scholarly journals MECHANISED HARVEST OF ENERGY WOOD: STATE-OF-THE-ART AND NEW DEVELOPMENTS

2016 ◽  
Vol 24 (1) ◽  
pp. 32-40
Author(s):  
Ralf Pecenka ◽  
Jadir Nogueira Silva ◽  
Detlef Ehlert ◽  
Gerd Volkhard Scholz
Keyword(s):  
Field Performance ◽  
Stem Diameter ◽  
Fast Growing ◽  
Mountainous Regions ◽  
Energy Wood ◽  
Short Rotation ◽  
Low Weight ◽  
Production Technologies ◽  
And Performance ◽  
Forage Harvester

Energy wood from fast growing trees, also called short rotation coppice (SRC) such as poplar, willow and eucalyptus, may provide a secure source of income for farmers, provided that production technologies, logistic chains and end user facilities are well designed in farmers’ regional structures. One of the key problems at present is the lack of inexpensive harvesting machinery. Analyzing the process chain of fast growing trees, chip lines seem to be most costefficient for harvest, and the modification of forage harvesters is a promising option. But the high machine weight of forage harvesters is a serious disadvantage for harvest in rain-laden or mountainous regions. Furthermore, for economic operation of these expensive harvest systems cultivation areas of more than 300 ha are required. Therefore, a simple and low weight tractor-mounted mower-chipper for medium sized standard tractors has been developed. The chipper is designed for flexible harvest of wood from fast growing trees (max. stem diameter 15 cm). The total weight of the harvester (tractor and chipper) is less than 50 % of the forage harvester combination resulting in much more flexible field operation and lower harvest costs. The machine has been successfully tested in the last three harvest seasons on an area of more than 110 ha. At harvest of 4 years old poplars (10 - 15 cm stem diameter) an average field performance of 0.5 ha h-1 has been realized. Due to the robust design and performance of the prototype the development of a reinforced model is considered at present. Such a new model could be designed for harvest of poplar or eucalyptus trees with stem diameters of more than 20 cm.

scholarly journals Overstory Density Affects Field Performance of Underplanted Red Oak (Quercus rubra L.) in Ontario

1997 ◽  
Vol 14 (3) ◽  
pp. 120-125 ◽  
Author(s):  
Daniel C. Dey ◽  
William C. Parker
Keyword(s):  
Seedling Survival ◽  
Field Performance ◽  
Dry Mass ◽  
Stem Diameter ◽  
Red Oak ◽  
Light Levels ◽  
Competitive Disadvantage ◽  
Closed Canopy ◽  
Survival And Growth ◽  
And Performance

Abstract Red oak seedlings were underplanted in a closed-canopy mature northern hardwood stand and an adjacent shelterwood in central Ontario. Overstory density effects on seedling survival and growth were assessed 2 yr after planting. After 2 yr, seedling survival was 90% in the uncut stand and over 99% in the shelterwood. Seedlings in the uncut stand experienced negligible or negative annual increments in stem diameter and height. Seedlings in the shelterwood were about 2 mm larger in diameter and nearly twice as tall as those in the uncut stand after 2 yr. Second-year stem diameter and height distributions of planted oak were significantly different in the shelterwood and the uncut stand. Root volume, area, and dry mass were substantially larger for seedlings grown in the shelterwood than those in the uncut stand. Loss of vigor, growth declines, and increased mortality of planted oak were largely a result of extremely low understory light levels in the uncut stand. Results of this study suggest that red oak underplanted in an uncut stand 2 or more years before a shelterwood harvest will be at a competitive disadvantage once they are released. Establishment and performance of underplanted red oak is promoted by shelterwoods that provide adequate light at the forest floor and should exhibit a strong positive growth response following final overstory removal. North. J. Appl. For. 14(3):120-125

Energieholzproduktion in Mittel- und Nieder-wäldern der Schweiz | Energy Wood Production in Coppice With Standards and Coppice Forests in Switzerland

1999 ◽  
Vol 150 (4) ◽  
pp. 142-147
Author(s):  
Bettina Bally
Keyword(s):  
Twentieth Century ◽  
Economic Value ◽  
Wood Production ◽  
Fuel Production ◽  
Energy Wood ◽  
Short Rotation ◽  
Energy Plantations ◽  
Coppice With Standards

Coppice with standards and coppice forests are the result of silvicultural systems widely applied until the mid-twentieth century, mainly for fuel production. Similar to energy plantations in Scandinavia and Germany the above-mentioned systems are characterised by a short rotation. The present paper tries to show that, owing to efficient logging methods, energy wood can be produced from coppice and coppice with standards forests so cheaply that it proves to be highly competitive compared to oil. The economic value of coppice and coppice with standards was calculated on the basis of models and compared to high forest cultivation. Contrary to high forests, the coppice with standards system is cost-covering on poor, well developed and easily accessible sites.

Performance of two combine harvester header in soybean crops

2020 ◽  
Vol 13 (2) ◽  
pp. 1
Author(s):  
E. M. Samogim ◽  
T. C. Oliveira ◽  
Z. N. Figueiredo ◽  
J. M. B. Vanini
Keyword(s):  
Experimental Design ◽  
Crop Yield ◽  
Field Performance ◽  
Travel Speed ◽  
The Other ◽  
Combine Data ◽  
Mato Grosso ◽  
Tukey Test ◽  
Combine Harvester ◽  
And Performance

The combine harvest for soybean crops market are currently available two types of combine with header or platform, one of conventional with revolving reel with metal or plastic teeth to cause the cut crop to fall into the auger header and the other called "draper" headers that use a fabric or rubber apron instead of a cross auger, there are few test about performance of this combine header for soybean in Mato Grosso State. The aim of this work was to evaluate the soybean harvesting quantitative losses and performance using two types combine header in four travel speed. The experiment was conducted during soybean crops season 2014/15, the farm Tamboril in the municipality of Pontes e Lacerda, State of Mato Grosso. The was used the experimental design of randomized blocks, evaluating four forward harvesting speeds (4 km h-1, 5 km h-1, 6 km h-1 and 7 km h-1), the natural crops losses were analyzed, loss caused by the combine harvester (combine header, internal mechanisms and total losses) and was also estimated the  field performance of each combine. Data were submitted to analysis of variance by F test and compared of the average by Tukey test at 5% probability. The results show the draper header presents a smaller amount of total loss and in most crop yield when compared with the conventional cross auger.

Field Determined Live Load Distribution Factors for Modular Press-Brake-Formed Tub Girders

2021 ◽  
pp. 036119812098375
Author(s):  
Karl E. Barth ◽  
Gregory K. Michaelson ◽  
Adam D. Roh ◽  
Robert M. Tennant
Keyword(s):  
West Virginia ◽  
Experimental Testing ◽  
Field Performance ◽  
Live Load ◽  
Steel Bridge ◽  
Testing Procedures ◽  
Bending Capacity ◽  
Short Span ◽  
And Performance ◽  
Live Load Distribution

This paper is focused on the field performance of a modular press-brake-formed tub girder (PBFTG) system in short span bridge applications. The scope of this project to conduct a live load field test on West Virginia State Project no. S322-37-3.29 00, a bridge utilizing PBFTGs located near Ranger, West Virginia. The modular PBFTG is a shallow trapezoidal box girder cold-formed using press-brakes from standard mill plate widths and thicknesses. A technical working group within the Steel Market Development Institute’s Short Span Steel Bridge Alliance, led by the current authors, was charged with the development of this concept. Research of PBFTGs has included analyzing the flexural bending capacity using experimental testing and analytical methods. This paper presents the experimental testing procedures and performance of a composite PBFTG bridge.

Effect of bench terracing on ground dwelling arthropods 

2021 ◽  
Author(s):  
Liliana B Simões ◽  
Martinho A S Martins ◽  
João R L Puga ◽  
Jan J Keizer ◽  
Nelson Abrantes
Keyword(s):  
Water Infiltration ◽  
Total Abundance ◽  
Conservation Practice ◽  
Mountainous Regions ◽  
Erosion Rates ◽  
Short Rotation ◽  
Eucalypt Plantations ◽  
Spider Community ◽  
Forested Areas ◽  
To Receive

<p>Eucalypt trees are the most planted tree in the world, and in Portugal these plantations occupy 26% of the forested area. The area of Eucalypt monoculture is growing since the 50’s due to the importance of this tree for the pulp and paste industry. With short rotation cycles, it is important to facilitate the cut and transport of the logged trees. In this sense, many forested areas in mountainous regions are being terraced with bulldozers.</p><p>Terracing is a well know soil conservation practice, reducing runoff peak flows, increasing water infiltration and subsequent low soil erosion rates. Nevertheless, the impacts of terracing for eucalypt plantations are still unknown, especially in terms of biodiversity of soil fauna. Hence, to address this research gap, the present study aimed to assess the impacts of terracing on the ground dwelling arthropods in eucalypt plantations.</p><p>This study took place in a mountain slope with old eucalypt trees that were logged (May 2019) and then terraced (July) as ground preparation to receive a new eucalypt plantation. The community of ground dwelling arthropods were accessed using pitfall traps.  The arthropods were collected before the terracing process, in Spring 2019, and then seasonally after terracing until the Spring of 2020Total abundance and richness at order level, as well as, abundance, richness, Shannon-Wiener diversity and Pielou’s Evenness indexes, at Family level of Coleoptera, Araneae and Hymenoptera, were used to depict differences between pre- and post-terracing. The results showed that although terracing did not reduce the total abundance or richness, it changed the community structure. In particular, it was observed an increase in opportunist and generalist families after terracing such as Staphylinidae and Myrmicinae. The spider community also changed, with more hunter families captured after the terrace construction. In overall, the results of our study reveal that although the total abundance and richness of arthropods was not altered by the construction of terraces, their structure was modified.</p>

scholarly journals GENETIC DIVERGENCE AND MORPHO-AGRONOMIC PERFORMANCE OF JATROPHA CURCAS L. CLONES FOR SELECTION OF CLONAL VARIETIES

2016 ◽  
Vol 29 (4) ◽  
pp. 841-849
Author(s):  
ADRIANA QUEIROZ DE ALMEIDA ◽  
SIMONE ALVES SILVA ◽  
VANESSA DE OLIVEIRA ALMEIDA ◽  
DEOCLIDES RICARDO DE SOUZA ◽  
GILMARA DE MELO ARAÚJO
Keyword(s):  
Genetic Diversity ◽  
Multivariate Analysis ◽  
Plant Height ◽  
Genetic Divergence ◽  
Morphological Characterization ◽  
Stem Diameter ◽  
Agronomic Performance ◽  
And Performance ◽  
Lower Contribution ◽  
Selection Of

ABSTRACT The knowledge about genetic diversity of jatropha crop is important for genetic conservation resources and breeding of this species. The aim of this study was to evaluate the genetic diversity and performance of jatropha clones through morphological characterization to selection of clonal varieties for biofuels production. The clones were obtained through shoot cuttings from previous selection in a population of half-sibs progenies. The morphoagronomic analyses of clones was carried out at 180 days after transplantation and were evaluated plant height, stem diameter, number of primary branches and number of secondary branches, number of bunches and number of fruits per plant. Evaluating clones performance, significant results were found for the number of secondary branches. About analysis of genetic diversity, the measures of dissimilarity genetic varied from 0.62 to 13.11, this way, the UFRBPR14 and UFRBPR15 clones were more divergent. The Tocher method was efficient to verify formation of four groups. The characteristics that most contributed to the divergence among clones were branches number, height and number of bunches, and, stem diameter had lower contribution. The jatropha clones differed only in the secondary branches number and multivariate analysis showed divergence among the jatropha clones with formation of four groups. Also, branches number, plant height and number of bunches were characteristic that contributed to genetic divergence.

scholarly journals Ewe maternal behavior score to estimate lamb survival and performance during lactation

2016 ◽  
Vol 38 (3) ◽  
pp. 327 ◽  
Author(s):  
Andreia Barros de Moraes ◽  
Cesar Henrique Espírito Candal Poli ◽  
Vivian Fischer ◽  
Neuza Maria Fajardo ◽  
Marta Farias Aita ◽  
...  
Keyword(s):  
Weight Gain ◽  
Survival Rate ◽  
Maternal Behavior ◽  
Live Weight ◽  
Randomized Design ◽  
Low Weight ◽  
Completely Randomized Design ◽  
And Performance ◽  
Presence Of People ◽  
Filial Behavior

Mortality of perinatal lambs and low weight at weaning cause huge liabilities to farmers. Current study describes maternal-filial behavior and evaluates the use of maternal behavior score (MBS) to estimate the behavior of ewes and lambs soon after birth, and correlate it with lamb mortality and performance during lactation. Thirty-seven Corriedale ewes were used in a completely randomized design. MBS was assessed up to 24 hours after birth, taking into consideration the distance of the ewe from the lamb at the approach of a person. Maternal behavior, placental weight, weight gain of the lambs until weaning and their survival rate were also evaluated until two hours after lambing. More than 90% of the ewes had adequate maternal behavior, with parental care, even though ewes were very sensitive to the presence of people. There was no significant correlation between MBS and maternal behavior, lamb mortality rate and live weight gain. Under these conditions, MBS was not a useful tool to estimate maternal behavior and performance of lambs. 

scholarly journals Environmental Life-Cycle Assessment of Arable Crop Production Technologies Compared to Different Harvesting Work Systems in Short Rotation Energy Plantations

2019 ◽  
Vol 15 (2) ◽  
pp. 55-68
Author(s):  
András Polgár ◽  
Zoltán Kovács ◽  
Veronika Elekné Fodor ◽  
András Bidló
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Crop Production ◽  
Short Rotation ◽  
Environmental Life Cycle Assessment ◽  
Arable Crop ◽  
Production Technologies ◽  
Energy Plantations ◽  
The Impact ◽  
Rotation Energy

Abstract Environmental life cycle assessment (LCA) was developed as a tool for sustainable, decision-supporting environmental management. Applying agricultural sector-LCA in order to achieve both internal (comparative) and external (efficiency enhancing) benefits is a priority. Since the life-cycle assessment of products and processes attracts great interest, applying the method in agriculture is relevant. Our study undertakes a comparative environmental life-cycle assessment (LCA) of local arable crop production technologies used for the main cultivated plants: maize, sunflower, lucerne, cereals, and canola (environmental data in the territorial approach calculated on a 1 ha unit and in the quantitative approach calculated on 1 t of produce). We prepared an environmental inventory of the arable crop production technologies, constructed the life-cycle models, and executed the impact assessment. We also compiled an environmental ranking of technologies. In the impact interpretation, we compared the results with the values of short rotation energy plantations in each impact category. We analysed carbon footprints closely. The obtained results help better assess environmental impacts, climate risks, and climate change as they pertain to arable crop production technologies, which advances the selection of appropriate technologies adjusted to environmental sensitivities.

scholarly journals WINTER-SPRING NUTRITION AND MANAGEMENT EFFECTS ON EWE AND LAMB PERFORMANCE

1984 ◽  
pp. 190-198
Author(s):  
D.C. Smeaton ◽  
P.V. Rattray
Keyword(s):  
Live Weight ◽  
Grazing Management ◽  
Lactation Period ◽  
Restricted Feeding ◽  
Rotational Grazing ◽  
Short Rotation ◽  
Pregnancy And Lactation ◽  
And Performance ◽  
Carry Over ◽  
Management Effects

Aspects of the above theme were investigated in 5 trials. Trial 1 compared the effects of high and low nutrition during pregnancy and lactation on ewe and iamb production. Ewe live weight was substantially affected by nutrition treatment during pregnancy but carry-over effects on live weight at weaning were small. Nutrition during lactation strongly affected both lamb and ewe weaning weights. Ewe and lamb losses were not affected by nutrition at any stage. The results implied that ewes can be quite severely restricted on pasture during pregnancy in order to save feed for the much more important lactation period. Trials 2 and 3 investigated the management of ewes fed at maintenance levels in mid-pregnancy. The treatments consisted of various grazing durations where the ewes were shifted from one pasture break to another after a specific grazing duration, as defined by their treatment. These treatments consisted of grazing durations ranging from 3 to 56 days. Liveweight differences occurred during the 56-dav trial period but at the end there was only 2.5kg difference between extreme treatments. This suggests that where ewes are on restricted feeding during pregnancy to conserve pasture reserves, grazing duration has little consistent impact on final ewe live weight and performance. However, for several reasons, a shorter duration (3-7 days) is preferred. Trials 4 and 5 compared several winter-spring management treatments. Ewes on a 35day (short) rotation during pregnancy versus those on a 70day (long) rotation had less pasture on their farmlet at lambing (930 V. 1030 kg/ha). As a consequence the short rotation ewes were 1.5 kg lighter at weaning. Their lambs ware 2.3 kg lighter. In another comparison, set-stocking ewes 4 weeks before lambing compared with at lambing disadvantaged the ewes and lambs by 2-3 kg at weaning. The ewes set-stocked 4 weeks before lambing had consumed most of their winter reserves by lambing. In Trial 5, rotational grazing after lambing until weaning versus set-stocking, disadvantaged the ewes and iambs by 4 and 3 kg respectively at weaning. This was probably because the rotation length of 21 days in the rotational group was too long. Management implications from these results are discussed. Keywords: winter, spring, nutrition, grazing management, ewes, lambs, pregnancy, lactation, grazing duration, rotational grazing, set stocking.

Sign in / Sign up

Export Citation Format

Share Document