European Journal of Forest Engineering最新文献_第8页

Effect of Tire Size on Skidder Productivity Under Wet Conditions 湿工况下轮胎尺寸对打滑器生产率的影响

European Journal of Forest Engineering Pub Date : 2001-01-01 DOI: 10.1080/08435243.2001.10702764

J. Klepac, B. Stokes, J. Roberson

引用次数: 5

Where are all the Forest Engineers? 森林工程师都去哪了?

European Journal of Forest Engineering Pub Date : 2001-01-01 DOI: 10.1080/08435243.2001.10702762

引用次数: 0

Quantitative Analysis of Fragmented Landscape Patterns Resulting from Timber Harvesting Practices in Kyoto University Forests 京都大学森林采伐造成的破碎化景观格局定量分析

European Journal of Forest Engineering Pub Date : 2001-01-01 DOI: 10.1080/08435243.2001.10702759

M. Shiba

{"title":"Quantitative Analysis of Fragmented Landscape Patterns Resulting from Timber Harvesting Practices in Kyoto University Forests","authors":"M. Shiba","doi":"10.1080/08435243.2001.10702759","DOIUrl":"https://doi.org/10.1080/08435243.2001.10702759","url":null,"abstract":"Abstract This paper presents the use of a set of spatial statistics to quantify the forest landscape pattern caused by the patchwork of timber harvesting and the subsequent coniferous plantations made over a 60-year period (1921–1981) in the natural forests of Kyoto University Forests. Aerial photography and orthophotography were used to analyze spatial patterns of forest cover changes at patch level between 1974 and 1996. Base maps of forest pattern were digitized in raster format using four dominant forest cover types in the study area The total number of digitized patches for 1974 and 1996 were 435 and 453, respectively. Four groups of indices were employed to quantify landscape heterogeneity and pattern for each of the two years: (1) patch size; (2) patch abundance; (3) patch shape; and (4) patch spacing. Patch abundance and patch spacing measures provided considerable information on major patterns of forest landscape dynamics over time. Patch size and shape indices contributed information on specific characteristics of the individual patches and may be useful for applications designed to study specific interior and edge habitats or for the prescription of forest cutting patterns and/or cutting-unit size. The net loss of forest covers that occurred during 60-year period trends to be balanced primarily by regeneration of areas cut before 1943 and secondarily by plantation of areas cut before 1965.","PeriodicalId":36173,"journal":{"name":"European Journal of Forest Engineering","volume":"104 1","pages":"19 - 27"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75921234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Delivery 交付

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.2307/j.ctvcb5ck1.52

H. W. McFarlane

引用次数: 0

Fiber Recovery with Chain Flail Delimbing/Debarking and Chipping of Hybrid Poplar 杂交杨树链连枷划/脱皮和剥落法恢复纤维

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.1080/08435243.2000.10702755

B. Hartsough, R. Spinelli, Steve J. Pottle, J. Klepac

{"title":"Fiber Recovery with Chain Flail Delimbing/Debarking and Chipping of Hybrid Poplar","authors":"B. Hartsough, R. Spinelli, Steve J. Pottle, J. Klepac","doi":"10.1080/08435243.2000.10702755","DOIUrl":"https://doi.org/10.1080/08435243.2000.10702755","url":null,"abstract":"Abstract This study determined how much wood was potentially available from short rotation hybrid poplar, and how much was actually recovered when trees were delimbed and debarked with chain flails and chipped. 31 groups of five trees each were measured and then processed. For trees larger than 50 kg total dry weight, potentially recoverable wood averaged 75% of total weight. Over 95% of this wood was converted into chips. Losses due to breakage by the flails, which show up in the bark discharge, amounted to 0.8 dry kg per tree and were relatively independent of tree size. Chipper reject wood losses averaged 2.3 dry kg per tree, but increased in almost direct proportion to tree size, from 1.2 kg for 50 kg trees, to 3.2 kg for 120 kg trees. For trees less than 50 kg total dry weight, potentially recoverable wood fraction was highly variable – from 50 to 75% of total weight. Because of breakage of small stems by the flail, wood recovery was also relatively low, ranging from 40 to 95%. Most of the wood loss for smaller trees showed up in the bark discharge rather than as chipper rejects. For larger trees, the chipper rejects represent the biggest opportunity for improving the recovery of wood fiber. Sharp chipper knives appear to be important for minimizing losses. Beyond that, it is not clear whether wood in the chipper rejects is the result of bole damage by the flail or chipper design characteristics.","PeriodicalId":36173,"journal":{"name":"European Journal of Forest Engineering","volume":"107 1","pages":"59 - 68"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78927057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 24

The Evaluation of a National Forest Harvest Scheduling System for Ireland – Two Case Studies 爱尔兰国家森林采伐调度系统的评估-两个案例研究

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.1080/08435243.2000.10702751

M. Nieuwenhuis, C. Nugent

{"title":"The Evaluation of a National Forest Harvest Scheduling System for Ireland – Two Case Studies","authors":"M. Nieuwenhuis, C. Nugent","doi":"10.1080/08435243.2000.10702751","DOIUrl":"https://doi.org/10.1080/08435243.2000.10702751","url":null,"abstract":"Abstract Coillte Teoranta (the Irish Forestry Board) harvested approximately 2.0 million m3 in 1994. By the year 2000 this annual harvest is projected to increase to approximately 2.8 million m3 and to 3.7 million m3 by the year 2011. To facilitate the management of these increased timber flows more efficiently and effectively, the Harvest Scheduling System (HSS) was developed. In order to evaluate the HSS’s solutions, five case studies were carried out, two of which are presented in this paper. Initially, the HSS model was solved without any management constraints, resulting in a theoretical maximum net present value (NPV) (case study 1). Subsequently, the effect of imposing national and regional level volume fluctuation constraints was examined (case study 2). The investigations in the “no constraints” study resulted in a theoretical optimal harvest schedule for Coillte over the period 1998 to 2002. The solution showed great volume fluctuations from year to year, in terms of total volume, species, harvest type and product. It would be impossible to implement such a schedule, due to management, harvesting resources and industry requirements. However, the NPV achieved was used as a base to estimate the cost of applying management constraints in the second case study. This second study also showed that Coillte’s production smoothing process results in harvest schedules that are not feasible, as no adjustments for volume are included.","PeriodicalId":36173,"journal":{"name":"European Journal of Forest Engineering","volume":"13 1","pages":"23 - 27"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75013145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Silvicultural Result of One-Grip Harvester Operation 单握式收割机作业造林效果

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.1080/08435243.2000.10702749

M. Sirén

{"title":"Silvicultural Result of One-Grip Harvester Operation","authors":"M. Sirén","doi":"10.1080/08435243.2000.10702749","DOIUrl":"https://doi.org/10.1080/08435243.2000.10702749","url":null,"abstract":"Abstract A new method for measuring the silvicultural result of thinning is presented in the study. The measuring method was based on rectangular sample plots measured parallel to strip roads. An individual sample plot consisted of eight zones, each 30 m2 in area. Due to its considerable importance in Finland, the one-grip harvester operation was the harvesting system examined. The research material was collected from 15 stands amounting to a total area of 14.7 ha. The post-harvesting inventory provided good information on the removed and standing trees, their size and distribution. The number and distribution of standing and removed trees were according to Finnish thinning instructions, and thinning was typical low thinning, in which smaller trees and trees of low quality are removed. The average tree damage percentage, 4.6, is acceptable. However, the proportion of damage varied from 1.1% to 9.1% with different operators. The damage was highest during the summer. Small, superficial damage was typical. The average strip road width was 4.8 m, the distance between strip roads 19.8 m and the rut depth 0.6 cm. The economic consequences of the damage was estimated using a calculation model. The model estimates the losses caused by strip roads, tree and soil damage. The economic consequences of harvesting damage during the rotation period was 1158 FIM (1 U$ = 5.60 FIM). Strip roads make a significant contribution to the amount of costs. Due to the high variation in the harvesting quality, both the continuing supervision of the silvicultural thinning result and the training of machine operators are necessary. Thinning spruce stands during the sap period should be avoided due to the high risk of tree damage, and decay following damage. Generally, it is possible to obtain a good silvicultural thinning result with one-grip harvester operation.","PeriodicalId":36173,"journal":{"name":"European Journal of Forest Engineering","volume":"41 1","pages":"14 - 7"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84560558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Endurance of Compacted Steel Wire Ropes 压缩钢丝绳的耐久性

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.1080/08435243.2000.10702753

H. Torgersen

引用次数: 3

Road Alignment and Gradient Issues in the Maintenance of Logging Roads in Tanzania 坦桑尼亚伐木道路养护中的道路线形和坡度问题

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.3846/08435243.2000.10702750

W. Abeli, D. T. Shemwetta, R. O. Meiludie, M. Kachwele

{"title":"Road Alignment and Gradient Issues in the Maintenance of Logging Roads in Tanzania","authors":"W. Abeli, D. T. Shemwetta, R. O. Meiludie, M. Kachwele","doi":"10.3846/08435243.2000.10702750","DOIUrl":"https://doi.org/10.3846/08435243.2000.10702750","url":null,"abstract":"Abstract In forestry, roads are essential structures as they provide access to the forest from the establishment phase to harvesting stage. Thus it is important that roads are properly planned, constructed and maintained in order to ensure easy access, smooth transport of forest products, safety, comfort and economy on vehicle operations. For Tanzania where commercial timber harvesting in plantation forests has just started, appropriate values of parameters for road alignment and gradient, in the context of the country’s settings, need to be established. This study, which was carried out on a gravel secondary access road, established that traffic and water contribute significantly to road deterioration or loss of road surface materials. Road alignment and road gradient were found to influence the rate of soil loss. The study found that the optimal road grade and curve radii which minimized road maintenance cost in this area were grades less than 6% and radii above 100m respectively. Statistical analysis however showed that there was no significant difference between straight sections of the road and the curve sections in terms of loss of surface layer materials.","PeriodicalId":36173,"journal":{"name":"European Journal of Forest Engineering","volume":"10 1","pages":"15 - 21"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75464358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Damage to Natural Regeneration in the Hyrcanian Forests of Iran: A Comparison of Two Typical Timber Extraction Operations 对伊朗海卡尼亚森林自然再生的损害:两种典型木材采伐作业的比较

European Journal of Forest Engineering Pub Date : 2000-06-01 DOI: 10.1080/08435243.2000.10702756

S. Hosseini, Baris Madjnonian, M. Nieuwenhuis

引用次数: 20