past present and future of industrial plantation forestry and implication on future timber harvesting technology

Plantation forests are established, and expanding, to satisfy increasing global demand for timber products. Shifting societal values, such as safety, productivity, environmental, quality and social are influencing the plantation forestry sector. This is primarily driven through an ever increasing world population, which in turn influences the way nations view the value systems by which they live. More people require more resources—also forest products. Also, the availability of information is influencing the pace of technological development. These changes could result in a difference in the management of plantations that could affect the forest engineering systems of the future. This review aimed to summarize the current status of plantation forests; summarize future developments and possible scenarios in forest plantation management for the various products; and assess whether these developments in a plantation environment could affect the harvesting systems used. Factors influencing the form of plantations include the type and nature of the plantation owner; the change in demand for different and new forest products; climate change factors, including the use of biomass for energy, carbon sequestration and trading; ecosystem services and other products and services; and sustainability certification of forest management. The impact and influence of these factors were summarised into a series of key drivers that will influence the technology used in harvesting machines, as well as the choice of harvesting machines, systems and methods. These drivers were the effect of variations in tree size, the expansion of plantation areas onto more difficult terrain, diversity in plantation design, increased attention towards site impacts and the increased use of biomass for energy. Specific information is provided regarding how the harvesting systems could be affected

Factors affecting the productivity and work quality of chain flail delimbing and debarking

Chain flail delimbing and debarking may improve value recovery from small tree harvests, without renouncing the benefits of multi-tree processing. The technology is mature and capable of excellent performance, which has been documented in many benchmark studies. This paper offers new insights into the relationship between the performance of chain flail delimbing and debarking and such factors as tree volume, load volume, tree form and bark-wood bond strength (BWBS). The study was conducted in Chile, during the commercial harvesting of a Eucalyptus globulus Labill. plantation. In an observational study, researchers collected production data from over 780 work cycles, and work quality data from over 1000 individual trees. The analysis of these data shows that productivity is affected primarily by load volume. Work quality is affected by BWBS and by the number of trees in a load. Work quality degrades with increasing BWBS and tree number, since more trees tend to shield each other. Tree form has no effect on either productivity or work quality. Regression and probability functions are provided, and can be used for predictive purposes when trying to optimize current operations or to prospect the introduction of chain flail technology to new work environments.http://www.silvafennica.fiam2017Plant Production and Soil Scienc

A forecast of future silviculture re-establishment technologies in plantation forestry

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Productivity and cost analysis of semi-mechanised and mechanised systems on the Viphya forest plantations in Malawi

At least 200 000 m3 of timber is harvested annually using semi-mechanised harvesting systems on the Viphya forest plantations in Malawi. Although these systems have long been used on the Viphya, no investigation on their productivity has so far been reported. Additionally, the absence of localised productivity analyses in Malawi has created a paucity of information on appropriate timber harvesting systems for production maximisation and cost minimisation. The objective of this study was to compare the production rates and operational costs of chainsaw/grapple skidder (semi-mechanised) and feller-buncher/grapple skidder (mechanised) harvesting systems in order to determine the economic feasibility of mechanised systems in the Viphya forest plantations. The study was conducted in Pinus kesiya compartments at the Kalungulu and Champhoyo forest stations of the Viphya forest plantations. A work study approach was followed to capture harvesting time and volume data for the semi-mechanised system. Secondary work study data were used to simulate productivity of the mechanised system on similar compartment conditions. A timber-harvesting costing model was used to analyse the results. The study showed that the simulated mechanised system was associated with lower operating costs and inventories with higher production rates than the semi-mechanised system. The cost marginal difference was US$0.89 m−3. It was therefore established that migration to mechanised systems could optimise timber harvesting productivity on the Viphya in future, if optimal volumes are available to ensure the efficient application of the mechanised harvesting system.Mzuzu University and the SAFCOL Forest Chair of University of Pretoria, Barloworld Equipment (Isando) and John Deere (Nelspruit)http://www.tandfonline.com/loi/tsfs202015-08-30hb201

Operator work-related musculoskeletal disorders during forwarding operations in South Africa : an ergonomic assessment

Forest machine operators are still experiencing Work-Related Musculoskeletal Disorders (WMSD’s) despite extensive mechanisation and modernisation of harvesting systems. However paucity of local ergonomics research and technology transfer problems may affect the use of mechanised systems in South Africa. Consequently this study was a field- based ergonomic assessment of local forwarding operations. PG Bison’s North East Cape Forests (NECF), Eastern Cape operations and Komatiland Forests (KLF), Mpumalanga operations were studied. The main aim of the study was to carry out an ergonomic assessment on local forwarder operator tasks, using Tigercat 1055 forwarders. The study specifically assessed WMSD prevalence and risk factors, investigated the frequency of awkward head postures and evaluated work organisation. A modified Nordic musculoskeletal questionnaire was used to survey WMSD prevalence and work organisation factors. Operators reported hourly, localised work-related musculoskeletal discomfort experienced during the shift. A video camera mounted in the cab was used to capture footage of awkward head postures. The video footage was also used for the WMSD risk assessment using the Health and Safety Executive (HSG60) upper limb disorder assessment worksheets. Operators reported having experienced WMSD’s during the last 12 months mainly in the lower back, neck, shoulders and upper back. The studied operators reported lower repetition strain symptoms and higher lower back disorders than in previous studies. Twenty three percent of the awkward head postures adopted were extreme. The study results support the assertion that causal pathways of WMSD’s are complex and multifactorial. Repetition, awkward head posture, duration of exposure, vibration, psychological factors and individual differences were identified as the main WMSD risk factors.York Timbers.http://www.tandfonline.com/loi/tsfs202017-02-28hb2016Plant Production and Soil Scienc

Current status of technology-use for plantation re-establishment in South Africa

Plantation re-establishment is a key component of silviculture as it deals with the creation of a suitable environment when planting or seeding a stand. Re-establishment practices include slash management, site preparation, marking and preparation of a planting position, planting, fertilisation and vegetation management. Over the past decade, there has been a shift towards mechanising re-establishment activities primarily due to labour challenges such as: aging rural workforce; increasing labour costs; high labour turnover; problematic health issues leading to lower productivity; inconsistent work quality by manual labour; and poor ergonomic practices. A survey was conducted to assess and gauge the level of mechanisation within these re-establishment practices in South Africa. Responses to an e-mail questionnaire were received from 43 contractors and 11 grower companies from within the different provinces where commercial forestry is practiced in South Africa. The survey, a first of its kind, was designed and administered following the techniques used in conducting the Forest Engineering technical survey. Descriptive and inferential statistics were used to analyse the data. The results showed that the total area re-planted by respondent contractors and grower companies was ± 36 923 ha–1 per year. The predominant activities conducted prior to planting comprised: burning (78%); marking a planting position using the baseline method (71%); preparation of a planting position using a road pick (57%) and pre-plant chemical weeding with a knapsack (70%). Furthermore, 45% of planting and 77% of blanking operations were carried out manually with a trowel. Post planting activities such as fertilizing and weeding were carried out through manual spot application of fertiliser (61%) and herbicide application with a knapsack (43%). Overall, the results indicated that typical re-establishment activities are still dominated by manual methods. This study is a baseline for future, periodic surveys that can be conducted to analyse trends and identify areas for improvement in re-establishment activities in South Africa.The Nelson Mandela University and FP&M SETA.https://www.tandfonline.com/loi/tsfs202021-11-18hj2021Plant Production and Soil Scienc

Sustainable forest operations (SFO) : a new paradigm in a changing world and climate

The effective implementation of sustainable forest management depends largely on carrying out forest operations in a sustainable manner. Climate change, as well as the increasing demand for forest products, requires a re-thinking of forest operations in terms of sustainability. In this context, it is important to understand the major driving factors for the future development of forest operations that promote economic, environmental and social well-being. The main objective of this paper is to identify important issues concerning forest operations and to propose a new paradigm towards sustainability in a changing climate, work and environmental conditions. Previously developed concepts of forest operations are reviewed, and a newly developed concept – Sustainable Forest Operations (SFO), is presented. Five key performance areas to ensure the sustainability of forest operations include: (i) environment; (ii) ergonomics; (iii) economics; (iv) quality optimization of products and production; and (v) people and society. Practical field examples are presented to demonstrate how these five interconnected principles are relevant to achieving sustainability, namely profit and wood quality maximization, ecological benefits, climate change mitigation, carbon sequestration, and forest workers' health and safety. The new concept of SFO provides integrated perspectives and approaches to effectively address ongoing and foreseeable challenges the global forest communities face, while balancing forest operations performance across economic, environmental and social sustainability. In this new concept, we emphasize the role of wood as a renewable and environmentally friendly material, and forest workers' safety and utilization efficiency and waste management as additional key elements of sustainability.http://www.elsevier.com/locate/scitotenv2019-09-01hj2018Plant Production and Soil Scienc

Validation of the Bath CRPS Body Perception Disturbance Scale

The Bath Complex Regional Pain Syndrome Body Perception Disturbance Scale ("B-CRPS-BPDS") measures alterations in body perception. We assessed its internal consistency, known group validity, construct validity, and associations with demographic and clinical characteristics. We also evaluated changes in, and baseline predictors of B-CRPS-BPDS scores at follow-up. We included people with CRPS (N = 114) and pain-free controls (N = 69). People with CRPS obtained higher scores than pain-free controls on all B-CRPS-BPDS items, except the item on attention. Because this item also had an insufficient corrected item-total correlation, we propose a revised B-CRPS-BPDS (r-B-CRPS-BPDS) excluding this item. The internal consistency of the r-B-CRPS-BPDS was good. The r-B-CRPS-BPDS showed a large positive relationship with "motor neglect-like symptoms", indicating good construct validity. The r-B-CRPS-BPDS showed positive relationships with pain intensity, fear of movement, depression, and upper limb disability. There were no independent relationships with handedness, affected side, affected limb, disease duration, CRPS severity score, tension, anger, fatigue, confusion, and vigour. Finally, r-B-CRPS-BPDS scores did not consistently change over time. Our results demonstrate the utility of the r-B-CRPS-BPDS for measuring body perception disturbances in CRPS. PERSPECTIVE: This article evaluates the validity of the Bath Complex Regional Pain Syndrome Body Perception Disturbance Scale ("B-CRPS-BPDS") in CRPS, and assesses relationships with demographic and clinical variables. The proposed revised B-CRPS-BPDS appears to be a valid measure of body perception disturbances in CRPS

On the nitrogen-induced lattice expansion of a non-stainless austenitic steel, Invar 36®, under triode plasma nitriding

Chromium, as a strong nitride-forming element, is widely regarded to be an “essential” ingredient for the formation of a nitrogen-expanded lattice in thermochemical nitrogen diffusion treatments of austenitic (stainless) steels. In this article, a proprietary “chrome-free” austenitic iron-nickel alloy, Invar® 36 (Fe-36Ni, in wt pct), is characterized after triode plasma nitriding (TPN) treatments at 400 °C to 450 °C and compared with a “stainless” austenitic counterpart RA 330® (Fe-19Cr-35Ni, in wt pct) treated under equivalent nitriding conditions. Cr does indeed appear to play a pivotal role in colossal nitrogen supersaturation (and hence anisotropic lattice expansion and superior surface hardening) of austenitic steel under low-temperature (≤ 450 °C) nitrogen diffusion. Nevertheless, this work reveals that nitrogen-induced lattice expansion occurs below the nitride-containing surface layer in Invar 36 alloy after TPN treatment, implying that Cr is not a necessity for the nitrogen-interstitial induced lattice expansion phenomenon to occur, also suggesting another type of γN