Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1294
A. Solgi, E. Zenner, R. Naghdi, Ali Masumian, Ramin Shoja, Frashad Keivan Behjou
Forest operations can lead to increased runoff and soil loss on roads and skid trails. The aim of this study was to evaluate the effectiveness of two erosion control treatments applied to different segments of skid trails following six natural rainfall events. A total of 162 plots 10 m long by 4 m wide were established in a Hyrcanian deciduous forest to assess soil runoff and soil loss following ground-based harvesting traffic. The experimental setup consisted of three levels of traffic intensity (three, eight and 16 skidder passes), two levels of slope gradient (≤20% and >20%), three classes of curvature (narrow = high deflection angle, 60°–70°; wide = low deflection angle, 110°–130°, and straight trail segments), and three classes of mulch cover (bare soil, sawdust cover, and rice straw cover). Each treatment combination was replicated three times, yielding 972 soil samples. The average surface runoff volume and soil loss differed significantly between the switchbacks and the straight trail segments and depended strongly on the degree of curvature, with severity of adverse effects increasing with curve tightness. Mulch cover treatments had a significant ameliorating effect on the surface runoff volume and soil loss throughout the skid trail. The average runoff and soil loss from the skid trails treated with sawdust cover (SC) (0.24 g m-2 (mm) and 0.49 g m-2, respectively) were lower than on trails covered with rice straw (RSC) (0.45 g m-2 and 1.19 g m-2, respectively), which were, in turn lower than on untreated bare soil (BS) trail segments (0.70 g m-2 and 2.31 g m-2, respectively). Surface runoff volume was significantly positively correlated with soil loss and both were positively correlated with dry bulk density and rut depth and negatively correlated with litter mass, total porosity, and macroporosity. Surface cover is a successful measure for controlling erosion losses following skidding disturbances, particularly in the switchback curves of trails on steep slopes where erosion potential is high.
森林作业可能导致道路和滑道的径流和土壤流失增加。本研究的目的是评估在六次自然降雨事件后，两种侵蚀控制措施对不同路段滑道的有效性。在海卡尼亚落叶林中建立了162个长10米、宽4米的样地，以评估地面采伐交通造成的土壤径流和土壤流失。实验设置包括三个级别的交通强度(3、8和16个滑道)，两个级别的坡度(≤20%和>20%)，三个级别的曲率(窄=高偏转角，60°-70°;宽=低偏角，110°-130°，直尾段)，三种覆盖类型(裸土覆盖，木屑覆盖，稻草覆盖)。每个处理组合重复3次，得到972个土壤样品。平均地表径流量和土壤流失量在弯道段和直道段之间存在显著差异，且与曲度密切相关，曲度越紧，影响程度越严重。覆盖处理对整个滑道的地表径流量和土壤流失量有显著的改善作用。木屑覆盖(SC)的平均径流量和土壤流失量(分别为0.24 g m-2和0.49 g m-2)低于秸秆覆盖(RSC)的平均径流量和土壤流失量(分别为0.45 g m-2和1.19 g m-2)，又低于未处理裸地(BS)的径流量和土壤流失量(分别为0.70 g m-2和2.31 g m-2)。地表径流量与土壤流失量呈显著正相关，与干容重、车辙深度呈正相关，与凋落物质量、总孔隙度、大孔隙度呈负相关。地表覆盖是控制滑动扰动后侵蚀损失的一种成功措施，特别是在侵蚀潜力高的陡坡小径的折回曲线上。
{"title":"Evaluating the Effectiveness of Mulching for Reducing Soil Erosion in Skid Trail Switchbacks","authors":"A. Solgi, E. Zenner, R. Naghdi, Ali Masumian, Ramin Shoja, Frashad Keivan Behjou","doi":"10.5552/crojfe.2022.1294","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1294","url":null,"abstract":"Forest operations can lead to increased runoff and soil loss on roads and skid trails. The aim of this study was to evaluate the effectiveness of two erosion control treatments applied to different segments of skid trails following six natural rainfall events. A total of 162 plots 10 m long by 4 m wide were established in a Hyrcanian deciduous forest to assess soil runoff and soil loss following ground-based harvesting traffic. The experimental setup consisted of three levels of traffic intensity (three, eight and 16 skidder passes), two levels of slope gradient (≤20% and >20%), three classes of curvature (narrow = high deflection angle, 60°–70°; wide = low deflection angle, 110°–130°, and straight trail segments), and three classes of mulch cover (bare soil, sawdust cover, and rice straw cover). Each treatment combination was replicated three times, yielding 972 soil samples. The average surface runoff volume and soil loss differed significantly between the switchbacks and the straight trail segments and depended strongly on the degree of curvature, with severity of adverse effects increasing with curve tightness. Mulch cover treatments had a significant ameliorating effect on the surface runoff volume and soil loss throughout the skid trail. The average runoff and soil loss from the skid trails treated with sawdust cover (SC) (0.24 g m-2 (mm) and 0.49 g m-2, respectively) were lower than on trails covered with rice straw (RSC) (0.45 g m-2 and 1.19 g m-2, respectively), which were, in turn lower than on untreated bare soil (BS) trail segments (0.70 g m-2 and 2.31 g m-2, respectively). Surface runoff volume was significantly positively correlated with soil loss and both were positively correlated with dry bulk density and rut depth and negatively correlated with litter mass, total porosity, and macroporosity. Surface cover is a successful measure for controlling erosion losses following skidding disturbances, particularly in the switchback curves of trails on steep slopes where erosion potential is high.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"38 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1779
M. Lotfalian, S. Peyrov, K. Adeli, Tibor Pentek
Today, transportation network optimization has become one of the significant aspects of supply chain planning, and even a slight rise in productivity can significantly reduce costs of distribution of wood in the transportation network. In the forest based industry, given that transportation is the main cost of raw wood supply, using transportation planning, distribution should be done in a way so as to minimize the overall wood displacement. Such planning must meet the needs of all demand centers and the distribution supplier points must be used to their full capacity. Accordingly, the present study strived to find an optimal solution for transportation and distribution of raw wood from the main supplier points to small and large centers of wood and paper industries in Iran. This optimization simultaneously focuses on several products and is at the macroeconomic level of the country wood market. To achieve this goal, linear programming – Transportation Simplex Algorithm was used. The results show a significant fall in transportation costs and a more organized wood distribution network than the current situation. This cost reduction can be attributed to decisions about the optimal distribution of wood types, determining transport routes, and opting for the right type of truck supplier based on load tonnage and distance. This plummet in transportation costs plunges the cost of wood and wood products, which will surge competition in the business and will be of interest to manufacturers, distributors, customers and stakeholders in general.
{"title":"Determination of Optimal Distribution and Transportation Network","authors":"M. Lotfalian, S. Peyrov, K. Adeli, Tibor Pentek","doi":"10.5552/crojfe.2022.1779","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1779","url":null,"abstract":"Today, transportation network optimization has become one of the significant aspects of supply chain planning, and even a slight rise in productivity can significantly reduce costs of distribution of wood in the transportation network. In the forest based industry, given that transportation is the main cost of raw wood supply, using transportation planning, distribution should be done in a way so as to minimize the overall wood displacement. Such planning must meet the needs of all demand centers and the distribution supplier points must be used to their full capacity. Accordingly, the present study strived to find an optimal solution for transportation and distribution of raw wood from the main supplier points to small and large centers of wood and paper industries in Iran. This optimization simultaneously focuses on several products and is at the macroeconomic level of the country wood market. To achieve this goal, linear programming – Transportation Simplex Algorithm was used. The results show a significant fall in transportation costs and a more organized wood distribution network than the current situation. This cost reduction can be attributed to decisions about the optimal distribution of wood types, determining transport routes, and opting for the right type of truck supplier based on load tonnage and distance. This plummet in transportation costs plunges the cost of wood and wood products, which will surge competition in the business and will be of interest to manufacturers, distributors, customers and stakeholders in general.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1596
Gernot Erber, Christoph Gollob, Ralf Kraßnitzer, A. Nothdurft, K. Stampfer
Cross-cutting of a tree into a set of assortments (»bucking pattern«) presents a large potential for optimizing the volume and value recovery; therefore, bucking pattern optimization has been studied extensively in the past. However, it has not seen widespread adoption in chainsaw bucking, where time consuming and costly manual measurement of input parameters is required for taper curve estimation. The present study investigated an alternative approach, where taper curves are fit based on terrestrial laser scanning data (TLS), and how deviations from observed taper curves (REF) affect the result of bucking pattern optimization. In addition, performance of TLS was compared to a traditional, segmental taper curve estimation approach (APP) and an experienced chainsaw operator’s solution (CHA).A mature Norway Spruce stand was surveyed by stationary terrestrial laser scanning. In TLS, taper curves were fit by a mixed-effects B-spline regression approach to stem diameters extracted from 3D point cloud data. A network analysis technique algorithm was used for bucking pattern optimization during harvesting. Stem diameter profiles and the chainsaw operator’s bucking pattern were obtained by manual measurement. The former was used for post-operation fit of REF taper curves by the same approach as in TLS. APP taper curves were fit based on part of the data. For 35 trees, TLS and APP taper curves were compared to REF on tree, trunk and crown section level. REF and APP bucking patterns were optimized with the same algorithm as in TLS. For 30 trees, TLS, APP and CHA bucking patterns were compared to REF on operation and tree level.Taper curves were estimated with high accuracy and precision (underestimated by 0.2 cm on average (SD=1.5 cm); RMSE=1.5 cm) in TLS and the fit outperformed APP. Volume and value recovery were marginally higher in TLS (0.6%; 0.9%) than in REF on operation level, while substantial differences were observed for APP (–6.1%; –4.1%). Except for cumulated nominal length, no significant differences were observed between TLS and REF on tree level, while APP result was inferior throughout. Volume and value recovery in CHA was significantly higher (2.1%; 2.4%), but mainly due to a small disadvantage of the optimization algorithm.The investigated approach based on terrestrial laser scanning data proved to provide highly accurate and precise estimations of the taper curves. Therefore, it can be considered a further step towards increased accuracy, precision and efficiency of bucking pattern optimization in chainsaw bucking.
将树横切成一组分类(“屈曲模式”)，为优化体积和价值恢复提供了巨大的潜力;因此，屈曲模式优化在过去得到了广泛的研究。然而，它并没有在链锯屈曲中被广泛采用，因为在链锯屈曲中，需要对输入参数进行耗时且昂贵的手动测量来估计锥度曲线。本研究探讨了一种基于地面激光扫描数据(TLS)拟合锥度曲线的替代方法，以及与观测到的锥度曲线(REF)的偏差如何影响屈曲模式优化结果。此外，将TLS的性能与传统的分段锥度曲线估计方法(APP)和经验丰富的链锯操作员解决方案(CHA)进行了比较。采用固定式地面激光扫描对挪威云杉成熟林分进行了测量。在TLS中，采用混合效应b样条回归方法对从三维点云数据中提取的茎直径进行拟合。采用网络分析技术对收获过程中的屈曲模式进行优化。通过人工测量获得了阀杆直径轮廓和电锯操作工的屈曲模式。前者用于REF锥度曲线的术后拟合，方法与TLS相同。根据部分数据拟合APP锥度曲线。对35棵树的TLS和APP锥度曲线与REF在树、树干和树冠剖面水平上进行了比较。REF和APP的屈曲模式采用与TLS相同的算法进行优化。对于30棵树，将TLS、APP和CHA屈曲模式与REF在操作和树级上进行比较。估计锥度曲线具有较高的准确度和精密度(平均低估0.2 cm (SD=1.5 cm));TLS的RMSE=1.5 cm)和拟合优于APP。TLS的体积和价值回收率略高(0.6%;在操作水平上，APP与REF相比差异显著(-6.1%;-4.1%)。除了累积标称长度外，TLS和REF在树水平上无显著差异，而APP的结果则始终较差。CHA的体积和价值回收率显著提高(2.1%;2.4%)，但主要是由于优化算法的一个小缺点。所研究的基于地面激光扫描数据的方法能够提供高精度的锥度曲线估计。因此，它可以被认为是进一步提高链锯屈曲模式优化的精度、精度和效率的一步。
{"title":"Stem-Level Bucking Pattern Optimization in Chainsaw Bucking Based on Terrestrial Laser Scanning Data","authors":"Gernot Erber, Christoph Gollob, Ralf Kraßnitzer, A. Nothdurft, K. Stampfer","doi":"10.5552/crojfe.2022.1596","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1596","url":null,"abstract":"Cross-cutting of a tree into a set of assortments (»bucking pattern«) presents a large potential for optimizing the volume and value recovery; therefore, bucking pattern optimization has been studied extensively in the past. However, it has not seen widespread adoption in chainsaw bucking, where time consuming and costly manual measurement of input parameters is required for taper curve estimation. The present study investigated an alternative approach, where taper curves are fit based on terrestrial laser scanning data (TLS), and how deviations from observed taper curves (REF) affect the result of bucking pattern optimization. In addition, performance of TLS was compared to a traditional, segmental taper curve estimation approach (APP) and an experienced chainsaw operator’s solution (CHA).A mature Norway Spruce stand was surveyed by stationary terrestrial laser scanning. In TLS, taper curves were fit by a mixed-effects B-spline regression approach to stem diameters extracted from 3D point cloud data. A network analysis technique algorithm was used for bucking pattern optimization during harvesting. Stem diameter profiles and the chainsaw operator’s bucking pattern were obtained by manual measurement. The former was used for post-operation fit of REF taper curves by the same approach as in TLS. APP taper curves were fit based on part of the data. For 35 trees, TLS and APP taper curves were compared to REF on tree, trunk and crown section level. REF and APP bucking patterns were optimized with the same algorithm as in TLS. For 30 trees, TLS, APP and CHA bucking patterns were compared to REF on operation and tree level.Taper curves were estimated with high accuracy and precision (underestimated by 0.2 cm on average (SD=1.5 cm); RMSE=1.5 cm) in TLS and the fit outperformed APP. Volume and value recovery were marginally higher in TLS (0.6%; 0.9%) than in REF on operation level, while substantial differences were observed for APP (–6.1%; –4.1%). Except for cumulated nominal length, no significant differences were observed between TLS and REF on tree level, while APP result was inferior throughout. Volume and value recovery in CHA was significantly higher (2.1%; 2.4%), but mainly due to a small disadvantage of the optimization algorithm.The investigated approach based on terrestrial laser scanning data proved to provide highly accurate and precise estimations of the taper curves. Therefore, it can be considered a further step towards increased accuracy, precision and efficiency of bucking pattern optimization in chainsaw bucking.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1303
Omar Mendoza-Trejo, Arturo D. López Rojas, D. Morales, O. Lindroos, C. Cruz-Villar, Pedro La Hera
Although most mechanized forestry work relies heavily on cranes for handling logs along the supply chain, there has been little research on how to improve cranes design. In addition, the available research has mainly focused on improving current designs, so there is a lack of application of modern methods for designing cranes with improved efficiency.This paper analyzes how a mechanical engineering design method, known as gravity compensation, can be used to make a new generation of highly energy efficient forestry cranes. To introduce this design approach, a standard forwarder crane with two booms is used as a model system on which to apply gravity compensation concepts. The design methodology follows a procedure based on physics and mathematical optimization, with the objective of minimizing the energy needed to move the crane by using gravity compensation via counterweights. To this end, we considered to minimize mechanical power, because this quantity relates to how fuel and hydraulic fluid are converted into mechanical motion.This analysis suggests that using gravity compensation could reduce energy consumption due to crane work by 27%, at the cost of increasing the crane total mass by 57%. Thus, the original crane mass of 559 kg increases to 879 kg after applying gravity compensation with counterweights. However, overall reductions in energy consumption would depend on both the crane work and the extraction distance. The greater the extraction distance, the lower the total savings. However, energy consumption savings of around 2% could be achieved even with an extraction distance of 1 km.From a design perspective, this study emphasized the need to consider gravity compensation in the design philosophy of forestry cranes, not only for its ability to minimize energy consumption, but also due to all the inherited properties it provides. This initial study concludes that designing cranes with a combination of gravity compensation concepts could yield a new generation of highly energy efficient cranes with energy savings exceeding those reported here.
{"title":"Exploring the Design of Highly Energy Efficient Forestry Cranes using Gravity Compensation","authors":"Omar Mendoza-Trejo, Arturo D. López Rojas, D. Morales, O. Lindroos, C. Cruz-Villar, Pedro La Hera","doi":"10.5552/crojfe.2022.1303","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1303","url":null,"abstract":"Although most mechanized forestry work relies heavily on cranes for handling logs along the supply chain, there has been little research on how to improve cranes design. In addition, the available research has mainly focused on improving current designs, so there is a lack of application of modern methods for designing cranes with improved efficiency.This paper analyzes how a mechanical engineering design method, known as gravity compensation, can be used to make a new generation of highly energy efficient forestry cranes. To introduce this design approach, a standard forwarder crane with two booms is used as a model system on which to apply gravity compensation concepts. The design methodology follows a procedure based on physics and mathematical optimization, with the objective of minimizing the energy needed to move the crane by using gravity compensation via counterweights. To this end, we considered to minimize mechanical power, because this quantity relates to how fuel and hydraulic fluid are converted into mechanical motion.This analysis suggests that using gravity compensation could reduce energy consumption due to crane work by 27%, at the cost of increasing the crane total mass by 57%. Thus, the original crane mass of 559 kg increases to 879 kg after applying gravity compensation with counterweights. However, overall reductions in energy consumption would depend on both the crane work and the extraction distance. The greater the extraction distance, the lower the total savings. However, energy consumption savings of around 2% could be achieved even with an extraction distance of 1 km.From a design perspective, this study emphasized the need to consider gravity compensation in the design philosophy of forestry cranes, not only for its ability to minimize energy consumption, but also due to all the inherited properties it provides. This initial study concludes that designing cranes with a combination of gravity compensation concepts could yield a new generation of highly energy efficient cranes with energy savings exceeding those reported here.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1699
Tomislav Dubravac, D. Barčić, M. Moro
The Mediterranean forest region has been exposed to anthropogenic impacts for centuries, and the constant biotic and abiotic factors, together with increasing climate change, have hindered the proper management of forest ecosystems. This study presents the results of multiyear, systematic, specific and practical monitoring of the conversion of holm oak coppices using the principles of the shelterwood system. It also presents the growth and development dynamics of the stand on a permanent experimental plot from 1997 to 2017. The research was performed in the Eumediterranean vegetation zone of coniferous forest (Forest Management, Buzet branch, Pula Forestry Office, Magran Cuf management unit, compartment 83a). The plot has all the properties of a holm oak and manna ash forests (Orno-Quercetum ilicis H-ić/1956/1958). The basic elements of stand structure were monitored: diameter at breast height (DBH), tree height, horizontal crown projection, crown ground shading (light) and the appearance and abundance of all woody vegetation, with special emphasis on the growth and development of young generations of holm oak from seed. The paper also describes the threats limiting growth, development and survival of holm oak from seed (strong shooting tendencies of coppiced holm oak and bay laurel trees, excessive presence of shrubs). Forest management requires effective, timely and repeated tending to thin stands (already under the canopy), while also protecting young trees from wild game. The statistical method of interpolation determined the trends of stand development; trend equation with coefficient of determination (R2) is very high. This indicates the growth and development of the stand in the direction of renewal of holm oak stands. Shelterwood cutting, with regular and timely tending of young generations of trees through a seven-year regeneration period, resulted in a high quality young high forest of holm oak, the first of its kind in the broader Mediterranean area. The indigenous stands of holm oak, as the fundamental climatogenic coniferous species of the Mediterranean species, have multiple roles such as protection from erosion, resilience to biotic and abiotic factors and forest fires, tourism and landscape functions, and other general forest functions, and therefore deserve intensive and ongoing research. Holm oak stands also play a part in conserving genetic and biological diversity, the potential and persistence of forest ecosystems, improving stand structure, stability and resilience of forest ecosystems to climate change, and in the long-term increase the commercial value of forest stands in the Croatian Mediterranean.
几个世纪以来，地中海森林区域一直受到人为影响，不断出现的生物和非生物因素，加上日益加剧的气候变化，阻碍了对森林生态系统的适当管理。本研究介绍了利用防护林系统的原理对黑栎乔木转化进行多年、系统、具体和实际监测的结果。它还展示了1997年至2017年永久试验田上林分的生长和发展动态。研究是在针叶林的真地中海植被带进行的(森林管理，Buzet分部，Pula林业办公室，Magran Cuf管理单位，83a室)。该地块具有霍尔姆橡树和甘露灰森林(Orno-Quercetum ilicis h - iki /1956/1958)的所有特性。监测了林分结构的基本要素:胸径(DBH)、树高、水平树冠投影、树冠地面遮阳(光)以及所有木本植被的外观和丰度，特别强调了黑栎幼苗的生长发育情况。本文还介绍了从种子方面限制黑栎生长、发育和生存的威胁(覆膜黑栎和月桂树的强烈倒枝倾向，灌木的过度存在)。森林管理需要有效、及时和反复地照料稀疏的林分(已经在树冠下)，同时也要保护幼树免受野生动物的侵害。统计插值法确定林分发展趋势;趋势方程的决定系数(R2)非常高。这表明林分的生长发育方向是阴栎林分更新的方向。通过七年的再生期，定期和及时地对年轻一代的树木进行砍伐，形成了高质量的霍尔姆橡树幼林，这在更广泛的地中海地区是第一个。黑栎作为地中海树种中最基本的气候针叶林种，具有多种保护作用，如防止侵蚀、抵御生物和非生物因素、森林火灾、旅游和景观功能以及其他一般森林功能，因此值得深入和持续的研究。黑栎林还在保护遗传和生物多样性、森林生态系统的潜力和持久性、改善林分结构、森林生态系统对气候变化的稳定性和复原力以及长期增加克罗地亚地中海林分的商业价值方面发挥作用。
{"title":"Growth and Development Dynamics of Young Holm Oak (Quercus Ilex L.) Stands after Shelterwood Cutting in Open Forest Road Conditions","authors":"Tomislav Dubravac, D. Barčić, M. Moro","doi":"10.5552/crojfe.2022.1699","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1699","url":null,"abstract":"The Mediterranean forest region has been exposed to anthropogenic impacts for centuries, and the constant biotic and abiotic factors, together with increasing climate change, have hindered the proper management of forest ecosystems. This study presents the results of multiyear, systematic, specific and practical monitoring of the conversion of holm oak coppices using the principles of the shelterwood system. It also presents the growth and development dynamics of the stand on a permanent experimental plot from 1997 to 2017. The research was performed in the Eumediterranean vegetation zone of coniferous forest (Forest Management, Buzet branch, Pula Forestry Office, Magran Cuf management unit, compartment 83a). The plot has all the properties of a holm oak and manna ash forests (Orno-Quercetum ilicis H-ić/1956/1958). The basic elements of stand structure were monitored: diameter at breast height (DBH), tree height, horizontal crown projection, crown ground shading (light) and the appearance and abundance of all woody vegetation, with special emphasis on the growth and development of young generations of holm oak from seed. The paper also describes the threats limiting growth, development and survival of holm oak from seed (strong shooting tendencies of coppiced holm oak and bay laurel trees, excessive presence of shrubs). Forest management requires effective, timely and repeated tending to thin stands (already under the canopy), while also protecting young trees from wild game. The statistical method of interpolation determined the trends of stand development; trend equation with coefficient of determination (R2) is very high. This indicates the growth and development of the stand in the direction of renewal of holm oak stands. Shelterwood cutting, with regular and timely tending of young generations of trees through a seven-year regeneration period, resulted in a high quality young high forest of holm oak, the first of its kind in the broader Mediterranean area. The indigenous stands of holm oak, as the fundamental climatogenic coniferous species of the Mediterranean species, have multiple roles such as protection from erosion, resilience to biotic and abiotic factors and forest fires, tourism and landscape functions, and other general forest functions, and therefore deserve intensive and ongoing research. Holm oak stands also play a part in conserving genetic and biological diversity, the potential and persistence of forest ecosystems, improving stand structure, stability and resilience of forest ecosystems to climate change, and in the long-term increase the commercial value of forest stands in the Croatian Mediterranean.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1188
Jan Mihelič, R. Robek, M. Kobal
In Slovenia, torrent areas and forest roads are being regulated and built mostly in steep, erosion-prone areas. In addition to the geometry of extrapolated works, calculating bulk factors is key for estimating haulage masses. We have determined bulk factors for compact carbonate rock, mixed soil, and carbonate deposits. Each construction site was recorded with an unmanned aerial vehicle (UAV) before the excavation and after every 4±2 m3 of excavated material. The average point cloud density was 9535 points/m2. We processed the point clouds from each construction site and determined the difference in volume between the volume of excavated area and the volume of deposited material. The average bulk factor for compact carbonate rock is 1.42, 1.20 for mixed soil and 1.15 for carbonate deposits (calculated for fully loaded eight-wheeled truck). The calculated bulk factors for soils and carbonate deposits match with the already established values, while the factor for compact rock is 20% lower than the factor currently in use by the Slovenian forest engineers.
{"title":"Determining Bulk Factors for Three Subsoils Used in Forest Engineering in Slovenia","authors":"Jan Mihelič, R. Robek, M. Kobal","doi":"10.5552/crojfe.2022.1188","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1188","url":null,"abstract":"In Slovenia, torrent areas and forest roads are being regulated and built mostly in steep, erosion-prone areas. In addition to the geometry of extrapolated works, calculating bulk factors is key for estimating haulage masses. We have determined bulk factors for compact carbonate rock, mixed soil, and carbonate deposits. Each construction site was recorded with an unmanned aerial vehicle (UAV) before the excavation and after every 4±2 m3 of excavated material. The average point cloud density was 9535 points/m2. We processed the point clouds from each construction site and determined the difference in volume between the volume of excavated area and the volume of deposited material. The average bulk factor for compact carbonate rock is 1.42, 1.20 for mixed soil and 1.15 for carbonate deposits (calculated for fully loaded eight-wheeled truck). The calculated bulk factors for soils and carbonate deposits match with the already established values, while the factor for compact rock is 20% lower than the factor currently in use by the Slovenian forest engineers.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1563
M. Jourgholami, M. E. Abari, R. Venanzi, F. Tavankar, R. Picchio
It is well-known that soil and water conservation actions (e.g., installing water diversion structures) are necessary to restore skid trails after logging operations. However, there are some points that have yet to be determined concerning the efficacy of rehabilitation on sediment yield and nutrient export to the aquatic environment. The objectives of this study were to determine the optimal distance among the water diversion structures (WDSs) to suppress runoff, sediment yield, and measure nitrogen and phosphorus concentrations on the skid trails of a mountainous ecosystem. The study was conducted on a total of 18 bounded runoff plots, each with a width of 4 m and a length of 120 m, divided into six treatment compartments done in triplicate. Beech logs were placed at a distance of 5, 10, 20, 30, and 40 meters. An untreated area (U) was set up during the recording period from 18 September 2015 to 17 September 2016. In all the WDS treatments and untreated trails (U), the observed peaks of runoff, sediment yield, as well as nitrate and phosphate concentrations was found to be significantly correlated with the amount of rainfall events. Results show that there was a decrease in surface runoff and runoff coefficient, sediment yield, and nitrate and phosphate concentrations by installing of WDS at different distances. The runoff and runoff coefficients (2.67 mm and 0.101, respectively) were at the lowest level in the WDS20 (WDS at a distance of 20 m). The sediment yield was significantly higher on the U, 13.52 g m-2 followed by WDS40, whereas the lowest values were detected at the WDS10. Significantly higher values of nitrate were found in the U (3.63 mg l-1), while the lowest amounts of nitrate were determined at WDS5 followed by the WDS20 treatment. The highest values of phosphate were found on the U treatment (0.278 mg l-1) followed by the WDS40 treatment, whereas the lowest phosphate values were measured in the WDS20 treated area. Therefore, it can be deduced that the recommended water diversion structure should be placed at a distance of 20 m to mitigate runoff, sediment yield, nitrate and phosphate exports on the skid trails.
{"title":"Effectiveness of Water Diversion Structure to Mitigate Runoff, Sediment Yield, Nitrate and Phosphate Concentrations in Skid Trail of Mountainous Forest Ecosystem","authors":"M. Jourgholami, M. E. Abari, R. Venanzi, F. Tavankar, R. Picchio","doi":"10.5552/crojfe.2022.1563","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1563","url":null,"abstract":"It is well-known that soil and water conservation actions (e.g., installing water diversion structures) are necessary to restore skid trails after logging operations. However, there are some points that have yet to be determined concerning the efficacy of rehabilitation on sediment yield and nutrient export to the aquatic environment. The objectives of this study were to determine the optimal distance among the water diversion structures (WDSs) to suppress runoff, sediment yield, and measure nitrogen and phosphorus concentrations on the skid trails of a mountainous ecosystem. The study was conducted on a total of 18 bounded runoff plots, each with a width of 4 m and a length of 120 m, divided into six treatment compartments done in triplicate. Beech logs were placed at a distance of 5, 10, 20, 30, and 40 meters. An untreated area (U) was set up during the recording period from 18 September 2015 to 17 September 2016. In all the WDS treatments and untreated trails (U), the observed peaks of runoff, sediment yield, as well as nitrate and phosphate concentrations was found to be significantly correlated with the amount of rainfall events. Results show that there was a decrease in surface runoff and runoff coefficient, sediment yield, and nitrate and phosphate concentrations by installing of WDS at different distances. The runoff and runoff coefficients (2.67 mm and 0.101, respectively) were at the lowest level in the WDS20 (WDS at a distance of 20 m). The sediment yield was significantly higher on the U, 13.52 g m-2 followed by WDS40, whereas the lowest values were detected at the WDS10. Significantly higher values of nitrate were found in the U (3.63 mg l-1), while the lowest amounts of nitrate were determined at WDS5 followed by the WDS20 treatment. The highest values of phosphate were found on the U treatment (0.278 mg l-1) followed by the WDS40 treatment, whereas the lowest phosphate values were measured in the WDS20 treated area. Therefore, it can be deduced that the recommended water diversion structure should be placed at a distance of 20 m to mitigate runoff, sediment yield, nitrate and phosphate exports on the skid trails.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1539
W. Robb, T. Zemánek, N. Kaakkurivaara
Work safety in the forestry industry, where chainsaws are used for tree felling, continues to be a top priority. The mobility of workers involved in chainsaw operations between Europe and Asia has become more common in today’s global workplace. Therefore, sharing knowledge about the types of work safety issues found in both regions can be beneficial. Increased knowledge and safety awareness in the workplace can contribute to a reduction in chainsaw accidents. This paper identifies and addresses four key related areas, namely: regulatory frameworks; chainsaw accidents; personal protective equipment and chainsaw training. Information for both regions was evaluated via interviews, questionnaires, direct observation, desk studies, field studies and descriptive statistical analysis. A total of 234 participants responded to the main research questionnaire, which resulted in data analysis of significant questions related to the use of personal protective equipment (PPE) and possible causes of accidents. Key findings included a need for more information relating to the effect of regulations in individual countries and chainsaw accident and fatality statistics within Asia. A requirement for further research into the suitability of PPE used in Asia was identified. Inadequate training was seen as a primary factor causing accidents in Asia, while in Europe, it was due to chainsaw operators taking shortcuts. Inadequate workplace supervision and a lack of uniform and affordable training provision were common issues identified within both regions. Field tests carried out in accordance with the International/European chainsaw (ICC/ECC) qualification standards of the »non-profit« Awarding Body Association (ABA) International were successful in demonstrating the benefits of uniform training to participants in Europe and Asia. Overall, the study raises awareness of the fatal consequences of risk-taking behaviour to work safety, requiring a better understanding of the problem from a social psychology perspective. It identifies the self-employed or temporary worker groups as high-risk categories in both regions, with younger workers seen to be more at risk of injury in Asia and older workers more at risk in Europe. The findings demonstrate that, while there are differences between the two regions (at least within the participating countries), it is essential to provide quality education and raise skills by training and promotion of supervision in order to prevent chainsaw accidents. This can lead to the development of the building blocks of a holistic approach to safety in forestry work, which, as shown in this paper, can result in a decrease in the occurrence of accidents.
{"title":"An Analysis of Chainsaw Operator Safety Between Asian and European Countries","authors":"W. Robb, T. Zemánek, N. Kaakkurivaara","doi":"10.5552/crojfe.2022.1539","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1539","url":null,"abstract":"Work safety in the forestry industry, where chainsaws are used for tree felling, continues to be a top priority. The mobility of workers involved in chainsaw operations between Europe and Asia has become more common in today’s global workplace. Therefore, sharing knowledge about the types of work safety issues found in both regions can be beneficial. Increased knowledge and safety awareness in the workplace can contribute to a reduction in chainsaw accidents. This paper identifies and addresses four key related areas, namely: regulatory frameworks; chainsaw accidents; personal protective equipment and chainsaw training. Information for both regions was evaluated via interviews, questionnaires, direct observation, desk studies, field studies and descriptive statistical analysis. A total of 234 participants responded to the main research questionnaire, which resulted in data analysis of significant questions related to the use of personal protective equipment (PPE) and possible causes of accidents. Key findings included a need for more information relating to the effect of regulations in individual countries and chainsaw accident and fatality statistics within Asia. A requirement for further research into the suitability of PPE used in Asia was identified. Inadequate training was seen as a primary factor causing accidents in Asia, while in Europe, it was due to chainsaw operators taking shortcuts. Inadequate workplace supervision and a lack of uniform and affordable training provision were common issues identified within both regions. Field tests carried out in accordance with the International/European chainsaw (ICC/ECC) qualification standards of the »non-profit« Awarding Body Association (ABA) International were successful in demonstrating the benefits of uniform training to participants in Europe and Asia. Overall, the study raises awareness of the fatal consequences of risk-taking behaviour to work safety, requiring a better understanding of the problem from a social psychology perspective. It identifies the self-employed or temporary worker groups as high-risk categories in both regions, with younger workers seen to be more at risk of injury in Asia and older workers more at risk in Europe. The findings demonstrate that, while there are differences between the two regions (at least within the participating countries), it is essential to provide quality education and raise skills by training and promotion of supervision in order to prevent chainsaw accidents. This can lead to the development of the building blocks of a holistic approach to safety in forestry work, which, as shown in this paper, can result in a decrease in the occurrence of accidents.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1683
Yue Zhu, Jiangming Kan, Fenglu Liu
Forest roads are short of structured terrain. Individual wheels often cannot contact the ground when conventional chassis is driving, and the mobility is weak. In addition, the lateral rollover usually occurs. In this article, a forestry chassis with a novel articulated structure with three degrees of freedom (FC-3DOF(II)) is proposed. Compared with conventional chassis, the novel articulated structure is designed, which contributes to achieving full-time contact between wheels and ground. The mobility is improved. For the lateral stability, the previous lateral rollover model of chassis is often established by the geometrical position of COG (center of gravity) of the frame. This method is applied with limitations, which is not universal. Therefore, a new accurate lateral rollover model for FC-3DOF(II) is derived, which predicts the lateral stability by analyzing tire contact forces. The new lateral rollover model is more general and recovers the previous model. To verify the theoretical analysis exactly, the virtual prototype of FC-3DOF(II) is established in SolidWorks, and simulations of lateral rollover are carried out in ADAMS. In simulation experiments, the lateral stability is predicted by analyzing tire contact forces when the inclination of terrain is increasing. Two conditions are considered in simulations. The lateral stability of FC-3DOF(II) and FC-3DOF(II) installed rectangular objects. Compared to the simulation and theoretical results, for FC-3DOF(II), the maximum absolute percent difference of the contact force with the theoretical analysis relative to the simulation is only 1.83%. For FC-3DOF(II) installed rectangular objects, the simulation results show that the lateral rollover is caused by the rear up-slope wheel when the inclination of terrain reaches 34°. The theoretical result relative to the simulation is only 2.90%. The maximum absolute percent difference of the contact force with the theoretical analysis relative to the simulation is only 2.50%. Simulation results validate the effectiveness of the proposed lateral rollover model in two conditions.
{"title":"A Research of Design, Lateral Stability and Simulation for a Chassis Running in Forest","authors":"Yue Zhu, Jiangming Kan, Fenglu Liu","doi":"10.5552/crojfe.2022.1683","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1683","url":null,"abstract":"Forest roads are short of structured terrain. Individual wheels often cannot contact the ground when conventional chassis is driving, and the mobility is weak. In addition, the lateral rollover usually occurs. In this article, a forestry chassis with a novel articulated structure with three degrees of freedom (FC-3DOF(II)) is proposed. Compared with conventional chassis, the novel articulated structure is designed, which contributes to achieving full-time contact between wheels and ground. The mobility is improved. For the lateral stability, the previous lateral rollover model of chassis is often established by the geometrical position of COG (center of gravity) of the frame. This method is applied with limitations, which is not universal. Therefore, a new accurate lateral rollover model for FC-3DOF(II) is derived, which predicts the lateral stability by analyzing tire contact forces. The new lateral rollover model is more general and recovers the previous model. To verify the theoretical analysis exactly, the virtual prototype of FC-3DOF(II) is established in SolidWorks, and simulations of lateral rollover are carried out in ADAMS. In simulation experiments, the lateral stability is predicted by analyzing tire contact forces when the inclination of terrain is increasing. Two conditions are considered in simulations. The lateral stability of FC-3DOF(II) and FC-3DOF(II) installed rectangular objects. Compared to the simulation and theoretical results, for FC-3DOF(II), the maximum absolute percent difference of the contact force with the theoretical analysis relative to the simulation is only 1.83%. For FC-3DOF(II) installed rectangular objects, the simulation results show that the lateral rollover is caused by the rear up-slope wheel when the inclination of terrain reaches 34°. The theoretical result relative to the simulation is only 2.90%. The maximum absolute percent difference of the contact force with the theoretical analysis relative to the simulation is only 2.50%. Simulation results validate the effectiveness of the proposed lateral rollover model in two conditions.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"1 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.5552/crojfe.2022.1054
M. Kormanek
Wood harvesting with the use of wheeled harvesters is now common in Polish and Czech forests. While moving in the forest, the wheels of these machines affect the forest soil and the extent of this impact is interesting. The paper presents the results of measurements of the changes that occur in the soil on the operational trails after the timber harvesting using the Entracon Sioux EH30 thinning harvester. The measurements were taken on fragments of three operational trails, in and between the ruts and at a distance of 1.0 m off the trail. An impact penetrometer was used to measure the penetration resistance, soil samples were collected to determine the bulk density and moisture content, and soil deformations on the trail were measured with a profile meter. Unit pressures exerted by harvester wheels on the ground were determined. It was shown that in the places where the harvester wheels pass, even of a small weight (5.73 tons, 8 wheels) and with unit pressures of the wheels on the ground <50 kPa, changes in soil parameters occurred. A statistically significant increase in penetration resistance in relation to the control occurred at a depth of up to 35 cm, while at a depth of up to 5 cm the increase was more than 2-fold. There was also a slight decrease in soil moisture content (up to 7.9%) and an increase (up to 8.4%) in bulk density in the ruts, while rut depths were small and reached 4 cm. As it was shown, the impact penetrometer, simple in design, which was assumed to be used for measurements, and which is not used in this type of research in forestry, despite its limitations, can be used to determine the compactness of the soil and its changes resulting from machine work.
{"title":"Use of Impact Penetrometer to Determine Changes in Soil Compactness After Entracon Sioux EH30 Timber Harvesting","authors":"M. Kormanek","doi":"10.5552/crojfe.2022.1054","DOIUrl":"https://doi.org/10.5552/crojfe.2022.1054","url":null,"abstract":"Wood harvesting with the use of wheeled harvesters is now common in Polish and Czech forests. While moving in the forest, the wheels of these machines affect the forest soil and the extent of this impact is interesting. The paper presents the results of measurements of the changes that occur in the soil on the operational trails after the timber harvesting using the Entracon Sioux EH30 thinning harvester. The measurements were taken on fragments of three operational trails, in and between the ruts and at a distance of 1.0 m off the trail. An impact penetrometer was used to measure the penetration resistance, soil samples were collected to determine the bulk density and moisture content, and soil deformations on the trail were measured with a profile meter. Unit pressures exerted by harvester wheels on the ground were determined. It was shown that in the places where the harvester wheels pass, even of a small weight (5.73 tons, 8 wheels) and with unit pressures of the wheels on the ground <50 kPa, changes in soil parameters occurred. A statistically significant increase in penetration resistance in relation to the control occurred at a depth of up to 35 cm, while at a depth of up to 5 cm the increase was more than 2-fold. There was also a slight decrease in soil moisture content (up to 7.9%) and an increase (up to 8.4%) in bulk density in the ruts, while rut depths were small and reached 4 cm. As it was shown, the impact penetrometer, simple in design, which was assumed to be used for measurements, and which is not used in this type of research in forestry, despite its limitations, can be used to determine the compactness of the soil and its changes resulting from machine work.","PeriodicalId":55204,"journal":{"name":"Croatian Journal of Forest Engineering","volume":"17 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71027469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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