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Forests, Volume 7, Issue 5 (May 2016) – 18 articles

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1547 KiB  
Article
The Effects of Disturbance History on Ground-Layer Plant Community Composition in British Columbia
by Michael Ton and Meg A. Krawchuk
Forests 2016, 7(5), 109; https://doi.org/10.3390/f7050109 - 21 May 2016
Cited by 6 | Viewed by 5178
Abstract
Plant communities are sensitive to perturbations and may display alternative recovery pathways depending on disturbance history. In sub-boreal lodgepole pine forests of central interior British Columbia, Canada, fire and logging are two widespread landscape disturbances that overlap in many regions. We asked whether [...] Read more.
Plant communities are sensitive to perturbations and may display alternative recovery pathways depending on disturbance history. In sub-boreal lodgepole pine forests of central interior British Columbia, Canada, fire and logging are two widespread landscape disturbances that overlap in many regions. We asked whether cumulative, short-interval disturbance from logging and fire resulted in different ground-layer plant communities than resulted from fire alone. Using field-collected data, we compared the taxonomic composition and functional traits of 3-year old plant communities that were either harvested 6-to-13 years prior, or not harvested prior to being burned in a large stand-replacing fire. The taxonomic composition diverged between the two treatments, driven primarily by differences in a few key indicator species such as Petasites frigidus and Vaccinium membranaceum. Analysis of individual species’ morphological traits indicated that only a few species vary in size in relation to disturbance history. Our data suggest that a history of forest harvest leaves a subtle footprint on post-fire ground-layer plant communities at early stages of succession. Full article
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2848 KiB  
Article
Changes of Chemical and Biological Properties of Distinct Forest Floor Layers after Wood Ash Application in a Norway Spruce Stand
by Erika Gömöryová, Viliam Pichler, Slávka Tóthová and Dušan Gömöry
Forests 2016, 7(5), 108; https://doi.org/10.3390/f7050108 - 21 May 2016
Cited by 11 | Viewed by 4116
Abstract
The effect of wood ash (WA) fertilisation on chemical and biological properties of forest floor layers was studied in a Norway spruce (Picea abies (L.) Karst.) stand in the central part of Slovakia at an altitude of 1300 m above sea level. [...] Read more.
The effect of wood ash (WA) fertilisation on chemical and biological properties of forest floor layers was studied in a Norway spruce (Picea abies (L.) Karst.) stand in the central part of Slovakia at an altitude of 1300 m above sea level. In the forest floor, litter (OL), fragmented (OF), and humic (OH) horizons with average thickness of 1.5, 2, and 4 cm, respectively, could be distinguished. Three replicates of two wood ash treatments (3 and 6 t·ha−1) and a control were established in the autumn of 2012. Soil samples from OL, OF, OH and A-horizon were taken 0.5, 1, 6 and 12 months after the WA application. In soil samples chemical (pH, C and N content, C:N ratio, concentration of exchangeable Ca, Mg and K) and microbial properties (basal respiration, catalase activity, structure of microbial community based on BIOLOG assay) were determined. Our results showed that the changes in microbial and chemical properties do not occur simultaneously in particular horizons. WA application in autumn lead to a significant increase in pH, base cation concentration, and distinct losses in C and N content in the OL layer in the first month; however, at the beginning of the vegetation period, the most pronounced effect of WA was observed in OF and especially OH horizons; no changes were found in the A-horizon. Different properties of particular forest floor horizons led to a vertical stratification of the microbial community. Each forest floor horizon had particular properties, leading to a vertical stratification of the microbial community; deeper horizons had more homogenous functional groups. Full article
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2214 KiB  
Article
Rating a Wildfire Mitigation Strategy with an Insurance Premium: A Boreal Forest Case Study
by Georgina Rodriguez-Baca, Frédéric Raulier and Alain Leduc
Forests 2016, 7(5), 107; https://doi.org/10.3390/f7050107 - 13 May 2016
Cited by 4 | Viewed by 5232
Abstract
Risk analysis entails the systematic use of historical information to determine the frequency, magnitude and effects of unexpected events. Wildfire in boreal North America is a key driver of forest dynamics and may cause very significant economic losses. An actuarial approach to risk [...] Read more.
Risk analysis entails the systematic use of historical information to determine the frequency, magnitude and effects of unexpected events. Wildfire in boreal North America is a key driver of forest dynamics and may cause very significant economic losses. An actuarial approach to risk analysis based on cumulative probability distributions was developed to reduce the adverse effects of wildfire. To this effect, we developed spatially explicit landscape models to simulate the interactions between harvest, fire and forest succession over time in a boreal forest of eastern Canada. We estimated the amount of reduction of timber harvest necessary to build a buffer stock of sufficient size to cover fire losses and compared it to an insurance premium estimated in units of timber volume from the probability of occurrence and the amount of damage. Overall, the timber harvest reduction we applied was much more costly than the insurance premium even with a zero interest rate. This is due to the fact that the insurance premium is directly related to risk while the timber harvest reduction is not and, as a consequence, is much less efficient. These results, especially the comparison with a standard indicator such as an insurance premium, have useful implications at the time of choosing a mitigation strategy to protect timber supplies against risk without overly diminishing the provision of services from the forest. They are also promoting the use of insurance against disastrous events in forest management planning. Full article
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1402 KiB  
Article
What Are the Impacts of Deforestation on the Harvest of Non-Timber Forest Products in Central Africa?
by Pauline Gillet, Cédric Vermeulen, Jean-Louis Doucet, Elisabet Codina, Charlotte Lehnebach and Laurène Feintrenie
Forests 2016, 7(5), 106; https://doi.org/10.3390/f7050106 - 12 May 2016
Cited by 11 | Viewed by 5809
Abstract
The objective of the study is to evaluate the impact of forest transition on non-timber forest product (NTFP) harvesting in Central Africa. We analyze the evolution of several parameters, including distance from NTFP harvest site to road, proportion of dietary intake and villagers’ [...] Read more.
The objective of the study is to evaluate the impact of forest transition on non-timber forest product (NTFP) harvesting in Central Africa. We analyze the evolution of several parameters, including distance from NTFP harvest site to road, proportion of dietary intake and villagers’ incomes. The research is based on field surveys, participatory mapping and the geolocation of activities in three study sites representing different stages along the Mather’s forest transition curve: (i) intact forest; (ii) partially degraded forest; and (iii) small areas of degraded forest with plantations of useful trees. The results show that the maximum distance from harvest site to road is higher in Site 2 compared to Site 1 as a consequence of a lower availability of NTFPs; and that this distance is significantly lower in Site 3 due to a drastically smaller village territory. The diversity of bushmeat decreases as game evolves from large to small species, commensurate with the progression of forest transition. As a consequence, there is also a reduction in the proportion of these products represented both in household dietary intake and cash income. This analysis establishes a strong link between the Mather’s forest transition curve and a decline in the importance of NTFPs in village production and livelihoods. Full article
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1522 KiB  
Article
Vulnerability of Commercial Tree Species to Water Stress in Logged Forests of the Guiana Shield
by Hélène Fargeon, Mélaine Aubry-Kientz, Olivier Brunaux, Laurent Descroix, Romain Gaspard, Stéphane Guitet, Vivien Rossi and Bruno Hérault
Forests 2016, 7(5), 105; https://doi.org/10.3390/f7050105 - 12 May 2016
Cited by 17 | Viewed by 5327
Abstract
The future of tropical managed forests is threatened by climate change. In anticipation of the increase in the frequency of drought episodes predicted by climatic models for intertropical regions, it is essential to study commercial trees’ resilience and vulnerability to water stress by [...] Read more.
The future of tropical managed forests is threatened by climate change. In anticipation of the increase in the frequency of drought episodes predicted by climatic models for intertropical regions, it is essential to study commercial trees’ resilience and vulnerability to water stress by identifying potential interaction effects between selective logging and stress due to a lack of water. Focusing on 14 species representing a potential or acknowledged commercial interest for wood production in the Guiana Shield, a joint model coupling growth and mortality for each species was parametrized, including a climatic variable related to water stress and the quantity of aboveground biomass lost after logging. For the vast majority of the species, water stress had a negative impact on growth rate, while the impact of logging was positive. The opposite results were observed for the mortality. Combining results from growth and mortality models, we generate vulnerability profiles and ranking from species apparently quite resistant to water stress (Chrysophyllum spp., Goupia glabra Aubl., Qualea rosea Aubl.), even under logging pressure, to highly vulnerable species (Sterculia spp.). In light of our results, forest managers in the Guiana Shield may want to conduct (i) a conservation strategy of the most vulnerable species and (ii) a diversification of the logged species. Conservation of the already-adapted species may also be considered as the most certain way to protect the tropical forests under future climates. Full article
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1202 KiB  
Article
Joining Criteria for Harmonizing European Forest Available for Wood Supply Estimates. Case Studies from National Forest Inventories
by Christoph Fischer, Patrizia Gasparini, Martin Nylander, John Redmond, Laura Hernandez, Urs-Beat Brändli, Alejandro Pastor, Maria Rizzo and Iciar Alberdi
Forests 2016, 7(5), 104; https://doi.org/10.3390/f7050104 - 12 May 2016
Cited by 19 | Viewed by 5264
Abstract
For national and international reporting on forest available for wood supply (FAWS), harmonized data are needed. This information is required as forests provide goods for various sectors like the timber industry or the bioenergy sector. The effect of applying different thresholds to the [...] Read more.
For national and international reporting on forest available for wood supply (FAWS), harmonized data are needed. This information is required as forests provide goods for various sectors like the timber industry or the bioenergy sector. The effect of applying different thresholds to the three restriction classes (environmental, social and economic restriction) within the proposed reference definition for FAWS was evaluated. We applied the reference definition for FAWS to national data sets provided by five European National Forest Inventories using harmonized thresholds. The effects on FAWS area and growing stock were evaluated for each restriction and threshold. All countries within this study could report on protected areas. Social restrictions were not applied in any country, data on other restrictions are available but definitions vary. The application of common thresholds for restrictions proved difficult as effects vary between countries. The economic restriction is the most challenging to assess as many countries do not have corresponding data for direct calculation of, e.g., harvesting costs. Using proxies for harvesting costs was difficult, as common thresholds may not be applied in different countries. For standardized reporting, a FAWS definition should be developed that utilizes existing, harmonized indicators to describe restrictions. Full article
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2798 KiB  
Article
Regional Instability in the Abundance of Open Stands in the Boreal Forest of Eastern Canada
by Rija Rapanoela, Frédéric Raulier and Sylvie Gauthier
Forests 2016, 7(5), 103; https://doi.org/10.3390/f7050103 - 12 May 2016
Cited by 6 | Viewed by 4906
Abstract
Fires are a key disturbance of boreal forests. In fact, they are the main source of renewal and evolution for forest stands. The variability of fire through space and time results in a diversified forest mosaic, altering their species composition, structure and productivity. [...] Read more.
Fires are a key disturbance of boreal forests. In fact, they are the main source of renewal and evolution for forest stands. The variability of fire through space and time results in a diversified forest mosaic, altering their species composition, structure and productivity. A resilient forest is assumed to be in a state of dynamic equilibrium with the fire regime, so that the composition, age structure and succession stages of forests should be consistent with the fire regime. Dense spruce-moss stands tend, however, to diminish in favour of more open stands similar to spruce-lichen stands when subjected to more frequent and recurring disturbances. This study therefore focused on the effects of spatial and temporal variations in burn rates on the proportion of open stands over a large geographic area (175,000 km2) covered by black spruce (Picea mariana (Mill.) Britton, Sterns, Poggenb.). The study area was divided into 10 different zones according to burn rates, as measured using fire-related data collected between 1940 and 2006. To test if the abundance of open stands was unstable over time and not in equilibrium with the current fire regime, forest succession was simulated using a landscape dynamics model that showed that the abundance of open stands should increase progressively over time in zones where the average burn rate is high. The proportion of open stands generated during a specific historical period is correlated with the burn rate observed during the same period. Rising annual burn rates over the past two decades have thereby resulted in an immediate increase in the proportion of open stands. There is therefore a difference between the current proportion of open stands and the one expected if vegetation was in equilibrium with the disturbance regime, reflecting an instability that may significantly impact the way forest resources are managed. It is apparent from this study that forestry planning should consider the risks associated with the temporal variability of fire regimes on the forest ecosystem, as the resulting changes can have a significant impact on biodiversity and allowable cut estimates. Full article
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922 KiB  
Article
Time Efficiency of Selected Types of Adjacency Constraints in Solving Unit Restriction Models
by Jan Kašpar, Róbert Marušák and Pete Bettinger
Forests 2016, 7(5), 102; https://doi.org/10.3390/f7050102 - 11 May 2016
Cited by 7 | Viewed by 3915
Abstract
Spatial restrictions of harvesting have been extensively studied due to a number of environmental, social and legal regulations. Many spatial restrictions are defined by adjacency constraints, for which a number of algorithms have been developed. Research into the unit restriction model (URM) using [...] Read more.
Spatial restrictions of harvesting have been extensively studied due to a number of environmental, social and legal regulations. Many spatial restrictions are defined by adjacency constraints, for which a number of algorithms have been developed. Research into the unit restriction model (URM) using a branch and bound algorithm focused on decreasing the number of adjacency constraints in harvest scheduling models, since the early solvers have been limited by the number of constraints and integer decision variables. However, this approach can lead to a loss of efficiency in solving mixed integer models. Recent improvements in commercial solvers and personal computers have made the reduction of constraints less relevant, since many solvers now accept an unlimited number of constraints and decision variables. The aim of this paper was to compare the time efficiency of solving unit restriction harvest scheduling models with different types of adjacency constraints using a commercial solver. The presented results indicate that the type of adjacency constraints can have a significant effect on the solving time and therefore could be a crucial factor of the time required for developing forest plans. We note that pairwise adjacency constraints may be sufficient today for addressing unit restriction forest harvest scheduling problems. Full article
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1350 KiB  
Communication
Pattern and Drivers of White-Tailed Deer (Odocoileus virginianus) Herbivory on Tree Saplings across a Plateau Landscape
by Jonathan P. Evans, Callie A. Oldfield, Kristen K. Cecala, John Kevin Hiers, Chris Van De Ven and Meg M. Armistead
Forests 2016, 7(5), 101; https://doi.org/10.3390/f7050101 - 06 May 2016
Cited by 4 | Viewed by 6994
Abstract
White-tailed deer (Odocoileus virginianus) populations are impacting long-term regeneration across eastern United States forests. Deer distribution and resulting herbivory patterns are variable across a landscape due to habitat patchiness and topography. It is poorly understood how features associated with topography control [...] Read more.
White-tailed deer (Odocoileus virginianus) populations are impacting long-term regeneration across eastern United States forests. Deer distribution and resulting herbivory patterns are variable across a landscape due to habitat patchiness and topography. It is poorly understood how features associated with topography control deer herbivory. We examined the heterogeneity of deer herbivory as it affects sapling densities across a single forest-type landscape on the Cumberland Plateau. The 1242 hectare site represented a peninsula of tableland that transitioned from developed land to forest and was surrounded on three sides by a bluff, irregularly punctuated by drainages. We examined the spatial variability of deer impacts on sapling density and modeled the relative importance of plateau accessibility features related to topography, proximity to edge, and deer culling as predictors of sapling variation. We used a stratified random design to sample sapling density across the landscape in 2012 and 2015. The intensity of deer herbivory on saplings varied, with the fewest saplings in forests surrounded by residential development. Our model predicted that plateau accessibility measures best determined sapling densities, followed by distance from edge and deer culling measures. Our results suggest that herbivory impacts may not be homogeneous in a contiguous uniform landscape if there are topographic barriers. Full article
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912 KiB  
Article
Decision Support for Participatory Forest Planning Using AHP and TOPSIS
by Hilma Nilsson, Eva-Maria Nordström and Karin Öhman
Forests 2016, 7(5), 100; https://doi.org/10.3390/f7050100 - 05 May 2016
Cited by 48 | Viewed by 8470
Abstract
Long-term forest management planning often involves several stakeholders with conflicting objectives, creating a complex decision process. Multiple-criteria decision analysis (MCDA) presents a promising framework for finding solutions in terms of suitable trade-offs among the objectives. However, many of the MCDA methods that have [...] Read more.
Long-term forest management planning often involves several stakeholders with conflicting objectives, creating a complex decision process. Multiple-criteria decision analysis (MCDA) presents a promising framework for finding solutions in terms of suitable trade-offs among the objectives. However, many of the MCDA methods that have been implemented in forest management planning can only be used to compare and evaluate a limited number of management plans, which increases the risk that the most suitable plan is not included in the decision process. The aim of this study is to test whether the combination of two MCDA methods can facilitate the evaluation of a large number of strategic forest management plans in a situation with multiple objectives and several stakeholders. The Analytic Hierarchy Process (AHP) was used to set weights for objectives based on stakeholder preferences and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was used to produce an overall ranking of alternatives. This approach was applied to a case study of the Vilhelmina municipality, northern Sweden. The results show that the combination of AHP and TOPSIS is easy to implement in participatory forest planning and takes advantage of the capacity of forest decision support systems to create a wide array of management plans. This increases the possibility that the most suitable plan for all stakeholders will be identified. Full article
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1044 KiB  
Article
The Speed of Invasion: Rates of Spread for Thirteen Exotic Forest Insects and Diseases
by Alexander M. Evans
Forests 2016, 7(5), 99; https://doi.org/10.3390/f7050099 - 04 May 2016
Cited by 22 | Viewed by 5555
Abstract
Invasive, exotic insects and diseases have a devastating effect on North American forests. The rate of spread, or range expansion, is one of the main determinants of an invasive organism’s impact, and can play a major role in structuring management response options. To [...] Read more.
Invasive, exotic insects and diseases have a devastating effect on North American forests. The rate of spread, or range expansion, is one of the main determinants of an invasive organism’s impact, and can play a major role in structuring management response options. To better understand how exotic organisms have spread through our forests, this study employs a consistent, rigorous analytical framework to analyze a comprehensive geospatial database for the spread of seven exotic insects and six diseases. This study includes new data for six insects and two diseases in combination with five invasive species previously analyzed using the same technique. The quantile regression analysis of over 3000 records of infestation over the preceding century show that the rate of spread of invasive forest insects and diseases ranges from 4.2 km·year−1 to 57.0 km·year−1. The slowest disease spread was white pine blister rust (Cronartium ribicola) at 7.4 km·year−1 while the most rapid disease spread was chestnut blight (Cryphonectria parasitica) at 31.3 km·year−1. The slowest insect spread was balsam woolly adelgid (Adelges piceae) (4.2 km·year−1) while the fastest was emerald ash borer (Agrilus planipennis) at 57.0 km·year−1. Species that can fly long distances or are vectored by flying insects have spread faster than those that are passively dispersed. This analysis highlights the difficulty of estimating spread rates from studies of individual dispersal or flight distances, but the estimated spread rates in this study are generally in line with previous estimates. Full article
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2813 KiB  
Article
Carbon Dynamics of Pinus palustris Ecosystems Following Drought
by Gregory Starr, Christina L. Staudhammer, Susanne Wiesner, Sujit Kunwor, Henry W. Loescher, Andres F. Baron, Andrew Whelan, Robert J. Mitchell and Lindsay Boring
Forests 2016, 7(5), 98; https://doi.org/10.3390/f7050098 - 29 Apr 2016
Cited by 26 | Viewed by 6004
Abstract
Drought can affect forest structure and function at various spatial and temporal scales. Forest response and recovery from drought may be a result of position within landscape. Longleaf pine forests in the United States have been observed to reduce their carbon sequestration capacity [...] Read more.
Drought can affect forest structure and function at various spatial and temporal scales. Forest response and recovery from drought may be a result of position within landscape. Longleaf pine forests in the United States have been observed to reduce their carbon sequestration capacity during drought. We collected eddy covariance data at the ends of an edaphic longleaf pine gradient (xeric and mesic sites) over seven years; two years of normal rainfall were followed by 2.5 years of drought, then 2.5 years of normal or slightly above-average rainfall. Drought played a significant role in reducing the physiological capacity of the sites and was compounded when prescribed fire occurred during the same periods. The mesic site has a 40% greater basal area then the xeric site, which accounts for its larger sequestration capacity; however, both sites show the same range of variance in fluxes over the course of the study. Following drought, both sites became carbon sinks. However, the xeric site had a longer carry-over effect and never returned to pre-drought function. Although this study encompassed seven years, we argue that longer studies with greater spatial variance must be undertaken to develop a more comprehensive understanding of forest response to changing climate. Full article
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1234 KiB  
Article
A Decade Trend of Total Factor Productivity of Key State-Owned Forestry Enterprises in China
by Hongqiang Yang, Tian Yuan, Xiaobiao Zhang and Suyan Li
Forests 2016, 7(5), 97; https://doi.org/10.3390/f7050097 - 29 Apr 2016
Cited by 26 | Viewed by 4982
Abstract
State-owned forestry enterprises are important elements of the forestry economy in China. The operational efficiency of such enterprises depends on technological progress and other input factors. Total factor productivity (TFP) is an important means to evaluate the efficiency of technical elements. The growth [...] Read more.
State-owned forestry enterprises are important elements of the forestry economy in China. The operational efficiency of such enterprises depends on technological progress and other input factors. Total factor productivity (TFP) is an important means to evaluate the efficiency of technical elements. The growth of production efficiency can be classified into efficiency variation and technical variation. The TFP of 135 key state-owned forestry enterprises in the northeast, southwest, and northwest regions of China in 2001–2011 was measured through Malmquist–data envelopment analysis. The technological progress of the state-owned forestry enterprises positively affected TFP variation, but technical efficiency only slightly increased and scale efficiency even negatively affected TFP variation. The average growth rate of TFP in the northwest region is higher than those in the northeast and southwest regions. The Western Development Program of China increasingly contributes to the economic development of western areas. The increasing investment of the government in science and technology accelerates the development of forestry economy in China. Full article
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1911 KiB  
Article
Predicting Aboveground Biomass in Second Growth Coast Redwood: Comparing Localized with Generic Allometric Models
by Anil Raj Kizha and Han-Sup Han
Forests 2016, 7(5), 96; https://doi.org/10.3390/f7050096 - 27 Apr 2016
Cited by 10 | Viewed by 6354
Abstract
Biomass amounts predicted by generalized models are often not applicable for small regions. Localized allometric models were developed relating tree/biomass components to diameter at breast height (dbh) for coast redwood (Sequoia sempervirens (D. Don) Endl.) from an industrial timberland in northwestern California, [...] Read more.
Biomass amounts predicted by generalized models are often not applicable for small regions. Localized allometric models were developed relating tree/biomass components to diameter at breast height (dbh) for coast redwood (Sequoia sempervirens (D. Don) Endl.) from an industrial timberland in northwestern California, USA. dbh for the candidate trees ranged from 2.54 cm to 84.07 cm. Biomass of tree components, such as bole, foliage, bark, live and dead branches, along with the total aboveground biomass (TAGB) were estimated. Other tree dimensions such as tree height, height to live crown, weight and volume of bole wood were also modeled. Localized allometric models were able to explain more than 93% of the variability for most of the tree components (p < 0.001). Biomass amounts predicted from the widely used generalized models were different from that estimated by the localized allometric model developed from this study. However, the results presented in this study should be used carefully to predict the biomass components, if applied outside the stated dbh range or stand conditions on which this study was based. Full article
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3296 KiB  
Article
Metabarcoding of Bacteria Associated with the Acute Oak Decline Syndrome in England
by Melanie Sapp, Erin Lewis, Stephen Moss, Ben Barrett, Susan Kirk, John G. Elphinstone and Sandra Denman
Forests 2016, 7(5), 95; https://doi.org/10.3390/f7050095 - 26 Apr 2016
Cited by 29 | Viewed by 6795
Abstract
Outbreaks of acute oak decline (AOD) have been documented in England from 2006. Both species of native oaks (Quercus robur and Quercus petraea) are affected. To complement isolation efforts for identification of putative causative biotic agents and increase our understanding of [...] Read more.
Outbreaks of acute oak decline (AOD) have been documented in England from 2006. Both species of native oaks (Quercus robur and Quercus petraea) are affected. To complement isolation efforts for identification of putative causative biotic agents and increase our understanding of bacteria associated with oak tissue, five sites in England were chosen for this study. Samples of outer bark, inner bark, sapwood and heartwood were taken from healthy oak and trees with symptoms at varying stages of the syndrome. Furthermore, larval galleries attributed to infestation with Agrilus biguttatus were included. After DNA extraction and amplification of the V3–V5 fragment of the bacterial 16S rRNA genes by pyrosequencing, the dataset was analyzed to identify patterns in bacterial communities in oak tissue samples with and without AOD symptoms at each site. The composition of bacterial communities differed greatly according to the site from which the samples were obtained. Within each site, the composition of the bacteria associated with symptomatic tissue varied between advanced stages of the syndrome and healthy tissue. Key players in healthy and symptomatic tissue were identified and included members of the Gammaproteobacteria related to Pseudomonas sp. or Brenneria goodwinii and members of the Firmicutes. Full article
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3760 KiB  
Article
Forecasting Monthly Prices of Japanese Logs
by Tetsuya Michinaka, Hirofumi Kuboyama, Kazuya Tamura, Hiroyasu Oka and Nobuyuki Yamamoto
Forests 2016, 7(5), 94; https://doi.org/10.3390/f7050094 - 26 Apr 2016
Cited by 10 | Viewed by 4789
Abstract
Forecasts of prices can help industries in their risk management. This is especially true for Japanese logs, which experience sharp fluctuations in price. In this research, the authors used an exponential smoothing method (ETS) and autoregressive integrated moving average (ARIMA) models to forecast [...] Read more.
Forecasts of prices can help industries in their risk management. This is especially true for Japanese logs, which experience sharp fluctuations in price. In this research, the authors used an exponential smoothing method (ETS) and autoregressive integrated moving average (ARIMA) models to forecast the monthly prices of domestic logs of three of the most important species in Japan: sugi (Japanese cedar, Cryptomeria japonica D. Don), hinoki (Japanese cypress, Chamaecyparis obtusa (Sieb. et Zucc.) Endl.), and karamatsu (Japanese larch, Larix kaempferi (Lamb.) Carr.). For the 12-month forecasting periods, forecasting intervals of 80% and 95% were given. By measuring the accuracy of forecasts of 12- and 6-month forecasting periods, it was found that ARIMA gave better results than did the ETS in the majority of cases. However, the combined method of averaging ETS and ARIMA forecasts gave the best results for hinoki in several cases. Full article
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2422 KiB  
Article
Landscape Biology of Western White Pine: Implications for Conservation of a Widely-Distributed Five-Needle Pine at Its Southern Range Limit
by Patricia E. Maloney, Andrew J. Eckert, Detlev R. Vogler, Camille E. Jensen, Annette Delfino Mix and David B. Neale
Forests 2016, 7(5), 93; https://doi.org/10.3390/f7050093 - 26 Apr 2016
Cited by 2 | Viewed by 5164
Abstract
Throughout much of the range of western white pine, Pinus monticola Dougl., timber harvesting, fire exclusion and the presence of Cronartium ribicola J. C. Fisch., the white pine blister rust (WPBR) pathogen, have led to negative population and genetic consequences. To address these [...] Read more.
Throughout much of the range of western white pine, Pinus monticola Dougl., timber harvesting, fire exclusion and the presence of Cronartium ribicola J. C. Fisch., the white pine blister rust (WPBR) pathogen, have led to negative population and genetic consequences. To address these interactions, we examined population dynamics and genetic diversity in 10 populations of western white pine in upper montane forests of the Lake Tahoe Basin. We documented negative population trends for three of the 10 populations. These populations exhibited low estimated growth rates (λ), moderate to high incidences of WPBR and mountain pine beetle (MPB), and high levels of mortality. In contrast, seven populations appear to be stable (λ ≥ 1.0), with low to moderate disease and insect incidence, and evidence for genetic resistance to WPBR. Genetic diversity (HE) for a set of 160 single nucleotide polymorphisms was in the range of 0.245–0.272 across populations, and population-specific estimates of FST ranged from 0.0062 to 0.0244. Allele frequency of the Cr2 gene, which confers complete resistance to C. ribicola in western white pine, was low, averaging 0.009 for all populations sampled. However, a low frequency of pollen receptors (i.e., susceptible maternal parents pollinated by a local resistant parent) was found in nine of 10 populations. A moderate and negative relationship was found between the frequency of pollen receptors in a population and the incidence of WPBR (r2 = 0.32). In the context of an introduced pathogen, climate driven outbreaks of MPB, fire exclusion, and prolonged drought, conservation and management strategies are warranted for this species in the Lake Tahoe Basin and likely other locations in California. These strategies include gene conservation of western white pine, WPBR resistance screening, and forest restoration treatments. Full article
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654 KiB  
Communication
A Multidimensional Environmental Value Orientation Approach to Forest Recreation Area Tourism Market Segmentation
by Cheng-Ping Wang, Ching Li and Sung-Ta Liu
Forests 2016, 7(5), 92; https://doi.org/10.3390/f7050092 - 25 Apr 2016
Cited by 11 | Viewed by 4386
Abstract
This paper uses multidimensional environmental value orientations as the segmentation bases for analyzing a natural destination tourism market of the National Forest Recreation Areas in Taiwan. Cluster analyses identify two segments, Acceptance and Conditionality, within 1870 usable observations. Independent sample t test and [...] Read more.
This paper uses multidimensional environmental value orientations as the segmentation bases for analyzing a natural destination tourism market of the National Forest Recreation Areas in Taiwan. Cluster analyses identify two segments, Acceptance and Conditionality, within 1870 usable observations. Independent sample t test and crosstab analyses are applied to examine these segments’ forest value orientations, sociodemographic features, and service demands. The Acceptance group tends to be potential ecotourists, while still recognizing the commercial value of the natural resources. The Conditionality group may not possess a strong sense of ecotourism, given that its favored services can affect the environment. Overall, this article confirms the use of multidimensional environmental value orientation approaches can generate a comprehensive natural tourist segment comparison that benefits practical management decision making. Full article
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