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The prominent objective of present study is to develop an ef- ficient stochastic framework for availability evaluation of harvesting system (HS) using the concept of partial failure of subsystems. A harvesting system is very complex structure configured with four subsystems in series structure. The failure and repair laws of all subsystems are exponentially distributed. The sufficient repair facility available with system and harvesting system work as new after repair. Markovian birth-death methodology is opted for development of Chapman-Kolmogorov differential-difference equations of proposed stochastic framework. The steady state availability of HS system is derived for a particular case. Later, an effort is made to predict the optimal availability and respective optimal parameters of subsystems using metaheuristics algorithms. It is revealed that HS can attain optimal limit of availability 0.9999967 at population size 5 after 25 iterations. This study adds to the body of knowledge about harvesting systems by providing an all-encompassing viewpoint on availability optimization. The study's findings can be utilized in designing reliable harvesting systems. The proposed methodology can be used in other similar kind of mechanical systems. [ABSTRACT FROM AUTHOR]

With the aim of investigating the effect of bruising and its development during the postharvest time, olive fruits (Frantoio and Moraiolo), manually and mechanically harvested, were stored in climatic chambers at two different temperatures (5 °C and 18 °C) for five days. Visual observations highlighted changes in the olive peel with discoloration in the damaged areas and tissue bruising. Olive fruit polyphenols, volatile organic compounds (VOCs) and other oil quality parameters (phenolic content, free acidity and peroxide index) and sensory assessment were evaluated. Analyses were carried out on fruits and experimental extra virgin oils at harvesting and after 5 days of fruit storage. The results highlight that low-temperature storage (5 °C for 5 days) may contribute to the maintenance of high olive oil quality, and the quality of olives stored at room temperature drastically decreases after 5 days of storage. Moreover, mechanical harvesting, compared to manual harvesting, does not seem to affect the final oil quality, at least at harvesting, but seems to determine differences in the long-term storage period. Finally, the samples stored at 18 °C showed a quality deterioration with the development of sensorial defects. [ABSTRACT FROM AUTHOR]

Despite similarly steep terrain, the productivity of forest harvesting operations in Japan is lower than in Central Europe. Harvesting systems in Japan are typically characterized by the four production processes of felling, yarding, processing, and forwarding, whereas in Central Europe they have mostly been reduced to just two through the use of a PTY (Processor Tower Yarder). This study investigated the number of production processes as a reason for the relatively lower productivity of forest harvesting in Japan using the Combined Machine Productivity (CMP) and Combined Labor Productivity (CLP) indices. The CMP and CLP were 1.81 m3/h and 0.45 m3/worker/h, respectively, for a parallel production model based on a typical Japanese forest harvesting system in Japan. The CMP and CLP values were improved to 2.51 m3/h and 0.63 m3/worker/h, respectively, when the forwarding process was removed from the model. The CMP and CLP values were further improved to 3.04 m3/h and 0.76 m3/worker/h, respectively, when yarding and processing were integrated into a single process. Reducing the number of the production processes can therefore improve the productivity of forest harvesting operations in Japan. [ABSTRACT FROM AUTHOR]

This study describes the hypothetical approach to system design to collect and store electrical energy present in a flash of lightning. The system's operations include the attraction and handling of the electrical charge obtained from lightning flashes. Performance differences arise from three different dielectric materials (rutile, mica and quartz) and the results define the estimated response of the storage system, including charge storage. All the results in this article were obtained through simulation or demonstrated mathematically showing the estimated outcomes of the system. The findings demonstrate that each dielectric material has its own advantages and disadvantages that influence the efficiency of the storage system. Through analysing the distinction of the three materials, it is observed that mica is the most suitable dielectric material, as it has the greatest dielectric strength, which is the main factor in the handling of charge. [ABSTRACT FROM AUTHOR]

With the aim of investigating the effect of bruising and its development during the postharvest time, olive fruits (Frantoio and Moraiolo), manually and mechanically harvested, were stored in climatic chambers at two different temperatures (5 °C and 18 °C) for five days. Visual observations highlighted changes in the olive peel with discoloration in the damaged areas and tissue bruising. Olive fruit polyphenols, volatile organic compounds (VOCs) and other oil quality parameters (phenolic content, free acidity and peroxide index) and sensory assessment were evaluated. Analyses were carried out on fruits and experimental extra virgin oils at harvesting and after 5 days of fruit storage. The results highlight that low-temperature storage (5 °C for 5 days) may contribute to the maintenance of high olive oil quality, and the quality of olives stored at room temperature drastically decreases after 5 days of storage. Moreover, mechanical harvesting, compared to manual harvesting, does not seem to affect the final oil quality, at least at harvesting, but seems to determine differences in the long-term storage period. Finally, the samples stored at 18 °C showed a quality deterioration with the development of sensorial defects.

The cooling of olives stored in containers with a capacity of 400 kg risk accumulation of respiration heat and subsequent fruit deterioration. Pre-cooling the fruit to 5 °C before cold storage was studied as a possible solution to overcome this obstacle. The fruit temperature within the containers was recorded daily for 14 days and oil was extracted at days 0, 4, 8, and 14. A second experiment evaluated a rapid pre-cooling procedure at -18 °C for 3 min. No significant alterations at the level of the examined parameters were recorded. The internal temperature of the control container declined and stabilized at around 12 °C. The temperature of the pre-cooled fruit increased to up to 8 °C. The examined parameters showed no significant alterations in either experiment and the rapid pre-cooling treatment did not lead to any visible ‘chill injuries’. A pre-cooling treatment at 5 °C was successfully introduced at the farm of a small producer.

Globally, almost 2 billion cubic meters of industrial roundwood are harvested yearly. Two of the most common methods of harvest and extraction are cut-to-length (CTL) and full-tree or tree-length (FT/TL). The aim of this study was to compile data on annual volumes of industrial roundwood harvested by the main methods in forestry countries. To quantify the effect of potential explanatory variables, the data were subjected to linear regression analysis, using shares of roundwood volumes harvested by fully mechanized CTL and/or FT/TL as response variables. Generally, high diesel price and Gross Domestic Product appear to favor CTL, while high shares of steep terrain (>20°) in forest land decrease the leve l of both mechanization and CTL, and low Social Security Rate (SSR) favor FT/TL. Two models were created for CTL, one with an R2 of 0.64 and another more complex with an R2 of 0.75. A separate model for mechanization (CTL and FT/TL together) showed an R2 0.57. The CTL models could potentially be used to predict shares of roundwood volumes harvested by CTL in countries not included in this study. Predictions for countries with large harvested volumes, e.g. China and India, are presented here, but they require validation, as does the model's applicability for countries with small harvested volumes. Countries with less than 10% of steep slope forests are almost exclusively mechanized according to the model. For FT/TL, the proposed model is probably not sufficiently robust for prediction, but it highlights SSR as one important explanatory variable. [ABSTRACT FROM AUTHOR]

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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. [ABSTRACT FROM AUTHOR]

BACKGROUND: In Europe mulberry cultivation is attracting growing interest for the valuable nutraceutical properties of its fruit; however, mulberry orchards specialized in fruit production only are not very common, therefore an adequate harvesting technique has not been developed. OBJECTIVE: The aim of this work was to evaluate an innovative harvesting system in terms of efficiency and labour required, and to monitor fruit losses. METHODS: Harvesting operations were recorded during inspections to the field during the fruit ripening season; chemical assessment on fruit quality and mechanical tests on the detachment force of fruits at different ripening stages were carried out. RESULTS: We described the structure and functions of the innovative system, its harvesting capacity (kg h–1) in comparison to traditional methods, the related losses, and the quality of collected fruits. CONCLUSIONS: The innovative harvesting system requires a minimum of four workers, but it results in a two to three-fold increase of the hourly productivity per person. Furthermore, it is constructionally and functionally very simple and it does not require important initial or maintenance investments. Overall the system can save labour costs and contribute to spreading of moriculture for fruit production. [ABSTRACT FROM AUTHOR]

Pruning residues could represent an important biomass resources for energy production. Only in Italy it has been estimated that an annual quantity of biomass of over 2600 kt of dry matter could be obtained from olive residues. Several machines developed for pruning harvesting are available in the market, most of which are tractor-driven, while limited knowledge is available on performance, quality of work and costs of harvesting logistics based on stationary chippers. The aim of the present paper is to analyze machine performance of a forestry stationary chipper applied to pruning harvesting for what concerns work productivity, quality of the comminuted product and harvesting operating costs. This system is actually applied by Fiusis Company, an Italian enterprise which manages a biomass power plant exclusively powered by olive trees’ pruning residues, and it has never been analyzed in literature. The results obtained showed consistent work productivity, which resulted the highest ever found in olive pruning harvesting systems and equal to 5.23 ± 0.81 tdm·h−1. This high work productivity allowed also to obtain a little economic gain from a matter, which is actually considered a problem for olive groves’ owners and not a potential source of income. In particular, the use of a stationary chipper seemed very efficient in olive groves with a consistent amount of wooden residues to be processed and with big branches not harvestable by the most common towed pruning harvester. In addition, the stationary chipper has the advantage of avoiding the preliminary raking operation, which results in reduced costs for the farmer.

Forest industry has a direct impact on natural environment, therefore, when setting technological requirements for forest machines an engineer should take into account the environmental implication of future operations. This problem is actual and still unsolved, mostly due to limited knowledge on quantitative estimation methods related to the evaluation of environmental impact. Hence, in this study we made a simulation of forest operations technology enhancement. The aim was to increase the harvesting system output up to the leading machine capacity level to decrease the harvesting time. Using the simulating analysis, this study implements the numerical estimation of impact caused by harvesting machines on the forest ecosystems. In particular, our results indicate that the absolute reduction of carbon oxide (CO) as percentage of machines' emission during the time was 8 to 21% depending on the yearly harvested volume. [ABSTRACT FROM AUTHOR]

This study took a Life Cycle Assessment (LCA) perspective to model a total of twenty forest supply chains, from seedling production to forest biomass delivery to industry. Four scenarios were analyzed, two in Sweden and two in Canada. Resource and energy consumption, and emissions to air, water and soil of conventional and biomass dedicated supply chains were evaluated and compared. The Swedish supply chains showed a better environmental profile, on average, per oven dry tonne (ODt) than the Canadian ones in the regions studied. In terms of climate change potential the Swedish biomass dedicated supply chains generated 48.8 kg CO 2 -eq, 13%, 30% and 38% lower than Swedish conventional, Canadian biomass dedicated and Canadian conventional supply chains, respectively. Sawlogs from final felling in the Swedish biomass dedicated supply chains generated 34.2 kg CO 2 -eq, the lowest emissions within the roundwood assortments. Concerning the forest fuel assortments in form of wood chips, pulpwood from final felling in the Swedish conventional supply chains, and stump core and long tops from final felling in the Swedish biomass dedicated supply chains generated the lowest emissions: 48.9 kg CO 2 -eq, 52.3 Kg CO 2 -eq and 57.8 kg CO 2 -eq respectively. Transport from forest to industry, harvesting, extraction, chipping, and crushing were identified as hotspots in the forest supply chains. Forwarding versus skidding, chipping and transportation were the processes that differed the most between countries. In both countries, when the supply chains were biomass dedicated the environmental impacts per ODt were lower than in the conventional supply chains. Therefore, integrating forest fuel supply with industrial wood harvesting has the potential to reduce emissions. [ABSTRACT FROM AUTHOR]

Commercial thinning (CT) is an important silvicultural practice in the northeastern United States. Relatively little is known, however, about the interaction of harvest system and treatment (removal intensity or timing of entry) on the overall profitability of CT. To address this question, 10-year measurements from a controlled CT experiment across six sites in Maine were used to project the long-term effect of removal intensity (33% and 50% relative density reduction) and timing of entry (no delay, 5-year delay, 10-year delay) on ( i) maximum net present value (NPV), ( ii) timing of maximum NPV, and ( iii) the effect of three harvesting systems (cut-to-length, whole-tree, hybrid systems) on maximum NPV. A regional growth and yield model was used to project individual-tree growth and mortality into the future. Harvest costs for the harvesting systems were estimated using regional cycle-time equations. No difference was found in maximum NPV between the CT and non-CT areas or the timing of CT entry. Stand age at time of maximum NPV differed between delays but not between the two removal intensities. Our results indicate that there is no economic benefit in delaying a CT or removing more volume at the time of thinning for the range of stand conditions evaluated. [ABSTRACT FROM AUTHOR]

In this study, we report efficiencies of light capture and biomass yield of festulolium and tall fescue cultivated on a riparian fen in Denmark under different harvesting managements. Green biomass targeted for biogas production was harvested either as two cuts (2C) or three cuts (3C) in a year. Three different timings of the first cut in the 2C systems were included as early (2C-early), middle (2C-mid) and late (2C-late) cuts corresponding to pre-heading, inflorescence emergence and flowering stages, respectively. The fraction of intercepted photosynthetically active radiation (f PAR ) was derived from the canopy reflectance measured on 61 dates throughout a year, and cumulative interception of PAR (IPAR) and radiation use efficiency (RUE) was calculated. The dynamics of f PAR and biomass accumulations was similar for both crops before the first cuts in all managements. Festulolium f PAR in 2C-early and 2C-mid managements declined faster than in 2C-late and 3C managements in the second growth period and thus growing period IPAR of 2C-early and 2C-mid declined by 8% as compared to 3C management where IPAR was 925 MJ m −2 . Annual festulolium dry matter (DM) yield in 2C-early and 2C-mid managements (average 14.1 Mg DM ha −1 ) decreased by 22% compared to 3C management (18.2 Mg DM ha −1 ). The highest and the lowest RUE of festulolium were observed in 3C and 2C-mid managements as 1.97 and 1.59 g MJ −1 , respectively. For tall fescue f PAR declined rather slowly in the second growing period in all 2C managements, which contributed to similar IPAR (908–919 MJ m −2 ), total biomass yield (16.4–18.8 Mg DM ha −1 yr −1 ) and RUE (1.80–2.07 g MJ −1 ) for all managements. Whereas both crops were highly productive under both 3C management and 2C management with first harvest after flowering (i.e., 2C-late), the 2C-late strategy is recommended as the least intensive of the two management systems. [ABSTRACT FROM AUTHOR]

The use of marginal land for Short Rotation Coppice (SRC) might contribute to a sustainable energy supply in future. We assessed the environmental impacts of common production chains for manufacturing wood chips from SRC with poplar, including all the processes necessary to produce and deliver chips to a plant gate in 50 km distance from the field site (“cradle-to-plant gate”). To do so, we carried out a Life Cycle Analysis (LCA) including upstream processes. Results showed clearly that the specific environmental impacts were mainly caused by the processes “harvesting” and “transport”. Using a cut-and-chip harvesting system with a forage harvester generated low impacts during harvesting because of its high productivity. Using a cut-and-storage harvesting system with a whole rod harvester, however, didn't require accompanying tractor-trailer units during harvesting and allowed storing stems before chipping thereby, reducing the moisture content to approximately 30%. Consequently, the transport to the plant caused significantly lower environmental impacts at the same distance (50 km) which lead to a better result when looking at the overall production chain (26 vs. 36 kg CO 2 -eq Mg dm −1 ). Respective energy output to energy input ratios were 23:1 and 26:1. We also analysed the impacts of irrigation and fertigation as they might be options to increase biomass yield. Both treatments lead to considerably increased environmental impacts in all analysed categories which might be balanced only if the biomass yields increase substantially; an effect which could not be verified within the current study. [ABSTRACT FROM AUTHOR]

To utilize timber and forest biomass resources for bioenergy, technically feasible and economically viable timber and forest biomass resources should be estimated accurately considering their long-term availability. This study focuses on five prefectures, namely, Aomori, Iwate, Miyagi, Akita, and Yamagata, and considers trade between these prefectures. The annual availability of timber and forest biomass resources, such as small-diameter or defect stem logs, rather than logging residues in Japan was estimated as supply potential from profitable forests where expected revenues surpassed all costs, from planting to final harvest. As a result, the supply potential and annual availability of timber were estimated at 11,388,960 m3/year and 1,631,624 m3/year, whereas those of forest biomass resources were estimated at 2,277,792 m3/year and 326,325 m3/year, respectively. Therefore, the rate of annual availability to supply potential was 14.3%. Since timber production and wood chip usage from thinned woods and logging residues in 2018 were 4,667,000 m3/year and 889,600 m3/year, the rates of annual availability for timber and forest biomass resources to those values were 35.0% and 36.7%, respectively. Furthermore, the demand was estimated at 951,740 m3/year from 100,000 m3/year with a generation capacity of 5 MW. The rate of forest biomass resource availability to demand was 34.2%. A thinning subsidy was provided for operational site areas larger than 5 ha in Japan. The rates from subcompartments and aggregated forests with a thinning subsidy increased to 91.4% and 190.3%, respectively. Thus, the estimated availability from aggregated forests with a thinning subsidy met the demand sufficiently in this region. [ABSTRACT FROM AUTHOR]

• Timber and forest biomass resource availability estimated with inter-prefectural trade. • Appropriate harvesting system determined based on topography. • CTL has highest productivity and lowest cost; annual availability is highest under CTL. • Thinning and additional regeneration subsidies enhance availability. • Subsidy plays an important role in the supply of timber and forest biomass resources. This study estimates the supply potential and annual availability of timber and forest biomass resources under profitable forest management in Japan. It focuses on four prefectures, namely, Fukushima, Ibaraki, Tochigi, and Gunma, and considers the trade between these prefectures. Production forests were extracted as subcompartments where the expected revenues surpassed all costs, from planting to final harvest. To estimate harvesting costs, appropriate harvesting systems were determined according to each prefecture's topographical features. The log markets and woody biomass power generation plants were assumed to be the destinations for timber and forest biomass resources. Annual availability from the Cut-To-Length (CTL) system, consisting of the use of harvesters and forwarders, accounted for 58 % of the total availability, even though the supply potential from CTL was only 15 %; this is because CTL is the most productive and least expensive harvesting system. Then, the effects of subsidies on availability are examined. Availability under an additional regeneration subsidy meets almost the entire current demand in this region. Furthermore, availability with a thinning subsidy can meet the forecasted future demand in this region, while availability with both thinning and additional regeneration subsidies can meet future demand in all prefectures analyzed in the present study. Thus, subsidies play an important role in the profitability of forestry operations as well as the supply of timber and forest biomass resources in Japan. [ABSTRACT FROM AUTHOR]

Pruning residues could represent an important biomass resources for energy production. Only in Italy it has been estimated that an annual quantity of biomass of over 2600 kt of dry matter could be obtained from olive residues. Several machines developed for pruning harvesting are available in the market, most of which are tractor-driven, while limited knowledge is available on performance, quality of work and costs of harvesting logistics based on stationary chippers. The aim of the present paper is to analyze machine performance of a forestry stationary chipper applied to pruning harvesting for what concerns work productivity, quality of the comminuted product and harvesting operating costs. This system is actually applied by Fiusis Company, an Italian enterprise which manages a biomass power plant exclusively powered by olive trees' pruning residues, and it has never been analyzed in literature. The results obtained showed consistent work productivity, which resulted the highest ever found in olive pruning harvesting systems and equal to 5.23 ± 0.81 tdm·h−1. This high work productivity allowed also to obtain a little economic gain from a matter, which is actually considered a problem for olive groves' owners and not a potential source of income. In particular, the use of a stationary chipper seemed very efficient in olive groves with a consistent amount of wooden residues to be processed and with big branches not harvestable by the most common towed pruning harvester. In addition, the stationary chipper has the advantage of avoiding the preliminary raking operation, which results in reduced costs for the farmer. [ABSTRACT FROM AUTHOR]