scholarly journals Understanding the interactions between wind and trees: an introduction to the IUFRO 8th Wind and Trees Conference (2017)

2019 ◽  
Vol 92 (4) ◽  
pp. 375-380 ◽  
Author(s):  
Barry Gardiner ◽  
Alexis Achim ◽  
Bruce Nicoll ◽  
Jean-Claude Ruel
Keyword(s):  
Forest Management ◽  
Ecological Impact ◽  
Critical Factor ◽  
Statistical Modelling ◽  
Wind Damage ◽  
Wind Loading ◽  
Exact Nature ◽  
Soil System ◽  
Book Format ◽  
Risk Of Wind Damage

Abstract This paper discusses the advance in our understanding of the interaction between wind and trees over the last 25 years. It does this by comparing papers in this special issue of Forestry and a companion volume in Agricultural and Forest Meteorology, based on work presented at the 8th IUFRO Wind and Trees Conference in 2017, with papers published in book format after the 1st IUFRO Wind and Trees Conference in 1993. The analysis is divided into sections on ‘airflow and tree mechanics’, ‘forest management and ecology’, ‘tree adaptation and acclimation’ and ‘modelling and statistical techniques’. It is clear that in the last 25 years large advances have been made in our understanding of airflow and turbulence within and above forest canopies and the wind flow and wind loading around and on individual trees. There have also been important developments in the mechanistic and statistical modelling of wind damage risk to forests. Much of the progress has been aided by the enormous advances in measurement systems, computer power and modelling techniques. Furthermore, this knowledge is beginning to influence the approach to temperate and boreal forest management and the development of systems to mitigate the risk of wind damage. At the same time there has been a growing awareness of the ecological impact of wind in many forests around the world, including tropical forests. However, other areas of the effect of wind on trees have progressed much less in the last 25 years. This includes the process of fatiguing in the root-soil system, both during individual storms and over longer periods, and which is known to be a critical factor in the process of windthrow. In addition the exact nature of damage propagation within forests during a storm, and then in subsequent storms, has received relatively little attention although new studies using advanced computational methods are making advances. Of particular relevance, and despite the known critical importance of tree acclimation to the wind, there have been very few studies in the last 25 years on wind acclimation in full-size trees. This is an area of enormous importance in understanding how resistance to the wind varies for different species and between areas with different wind climates. In summary, overall much has been learnt since the 1st Wind and Trees conference but there remain many intriguing and exciting challenges ahead for this multi-disciplinary subject.

Life-style services and yield from south-Swedish forests adaptively managed against the risk of wind damage: a simulation study

2014 ◽  
Vol 15 (8) ◽  
pp. 1489-1500 ◽  
Author(s):  
Mikael Andersson ◽  
Seppo Kellomäki ◽  
Barry Gardiner ◽  
Kristina Blennow
Keyword(s):  
Simulation Study ◽  
Life Style ◽  
Wind Damage ◽  
Risk Of Wind Damage

Effect of forest management on the formation and stability of phytolith and PhytOC in forest ecosystem

2021 ◽  
Author(s):  
Lin Xu ◽  
Yongjun Shi ◽  
Wanjie Lv ◽  
Zhengwen Niu ◽  
Ning Yuan ◽  
...  
Keyword(s):  
Carbon Sequestration ◽  
Forest Management ◽  
Forest Ecosystem ◽  
Management Practices ◽  
Forest Ecosystems ◽  
Moso Bamboo ◽  
Soil System ◽  
Silicon Fertilization ◽  
Global Carbon

<p>Forest ecosystem has a high carbon sequestration capacity and plays a crucial role in maintaining global carbon balance and climate change. Phytolith-occluded carbon (PhytOC), a promising long-term biogeochemical carbon sequestration mechanism, has attracted more attentions in the global carbon cycle and the regulation of atmospheric CO<sub>2</sub>. Therefore, it is of practical significance to investigate the PhytOC accumulation in forest ecosystems. Previous studies have mostly focused on the estimation of the content and storage of PhytOC, while there were still few studies on how the management practices affect the PhytOC content. Here, this study focused on the effects of four management practices (compound fertilization, silicon fertilization, cut and control) on the increase of phytolith and PhytOC in Moso bamboo forests. We found that silicon fertilization had a greater potential to significantly promote the capacity of carbon sequestration in Moso bamboo forests. this finding positively corresponds recent studies that the application of silicon fertilizers (e.g., biochar) increase the Si uptake<strong><sup>1</sup></strong> to promote phytolith accumulation and its PhytOC sequestration in the plant-soil system<strong><sup>2</sup></strong>. Of course, the above-mentioned document<strong><sup>2</sup></strong> also had their own shortcomings, i.e., the experimental research time was not long, lacking long-term follow-up trial and the bamboo forest parts were also limited, so that the test results lack certain reliability. We have set up a long-term experiment plot to study the effects of silicon fertilizer on the formation and stability of phytolith and PhytOC in Moso bamboo forests. But anyway, different forest management practices, especially the application of high-efficiency silicon-rich fertilizers<strong><sup>1</sup></strong>, may be an effective way to increase the phytolith and PhytOC storage in forest ecosystems, and thereby improve the long-term CO<sub>2 </sub>sequestration capacity of forest ecosystems. Research in this study provides a good "forest plan" to achieve their national voluntary emission reduction commitments and achieves carbon neutrality goals for all over the world.</p><p>Refences:</p><p><sup>1</sup>Li et al., 2019. Plant and soil, 438(1-2), pp.187-203.</p><p><sup>2</sup>Huang et al., 2020, Science of The Total Environment, 715, p.136846.</p>

scholarly journals Does Variable-Density Thinning Increase Wind Damage in Conifer Stands on the Olympic Peninsula?

2007 ◽  
Vol 22 (4) ◽  
pp. 285-296 ◽  
Author(s):  
Scott D. Roberts ◽  
Constance A. Harrington ◽  
Karl R. Buermeyer
Keyword(s):  
Structural Diversity ◽  
Variable Density ◽  
Canopy Gaps ◽  
Wind Damage ◽  
Olympic Peninsula ◽  
Growing Seasons ◽  
Silvicultural Treatments ◽  
Stand Structural Diversity ◽  
Risk Of Wind Damage ◽  
Damage Risk

Abstract Silvicultural treatments designed to enhance stand structural diversity may result in increased wind damage. The ability to avoid conditions that might lead to excessive wind damage would benefit forest managers. We analyzed wind damage following implementation of a variable-density thinning at four sites on the Olympic National Forest in northwest Washington. The prescription created small canopy gaps and retained unthinned patches within a uniformly thinned matrix, thus creating substantial amounts of internal edge. Our objective was to determine whether variable-density thinning resulted in elevated wind damage and whether the damage was spatially related to elements of the treatment, i.e., canopy gaps and uncut patches. Wind damage on the thinned plots averaged slightly more than 8.0 trees/ha. Although precise determinations of residual stem densities were not available, we estimate that total wind damage amounted to 1.3% of total stems remaining following treatment. Approximately 80% of the wind damage was blowdown, the remaining damage being stem breakage, leaning, or bowing. Nearly 54% of the damaged stems were less than 20 cm dbh. The maximum amount of damage observed was 51 trees/ha, but only 3 of 13 thinned plots had wind damage exceeding 7 trees/ha. The overall level of wind damage across all thinned plots after two growing seasons was not statistically greater than on unthinned control plots. Internal edges created by gaps, skid trails, and unthinned patches did not inherently increase wind damage risk; however, where gaps were located in topographically vulnerable positions, greater wind damage did occur. Overall wind damage was not excessive on any of the plots, and after 2 years, all residual stands remained intact and in a manageable condition. Our preliminary results suggest that variable-density thinning that includes creation of small canopy gaps does not necessarily predispose stands to greater risk of wind damage than uniform thinning. However, care must be taken in locating gaps and skid trails away from topographically vulnerable positions.

Integrating the risk of wind damage into forest planning

2009 ◽  
Vol 258 (7) ◽  
pp. 1567-1577 ◽  
Author(s):  
T. Heinonen ◽  
T. Pukkala ◽  
V.-P. Ikonen ◽  
H. Peltola ◽  
A. Venäläinen ◽  
...  
Keyword(s):  
Wind Damage ◽  
Forest Planning ◽  
Risk Of Wind Damage

Simulations of the influence of clear-cutting on the risk of wind damage on a regional scale over a 20-year period

2006 ◽  
Vol 36 (9) ◽  
pp. 2247-2258 ◽  
Author(s):  
Hongcheng Zeng ◽  
Heli Peltola ◽  
Ari Talkkari ◽  
Harri Strandman ◽  
Ari Venäläinen ◽  
...  
Keyword(s):  
Case Studies ◽  
Regional Scale ◽  
Wind Damage ◽  
Average Risk ◽  
Management Options ◽  
Alternative Management ◽  
Clear Cutting ◽  
Risk Of Wind Damage ◽  
Forest Managers

The aim of this study was to integrate component models for tree growth, wind damage, and airflow to assess the consequences of alternative forest-management options on the long-term risk of wind damage on a regional scale. This work could help forest managers to identify possible vulnerable edges and determine the probability of risk for alternative management plans. This new, integrated system was applied to assessing the risk of wind damage over a 20-year period on three alternative management choices. The risk was compared for the current forest edges without creating new edges (case study I) and situations where new edges were created through different clear-cut options (case studies II and III). Case study II represented more intensive cuttings compared with case study III (over four times more timber was cut). It was found that despite intensive cuttings in case study II, only 15% and 7% fewer vulnerable edges were found on average (risk probability class ≥0.1%) in case studies I and III, respectively. Therefore, forest managers must consider the possible risk of wind damage when harvesting timber.

scholarly journals Interpreting the socio-technical interactions within a wind damage–artificial neural network model for community resilience

2020 ◽  
Vol 7 (11) ◽  
pp. 200922
Author(s):  
Stephanie F. Pilkington ◽  
Hussam N. Mahmoud
Keyword(s):  
Spatial Distribution ◽  
Graph Theory ◽  
Structural Damage ◽  
Black Box ◽  
Wind Pressure ◽  
Wind Damage ◽  
Wind Loading ◽  
Physical Damage ◽  
Artificial Neural ◽  
Wind Events

The use of machine learning has grown in popularity in various disciplines. Despite the popularity, the apparent ‘black box’ nature of such tools continues to be an area of concern. In this article, we attempt to unravel the complexity of this black box by exploring the use of artificial neural networks (ANNs), coupled with graph theory, to model and interpret the spatial distribution of building damage from extreme wind events at a community level. Structural wind damage is a topic that is mostly well understood for how wind pressure translates to extreme loading on a structure, how debris can affect that loading and how specific social characteristics contribute to the overall population vulnerability. While these themes are widely accepted, they have proven difficult to model in a cohesive manner, which has led primarily to physical damage models considering wind loading only as it relates to structural capacity. We take advantage of this modelling difficulty to reflect on two different ANN models for predicting the spatial distribution of structural damage due to wind loading. Through graph theory analysis, we study the internal patterns of the apparent black box of artificial intelligence of the models and show that social parameters are key to predict structural damage.

scholarly journals Active Acquisition for multimodal neuroimaging

2018 ◽  
Vol 3 ◽  
pp. 145
Author(s):  
James H. Cole ◽  
Romy Lorenz ◽  
Fatemeh Geranmayeh ◽  
Tobias Wood ◽  
Peter Hellyer ◽  
...  
Keyword(s):  
Data Acquisition ◽  
Biomarker Discovery ◽  
Statistical Modelling ◽  
Outcome Variable ◽  
Exact Nature ◽  
Real Time Analysis ◽  
Alternative Approach ◽  
The Many ◽  
Clinical Conditions ◽  
Rapid Data Acquisition

In many clinical and scientific situations the optimal neuroimaging sequence may not be known prior to scanning and may differ for each individual being scanned, depending on the exact nature and location of abnormalities. Despite this, the standard approach to data acquisition, in such situations, is to specify the sequence of neuroimaging scans prior to data acquisition and to apply the same scans to all individuals. In this paper, we propose and illustrate an alternative approach, in which data would be analysed as it is acquired and used to choose the future scanning sequence: Active Acquisition. We propose three Active Acquisition scenarios based around multiple MRI modalities. In Scenario 1, we propose a simple use of near-real time analysis to decide whether to acquire more or higher resolution data, or acquire data with a different field-of-view. In Scenario 2, we simulate how multimodal MR data could be actively acquired and combined with a decision tree to classify a known outcome variable (in the simple example here, age). In Scenario 3, we simulate using Bayesian optimisation to actively search across multiple MRI modalities to find those which are most abnormal. These simulations suggest that by actively acquiring data, the scanning sequence can be adapted to each individual. We also consider the many outstanding practical and technical challenges involving normative data acquisition, MR physics, statistical modelling and clinical relevance. Despite these, we argue that  Active Acquisition allows for potentially far more powerful, sensitive or rapid data acquisition, and may open up different perspectives on individual differences, clinical conditions, and biomarker discovery.

Wind damage over 21 years across different levels of tree removal in natural-origin mixed forests of northwestern British Columbia

2020 ◽  
Vol 50 (9) ◽  
pp. 946-952 ◽  
Author(s):  
K. David Coates ◽  
Erica B. Lilles ◽  
Amalesh Dhar ◽  
Erin C. Hall
Keyword(s):  
Tree Species ◽  
Basal Area ◽  
Structural Diversity ◽  
Wind Damage ◽  
Managed Forests ◽  
Partial Cutting ◽  
Forestry Practices ◽  
Management Objectives ◽  
Standing Trees ◽  
Risk Of Wind Damage

In many regions, forestry practices are shifting to partial harvesting approaches that seek to maintain species and structural diversity in managed forests. We monitored windthrow for 21 years following partial cutting treatments with 0%, 30%, and 60% removal in a large, replicated experiment located in mixed-species mature and old-growth forests of fire origin. There was no evidence that wind damage to merchantable trees (≥17.5 cm) varied among the three removal treatments. We found no evidence of a short-term spike in susceptibility to windthrow after partial cutting during the initial years following treatment. Over 21 years, a total basal area of 2.4 m2·ha–1 was damaged, which was 5.9% of the original standing basal area at the start of the experiment. We found clear differences in susceptibility to windthrow among the different tree species. The percentage of original standing trees that were windthrown varied from 0% to 23.7%. Eight of nine species had ≤10% damage over the monitoring period. Foresters should be aware of differences among tree species in risk of wind damage but should not use a general concern about susceptibility to windthrow as a reason to avoid partial cutting systems (that can achieve a diversity of management objectives) in structurally diverse, multispecies forests.

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