US $).

Missing the Wood for the Wrong Trees: On the Difficulty of Defining the Complexity of Complex Problem Solving Scenarios.

In this paper we discuss how the lack of a common framework in Complex Problem Solving (CPS) creates a major hindrance to a productive integration of findings and insights gained in its 40+-year history of research. We propose a framework that anchors complexity within the tri-dimensional variable space of Person, Task and Situation. Complexity is determined by the number of information cues that need to be processed in parallel. What constitutes an information cue is dependent on the kind of task, the system or CPS scenario used and the task environment (i.e., situation) in which the task is performed. Difficulty is conceptualised as a person’s subjective reflection of complexity. Using an existing data set of N = 294 university students’ problem solving performances, we test the assumption derived from this framework that particular system features such as numbers of variables (NoV) or numbers of relationships (NoR) are inappropriate indicators of complexity. We do so by contrasting control performance across four systems that differ in these attributes. Results suggest that for controlling systems (task) with semantically neutral embedment (situation), the maximum number of dependencies any of the output variables has is a promising indicator of this task’s complexity.

Disposables vs Reusables: Are we Missing the Wood for the Trees?

Disposables vs Reusables: Are we Missing the Wood for the Trees?

Genetics: HotNet2-see the wood for the trees.

Genetics: HotNet2-see the wood for the trees.

不同林分起源的相容性生物量模型构建

Biomass equations for individual-trees have appeared frequently in the ecological and forestry literature over the last 60 years as biomass estimation is a prerequisite for studies on forest productivity,nutrient cycling and for calculating carbon sequestration,storage and other structural and functional attributes of forest ecosystems. Over the same period of time,the methods of developing biomass equations for total tree and component biomass have evolved from single equation least squares to multivariate adjustment in proportion and simultaneous equations,both linear and nonlinear. The single equation approach relates total tree biomass and its components such as stem,wood,bark,branches,and foliage to predictor variables such as diameter at breast height,height and sometime also crown width using log transformed data through least squares regression. The equation for each component is estimated separately without taking into account( 1) the inherent correlation among the biomass components measured on the same sample trees and( 2) the logical constraint between the sum of predicted biomass for tree components and the prediction for the total tree. As a result,biomass equations developed through this approach fall short of statistical efficiency in parameter estimation and lack compatibility among the component equations( Parresol 1999). The lack of compatibility means inconsistency in logic in the sense that the predicted values from summing the biomass equations of tree components do not equal to the predicted value from theequation for the total tree biomass. Development of compatible individual-tree biomass models were well reported in the literature,while how to construct these biomass models for trees from different stand origin has not been investigated so far. In this paper,generalized models on total above-ground biomass and its four components( stem wood,stem bark,branch, and foliage) for trees from different stand origin were established using the methods of adjustment in proportion and nonlinear simultaneous equations. Totally 150 Masson pine( Pinus masson iana) trees were sampled for biomass investigation in southern China. For the two approaches mentioned above,i. e. adjustment in proportion and nonlinear simultaneous equations,controlling jointly from level to level by ratio functions and controlling directly under total biomass by proportion functions were employed. Covariate variables of one-,two- and three-variable biomass models were obtained from five stand variable candidates of diameter at breast height,tree total height,diameter at ground level,height to crown base and crown width. Weighted least square regression was used to remove the heteroscedasticity of biomass models. The results showed that both methods of adjustment in proportion and nonlinear simultaneous equations could efficiently ensure that the total biomass is equal to the summary of its components with high prediction accuracy. However,the prediction accuracy of nonlinear simultaneous equations was generally much higher than that of adjustment in proportion. The approach of controlling directly by proportion functions was slightly better than the one controlling jointly by ratio functions. The function of each component biomass itself as weighted function could remove heteroscedasticity effectively. The biomass models for each component with three variables( diameter at breast height,height and crown width) had the highest prediction accuracy,following by the two variables( diameter at breast height and height),and the single variable( diameter at breast height) model. The discrepancies among the models were very small,however. For balancing the model prediction accuracy and survey cost in constructing biomass model for trees from different stand origin,we suggest adapting the nonlinear simultaneous equations of controlling directly under total biomass with diameter at breast height and height as covariables.

K. Arthurson: Social mix and the city. Challenging the mixed communities consensus in housing and urban planning policies

The number of publications on social mix and housing and city planning are adding up to an insurmountable quantity. Nevertheless, the issue stays hot, that is the least one can say. All over the world governments still try to solve social problems by mixing populations. Major journals and edited volumes (see e.g. Bridge et al. 2012) recently took stock of the policies and the debates and contested used methods and evaluated policies goals and results. So what do we need more? Indeed, a book that shows us the wood for trees. And that is exactly what Kathy Arthurson, who wrote already extensively on the issue, did with her small book ‘Social Mix and the city. Challenging the mixed communities consensus in housing and urban planning policies’. With the book she also updated the widely quoted seminal article of another Australian scholar, Wendy Sarkissian (1976). The central question Arthurson wants to tackle is how to interpret the recent reviewed enthusiasm for social mix policies in late 20th and early 21st century Australia. She seeks to enhance the current understanding of the political and intellectual agenda’s for social mix by considering its comparative and historical context and the purpose for which it is used. It is critical to unravel these different conceptualizations and uses because policies can be driven by different agendas, and if the underlying beliefs and assumptions are not placed in their historical context, we may be doomed to repeat past errors (p. 3). Arthurson proceeds in 2 parts and 9 chapters. In the first part, from chapter 2 to 5, Arthurson sets out the historical context of social mix. In chapter 2 she traces the origins of the concept of social mix back to town planning in Britain from the mid-19th century and touches its later implementation in the US. Fundamental questions that are addressed include: what are the historical foundations of the idea of social mix, what problems was it initially constructed to address and who constructed these problems? (p. 6). In chapter 3 Arthurson explores the growth in support for social mix policies and the ways in which they were conceptualized in the era after World War 2 (period 1950–1970). In particular this chapter focusses on the Australian case, including the criticisms and questioning of the value of the concept at that stage.

Can't see the wood for the trees? Using statistical frameworks to draw the bigger picture

This paper argues that in many areas of official statistics, the accessibility (‘understandability’) of the results can be improved substantially by the presentation of the statistics according to an appropriate presentational/analytical framework which is itself part of a wider suite of frameworks (conceptual, statistical, quality etc). This approach can help to align sources and results; to clarify underlying processes and interrelationships; and to demonstrate how particular statistical series or indicators relate to the ‘bigger picture’. The paper outlines some examples of different types of presentational frameworks – supply/demand, process; and cause and effect – including the labour market, migration, and criminal justice. It highlights some of the benefits of this approach in relation to making the underlying information in the statistics more valuable – for example, more accessible (and hence more trustworthy) to users. It concludes that international experience in the development and use of statistical frameworks might usefully be reviewed as an aid to international statistical comparability.

Wood for the Trees

Wood for the Trees

Allometric equations for young northern hardwoods: the importance of age-specific equations for estimating aboveground biomass

Estimates of aboveground biomass and nutrient stocks are commonly derived using equations that describe tree dimensional relationships. Despite the widespread use of this approach, there is little information about whether equations specific to stand age are necessary for accurate biomass predictions. We developed equations for small trees (2–12 cm diameter) of six species in four young northern hardwood stands. We then compared our equations with equations used frequently in the literature that were developed in mature stands (Whittaker et al. 1974. Ecol. Monogr. 44: 233–252). Our equations for yellow birch ( Betula alleghaniensis Britt.) predicted 11%–120% greater stem wood for individual trees compared with the equations from Whittaker et al. and, on average, 50% greater aboveground yellow birch biomass in the four stands that we studied. Differences were less pronounced for sugar maple ( Acer saccharum Marsh.) and American beech ( Fagus grandifolia Ehrh.); our equations predicted, on average, 9% greater aboveground stand biomass for sugar maple and 3% lower biomass for American beech compared with Whittaker et al. Our results suggest that stand age may be an important factor influencing the aboveground allometry and biomass of small yellow birch trees in these developing northern hardwood stands.

Carbon accumulation along a stand development sequence of Nothofagus antarctica forests across a gradient in site quality in Southern Patagonia

Above- and below-ground C pools were measured in pure even-aged stands of Nothofagus antarctica (Forster f.) Oersted at different ages (5–220 years), crown and site classes in the Patagonian region. Mean tissue C concentration varied from 46.3% in medium sized roots of dominant trees to 56.1% in rotten wood for trees grown in low quality sites. Total C concentration was in the order of: heartwood > rotten wood > sapwood > bark > small branches > coarse roots > leaves > medium roots > fine roots. Sigmoid functions were fitted for total C accumulation and C root/shoot ratio of individual trees against age. Total C accumulated by mature dominant trees was six times greater than suppressed trees in the same stands, and total C accumulated by mature dominant trees grown on the best site quality was doubled that of those on the lowest site quality. Crown classes and site quality also affected the moment of maximum C accumulation, e.g. dominant trees growing on the worse site quality sequestered 0.73 kg C tree −1 year −1 at 139 years compared to the best site where 1.44 kg C tree −1 year −1 at 116 years was sequestered. C root/shoot ratio decreased over time from a maximum value of 1.3–2.2 at 5 years to a steady-state asymptote of 0.3–0.7 beyond 60 years of age depending on site quality. Thus, root C accumulation was greater during the regeneration phase and for trees growing on the poorest sites. The equations developed for individual trees have been used to estimate stand C accumulation from forest inventory data. Total stand C content ranged from 128.0 to 350.9 Mg C ha −1, where the soil C pool represented 52–73% of total ecosystem C depending on age and site quality. Proposed equations can be used for practical purposes such as estimating the impact of silvicultural practices (e.g. thinning or silvopastoral systems) on forest C storage or evaluating the development of both above- and below-ground C over the forest life cycle for different site qualities for accurate quantification of C pools at regional scale.

Seeing the Wood for the Trees

Seeing the Wood for the Trees

Seeing the wood for the trees

Seeing the wood for the trees

Not seeing the wood for the imaginary trees. Or, who’s messing with our article?

Ambler (in this issue) has been very quick to comment on our recent paper in this journal (Nairn & Fine, IJA, 27(3), 2008) in which we discuss the implications of recent findings from the cognitive sciences for the ethics of advertising to children. We welcome this opportunity to address some of the many misunderstandings, misattributions and misplaced criticisms that constitute Ambler’s commentary, as well as to re-emphasise and expand on some of the important points from our paper. First, we briefly review the line of argument of our original paper. Those who have read Ambler’s response need fear no boredom through repetition, as our thesis bears little resemblance to the version of it provided by Ambler. Next, we address the seven issues characterised by Ambler as ‘contentious’, a description that turns out to depend on fundamental mischaracterisations of our account. Finally, we reiterate the central conceptual and practical points of our paper. Discussion of the effects and ethics of marketing to children will continue to be incomplete so long as discussants fail to acknowledge, and address in the form of a mature debate, the role of implicit cognition in consumer psychology.

Seeing the wood for the trees

Seeing the wood for the trees

Missing the ethical wood for the bureaucratic trees

Missing the ethical wood for the bureaucratic trees