Forests

Research

17 pages, 1167 KiB

Open AccessArticle

Spatial Distribution of Biomass and Woody Litter for Bio-Energy in Biscay (Spain)

by Esperanza Mateos and Leyre Ormaetxea

Forests 2018, 9(5), 253; https://doi.org/10.3390/f9050253 - 7 May 2018

Cited by 4 | Viewed by 3388

Abstract

Forest management has been considered a subject of interest, because they act as carbon (C) sinks to mitigate CO

_{2}

emissions and also as producers of woody litter (WL) for bio-energy. Overall, a sustainably managed system of forests and forest products contributes to [...] Read more.

Forest management has been considered a subject of interest, because they act as carbon (C) sinks to mitigate CO

_{2}

emissions and also as producers of woody litter (WL) for bio-energy. Overall, a sustainably managed system of forests and forest products contributes to carbon mitigation in a positive, stable way. With increasing demand for sustainable production, the need to effectively utilise site-based resources increases. The utilization of WL for bio-energy can help meet the need for renewable energy production. The objective of the present study was to investigate biomass production (including C sequestration) from the most representative forestry species (Pinus radiata D. Don and Ecualyptus globulus Labill) of Biscay (Spain). Data from the third and fourth Spanish Forest Inventories (NFI3-2005 and NFI4-2011) were used. We also estimated the potential WL produced in the forest activities. Our findings were as follows: Forests of Biscay stored 12.084 Tg of biomass (dry basis), with a mean of 147.34 Mg ha

^{- 1}

in 2005 and 14.509 Tg of biomass (dry basis), with a mean of 179.82 Mg ha

^{- 1}

in 2011. The total equivalent CO

_{2}

in Biscay’s forests increased by 1.629 Tg year

^{- 1}

between 2005 and 2011. The study shows that the energy potential of carbon accumulated in the WL amounted to 1283.2 million MJ year

^{- 1}

. These results suggest a considerable potential for energy production. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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16 pages, 57041 KiB

Open AccessArticle

Traffic-Induced Changes and Processes in Forest Road Aggregate Particle-Size Distributions

by Hakjun Rhee, James Fridley and Deborah Page-Dumroese

Forests 2018, 9(4), 181; https://doi.org/10.3390/f9040181 - 3 Apr 2018

Cited by 6 | Viewed by 3780

Abstract

Traffic can alter forest road aggregate material in various ways, such as by crushing, mixing it with subgrade material, and sweeping large-size, loose particles (gravel) toward the outside of the road. Understanding the changes and physical processes of the aggregate is essential to [...] Read more.

Traffic can alter forest road aggregate material in various ways, such as by crushing, mixing it with subgrade material, and sweeping large-size, loose particles (gravel) toward the outside of the road. Understanding the changes and physical processes of the aggregate is essential to mitigate sediment production from forest roads and reduce road maintenance efforts. We compared the particle-size distributions of forest road aggregate from the Clearwater National Forest in Idaho, USA in three vertical layers (upper, middle, and bottom of the road aggregate), three horizontal locations (tire track, shoulder, and half-way between them), and three traffic uses (none, light (no logging vehicles), and heavy (logging vehicles and equipment)) using Tukey’s multiple comparison test. Light traffic appears to cause aggregate crushing where vehicle tires passed and caused sweeping on the road surface. Heavy traffic caused aggregate crushing at all vertical and horizontal locations, and subgrade mixing with the bottom layer at the shoulder location. Logging vehicles and heavy equipment with wide axles drove on the shoulder and exerted enough stress to cause subgrade mixing. These results can help identify the sediment source and define adequate mitigation measures to reduce sediment production from forest roads and reduce road maintenance efforts by providing information for best management practices. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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21 pages, 84275 KiB

Open AccessArticle

A Spatially Explicit Method to Assess the Economic Suitability of a Forest Road Network for Timber Harvest in Steep Terrain

by Leo Gallus Bont, Marielle Fraefel and Christoph Fischer

Forests 2018, 9(4), 169; https://doi.org/10.3390/f9040169 - 27 Mar 2018

Cited by 14 | Viewed by 5189

Abstract

Despite relatively high road density in the forests of Switzerland, a large percentage of that road network does not fulfill best practice requirements. Before upgrading or rebuilding the road network, harvesting planners must first determine which areas have insufficient access. Traditional assessment methods [...] Read more.

Despite relatively high road density in the forests of Switzerland, a large percentage of that road network does not fulfill best practice requirements. Before upgrading or rebuilding the road network, harvesting planners must first determine which areas have insufficient access. Traditional assessment methods tend to only report specific values such as road density. However, those values do not identify the exact parcels or areas that are inaccessible. Here, we present a model that assesses the economic suitability of each timbered parcel for wood-harvesting operations, including tree-felling and processing, and off- and on-road transport (hauling), based on the existing road network. The entire wood supply chain from forest (standing trees) to a virtual pile at the border of the planning unit was captured. This method was particularly designed for steep terrain and was tested in the Canton of Grisons in Switzerland. Compared with classical approaches, such as the road density concept, which only deliver average values, this new method enables planners to assess the development of a road network in a spatially explicit manner and to easily identify the reason and the location of shortcomings in the road network. Moreover, while other related spatially explicit approaches focus only on harvesting operations, the assessment method proposed here also includes limitations (road standards) of the road network. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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12 pages, 9891 KiB

Open AccessArticle

Total Weight and Axle Loads of Truck Units in the Transport of Timber Depending on the Timber Cargo

by Grzegorz Trzciński, Tadeusz Moskalik and Rafał Wojtan

Forests 2018, 9(4), 164; https://doi.org/10.3390/f9040164 - 23 Mar 2018

Cited by 24 | Viewed by 6795

Abstract

When transporting timber, the high variability of species, assortments and moisture content of the wood raw material does not allow the weight of the transported timber to be precisely determined. This often contributes to the excessive weight loading of the entire truck unit. [...] Read more.

When transporting timber, the high variability of species, assortments and moisture content of the wood raw material does not allow the weight of the transported timber to be precisely determined. This often contributes to the excessive weight loading of the entire truck unit. The aim of the research is to present the variability of the total weight of truck units with wood cargoes (GVW—gross vehicle weight) depending on the weight of the empty unit and the transported timber load, as well as to analyze the changes in GVW, unit loads of wood and load on individual truck unit axles depending on the season. This study analyzes the total weight of truck units for 376 transports of Scots pine timber at different times of the year. The total weight of the truck units depends on the weight of an empty unit and the weight of the load. GVW was determined by using a weighbridge to weigh the vehicles and then the empty unit after unloading. The weight of the load was obtained as the difference between GVW and the tare. It was found that GVW differed significantly depending on the truck unit used, ranging from 43.60–58.80 Mg, often exceeding permissible limits for public roads. The individual axle loads for various truck units were also analyzed. The obtained results indicate that these loads are more equally distributed in the case of five-axle trucks compared to six-axle ones. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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17 pages, 3645 KiB

Open AccessArticle

Treatment of Picea abies and Pinus sylvestris Stumps with Urea and Phlebiopsis gigantea for Control of Heterobasidion

by Kalle Kärhä, Ville Koivusalo, Teijo Palander and Matti Ronkanen

Forests 2018, 9(3), 139; https://doi.org/10.3390/f9030139 - 15 Mar 2018

Cited by 11 | Viewed by 5184

Abstract

Heterobasidion spp. root rot causes severe damage to forests throughout the northern temperate zone. In order to prevent Heterobasidion infection in summertime cuttings, stumps can be treated with urea or Phlebiopsis gigantea. In this study, the consumption of stump treatment materials and [...] Read more.

Heterobasidion spp. root rot causes severe damage to forests throughout the northern temperate zone. In order to prevent Heterobasidion infection in summertime cuttings, stumps can be treated with urea or Phlebiopsis gigantea. In this study, the consumption of stump treatment materials and the quality of stump treatment work were investigated. A total of 46 harvesters were examined in May–November 2016 in Finland. The average stem size of softwood removal and softwood removal per hectare explained the consumption of stump treatment material. The quality of stump treatment work was good in the study. The best coverage was achieved with the stumps of 20–39 cm diameter at stump height (d₀). It can be recommended that the harvester operator self-monitors and actively controls his/her treatment result in cutting work and sets the stump treatment equipment in a harvester if needed. The results also suggested that when cutting mostly small- and medium-diameter (d₀ ≤ 39 cm) conifers, the stump treatment guide bars with relatively few (<18) open holes are used, and at the harvesting sites of large-diameter trees, the guide bars with a relatively great (>27) number of open holes are applied. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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12 pages, 1817 KiB

Open AccessFeature PaperArticle

Postural Risk Assessment of Small-Scale Debarkers for Wooden Post Production

by Raffaele Spinelli, Giovanni Aminti, Natascia Magagnotti and Fabio De Francesco

Forests 2018, 9(3), 111; https://doi.org/10.3390/f9030111 - 2 Mar 2018

Cited by 12 | Viewed by 4092

Abstract

The study sampled six representative work sites in Northern and Central Italy, in order to assess the risk for developing musculo-skeletal disease due to poor work posture (postural risk) among the operators engaged in semi-mechanized post debarking operations. Assessment was conducted with the [...] Read more.

The study sampled six representative work sites in Northern and Central Italy, in order to assess the risk for developing musculo-skeletal disease due to poor work posture (postural risk) among the operators engaged in semi-mechanized post debarking operations. Assessment was conducted with the Ovako Working posture Analysis System (OWAS) on 1200 still frames randomly extracted from videotaped work samples. The postural risk associated with post debarking was relatively low, and varied with individual operations based on their specific set up. Postural risk was higher for the loading station compared with the unloading station, which makes a strong argument for job rotation. The study suggested that the infeed chute of small-scale debarkers might be too basic and should be further developed, in order to reduce postural risk. Obviously, better machine design should be part of an articulate strategy aimed at decreasing the postural risk and based on proper worksite organization and specific worker training. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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13 pages, 4976 KiB

Open AccessArticle

Monitoring Cable Tensile Forces of Winch-Assist Harvester and Forwarder Operations in Steep Terrain

by Franz Holzleitner, Maximilian Kastner, Karl Stampfer, Norbert Höller and Christian Kanzian

Forests 2018, 9(2), 53; https://doi.org/10.3390/f9020053 - 24 Jan 2018

Cited by 21 | Viewed by 4867

Abstract

The objective of this case study was to develop and test a specific survey protocol for monitoring tensile forces for winch-assisted harvesters and forwarders with a mounted or integrated constant-pull capstan winch technology. Based on the designed survey protocol, the interactions between work [...] Read more.

The objective of this case study was to develop and test a specific survey protocol for monitoring tensile forces for winch-assisted harvesters and forwarders with a mounted or integrated constant-pull capstan winch technology. Based on the designed survey protocol, the interactions between work phases, machine inclination, and tensile forces in typical work conditions were analysed. The established workflow, including equipment and the developed analysis routines, worked appropriately and smoothly. The working load on the cable during the study did not exceed 50% of the maximum breaking strength. A maximum tensile force peak at 56 kN was observed during delays for the forwarder, and a peak of 75.5 kN was observed for the harvester, both of which are still within the safe working load when considering a safety factor of two. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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2462 KiB

Open AccessFeature PaperArticle

Value Retention, Service Life, Use Intensity and Long-Term Productivity of Wood Chippers as Obtained from Contractor Records

by Raffaele Spinelli, Lars Eliasson and Natascia Magagnotti

Forests 2017, 8(12), 503; https://doi.org/10.3390/f8120503 - 20 Dec 2017

Cited by 9 | Viewed by 5686

Abstract

Acknowledging the absence of up-to-date empirical data on the value retention, service life and annual use of chipping machinery, in 2017 the authors surveyed the records kept by 50 contractors offering biomass chipping services. The machine fleet and operations in this survey could [...] Read more.

Acknowledging the absence of up-to-date empirical data on the value retention, service life and annual use of chipping machinery, in 2017 the authors surveyed the records kept by 50 contractors offering biomass chipping services. The machine fleet and operations in this survey could be taken as representative for most of Europe, where the biomass sector is well established and is facing further expansion. Data collection included the whole chipping unit, comprised of chipper, carrier and loader. Manually-fed units were excluded from the survey. The data pointed at a service life up to and exceeding 10,000 h and 10 years, which relieved any concerns about poor durability. Value retention was good, and may exceed that of other mainstream forestry equipment. Engine power was the main explanatory variable in any models to predict purchase price and productivity. The effect of this variable could explain most of the variability (>80%) in the purchase price and productivity data. Results also pointed at the essential equivalence in price and productivity between PTO-driven (i.e., tractor powered) and independent-engine chippers, once differences in engine power are accounted for. However, the distribution of purchase price between different components of the chipping unit was different between the two unit types, with the chipper accounting for a larger proportion of the total investment in independent-engine units. Machine power was also different, with most PTO-driven units being significantly smaller than independent-engine units, due to the limitations of existing tractors. Furthermore, half of the carriers assigned to a PTO-driven unit were subject to flexible use, i.e., they were not solely used for chipping work. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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2754 KiB

Open AccessArticle

Use, Utilization, Productivity and Fuel Consumption of Purpose-Built and Excavator-Based Harvesters and Processors in Italy

by Natascia Magagnotti, Luigi Pari and Raffaele Spinelli

Forests 2017, 8(12), 485; https://doi.org/10.3390/f8120485 - 6 Dec 2017

Cited by 18 | Viewed by 5574

Abstract

Annual use, utilization, productivity and fuel consumption of three purpose-built and three excavator-based harvesters and processors were monitored for one work year. All machines were owned and operated by private contractors and were representative of the Italian machine fleet. Despite challenging mountain terrain, [...] Read more.

Annual use, utilization, productivity and fuel consumption of three purpose-built and three excavator-based harvesters and processors were monitored for one work year. All machines were owned and operated by private contractors and were representative of the Italian machine fleet. Despite challenging mountain terrain, annual use ranged from 675 to 1525 h per year, and production from 3200 to 27,400 m³ per year. Productivity was lower for excavator-based units, and for machines working under a yarder, due to limited yarder capacity. Purpose-built machines offered higher utilization, productivity and fuel efficiency compared with excavator-based machines. Fuel consumption per m³ was 2.4 times greater for excavator-based units, compared with purpose-built machines. Excavator-based units offered financial and technical advantages, but their long-term market success will likely depend on future improvements in fuel efficiency, in the face of increasing fuel prices. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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14416 KiB

Open AccessArticle

Suitability of Soil Erosion Models for the Evaluation of Bladed Skid Trail BMPs in the Southern Appalachians

by J. Andrew Vinson, Scott M. Barrett, W. Michael Aust and M. Chad Bolding

Forests 2017, 8(12), 482; https://doi.org/10.3390/f8120482 - 6 Dec 2017

Cited by 18 | Viewed by 6293

Abstract

This project measured soil erosion rates from bladed skid trails in the mountains of Virginia following a timber harvest, and compared measured erosion to four erosion model predictions produced by Universal Soil Loss Equation—Forest (USLE-Forest), Revised Universal Soil Loss Equation, v.2 (RUSLE2), Water [...] Read more.

This project measured soil erosion rates from bladed skid trails in the mountains of Virginia following a timber harvest, and compared measured erosion to four erosion model predictions produced by Universal Soil Loss Equation—Forest (USLE-Forest), Revised Universal Soil Loss Equation, v.2 (RUSLE2), Water Erosion Prediction Project—Road (WEPP-Road) using default files, and WEPP-Road using modified files in order to assess the utility of the models for these conditions. Skid trails were segregated into six blocks where each block had similar trail slopes and soils. Each block contained four skid trail closure treatments: (1) bare soil (Control); (2) residual limbs and tops (Slash); (3) grass seed (Seed); and (4) fertilizer, seed, and straw mulch (Mulch). All treatments had waterbars, the minimum trail closure best management practice (BMP), to provide upslope and downslope borders of experimental units. Site cover characteristics on each experimental unit were collected quarterly as input parameters for erosion models. The suitability of soil erosion models were evaluated based upon statistical summaries, linear relationships with measured erosion rates, Nash-Sutcliffe Model Efficiency, and a nonparametric analysis. Treatments were measured to have erosion rates of 15.2 tonnes ha⁻¹ year⁻¹ (Control), 5.9 tonnes ha⁻¹ year⁻¹ (Seed), 1.1 tonnes ha⁻¹ year⁻¹ (Mulch), and 0.8 tonnes ha⁻¹ year⁻¹ (Slash). It was determined that WEPP-Road: Modified (p-value = 0.643) and USLE-Forest (p-value = 0.307) were the most suitable models given their accuracy; however USLE-Forest may be better for making management decisions given its practicality. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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2031 KiB

Open AccessArticle

Aboveground Biomass Equations for Small Trees of Brutian Pine in Turkey to Facilitate Harvesting and Management

by Mehmet Eker, Krishna P. Poudel and Ramazan Özçelik

Forests 2017, 8(12), 477; https://doi.org/10.3390/f8120477 - 3 Dec 2017

Cited by 16 | Viewed by 5209

Abstract

Brutian pine (Pinus brutia Ten.) is the most widespread conifer species in the Eastern Mediterranean. Aboveground biomass equations for small diameter brutian pine trees are needed for accurate fuel inventory and to assess carbon sequestration potential. In this study, we developed tree [...] Read more.

Brutian pine (Pinus brutia Ten.) is the most widespread conifer species in the Eastern Mediterranean. Aboveground biomass equations for small diameter brutian pine trees are needed for accurate fuel inventory and to assess carbon sequestration potential. In this study, we developed tree biomass models based on 143 brutian pine saplings measured in 11 research plots. Aboveground biomass (AGB) was modeled with a nonlinear mixed effects model which accounted for the variability among plots. The predicted total AGB was then distributed into foliage, branch and stem components. The Beta, Dirichlet, and multinomial logistic regressions were unbiased in their estimates of biomass component proportions. The Dirichlet regression has the advantage of an additive property and does not require non-standard data. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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1788 KiB

Open AccessArticle

Characteristics of Logging Businesses across Virginia’s Diverse Physiographic Regions

by Scott M. Barrett, M. Chad Bolding and John F. Munsell

Forests 2017, 8(12), 468; https://doi.org/10.3390/f8120468 - 28 Nov 2017

Cited by 28 | Viewed by 4331

Abstract

Logging businesses play an important role in implementing forest management plans and delivering the raw material needed by forest products mills. Understanding the characteristics of the logging workforce can help forest managers make better decisions related to harvesting operations. We surveyed logging business [...] Read more.

Logging businesses play an important role in implementing forest management plans and delivering the raw material needed by forest products mills. Understanding the characteristics of the logging workforce can help forest managers make better decisions related to harvesting operations. We surveyed logging business owners across Virginia’s three physiographic regions (Mountains, Piedmont, and Coastal Plain). Overall, logging businesses reported an average production rate of 761.37 t/business/week, but this varied substantially by region, with the highest production rates in the Coastal Plain (1403.55 t/business/week), followed by the Piedmont (824.69 t/business/week) and the Mountains (245.42 t/business/week). Many operations in the Mountains rely primarily on manual felling (66.6% of respondents) and these operations often have lower production rates. Across all regions, 81.7% of reported production came from operations that primarily utilized rubber-tired feller-bunchers for felling. Logging businesses were sorted based on reported production capacity and then divided into three groups (high, medium, and low production) based on total reported production. Across all regions, the majority of reported production was produced by the high production logging businesses. This was highest in the Piedmont, where the high production businesses accounted for 74.8% of total reported production. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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1393 KiB

Open AccessFeature PaperArticle

Influence of Chain Filing, Tree Species and Chain Type on Cross Cutting Efficiency and Health Risk

by Jurij Marenče, Matevž Mihelič and Anton Poje

Forests 2017, 8(12), 464; https://doi.org/10.3390/f8120464 - 24 Nov 2017

Cited by 18 | Viewed by 4965

Abstract

As one of the major parts of the chainsaw, the cutting chain has an important impact on productivity and health risk in motor-manual harvesting. The efficiency of cross cutting and quantity of sawdust produced in relation to different cutting chain settings, chain producers [...] Read more.

As one of the major parts of the chainsaw, the cutting chain has an important impact on productivity and health risk in motor-manual harvesting. The efficiency of cross cutting and quantity of sawdust produced in relation to different cutting chain settings, chain producers and wood species has been measured. The trial was set up to include two tree species (fir and beech) and saw chains from two different producers. The chains were filed at three different top plate filing angles and depth height gauges. All factors were significant in terms of cutting efficiency and wood dust production. The top plate angle recommended by producers proved to be the most efficient, with the smallest quantity of inhalable wood dust. Cutting chain settings can be adapted to the specific requirements of the user; however, safe working practices should be followed. Significant differences between chain producers mean that users should conduct rational decision making when choosing a saw chain. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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2529 KiB

Open AccessArticle

Incidence of Trailer Frame Structure on Driver’s Safety during Log Transportation

by Marco Manzone and Angela Calvo

Forests 2017, 8(11), 456; https://doi.org/10.3390/f8110456 - 18 Nov 2017

Viewed by 4958

Abstract

The frame structure of the trailer may influence both the traction and the tractor-trailer stability, especially along sloped paths. The aim of this research was to analyze a trailer overturning and the strains on the connected tractors (wheeled, or crawled) during log transportation [...] Read more.

The frame structure of the trailer may influence both the traction and the tractor-trailer stability, especially along sloped paths. The aim of this research was to analyze a trailer overturning and the strains on the connected tractors (wheeled, or crawled) during log transportation (loose or tied) along a hillside. Two two-axle trailers were used: tandem and turntable steering. Three types of measurements were carried out during the field tests: (i) the detachment from the ground of the rear upstream wheels (or crawler); (ii) the transversal and longitudinal strains occurring when the trailer overturned (and released the hooking system of the tractor); (iii) the lateral deviation of the rear wheels (or crawler) of the tractor. The study highlighted that the two-axle trailer with turntable steering combined with the crawl tractor gave better results in terms of safety during trailer overturning. In addition, independent of the type of trailer, a tied load was found to be more dangerous than a load restrained only by steel struts, because when overturning, the load forms a single unit with the trailer mass which increases the strains. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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2513 KiB

Open AccessArticle

The Optimum Slash Pile Size for Grinding Operations: Grapple Excavator and Horizontal Grinder Operations Model Based on a Sierra Nevada, California Survey

by Takuyuki Yoshioka, Rin Sakurai, Shohei Kameyama, Koki Inoue and Bruce Hartsough

Forests 2017, 8(11), 442; https://doi.org/10.3390/f8110442 - 15 Nov 2017

Cited by 6 | Viewed by 15106

Abstract

The processing of woody biomass waste piles for use as fuel instead of burning them was investigated. At each landing of slash pile location, a 132 kW grapple excavator was used to transfer the waste piles into a 522 kW horizontal grinder. Economies [...] Read more.

The processing of woody biomass waste piles for use as fuel instead of burning them was investigated. At each landing of slash pile location, a 132 kW grapple excavator was used to transfer the waste piles into a 522 kW horizontal grinder. Economies of scale could be expected when grinding a larger pile, although the efficiency of the loading operation might be diminished. Here, three piles were ground and the operations were time-studied: Small (20 m long × 15 m wide × 4 m high), Medium (30 × 24 × 4 m), and Large (35 × 30 × 4 m) piles. Grinding the Medium pile was found to be the most productive at 30.65 bone dry tons per productive machine hour without delay (BDT/PMH₀), thereby suggesting that there might be an optimum size of slash pile for a grinding operation. Modeling of the excavator and grinder operations was also examined, and the constructed simulation model was observed to well-replicate the actual operations. Based on the modeling, the productivity of grinding at a landing area of 710 m² of slash pile location was estimated to be 31.24 BDT/PMH₀, which was the most productive rate. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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720 KiB

Open AccessArticle

Occupational Safety and Health Concerns in Logging: A Cross-Sectional Assessment in Virginia

by Sunwook Kim, Maury A. Nussbaum, Ashley L. Schoenfisch, Scott M. Barrett, Michael Chad Bolding and Deborah E. Dickerson

Forests 2017, 8(11), 440; https://doi.org/10.3390/f8110440 - 15 Nov 2017

Cited by 14 | Viewed by 4930

Abstract

Increased logging mechanization has helped improve logging safety and health, yet related safety risks and concerns are not well understood. A cross-sectional study was completed among Virginia loggers. Participants (n = 122) completed a self-administered questionnaire focusing on aspects of safety and [...] Read more.

Increased logging mechanization has helped improve logging safety and health, yet related safety risks and concerns are not well understood. A cross-sectional study was completed among Virginia loggers. Participants (n = 122) completed a self-administered questionnaire focusing on aspects of safety and health related to logging equipment. Respondents were at a high risk of workplace injuries, with reported career and 12-month injury prevalences of 51% and 14%, respectively. Further, nearly all (98%) respondents reported experiencing musculoskeletal symptoms. Over half (57.4%) of respondents reported symptoms related to diesel exhaust exposure in their career. Few (15.6%), however, perceived their jobs to be dangerous. Based on the opinions and suggestions of respondents, three priority areas were identified for interventions: struck-by/against hazards, situational awareness (SA) during logging operations, and visibility hazards. To address these hazards, and to have a broader and more substantial positive impact on safety and health, we discuss the need for proactive approaches such as incorporating proximity technologies in a logging machine or personal equipment, and enhancing logging machine design to enhance safety, ergonomics, and SA. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

1060 KiB

Open AccessArticle

Policy Recommendation from Stakeholders to Improve Forest Products Transportation: A Qualitative Study

by Anil Koirala, Anil Raj Kizha and Sandra M. De Urioste-Stone

Forests 2017, 8(11), 434; https://doi.org/10.3390/f8110434 - 12 Nov 2017

Cited by 20 | Viewed by 5793

Abstract

With recently announced federal funding and subsidies to redevelop vacant mills and the communities they were in, the forest products industry in Maine is poised to gain its momentum once again. One of the important components influencing the cost of delivered forest products [...] Read more.

With recently announced federal funding and subsidies to redevelop vacant mills and the communities they were in, the forest products industry in Maine is poised to gain its momentum once again. One of the important components influencing the cost of delivered forest products is transportation. A recent study in the region has shown that the location and availability of markets along with lack of skilled labor force are the major challenges faced by the forest products transportation sector in Maine. This study was focused on developing a management guideline which included various field level options for improving trucking enterprises in Maine. For this, a qualitative research approach utilizing a case study research tradition was employed, with in-depth semi-structured interviews with professionals directly related to the forest products transportation sector used for data generation. Thirteen semi-structured interviews were conducted, with each being audio recorded and later transcribed verbatim. Interview transcriptions were analyzed using NVivo 11. Suggestions, like increasing benefits to drivers and providing training, were proposed for challenges related to manpower shortage, while the marketing of new forest products and adjustment in some state-level policies were proposed for challenges related to the forest products market condition of the state. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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2502 KiB

Open AccessArticle

The Effect of Logging and Strip Cutting on Forest Floor Light Condition and Following Change

by Tomoya Inada, Kaoru Kitajima, Suryo Hardiwinoto and Mamoru Kanzaki

Forests 2017, 8(11), 425; https://doi.org/10.3390/f8110425 - 7 Nov 2017

Cited by 7 | Viewed by 4167

Abstract

We monitored changes in light conditions at a primary forest and two managed forest sites (one with line planting) after reduced-impact logging in Central Kalimantan, Indonesia. We also assessed the effect of the light conditions on seedlings in the planting lines. Hemispherical photographs [...] Read more.

We monitored changes in light conditions at a primary forest and two managed forest sites (one with line planting) after reduced-impact logging in Central Kalimantan, Indonesia. We also assessed the effect of the light conditions on seedlings in the planting lines. Hemispherical photographs were taken over a period of 31 months in three 50 × 50-m quadrats at each site and in three 100-m transects along the planting lines. The location of each photo was categorized according to the corresponding type of disturbance, including skid trails, logging gaps, and planting lines. Following logging, the level of canopy openness (CO) increased at both managed forest sites and did not differ significantly between the two. However, CO was greater in skid trails and logging gaps than in planting lines. After 31 months, the mean level of CO at each managed site had decreased significantly due to the establishment of new seedlings. Correlations between changes in CO and the growth of planted seedlings suggested that growth was inhibited by the invasion of the new species. However, the level of CO along the planting lines was greater than that at other disturbed locations. A high level of CO promoted invasion by new species that colonized the space. Line planting may influence forest dynamics and maintain a high level of CO. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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4725 KiB

Open AccessArticle

Impacts of Early Thinning of a Eucalyptus globulus Labill. Pulplog Plantation in Western Australia on Economic Profitability and Harvester Productivity

by Mauricio Acuna, Martin Strandgard, John Wiedemann and Rick Mitchell

Forests 2017, 8(11), 415; https://doi.org/10.3390/f8110415 - 1 Nov 2017

Cited by 18 | Viewed by 5379

Abstract

The impact of the manipulation of plantation stocking density on individual tree size can affect final harvest costs and machine productivity. This paper investigated the impact of four early-age thinning treatments applied to a Eucalyptus globulus Labill. pulplog plantation in south-west Western Australia [...] Read more.

The impact of the manipulation of plantation stocking density on individual tree size can affect final harvest costs and machine productivity. This paper investigated the impact of four early-age thinning treatments applied to a Eucalyptus globulus Labill. pulplog plantation in south-west Western Australia on economic profitability and harvester productivity. Eighteen sample plots were randomly laid out in the study area. The nominal 700, 500, and 400 stems per hectare (sph) plots were thinned to waste 3.2 years after establishment while the nominal 1000 sph (UTH) plots were left unthinned. The economic analysis showed that all thinning treatments resulted in a lower Land Expectation Value (LEV) and net financial loss over the full rotation at their theoretical optimal rotation age when compared with the unthinned control treatment. Tree growth and form were positively impacted by thinning. However, associated reductions in harvesting costs were less than the value losses resulting from reduced per hectare yield. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessArticle

A Robust Productivity Model for Grapple Yarding in Fast-Growing Tree Plantations

by Riaan Engelbrecht, Andrew McEwan and Raffaele Spinelli

Forests 2017, 8(10), 396; https://doi.org/10.3390/f8100396 - 17 Oct 2017

Cited by 13 | Viewed by 6822

Abstract

New techniques have recently appeared that can extend the advantages of grapple yarding to fast-growing plantations. The most promising technique consists of an excavator-base un-guyed yarder equipped with new radio-controlled grapple carriages, fed by another excavator stationed on the cut-over. This system is [...] Read more.

New techniques have recently appeared that can extend the advantages of grapple yarding to fast-growing plantations. The most promising technique consists of an excavator-base un-guyed yarder equipped with new radio-controlled grapple carriages, fed by another excavator stationed on the cut-over. This system is very productive, avoids in-stand traffic, and removes operators from positions of high risk. This paper presents the results of a long-term study conducted on 12 different teams equipped with the new technology, operating in the fast-growing black wattle (Acacia mangium Willd) plantations of Sarawak, Malaysia. Data were collected continuously for almost 8 months and represented 555 shifts, or over 55,000 cycles—each recorded individually. Production, utilization, and machine availability were estimated, respectively at: 63 m³ per productive machine hour (excluding all delays), 63% and 93%. Regression analysis of experimental data yielded a strong productivity forecast model that was highly significant, accounted for 50% of the total variability in the dataset and was validated with a non-significant error estimated at less than 1%. The figures reported in this study are especially robust, because they were obtained from a long-term study that covered multiple teams and accumulated an exceptionally large number of observations. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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1166 KiB

Open AccessArticle

The Effect of Customer–Contractor Alignment in Forest Harvesting Services on Contractor Profitability and the Risk for Relationship Breakdown

by Mattias Eriksson, Luc LeBel and Ola Lindroos

Forests 2017, 8(10), 360; https://doi.org/10.3390/f8100360 - 25 Sep 2017

Cited by 13 | Viewed by 4690

Abstract

In forest operations, the interface between forest companies and harvesting contractors is of special importance, considering that it is the first link in the forest industry’s supply chains. Supply operations account for a significant share of the final costs of wood products (up [...] Read more.

In forest operations, the interface between forest companies and harvesting contractors is of special importance, considering that it is the first link in the forest industry’s supply chains. Supply operations account for a significant share of the final costs of wood products (up to 50%). This study investigates the effect of customer–contractor alignment on contractors’ profit margins and on the risk for business relationship breakdown. Alignment is empirically measured for a Swedish forest company and 74 of its harvesting contractors, who were monitored during a four-year period. Two measures of alignment are employed: (1) the customer-perceived value of the contractors’ services; and (2) the contractors’ perceived alignment with the forest company expectations. Results indicate that the two measures of alignment are largely independent from each other, and that customer-perceived value affects both contractor profitability and the risk of relationship breakdown. Conflict between the two parties and lack of trust for the customer were found to be common complaints among contractors who ceased working for the studied forest company. Consequently, customer–contractor alignment should be considered a key objective by contractors who strive for business success, and also by forest companies who wish to improve their supply chain performance. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessArticle

Characterizing Rigging Crew Proximity to Hazards on Cable Logging Operations Using GNSS-RF: Effect of GNSS Positioning Error on Worker Safety Status

by Ann M. Wempe and Robert F. Keefe

Forests 2017, 8(10), 357; https://doi.org/10.3390/f8100357 - 23 Sep 2017

Cited by 22 | Viewed by 6534

Abstract

Logging continues to rank among the most lethal occupations in the United States. Though the hazards associated with fatalities are well-documented and safe distances from hazards is a common theme in safety education, positional relationships between workers and hazards have not been quantified [...] Read more.

Logging continues to rank among the most lethal occupations in the United States. Though the hazards associated with fatalities are well-documented and safe distances from hazards is a common theme in safety education, positional relationships between workers and hazards have not been quantified previously. Using GNSS-RF (Global Navigation Satellite System-Radio Frequency) transponders that allow real-time monitoring of personnel, we collected positioning data for rigging crew workers and three common cable logging hazards: a log loader, skyline carriage, and snag. We summarized distances between all ground workers and each hazard on three active operations and estimated the proportion of time crew occupied higher-risk areas, as represented by geofences. We then assessed the extent to which positioning error associated with different stand conditions affected perceived worker safety status by applying error sampled in a separate, controlled field experiment to the operational data. Root mean squared error was estimated at 11.08 m in mature stands and 3.37 m in clearcuts. Simulated error expected for mature stands altered safety status in six of nine treatment combinations, whereas error expected for clearcuts affected only one. Our results show that canopy-associated GNSS error affects real-time geofence safety applications when using single-constellation American Global Positioning System transponders. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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730 KiB

Open AccessArticle

Forestry Best Management Practices Relationships with Aquatic and Riparian Fauna: A Review

by Brooke M. Warrington, W. Michael Aust, Scott M. Barrett, W. Mark Ford, C. Andrew Dolloff, Erik B. Schilling, T. Bently Wigley and M. Chad Bolding

Forests 2017, 8(9), 331; https://doi.org/10.3390/f8090331 - 7 Sep 2017

Cited by 35 | Viewed by 8231

Abstract

Forestry best management practices (BMPs) were developed to minimize water pollution from forestry operations by primarily addressing sediment and sediment transport, which is the leading source of pollution from silviculture. Implementation of water quality BMPs may also benefit riparian and aquatic wildlife, although [...] Read more.

Forestry best management practices (BMPs) were developed to minimize water pollution from forestry operations by primarily addressing sediment and sediment transport, which is the leading source of pollution from silviculture. Implementation of water quality BMPs may also benefit riparian and aquatic wildlife, although wildlife benefits were not driving forces for BMP development. Therefore, we reviewed literature regarding potential contributions of sediment-reducing BMPs to conservation of riparian and aquatic wildlife, while realizing that BMPs also minimize thermal, nutrient, and chemical pollution. We reached five important conclusions: (1) a significant body of research confirms that forestry BMPs contribute to the protection of water quality and riparian forest structure; (2) data-specific relationships between forestry BMPs and reviewed species are limited; (3) forestry BMPs for forest road construction and maintenance, skid trails, stream crossings, and streamside management zones (SMZs) are important particularly for protection of water quality and aquatic species; (4) stream crossings should be carefully selected and installed to minimize sediment inputs and stream channel alterations; and (5) SMZs promote retention of older-age riparian habitat with benefits extending from water bodies to surrounding uplands. Overall, BMPs developed for protection of water quality should benefit a variety of riparian and aquatic species that are sensitive to changes in water quality or forest structure. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessArticle

Can Biomass Quality Be Preserved through Tarping Comminuted Roadside Biomass Piles?

by Suzanne Wetzel, Sylvain Volpe, Janet Damianopoulos and Sally Krigstin

Forests 2017, 8(9), 305; https://doi.org/10.3390/f8090305 - 23 Aug 2017

Cited by 15 | Viewed by 4663

Abstract

Storage conditions play a vital role in maintaining biomass quality as a suitable bioenergy feedstock. Research has shown that biomass undergoes significant changes under different storage conditions and that these may influence its suitability for various biorefining and bioenergy opportunities. This study explores [...] Read more.

Storage conditions play a vital role in maintaining biomass quality as a suitable bioenergy feedstock. Research has shown that biomass undergoes significant changes under different storage conditions and that these may influence its suitability for various biorefining and bioenergy opportunities. This study explores the effects of different tarp covers on the properties of stored-comminuted forest harvest residue from the Great Lakes St. Lawrence Forest. Characteristics of the biomass were evaluated upon harvesting and after one year in storage. The physical state of the different tarps used for pile coverage was monitored onsite. Results indicated that tarp material considerably affects micro-climatic conditions inside piles, yielding variation in the characteristics of stored biomass over the storage period. While plastic based tarps were easier to work with and lasted longer than paper-based tarps, the paper-based tarps were more breathable and resulted in less degradation of biomass. However, the paper-based tarps did not maintain their structural integrity for the full duration of the storage period. Moisture content of original biomass (48.99%) increased to a maximum of 65.25% under plastic cover after 1 year of storage. This negatively influenced the net heating value of the biomass, causing it to decrease from 8.58 MJ/kg to 4.06 MJ/kg. Overall, the use of covers was not considered successful in preserving the original quality of biomass but may enhance its quality for other biorefinery opportunities. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessFeature PaperArticle

How Climate Change Will Affect Forest Composition and Forest Operations in Baden-Württemberg—A GIS-Based Case Study Approach

by Ferréol Berendt, Mathieu Fortin, Dirk Jaeger and Janine Schweier

Forests 2017, 8(8), 298; https://doi.org/10.3390/f8080298 - 16 Aug 2017

Cited by 17 | Viewed by 6464

Abstract

In order to accommodate foreseen climate change in European forests, the following are recommended: (i) to increase the number of tree species and the structural diversity; (ii) to replace unsuitable species by native broadleaved tree species, and (iii) to apply close-to-nature silviculture. The [...] Read more.

In order to accommodate foreseen climate change in European forests, the following are recommended: (i) to increase the number of tree species and the structural diversity; (ii) to replace unsuitable species by native broadleaved tree species, and (iii) to apply close-to-nature silviculture. The state forest department of Baden-Württemberg (BW) currently follows the concept of Forest Development Types (FDTs). However, future climatic conditions will have an impact on these types of forest as well as timber harvesting operations. This Geographic Information System (GIS)-based analysis identified appropriate locations for main FDTs and timber harvesting and extraction methods through the use of species suitability maps, topography, and soil sensitivity data. Based on our findings, the most common FDT in the state forest of BW is expected to be coniferous-beech mixed forests with 29.0% of the total forest area, followed by beech-coniferous (20.5%) and beech-broadleaved (15.4%) mixed forests. Where access for fully mechanized systems is not possible, the main harvesting and extraction methods would be motor manual felling and cable yarding (29.1%). High proportions of large dimensioned trees will require timber extraction using forestry tractors, and these will need to be operated from tractor roads on sensitive soils (23.0%), and from skid trails on insensitive soils (18.4%). Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessArticle

Air Curtain Burners: A Tool for Disposal of Forest Residues

by Eunjai Lee and Han-Sup Han

Forests 2017, 8(8), 296; https://doi.org/10.3390/f8080296 - 14 Aug 2017

Cited by 8 | Viewed by 7624

Abstract

Open pile burning (OPB) forest residues have been limited due to several concerns, including atmospheric pollution, risk of fire spread, and weather conditions restrictions. Air Curtain Burner (ACB) systems could be an alternative to OPB and can avoid some of the negative effects [...] Read more.

Open pile burning (OPB) forest residues have been limited due to several concerns, including atmospheric pollution, risk of fire spread, and weather conditions restrictions. Air Curtain Burner (ACB) systems could be an alternative to OPB and can avoid some of the negative effects that may result from OPB. The main objective was to compare the burning consumption rates and costs of two types of ACB machines, the S-220 and BurnBoss. In addition, we tested a hand-pile burning (HPB) consumption rate for a comparison with BurnBoss unit. The S-220’s burning consumption rates ranged between 5.7 and 6.8 green metric ton (GmT)/scheduled machine hour (SMH) at a cost between US $12.8 and US $10.8/GmT, respectively. Costs were 70% higher when using the BurnBoss unit. Burning residue consumption rates and cost of disposal were considerably different: they were highly dependent on machine size, species, and fuel age of forest residues. Particularly, BurnBoss test burned over 40% more than HPB method and produced clean burn by airflow. The results from this study suggest that ACBs can be a useful tool to dispose of forest residues piled in many forests areas with less concerns of air quality and fire escape risks. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessArticle

Soil Erosion and Forests Biomass as Energy Resource in the Basin of the Oka River in Biscay, Northern Spain

by Esperanza Mateos, José Miguel Edeso and Leyre Ormaetxea

Forests 2017, 8(7), 258; https://doi.org/10.3390/f8070258 - 19 Jul 2017

Cited by 10 | Viewed by 4503

Abstract

The aim of this work has been the development of a methodology for the evaluation of residual forest biomass in Biscay, a province in northern Spain. The study area is located in the Oka river basin, an area of great ecological value qualified [...] Read more.

The aim of this work has been the development of a methodology for the evaluation of residual forest biomass in Biscay, a province in northern Spain. The study area is located in the Oka river basin, an area of great ecological value qualified by UNESCO (United Nations Educational Scientific and Cultural Organization) in 1984 as a Biosphere Reserve. The project tries to determine the potential, available and usable as energy resource, residual forests biomass, after the treatments of forest species in the area. Soil erosion was modeled using the USLE (Universal Soil Loss Equation) and MUSLE (Modified USLE) methods by estimating rainfall erosivity factor (R), the soil erodibility factor (K), the topographic factors (L and S), cropping factor (C), and the conservation practice factor (P). By means of these models, it will be possible to determine the current soil erosion rate and its potential evolution due to different forest treatments. Soil erodibility, slope of the terrain and the loss of SOC (Soil Organic Carbon) were the restrictive indicators for the bioenergy use of forest biomass, taking into account principles of sustainability. The amount of residual forestry biomass useable for energy purposes has been estimated at 4858.23 Mg year⁻¹. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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Open AccessArticle

Deadwood Decay in a Burnt Mediterranean Pine Reforestation

by Carlos R. Molinas-González, Jorge Castro and Alexandro B. Leverkus

Forests 2017, 8(5), 158; https://doi.org/10.3390/f8050158 - 8 May 2017

Cited by 10 | Viewed by 5293

Abstract

Dead wood remaining after wildfires represents a biological legacy for forest regeneration, and its decay is both cause and consequence of a large set of ecological processes. However, the rate of wood decomposition after fires is still poorly understood, particularly for Mediterranean-type ecosystems. [...] Read more.

Dead wood remaining after wildfires represents a biological legacy for forest regeneration, and its decay is both cause and consequence of a large set of ecological processes. However, the rate of wood decomposition after fires is still poorly understood, particularly for Mediterranean-type ecosystems. In this study, we analyzed deadwood decomposition following a wildfire in a Mediterranean pine plantation in the Sierra Nevada Natural and National Park (southeast Spain). Three plots were established over an elevational/species gradient spanning from 1477 to 2053 m above sea level, in which burnt logs of three species of pines were experimentally laid out and wood densities were estimated five times over ten years. The logs lost an overall 23% of their density, although this value ranged from an average 11% at the highest-elevation plot (dominated by Pinus sylvestris) to 32% at an intermediate elevation (with P. nigra). Contrary to studies in other climates, large-diameter logs decomposed faster than small-diameter logs. Our results provide one of the longest time series for wood decomposition in Mediterranean ecosystems and suggest that this process provides spatial variability in the post-fire ecosystem at the scale of stands due to variable speeds of decay. Common management practices such as salvage logging diminish burnt wood and influence the rich ecological processes related to its decay. Full article

(This article belongs to the Special Issue Forest Operations, Engineering and Management)

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