Dissertations / Theses: 'Pulpwood'

1

Spångberg, Kalle. "Sorting Norway spruce pulpwood /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1998. http://epsilon.slu.se/avh/1998/91-576-5616-9.gif.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Polyakov, Maksym. "Interregional aspects of timber inventory projections." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2004%20Fall/Dissertations/POLYAKOV_MAKSYM_42.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Liao, Xianchun. "Essays of forestry investments in the US and stumpage markets in the US South." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Dissertations/LIAO_XIANCHUN_33.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Persson, Erik. "Storage of spruce pulpwood : effects on wood and mechanical pulp /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6090-5.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Nilsson, Mats. "Imports of pulpwood and chips to Sweden : an economics analysis." Licentiate thesis, Luleå tekniska universitet, 1997. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17215.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Ackerman, Pierre Alexander. "An investigation into the shorthaul transport of pulpwood in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52115.

Full text

Abstract:

Thesis (MScFor)--Stellenbosch University 2001.
ENGLISH ABSTRACT: Ackerman PA. 2001. An Investigation into the Shorthaul Transport of Pulpwood in South Africa. M.Sc. in Forestry thesis. University of Stellenbosch. 178 pp Shorthaul transport also known as secondary intermediate transport (SIT), a unique feature of pulpwood transport in South Africa, is an additional transport phase within traditional secondary transport. SIT originates at a roadside landing or depot and terminates at another depot, rail siding or merchandising area (not the final destination). The reason for the addition of SIT into the transport chain is identified as the steady decline of forest road conditions to the extent that highway vehicles are unable to reach roadside landings, necessitating the use of intermediate storage sites, from where the timber is once again loaded and transported to final destination. An industry survey established that the decline of forest road conditions are related to excessively high road densities, insufficient funding for road maintenance/upgrading and the lack of understanding by landowners of the importance of maintaining forest road infrastructure. Total funding, by pulpwood companies on roads have shown an increase of R18.55 million from 1997 to 2000, however, subsequent surveys have indicated, that despite this increase in funding, the forest road conditions continue deteriorating. Of the total annual pulpwood intake of 9.39 million tonnes for 1998, 3.7 million tonnes are subject to SIT. Of this 3.7 million tonnes, 2.5 million tonnes are transported from stump to depot and 1.2 million tonnes are transported from landing to depot. The survey identified the agricultural tractor and semi-trailer as the most favoured transport system between stump or landing and depot, responsible for transporting 2.22 million tonnes annually. For 1998, manual loading and three wheel log loaders accounted for the loading of 0.6 and 2.1 million tonnes respectively of the 3.7 million tonnes subject to SIT. This survey information, assisted by newly developed terminology, was used to develop transport scenarios for the economic analysis of total cost of the different transport phases. A network analysis model and pixel-based geographic information system (GIS) were combined to analyse the various transport scenarios within three study areas in the KwaZulu/Natal Midlands, employing SIT on poor, high-density road networks. The simple pixel-based GIS contained information on the forest road network, surface cover and slopes. The results of the economic analysis highlighted the need for the reduction of road network density and for the improvement of the remaining network. This would eliminate the need for extended primary transport and allow the use of highway vehicles transporting from the compartment roadside to and past plantation exits. Results show an average annual cost penalty to the industry, by maintaining SIT, to be R43.25 million or R8.24/m3 . By not employing SIT the industry will potentially save R4.60 for every tonne of the 9.4 million tonnes consumed by the pulpwood processing plants during 1998. Key words: Network analysis. Pixel-based GIS. Timber transport. Secondary transport. Secondary intermediate transport. Secondary terminal transport. Extended primary transport. Primary transport. Dirichlet tessellations. Shorthaul. Note: Throughout this document a full stop (.) is used as a decimal separator.
AFRIKAANSE OPSOMMING: Ackerman PA. 2001.'n Ondersoek na die kortafstand vervoer van pulphout in Suid- Afrika. MSc in Bosbou tesis. Universiteit van Stellenbosch. 178 pp. sekondere intermediere vervoer (SIV), 'n addisionele vervoer-fase binne tradisionele sekondere houtvervoer, is 'n unieke kenmerk van pulphout vervoer in Suid-Afrika. SIV begin op pad, by 'n spesifieke vak of depot en eindig by 'n ander depot, syspoor of verwerkingsgebied (nie die finale bestemming nie). Aangesien die toestand van bospaaie toenemend verswak en omdat swaarpadvervoer nie langer vakke kan bereik nie, word vervoerkontrakteurs al hoe meer gedwing om van depots gebruik te maak waarheen hout deur middel van SIV vervoer moet word. Die hout word dan weer daar gelaai en na 'n verwerkingsfabriek vervoer deur middel van swaarpadvervoer. 'n Landwye opname het getoon dat die swak toestand van bospaaie toegeskryf kan word aan oormatige paddigthede, onvoldoende befondsing vir die instandhouding/ opgradering van paaie en 'n gebrek aan begrip vir die belangrikheid van die onderhoud van pad infrastruktuu r. Die totale kostes aan padverbeterings en opgraderings in die pulphout bedryf, het van 1997 tot 2000 met R18.55 miljoen toegeneem. Verdere opnames toon egter dat ten spyte van hierdie verhoging in befondsing, die toestand van bospaaie steeds onbevredigend is. Van die totale jaarlikse pulphout inname van 9.39 miljoen ton gedurende 1998, word 3.7 miljoen ton aan SIV blootgestel. Van die volume word 2.5 en 1.2 miljoen ton onderskeidelik vanaf die stomp en pad na depots vervoer. Die opname het ook landboutrekkers met leunwaens ge·identifiseer as die gewildste houtvervoer middel tussen die stomp/pad en depots. Hande-arbeid en driewielbloklaaiers is op hulle beurt verantwoordelik vir die laai van onderskeidelik 0.6 en 2.1 miljoen ton pulphout wat deur middel van SIV vervoer word. Inligting uit die opname ondersteun deur nuutgeskepte vakterminologie, is gebruik om verskillende vervoersisteme vir die ekonomiese analise van totale koste van die verskillende vervoerfases te bereken. 'n Netwerk analise model en pixel gebaseerde GIS is in kombinasie gebruik om verskillende vervoer scenarios in drie areas in Kwa-Zulu Natal te ontleed, wat gebruik maak van SIV op swak bospaaie met hoenetwerkdigthede. Die eenvoudige pixel-gebaseerde GIS het inligting weergegee oor bospadnetwerke, oppervlakbedekking en hellings. Die behoefte aan die vermindering van paddigtheid en die verbetering van bospaaie as sulks, is deur die resultate van die ekonomiese ontleding na vore gebring. Dit sal die behoefte vir uitgebreide primers vervoer uitskakel en die gebruik van tradisionele swaar padvoertuie moontlik maak. Die resultate van hierdie opname toon dat die bedryf addisioneel gemiddeld R43.25 miljoen/jaar of R8.24/m3 betaal vir die 3.7 miljoen ton wat onderhewig is aan SIV. Vir die totale 9.4 miljoen m3 het SIV die maatskappye gedurende 1998 R4.60 meer gekos vir elke m3 wat vervoer was. Sleutelwoorde: Netwerkanalise. Houtvervoer. Sekondere vervoer. sekondere intermediere verveer. Sekondere terminale vervoer. VerJengde prirnere vervoer. Kortafstand vervoer. Pixel-gebaseerde GIS Nota: In hierdie document word deurgans 'n punt (.) gebruik om desimale van heelgetalle te skei.

APA, Harvard, Vancouver, ISO, and other styles

7

Quinde, Abad Augusto. "Behaviour of the major resin- and fatty acids of slash pine (Pinus elliottii) during organosolv pulping." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30658.

Full text

Abstract:

A high extractive-content temperate conifer wood (Pinus elliottii) was examined as a pulpwood source by organosolv pulping. Particularly, the behavior of the resin- and fatty acids during the lignin solvolysis process was studied in detail. For this purpose the resin-and fatty acids were characterized in the wood, and after pulping trials in order to reveal their fate during pulping, using catalyzed 80% aqueous alcohol (methanol) as solvent. Wood extractives were removed by both methanolic cold maceration and Soxhlet extraction techniques. The resin-and fatty acid fractions thus collected were saponified and/or methylated and characterized by gas liquid chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). No significant differences were found in regard to extraction efficiencies between the two types of cold extractions. Furthermore, there was no significant difference between these two types of cold extractions in comparison with the procedure described by TAPPI standard T 204 os-76. Pulping experiments were performed at 205°C for periods of 5, 20, 40, and 60 min. Lignins, which precipitated on cooling of the black liquor (Lignin fraction I), were set aside for further extractions and chemical analyses. The molecular weight distribution of these lignins was determined by size exclusion chromatography on an HPLC and their quantity was determined either gravimetrically or volumetrically. Precipitated Lignin Fraction I, suspected of containing some adsorbed extractives and some fiber fragments, was transferred to a tared crucible. The lignin and extractives were sequentially dissolved by using tetrahydrofuran (THF), acetone and methanol. This solution was evaporated, the residue redissolved in methanol-water (80:20) and the solution liquid-liquid extracted with diethyl ether in a separatory funnel followed by methylation prior to GC and GC-MS analysis. Quantification of the resin- and fatty acids in the wood and those recovered after organosolv pulping was performed using an internal standard (methyl heptadecanoate) added prior to the extraction steps. The extractives dissolved in the black liquor were isolated by a ternary liquid-liquid extraction scheme using diethyl ether, methylated with fresh diazomethane, and the resin- and fatty acids methyl esters characterized by GC and GC-MS. The extractives present in the pulp were isolated (removed) by a Soxhlet extraction procedure with methanol and" the resin- and fatty acids fractions characterized as above. Resin- and fatty acids surviving the high-temperature pulping process, were found mainly in the black liquor. After the 60 min cook, the black liquor contained 78.1% and 71.6% of resin- and fatty acids, respectively, while the pulp retained 11.7% and 8.2%, respectively of the extractives originally present in wood. "Lignin fraction I" adsorbed 10.2% and 20.2% of the resin- and fatty acids, respectively. Contrarily, if all of the lignin is precipitated (Lignin fraction II). prior to liquid/liquid extraction of the black liquor with diethyl ether, 98% and 60.4% of the resin- and fatty acids co-precipitate with the lignin and 2.0% and 39.6%, respectively, remain dissolved in the aqueous filtrate. Industrial organosolv lignin isolated after solvent pulping of pine was thus shown to contain most (98%) of the resin acids and 39.6% of the fatty acids normally found in pines. Although not tested, it is supposed that lignins isolated by precipitation from the black liquor after organosolv pulping of other species cannot be considered as "pristine lignins" as described hitherto in the technical literature, since such lignins are heavily contaminated by the extractives of the wood species. In light of these findings all data on chemical and physical characterization of organosolv lignins and their reactivity will have to be reexamined and reassessed to remove the effect of the extractives as contaminants.
Forestry, Faculty of
Graduate

APA, Harvard, Vancouver, ISO, and other styles

8

Al, Halabi Rami. "Application of game theory in Swedish raw material market : Investigating the pulpwood market." Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39160.

Full text

Abstract:

Studien går ut på att analysera marknadsstrukturen för två industriföretag(Holmen och SCA) under antagandet att båda konkurrerar mot varandragenom att köpa rå material samt genom att sälja förädlade produkter.Produktmarknaden som undersöks är pappersmarknaden och antas varakoncentrerad. Rå materialmknaden som undersöks ärmassavedmarknaden och antas karaktäriseras som en duopsony. Detvisade sig att Holmen och SCA köper massaved från en stor mängdskogsägare. Varje företag skapar varje månad en prislista där de bestämmerbud priset föassaved. Priset varierar beroende på region. Både SCA ochHolmen väljer mellan två strategiska beslut, antigen att buda högt pris ellerlågt pris. Genom spelteori så visade det sig att båda industriföretagenanvänder mixade strategier då de i vissa tillfällen budar högt och i andratillfällen budar lågt. Nash jämviktslägen för mixade strategier räknades utmatematiskt och analyserades genom dynamisk spelteori.Marknadskoncentrationen för pappersmarknaden undersöktes viaHerfindahl-Hirschman index (HHI). Porters femkraftsmodell användes föratt analysera industri konkurrensen. Resultatet visade attproduktmarknaden är koncentrerad då HHI testerna gav höga indexvärdenmellan 3100 och 1700. Det existerade dessutom ett Nash jämviktsläge fö mixade strategier som gav SCA förväntad lönsamhet 1651 miljoner kronoroch Holmen 1295 miljoner kronor. Dynamisk spelteori visade att SCA ochHolmens budgivning följer ett mönster och att högt/lågt bud beror påavvikelser från Nash jämviktslägets sannolikhetsdistribution. Nashjämviktslägets råder ifall sannolikhetsdistributionerna vid låg budgivningär 68,6 procent för SCA och 66,7 procent för Holmen. Detta gav indikatore för icke samarbetsvilliga spel. Slutsatsen är att om två spelare (kvarnar) når
The research aims to analyze the market structure of two companies in th forest industry (Holmen and SCA) with the assumption that thes companies compete at buying raw materials and selling products. Theproduct market in this study is the paper market under the assumption thatboth companies operate in a concentrated product market. The rawmatial market that one investigates in this study is the pulpwood marketunder the assumption that it is a duopsony. What this study has concludedis that Holmen and SCA buy pulpwood from lots of different self-managingforest owners. Each company creates a monthly pricelist where they decidethe bid price of pulpwood. The amount varies depending on the region. Bot SCA and Holmen chooses between two strategic decisions, either to bid highor to bid low. Through game theory, it has been clear that each company usesmixed strategies as they sometimes give high bids and sometimes give lowbids. The Nash equilibrium for mixed strategies have been calculatedmathematically and analyzed through the dynamics of game theory. As fore market concentration, the product market has been investigatedthrough the Herfindahl-Hirschman index (HHI). Porter's five-force modelwas used to analyze the industry competition. The results showed that theproduct market is concentrated as the HHI tests gave High index scoresbetween 3100 and 1700. In addition, there existed a Nash equilibrium in amixed strategy that gave SCA expected payoff 1651 million SEK and Holmen1295 million SEK. The dynamic game theory showed that SCA and Holmen'sbidding follows a repeating trajectory and that the high/low bidding is dueto deviations from Nash equilibrium probability distribution. The Nashequilibrium situation prevails if the probability distribution at low biddingis 68.6 percent for SCA and 66,7 percent for Holmen. This providedindicators for a non-cooperative game. The conclusion is that if two players

APA, Harvard, Vancouver, ISO, and other styles

9

Vikinge, Björn. "Trädbränsleuttag i gallring /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5858-7.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Sullivan, Elizabeth Carol. "The use of advanced treatment methods for removal of color and dissolved solids from pulp and paper wastewater." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/94476.

Full text

Abstract:

This study investigated the use of activated carbon and ion exchange for the removal of color and dissolved solids from pulp and paper wastewater generated by the Union Camp Corporation mill in Franklin, Virginia. The objective of the treatment was to provide a high quality effluent suitable for direct recycling. This advanced treatment followed pretreatment by lime, alum, or ferric chloride. Required effluent quality was defined as being 5 Pt-Co units color and 75 mg/L chloride. Granular and powdered carbons, manufactured by the Westvaco Corporation, were utilized in the study. The ion exchange resin investigated was Amberlite IRA-68, manufactured by Rohm and Haas. Carbon treatment consisted of batch and column operation; ion exchange column treatment was used. The results of the study indicated that the required effluent quality was achieved by activated carbon and ion exchange treatment of wastewater that had been chemically pretreated. The most successful treatment schemes for the biotreated effluent were pretreatment with 500 mg/L alum or 2500 mg/L lime, followed by carbon column treatment for color polishing and ion exchange for chloride removal. The lime pretreated sample produced an effluent containing less than 5 Pt-Co units color as necessary for reuse, while the alum pretreated sample would require dilution with make-up water or additional treatment (i.e. ion exchange) to obtain recycle quality. The use of ion exchange for chloride removal is not practical due to the preferential exchange for sulfates. Until such time as sulfate can be eliminated from the wastewater source, other methods of dissolved solids removal should be investigated.
M. Eng.

APA, Harvard, Vancouver, ISO, and other styles

11

Olsson, Jennie. "Jämförelse av ekonomiskt utfall vid klassning av massaved enligt dagens klassningssystem och det nya systemet Prima-Sekunda : – En fallstudie på Mellanskog." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-89540.

Full text

Abstract:

In August 2019, Prima-Sekunda is about to be introduced, a new classification system for the classification of pulpwood during surveying to industry. This new classification system should be more time and cost effective and at the same time offer the industries commodity volume with better quality. The purpose of this study was to compare if there was any difference in the economic outcome with the new Prima-Sekunda compared to today's classification system when measuring pulpwood. Based on the 95 piles measured, it appeared that today's classification system gives somewhat better paid than Prima-Sekunda due to the prices for Prima-Sekunda which are initially set slightly lower than today's pulpwood price. The introduction of Prima-Sekunda should be price neutral, which means that the prices for Prima-Sekunda as shown in the current study must be reasonably equal to the current pulpwood price for this goal to be materialized.

APA, Harvard, Vancouver, ISO, and other styles

12

Meier, Jackie N. "Effects of lignosulfonate in combination with urea on soil carbon and nitrogen dynamics." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56658.

Full text

Abstract:

Lignosulfonate (LS), a by-product of the pulp and paper industry, may have the potential to increase fertilizer N availability by acting as a urease and nitrification inhibitor. Four consecutive laboratory studies were conducted to evaluate the behavior of LS in agricultural soils. The effects of various types and rates of LS on soil respiration and soil N dynamics were determined. Effects of LS in combination with fertilizers on microbial activity and N dynamics were measured. Due to the high water solubility of LS a leaching column study was conducted to determine the potential leaching of LS.
Higher rates (20% w/w) of LS initially inhibited microbial activity. Generally LS was relatively resistant to degradation by soil microorganisms and small proportions of added LS-C ($<$2.1%) were leached from the soil columns, but leaching was a function of soil and moisture regime. Recovery of added mineral LS-N from soil treated with LS was low ($<$41%). Mineral N recovered from LS plus fertilizer amended soil was higher than recovery from corresponding fertilizer treatments. Lignosulfonate reduced urea hydrolysis and the proportion of added N volatilized as NH$ sb3$-N from a LS plus urea treatment. The mineral N pool from LS plus fertilizer treated soils had significantly lower NO$ sb3$-N concentrations than corresponding fertilizer treatments. Nitrification inhibition was believed to have been due to high fertilizer concentrations. At reduced urea and LS concentrations, LS decreased NO$ sb3$-N recovery in one of four soil types. However, reduced recovery may not have been from nitrification inhibition but possibly from denitrification or chemical reactions between N and phenolics from LS.

APA, Harvard, Vancouver, ISO, and other styles

13

Malinovski, Ricardo Anselmo 1976. "Otimização da distância de extração de madeira com forwarder /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/101809.

Full text

Abstract:

Resumo: A gestão das atividades e operações ligadas à colheita de madeira carece de ferramentas computacionais que auxiliem os técnicos florestais na tarefa de redução dos custos. Em muitos casos, máquinas de elevado investimento são utilizadas na colheita de madeira sem um planejamento adequado da operação, conseqüentemente, o custo por hora dessas máquinas, que é elevado, poderia ser reduzido, caso fossem utilizados recursos tecnológicos como o Sistema de Informações Geográficas (SIG) integrado com o Sistema de Posicionamento Global, os quais, são a base da colheita de precisão. Nesta pesquisa desenvolveu-se, através de técnicas matemáticas e de funcionalidades disponíveis no Sistema de Informações Geográficas GRASS, uma ferramenta tecnológica capaz de calcular e otimizar a distância média de extração (DME) de madeira com forwarder, em diferentes tamanhos e formatos de talhões. A ferramenta desenvolvida, chamada de modelo otimizado, compartimentaliza o talhão em função da menor distância de extração. A principal variável considerada foi o alinhamento de plantio. Para testar o modelo foram considerados talhões do gênero Eucalyptus sp de uma fazenda localizada no Estado de São Paulo. Foram selecionados aleatóriamente oito talhões com formato poligonal retangular e oito talhões com formato poligonal irregular. Visitaram-se os talhões para coletar as principais variáveis (sentido de alinhamento de plantio e condições para o depósito da madeira na beira da estrada). Foram criadas, de forma teórica, dez classes de ângulos do sentido de alinhamento de plantio, sendo que um deles foi o alinhamento em nível. Com o modelo otimizado, calculou-se a DME da madeira com forwarder para todas as classes de ângulos, comparando-se com o sentido de alinhamento adotado pela empresa. Realizou-se uma simulação do custo de deslocamento do forwarder utilizando... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The management of activities and operations on the wood harvesting, does not have good computational tools to help the forest technicians with the task of cost reduction. In many cases, machines with high investment are used in wood harvesting without any adequate operation planning, consequently, the cost per hour of these machines, which is high, could be reduced, using technological resources such as the Geographic Information Systems (GIS) integrated with the Global Positioning System (GPS), which are the base of the precision harvest. In this research, a technological tool capable of calculating and optimizing the medium distance of skidding of the forwarder, in different sizes and formats of the stands, was developed through mathematical techniques and available functionalities in the Geographic Information System GRASS. The developed tools, called optimized model, divides the stand in small parts in relation to shorter distance of skidding. The main variable considered was the alignment of plantation. To test the model eucalypt stands located in the state of São Paulo were considered. Sixteen stands were randomly selected: eight with rectangular polygon form and eight with irregular polygon form. The stands were visited to collect the main variables. Ten angle classes of plantation alignment direction were theoretically created, one of them alignments was the direction of plantation following contour lines. The medium distance of skidding for all angle classes was calculated with the optimized model and was compared to the plantation alignment direction adopted by the company. The cost of forwarder dislocation was simulated using as a base the medium distance of skidding and the size of the small areas of the stand. The results showed that the optimized model developed is efficient and flexible. The stands with irregular form had a shorter medium distance of skidding... (Complete abstract click electronic access below)
Orientador: Paulo Torres Fenner
Coorientador: Helmer Schack-Kirchner
Coorientador: Jorge Roberto Malinovski
Banca: Lincoln Gehring Cardoso
Banca: Ricardo Marques Barreiros
Banca: Fernando Seixas
Banca: Julio Eduardo Arce
Doutor

APA, Harvard, Vancouver, ISO, and other styles

14

Ramantswana, Mufhumudzi Muedanyi. "A comparison of harvester productivity and stump volume waste in coppiced and planted eucalyptus grandis pulpwood compartments in the KwaZulu-Natal forestry region of South Africa." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1019844.

Full text

Abstract:

Over the past decade the South African forestry industry has gradually experienced the ramifications of labour scarcity, increases in labour costs, the effect of HIV and AIDS and increasing timber demand. Consequently, this has led to an increase in the mechanisation rate, especially in timber harvesting operations. Due to the labour challenges in South Africa, mechanised forestry equipment has increasingly been required to operate in complex forest conditions, such as coppiced compartments, where they have not operated before. It therefore occurs that harvesters are either used in certain coppiced compartments with uncertain productivity expectations, or the harvesters are not used in these compartments due to a lack of productivity knowledge. The influence that certain factors have on harvester productivity and stump volume loss – factors such as coppice regeneration practices and stem form – is poorly understood and has not been quantified. No scientific research exists regarding the effects of coppice compartments on the productivity of a harvester and the amount of stump volume waste. This research aimed at determining the influence of tree volume, tree form, stem felled first and distance between stems on the productivity of an excavator based harvester in coppiced double, coppiced single and planted Eucalyptus grandis pulpwood compartments. Furthermore, the research determined whether there was any stump volume waste, and quantified how much of it was due to excessive stump heights by the harvester. Through regression analysis, productivity equations were derived to make productivity predictions in both coppiced and planted compartments. All stumps were evaluated for waste and the average stump volume waste in coppiced double, coppiced single and planted trees was determined. The research results showed that planted trees had the highest productivity across all tree sizes, followed by coppiced single trees and then coppiced double stems. When harvesting a 0.2 m3 tree, the mean harvester productivity was 8.7 m3 per PMH in coppiced double trees, 13.8 m3 per PMH in coppiced single trees and 16.1 m3 per PMH in planted trees. In coppiced double stems the productivity was not significantly influence by the distance between stems. However, the productivity was significantly influenced by the stem felled first. The regression results showed that if the smaller stem was felled first, the productivity would increase if the larger stem’s volume was less than 0.18 m3; however where the larger stem was greater than 0.18 m3, the relationship was reversed. In addition, the productivity for both coppiced single trees and coppiced double stems were significantly influenced by stem form. The poorly formed trees had low productivity compared to the trees with good form. The stump volume findings showed that coppiced double stems had the highest average stump volume waste per stump, with 0.00307 m3 waste, followed by coppiced single trees (0.001954 m3) and planted trees (0.001650 m3). The average stump volume waste per stump with waste for the planted trees was negligible. This research provides forestry companies and harvesting contractors with information on the effect of tree volume, tree form and stem felled first on harvester productivity in E. grandis coppiced double, coppiced single and planted compartments. This information will assist in making equipment and system selection decisions and improve operational management and control. In addition, they will also be aware of stump volume losses that will occur in the three scenarios.

APA, Harvard, Vancouver, ISO, and other styles

15

Russell, Elizabeth F. (Elizabeth Fiona). "Influence of ammonium lignosulfonate fertilizer mixtures on corn (Zea mays L.) growth and nutrient composition." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61168.

Full text

Abstract:

Fertilizer P fixation and fertilizer N losses in soils may be reduced through additions of polyphenolic compounds. The influence of ammonium lignosulfonate (NH$ sb4 sp+$-LS) on triple superphosphate (TSP) efficiency was investigated in a soil incubation study using three Quebec soils and in a growth bench study using one soil. For the incubation study, soils were analyzed for pH and P extractability, as a function of NH$ sb4 sp+$-LS rate and time. In the growth bench study, TSP and NH$ sb4 sp+$-LS were applied at varying rates and corn (Zea mays L.) dry matter yields and nutrient compositions analyzed. Similar studies were conducted in subsequent growth bench studies, to evaluate combinations of NH$ sb4 sp+$-LS, diammonium phosphate (DAP), and urea on two soils.
Ammonium LS increased soluble P levels when applied with TSP. The effect was most significant in fine textured soils, and increased with time. This improved P availability to plants, without affecting growth. The optimum NH$ sb4 sp+$-LS:P$ sb2$O$ sb5$ application ratio was approximately 2.8:1. Ammonium LS did not improve availability of DAP-P in either of the subsequent experiments, nor did it improve urea fertilizer efficiency. Some NH$ sb4 sp+$-LS-urea-DAP formulations did, however, improve corn growth beyond that obtained when only urea and DAP were applied in combination. In nutrient amended soils, applying NH$ sb4 sp+$-LS DAP was detrimental to growth and, for some application rates, reduced nutrient uptake.

APA, Harvard, Vancouver, ISO, and other styles

16

Wang, Gewei. "Does market concentration motivate pulp and paper mills to vertically integrate?" Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-08242005-143103/.

Full text

Abstract:

Thesis (M. S.)--Economics, Georgia Institute of Technology, 2006.
Haizheng Li, Committee Chair ; Patrick McCarthy, Committee Member ; Vivek Ghosal, Committee Member. Includes bibliographical references.

APA, Harvard, Vancouver, ISO, and other styles

17

Landon-Browne, Ayesha. "Combined Short-lived (182W, 142Nd) and Long-lived (147Sm-143Nd) Isotope Study on Rocks from the Pulpwood-Playter Harbour Sequence (Wawa Subprovince): Constraints on the Mantle Source of Neoarchean Ferropicrites." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39573.

Full text

Abstract:

Short-lived isotope systems can be utilized to track differentiation processes that had occurred during Earth’s early history. Both the 182Hf-182W and 146Sm-142Nd systems are sensitive to silicate fractionation events due to differing parent-daughter incompatibilities. The 182Hf-182W system is also affected by metal-silicate fractionation events due to the siderophile nature of W. An increasing number of mantle-derived rocks, mainly formed during the Archean (4.0-2.5 Ga), have presented variable anomalies in the daughter products of both systems, indicating their sources contain isotope signatures established shortly after the formation of the Earth. Some Archean Fe-rich primitive magmas known as ferropicrites, have been suggested to derive from mantle domains that differentiated after the crystallization of a Hadean (>4.0 Ga) magma ocean. In order to investigate the potential involvement of a Hadean source in the petrogenesis of Archean ferropicrites, we have studied the Nd and W isotopic compositions of rocks from the Pulpwood-Playter Harbour sequence in the Wawa subprovince, Ontario, Canada. This sequence is composed of ferropicritic intrusive rocks and lavas in association with tholeiitic mafic lavas. A 147Sm-143Nd isochron including all lithologies yields an age of 2681±51 Ma (MSWD =6.6) with an initial 143Nd of +2.5. This Nd initial isotopic composition indicates the rocks were derived from a long-term incompatible-element depleted mantle source. Both the ferropicritic and the tholeiitic rocks plot on the same isochron, suggesting they derived from the same mantle source, despite their different geochemical compositions. Negative 142Nd anomalies compared to the Nd terrestrial standard were found in the majority of the rocks studied here, yielding an average μ142Nd value of -2.0±3.9. Although not resolvable from the terrestrial standard given iii the current analytical precision, the fact that almost all analysed samples exhibit negative μ142Nd values could suggest the influence of a Hadean source in their formation. If this is the case, a single early silicate fractionation event occurring between 4.56 and 4.47 Ga could explain both the ε143Nd and μ142Nd values obtained for the studied rocks. Alternatively, the involvement of eclogitic material, with a Hadean basaltic protolith, interacting with Archean peridotitic mantle could explain the Nd isotopic composition of the ferropicrites, but this would not account for the identical isotopic composition of the tholeiites – thus rendering a garnet pyroxenite source improbable. One intrusive ferropicritic sample yielded a resolvable 182W excess of +14.1 ±6.7 ppm. If this excess 182W is characteristic of the Pulpwood-Playter Harbour sequence, it indicates the decoupling of 182Hf-182W and 146Sm-142Nd systems. This decoupling could be explained by early metal-silicate fractionation recorded in the Hf-W systematics of these rocks or the contribution of Fe-rich meteoritic material into the source of ferropicrites.

APA, Harvard, Vancouver, ISO, and other styles

18

Malinovski, Ricardo Anselmo [UNESP]. "Otimização da distância de extração de madeira com forwarder." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/101809.

Full text

Abstract:

Made available in DSpace on 2014-06-11T19:31:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-09Bitstream added on 2014-06-13T19:02:01Z : No. of bitstreams: 1 malinovski_ra_dr_botfca.pdf: 1199387 bytes, checksum: e679445a3eaeb5feb0d0f50429c6c75b (MD5)
A gestão das atividades e operações ligadas à colheita de madeira carece de ferramentas computacionais que auxiliem os técnicos florestais na tarefa de redução dos custos. Em muitos casos, máquinas de elevado investimento são utilizadas na colheita de madeira sem um planejamento adequado da operação, conseqüentemente, o custo por hora dessas máquinas, que é elevado, poderia ser reduzido, caso fossem utilizados recursos tecnológicos como o Sistema de Informações Geográficas (SIG) integrado com o Sistema de Posicionamento Global, os quais, são a base da colheita de precisão. Nesta pesquisa desenvolveu-se, através de técnicas matemáticas e de funcionalidades disponíveis no Sistema de Informações Geográficas GRASS, uma ferramenta tecnológica capaz de calcular e otimizar a distância média de extração (DME) de madeira com forwarder, em diferentes tamanhos e formatos de talhões. A ferramenta desenvolvida, chamada de modelo otimizado, compartimentaliza o talhão em função da menor distância de extração. A principal variável considerada foi o alinhamento de plantio. Para testar o modelo foram considerados talhões do gênero Eucalyptus sp de uma fazenda localizada no Estado de São Paulo. Foram selecionados aleatóriamente oito talhões com formato poligonal retangular e oito talhões com formato poligonal irregular. Visitaram-se os talhões para coletar as principais variáveis (sentido de alinhamento de plantio e condições para o depósito da madeira na beira da estrada). Foram criadas, de forma teórica, dez classes de ângulos do sentido de alinhamento de plantio, sendo que um deles foi o alinhamento em nível. Com o modelo otimizado, calculou-se a DME da madeira com forwarder para todas as classes de ângulos, comparando-se com o sentido de alinhamento adotado pela empresa. Realizou-se uma simulação do custo de deslocamento do forwarder utilizando...
The management of activities and operations on the wood harvesting, does not have good computational tools to help the forest technicians with the task of cost reduction. In many cases, machines with high investment are used in wood harvesting without any adequate operation planning, consequently, the cost per hour of these machines, which is high, could be reduced, using technological resources such as the Geographic Information Systems (GIS) integrated with the Global Positioning System (GPS), which are the base of the precision harvest. In this research, a technological tool capable of calculating and optimizing the medium distance of skidding of the forwarder, in different sizes and formats of the stands, was developed through mathematical techniques and available functionalities in the Geographic Information System GRASS. The developed tools, called optimized model, divides the stand in small parts in relation to shorter distance of skidding. The main variable considered was the alignment of plantation. To test the model eucalypt stands located in the state of São Paulo were considered. Sixteen stands were randomly selected: eight with rectangular polygon form and eight with irregular polygon form. The stands were visited to collect the main variables. Ten angle classes of plantation alignment direction were theoretically created, one of them alignments was the direction of plantation following contour lines. The medium distance of skidding for all angle classes was calculated with the optimized model and was compared to the plantation alignment direction adopted by the company. The cost of forwarder dislocation was simulated using as a base the medium distance of skidding and the size of the small areas of the stand. The results showed that the optimized model developed is efficient and flexible. The stands with irregular form had a shorter medium distance of skidding... (Complete abstract click electronic access below)

APA, Harvard, Vancouver, ISO, and other styles

19

Nordvall, Hans-Olof. "Studies on market analysis of forest-based products /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5621-5.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Gunnarsson, Björn. "Underröjningsgradens påverkan på förstagallringsnetto med flerträdsaggregat." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-40691.

Full text

Abstract:

I Sverige finns ca 1,2 miljoner hektar skog som bedöms ha omedelbart röjningsbehov. Skog där röjningen uteblir eller är svag kan komma att klassas som konfliktbestånd. I konfliktbestånd är stammarna många och diameterspridningen stor och dessa kan då behövas underröjas innan gallring. I denna studie jämfördes produktionen, kostnaderna och intäkterna från fyra olika underröjningsbehandlingar, oröjd, siktröjt, röjt allt upp till 5 cm i brösthöjd och röjt allt upp till 7 cm i brösthöjd. Behandlingen oröjd gav det bästa nettot och sämst hade upp till 5 cm efter gallring och uttransport av virke. En anpassad eller svag röjning gav lägre totalkostnader jämfört med ingen eller hårdare röjning.
In Sweden there are about 1,2 million hectares of forest with immediate need of pre-commercial thinning. Stands, where conducted pre-commercial thinning are light or even absent, become tight with thin stems. In such stands pre-commercial thinning before first thinning may be required, due to operational advantages such as increased visibility. This study compared production, cost and revenues from four different pre-commercial thinning treatments: no pre-commercial thinning, sight pre-commercial thinning, cleared everything up to 5 cm diameter at breast height and cleared everything up to 7 cm diameter at breast height. The treatments whit no pre-commercial thinning had best net value and worst had up to 5 cm. A custom or weak pre-commercial thinning give a lower total cost compared to no or harder pre-commercial thinning.

APA, Harvard, Vancouver, ISO, and other styles

21

Dias, Rafael Antunes. "Padrões de diversidade em comunidades de aves relacionadaos a varáveis de habitat em campos temperados do sudeste da América do Sul." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/72388.

Full text

Abstract:

Indivíduos, populações e espécies tendem a usar e selecionar habitats de modo não-aleatório. Consequentemente, a perda e a degradação de habitats geram impactos distintos sobre os organismos dependendo de seus atributos. Os efeitos da perda de habitat são claros – os organismos são eliminados ou desalojados por falta de habitat ou baixo sucesso reprodutivo. As consequências da degradação de habitat são mais sutis, e resultam na incapacidade de um ecossistema sustentar determinadas espécies. Como a perda e a degradação de habitat reduzem a disponibilidade de nichos, espera-se que táxons ecologicamente especializados e com requerimentos estreitos de nicho sejam mais propensos à extinção que generalistas. Organismos que são negativamente afetados por perda e degradação de habitat em geral exibem porte muito grande ou muito pequeno, baixa mobilidade, baixa fecundidade, reduzido recrutamento e estreitos requerimentos de nicho. Campos temperados constituem ambientes particularmente afetados por perda e degradação de habitat. No sudeste da América do Sul, como em muitas outras regiões do planeta, a expansão da agricultura e silvicultura são os principais responsáveis pela perda de habitat campestre. Os remanescentes de vegetação natural são usados para criação de gado, estando sujeitos à degradação pelo sobrepastejo, pisoteio e técnicas de manejo. Avaliar como a perda e degradação de habitat afetam a diversidade de organismos campestres é vital para o desenvolvimento de estratégias de conservação e manejo. A presente tese tem por objetivo investigar como a degradação e perda de habitat induzidas pela pecuária e silvicultura afetam a diversidade e a composição das comunidades de aves. Inicialmente, exploramos as relações entre variáveis de habitat e a composição da comunidade de aves num gradiente de altura da vegetação determinado por pastejo em campos litorâneos do Rio Grande do Sul. Posteriormente, avaliamos como variações no relevo interagem com variáveis de habitat e afetam a diversidade de aves em áreas de pecuária na Campanha gaúcha. Finalmente, avaliamos de que forma a perda de habitat resultante do estabelecimento de plantações industriais de celulose em áreas de campo afeta a composição de comunidades de aves campestres. Nossos resultados demonstram que a degradação de habitat decorrente do manejo de gado em campo nativo afeta a comunidade de aves de forma diferencial. Aves adaptadas a campos ralos ou generalistas tendem a ser beneficiadas pelo pastejo, ao passo que as espécies associadas à vegetação alta e densa são desfavorecidas. As variações na topografia reduzem os impactos da degradação de habitat nos campos. Essas variações interagem com o habitat e afetam de forma diferencial os distintos componentes da diversidade. Por outro lado, a perda de habitat decorrente da silvicultura gera um impacto de maior magnitude, alterando a composição das comunidades de aves e favorecendo aves não-campestres. Nesse contexto, impedir que novas áreas de campo nativo sejam convertidas em plantações de árvores passa a ser imperativo. Embora o manejo do gado aumente a diversidade em nível de paisagem ao criar um mosaico de manchas de vegetação de alturas distintas, maior atenção deve ser dada à manutenção e recuperação de formações densas de herbáceas de grande porte. Isso somente pode ser assegurado através de mudanças no regime do pastejo ou do desenvolvimento de técnicas de manejo alternativas.
Individuals, populations and species tend to select habitats in a non-random way. Consequently, habitat loss and degradation will have different impacts on organisms according to their traits. The effects of habitat loss are straightforward – organisms are eliminated or displaced because of the inexistence of adequate habitat or of low breeding success. Effects of habitat degradation are more subtle and result in the reduction of the capacity of an ecosystem to support some subsets of species. Since habitat loss and degradation reduce niche availability, ecologically specialized taxa with narrow niche requirements are expected to be more extinction prone than habitat generalists. Temperate grasslands have been strongly impacted by habitat loss and degradation. In southeastern South America, the expansion of agriculture and industrial pulpwood plantations are the main sources of habitat loss. Remnants of natural grassland vegetation are used for livestock ranching, being subject to habitat degradation from overgrazing, trampling and inadequate management techniques. The evaluation of how habitat loss and degradation affect the diversity of grassland organisms is vital for the development of management and conservation techniques. The main goal of this thesis is to evaluate how habitat degradation and loss related to cattle ranching and pulpwood plantations affect the diversity and composition of bird communities. We began by exploring the relationship between habitat variables and the composition of the bird community along a gradient of vegetation height determined by grazing in coastal grasslands of the state of Rio Grande do Sul. We then assessed how variations in the relief interact with habitat variables e affect the diversity of birds in rangelands of the Campanha gaúcha. Finally, we evaluated how habitat loss related with grassland afforestation for pulpwood plantations affects the composition of grassland bird communities. Our results demonstrate that habitat degradation resulting from livestock ranching in natural grasslands affects bird communities in a differential way. Birds adapted to stunted grasslands or habitat generalists tend to benefit from grazing, whereas tall-grass specialists are negatively affected. Variations in topography are responsible for reducing the impacts of habitat degradation in grasslands. These variations interact with habitat and have a differential effect on distinct components of diversity. On the other hand, the magnitude of the impact of habitat loss from afforestation is larger, altering the composition of bird communities and favoring a series of non-grassland species. In this sense, protecting remaining grasslands from afforestation is imperative. Although cattle ranching increases diversity at the landscape level by creating a mosaic of vegetation patches of different height, more attention should be given in maintaining and recovering dense formations of tall grassland plants. This can only be achieved by changing grazing regimes or developing alternative management techniques.

APA, Harvard, Vancouver, ISO, and other styles

22

Richardson, DE. "Derivatisation techniques for the analysis of resin acids in pulp and paper industry effluent using high performance liquid chromatography." Thesis, 1987. https://eprints.utas.edu.au/21383/1/whole_RichardsonDesmondEric1989_thesis.pdf.

Full text

Abstract:

The environmental significance of resin acids originating from pulp and paper industry effluent has led to a detailed investigation of techniques used for their analysis. The chromatographic separation of a number of resin acids (based on those found in Pinus radiata) and their coumarin derivatives was investigated using High Perform- ance Liquid Chromatography (HPLC) with a view to developing a sen- sitive quantitative technique for analysis of total resin acids in pulp and paper industry effluent and in waterways receiving those effluents. Seven resin acids (sandaracopimaric, isopimaric. levopimaric, palust- ric, dehydroabietic, abietic. and neoabietic acid) were reacted with 4-bromomethyl-7-methoxycoumarin (4BrMMC) or 4-bromomethyl-7-acetoxy- coumarin (4BrMAC) to form (7-methoxy-coumarin-4-yl)methyl (MMC) esters and (7-acetoxy-coumarin-4-yl)methyl (MAC) esters respectively. The molar absorptivity of the resin acid MMC esters at 318 nm was shown to be the same for each resin acid ester, thus making it poss- ible to measure them quantitatively by HPLC even though they were not all chromatographically separated. Fluorescence quantum yield meas- urements of the MMC esters however showed a variation in fluorescence response that depended on the resin acid. There was also a variation in fluorescence quantum yield with solvent and water content of the solvent. These two factors precluded the use of the fluorescent properties of the MMC esters for quantitative analysis. Like the MMC esters, the molar absorptivity of the resin acid MAC esters was the same for each resin acid ester, thus enabling use of the chromophore at 310 nm for quantitative analysis. The resin acid MAC esters possessed no fluorescence. but reaction with alkaline methanolic solution was shown to hydrolyse the acetoxy group of the coumarin compound while maintaining the ester linkage to the resin acid. Fu1the1more the fluorescence response of each of the seven resin acids was the same in alkaline media. In the course of these studies, both 4BrMMC and 4BrMAC were found to decompose rapidly when exposed to light with up to half the reagent decomposing in only 30 minutes. The consequences of this photolabil- ity were explored to ascertain the probability of reactions with resin acids during the derivatisation reaction. Similar decomposit- ion products were observed for both coumarin compounds. In the presence of oxygen. 4-methyl-. 4-formyl-. 3-bromo-4-methyl-, and 3-bromo-4-formyl- derivatives of both methoxy and acetoxy coumarin were formed. In the absence of oxygen. and using a high intensity mercury discharge lamp light source. 4BrMMC was shown to produce 4-methyl-, and 3-bromo-4-methyl-7-methoxycoumarin as well as a photo- dimer. The latter two compounds eluted after the 4BrMMC peak thus posing a potential inte1ference problem for HPLC analysis. It was concluded that for the purposes of the analytical technique, it was important to protect solutions containing the coumarin derivatisation reagent from light during all stages of the derivatisation process apart from volumetric transfer of solutions. Derivatisation procedures rep01ted in the literature for similar types of reactions rely on the use of heat and crown ether catalysts to achieve rapid quantitative derivatisation. The effect of tempera- ture, crown ether catalyst, solvent and ratio of derivatisation reagent to resin acid were studied. Quantitative conversion to both the methoxy- and acetoxy-coumarin esters was obtained at room temp- erature, without catalyst. in either acetonitrile or acetone in I 0-15 mins., provided a 10-20 molar excess of derivatisation reagent was present. Application of the technique to extracts from water samples contain mg a variety of other organic compounds and resin acid concentrate- ions was pursued. Apart from the coumarin derivative of dehydroa- bietic acid. all of the resin acid coumarin esters studied co-eluted on a C-8 reverse phase HPLC column. A gradient elution programme based on acetonitrile and water was optimised to obtain adequate resolution of the resin acid coumarin esters from other components present m the effluent extracts. The method was applied to the analysis of resin acids in a river estuary into which pulp and paper effluent was discharged. Based on extraction of 100 ml samples. a detection limit of 0.005 mg C1 was calculated for the technique using 4BrMMC as the derivatisation reagent and UV absorption for detection. A detection limit of 0. OOO 1 mg C 1 was calculated for the techniques using 4BrMAC with fluorescence detection of the hydrolysed ester derivative. The lower detection limit associated with 4BrMAC esters offers a significant improvement over current gas chromato- graphy methods using flame ionisation detection.

APA, Harvard, Vancouver, ISO, and other styles

23

Schütte, Craig Ernst. "Unlocking the code to hardwood pulpwood supply : an analysis to determine if intervention in the stump-to-mill supply chain by NCT will increase hardwood pulpwood supply from its members in KwaZulu-Natal?" Thesis, 2006. http://hdl.handle.net/10413/3826.

Full text

Abstract:

NCT Forestry Co-operative Limited has experienced decreased yearly hardwood pulpwood volume sales over the last several years. This indirectly means NCT members have decreased their hardwood pulpwood volume trade to NCT over the last several years. Combined with the general under-supply of hardwood pulpwood from its members, NCT's current systems do not accurately predict the monthly and yearly volumes from its members. This is because many factors play a role and influence the physical volume of hardwood pulpwood supplied during the marketing process from the stump to the mill. Two independent studies have been carried out by NCT, to determine the main factors causing NCT members to under-supply their hardwood pulpwood. Both reports sighted "price" as the major factor and driver in contributing to NCT members making a decision to bank their timber or dispose of it elsewhere. Due to NCT's core business being export orientated, "price" is considered to be "exogenous" by nature or defined as an "uncontrollable variable" as the mill delivered price NCT offers its members is a factor of the macro economic conditions between South Africa, United States of America and Japan. More specifically the "price" NCT offers its members is a factor of the exchange rate between the South African rand and the United States dollar. The second contributing factor which was sighted by NCT members as to why they were under-supplying their hardwood pulpwood was "operational issues". "Operational issues" can be refined to issues pertaining to the stump-to-mill supply chain. "Operational issues" as apposed to "price" can be considered as a "controllable variable" as every component within the stump-to-mill supply chain can be controlled and managed. This paper specifically undertakes to investigate, in more detail, what specific factors within the stump-to-mill supply chain are causing NCT members to under-supply their hardwood pulpwood to NCT. Mitigating research into the stump-to-mill supply chain as an area of concern for NCT is the fact that South Africa is currently and forecasted for the future, to have an under-supply and over-demand of hardwood pulpwood. This factor alone has many knock-on effects within the entire forestry value chain. Combined with the under-supply and over-demand situation for hardwood pulpwood, is the fact that NCT's competitors define the profile of an NCT member, being mainly associated to the medium and small grower category, as the most liquid form of hardwood pulpwood resource available. By understanding the problems the contracting fraternity faces in the value chain, further mitigates the focus on the stump-to-mill supply chain as a problem area for NCT. Research exposes that mainly "second economy" or "informal contractors" work in the environment of medium and small grower categories. For independent contractors, this environment is characterized by failure to reach economies of scale, lack of business skills, poor access to finance and training, difficulties in getting public liability insurance cover and limited help from the large corporate grower organisations. In general, NCT members falling into the medium and small grower categories will invariably experience un-professional service from independent contractors. This causes conflict in the stump-to-mill supply chain and can damage the marketing service NCT provides to its members and markets. The loyalty of NCT hardwood pulpwood owning members will be tested as the sale of hardwood pulpwood moves more and more into a "sellers" market, which will inherently mean an increase in the bargaining power and leverage these members will enjoy. Buyers who position themselves to satisfy these anticipated increased needs of private/independent growers will most likely enjoy competitive advantage. This study has found that competitive advantage partly lies in more control and management of the stump-to-mill supply chain. The study has also recommended that NCT adopt a combined strategy of backward vertical integration with keiretsu (a combined supply chain management strategy that incorporates few suppliers and backward vertical integration in a coalition partnership) in its approach to gain more control of the stump-to-mill supply chain. The study further concluded that the orthodoxy of supply chain management (SCM) emphasises competitive advantage through increased operational control and efficiency combined with market responsiveness from production and distribution processes into the hands of NCT. Further, the paper found that anticipated future competition for NCT would be between the stump-to-mill supply chains rather than between firms. Indirectly this means NCT will have to increase the scope of service to its members and that means increasing its service in the stumpto-mill supply chain. An effective hardwood pulpwood procurement (marketing) strategy rolled out by NCT using a combination of backward vertical integration and keiretsu as supply chain management strategies, in a drive to gain more control and management over the stump-to-mill supply chain was strongly recommended. This strategy will not only increase the control over the volume supplied to NCT but will also increase the sustainability of fibre by creating planned felling schedules. This strategy will also provide a stable environment for the "informal" or "second economy" contractors to work in, while satisfying the increasing needs of NCT members, and in the process creating a competitive advantage by providing a much-needed additional service. By adopting the supply chain management approach of using both backward vertical integration and keiretsu as strategies will allow for benchmarking between the two strategies to take place, while at the same time due to increased planning, economies of scale will be achieved leading to cost savings. Cost savings in the stump-to-mill supply chain will allow NCT more flexibility in defending its mill delivered prices. Hence, the key to unlocking the code to hardwood pulpwood supply from the NCT membership partly lies in the intervention of the stump-to-mill supply chain by adopting a dual supply chain management strategy of both backward vertical integration and keiretsu by NCT in the stump-to-mill supply chain. However, one can capture the hill by using "service" only, but this strategy will not necessary help you hold the hill. A combined strategy of "price" and "increased service" will more than likely allow NCT to capture and hold the hill.
Thesis (M.B.A.) - University of KwaZulu-Natal, Pietermaritzburg, 2006.

APA, Harvard, Vancouver, ISO, and other styles

24

Naidoo, Lenny. "Wood chip exports and the challenges faced by private pulpwood farmers in Southern KwaZulu-Natal." Thesis, 2011. http://hdl.handle.net/10413/6394.

Full text

Abstract:

The South African forestry industry has contributed significantly to the economic growth of the country by the planting of trees and the processing of these trees for the export market. With the increased demand for wood chips, the wood chip industry is concerned that the plantation resource that is currently available may not be adequate to fulfil the production required for future wood chip export. The purpose of this study is to examine the trends in wood chips exports from the Port of Durban and to examine the stability and growth of private pulpwood production in Southern KwaZulu-Natal. The forestry pulp and paper sector and its related downstream manufacturing enterprises is an important part of the KwaZulu-Natal economy. Eucalyptus and wattle timber are used to manufacture pulp and are exported in the form of wood chips. The Durban Wood Chipping facility is aimed at the export of wood chips from Durban to pulp and paper manufacturers in Japan. The methodology used in this study included questionnaires and semi-structured interviews that were held with the respondents involved in the forestry industry. A questionnaire was sent electronically to 119 participants being the total population of timber farmers that supply NCT Durban Wood Chips. A total of 33 respondents completed the questionnaire resulting in a 27.73% response rate. Three key personnel, with a strong forestry background, belonging to NCT Forestry Cooperative limited were selected as participants for the qualitative aspect of the study. The findings of the study showed that wood chips exports have increased from the Durban facility between 2006 and 2011. This came from recent research literature as well as data from NCT Durban Wood Chips (PTY) LTD. Dominant challenges faced by the farmers were land reform, transportation costs and municipal rates. Land claims, road infrastructure, economics (cost vs income) and demand for timber were the most challenging factors affecting private timber production into the future. The qualitative and quantitative results confirm that timber production is definitely increasing and hence contributing to stability of private pulpwood production in Southern KwaZulu-Natal.
Thesis (MBA)-University of KwaZulu-Natal, Westville, 2011.

APA, Harvard, Vancouver, ISO, and other styles

25

Trømborg, Erik. "The global pulpwood market implications of changes in economic growth, timber supply, and technological trends /." 1997. http://catalog.hathitrust.org/api/volumes/oclc/38447102.html.

Full text

Abstract:

Thesis (M.S.)--University of Wisconsin--Madison, 1997.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 41-45).

APA, Harvard, Vancouver, ISO, and other styles

26

Woodworth, Jillian Gay. "Sublethal effects of Eucalyptus-based pulp mill effluents on Tasmanian native fish." Thesis, 1998. https://eprints.utas.edu.au/22009/1/whole_WoodworthJillianGay1998_thesis.pdf.

Full text

Abstract:

The effects of eucalypt-based pulp mill effluent on organisms in marine receiving waters are relatively unknown. A previous study by Munday et al. (1991) assessed the acute toxicity of the effluent discharged from Australian Paper's Burnie pulp and paper mill. However, at that time the mill was discharging up to 20% pine-based effluent. To obtain an accurate assessment of the current situation at the mill, which is now processing 100% eucalypt pulp, the acute toxicity of the Burnie mill effluent to Vibrio fisheri, Isochrysis galbana, Tetraselmis suecica, Nitzschia closterium and Artemia salina was calculated. The acute toxicity of the effluent to microalgae was determined for two reasons; microalgae form the base of the food chain and has been shown to be sensitive to simulated eucalypt-based pulp mill effluent (Stauber et al. 1994), also, as the microalgae formed the base of the food chain in the experiments discussed in Chapter 3, the sensitivity of the microalgae and the Artemia, which fed on the microalgae, to the effluent needed to be assessed. The results obtained were related to the constituents of the effluents with the main toxic property of the effluents being the pH. After the pH had been modified to that of seawater the effluents were less toxic. The effluents were not acutely toxic to single cell algae at the concentrations discharged into Bass Strait. When evaluating the effects of complex effluents such as eucalypt-based kraft pulp mill effluent the different routes of exposure must be considered. The contribution of dietary exposure as well as waterbome exposure needs to be taken into consideration as there has been much discussion in the literature about the extent of the influence of food chain bioaccumulation. To determine the significance of each route of exposure, and if any additive or synergistic effects of the routes occur, an experiment was designed to simulate effects of Burnie mill effluent in the environment. Common jollytails (Galaxias maculatus) were exposed to low levels (0.5%) of effluent via the food chain or via the water column or both food chain and water column. As biotransformation of toxicants occurs in the liver, this organ was analysed to detect any sublethal effects which may have been caused by exposure to the effluent. Significant increases in EROD ( ethoxyresorufin-0-deethylase) activity in fish exposed to the effluent by the combined routes were detected. However, no significant differences in EROD activity occurred between control fish and fish exposed to the effluent by only one route. The effects of the combined routes of exposure appeared to be synergistic rather than additive as a 3 - 4 fold increase in EROD activity was found in fish exposed to the effluent via both routes. This was supported by the increase in histological changes within the livers of fish exposed by the combined routes. Also, proliferation of rough endoplasmic reticulum within the hepatocytes of these fish as determined by transmission electron microscopy was an additional indicator of a sublethal response in fish receiving the effluent by the combined water column and dietary routes. An indirect ELISA to detect the presence of cytochrome P-4501A1 was performed but this method was not sensitive enough to detect effects of effluent exposure. As exposure to pulp mill effluent can have adverse effects on the livers of fish it follows that the reproduction of the fish may be affected, as this organ is involved in hormone metabolism essential to the reproductive processes. To evaluate this aspect of the sublethal effects of pulp mill effluent, Tasmanian blennies were collected from locations in Emu Bay then transferred to the University and maintained in equivalent concentrations of pulp mill effluent to those found in Emu Bay. The blennies then spawned and the resulting embryos were also maintained in the same effluent concentrations until hatching. The exposed blenny larvae were compared with control larvae and showed a significant decrease in length. The number of larvae per spawn and the quality of eggs was also significantly less in Emu Bay fish than control fish. No significant differences between the Emu Bay sites were found so that the incidence of sublethal effects in blenny larvae was not related to distance of blenny populations from the mill outfall. From the results of this series of experiments, simulating environmental exposure to the Burnie mill effluent, as discharged during 1994 - 96, it can be stated that levels of the effluent equivalent to those occurring in Emu Bay cause fish to exhibit minor changes in liver structure and ultrastructure, a slight increase in detoxification enzyme activity and a decrease in embryo / larval growth. These changes apparently do not severely affect the health of the fish. However, the effect of the effluent on reproduction is appreciable and would have a potential impact on the fish population dynamics.

APA, Harvard, Vancouver, ISO, and other styles

27

Blackburn, DP. "Improving Eucalyptus nitens for sawn-board, veneer and paper products." Thesis, 2012. https://eprints.utas.edu.au/12934/10/Blackburn_whole_thesis_ex_pub_mat.pdf.

Full text

Abstract:

Eucalyptus nitens is widely planted for pulpwood, and increasingly also for solid-wood timber products, in cool-temperate climates. This thesis investigated the potential of tree breeding to improve the properties of E. nitens grown for sawn boards, pulpwood and veneer products. Two studies were undertaken using a 14 -15 year old E. nitens provenanceprogeny trial established in Tasmania and comprising 420 open-pollinated families collected from three native races. In the first study, methods were developed to track the identities of 560 pedigreed trees through harvesting, transportation and sawmill processing. A second study tracked 548 trees from the same trial through a rotary peeled veneer production system. Genetic parameters were estimated for a total of 20 tree, log and wood traits relevant to sawn board, veneer and pulpwood products. Genetic differences among races of E. nitens were significant in wood stiffness, growth, stem form and pulpwood traits, but not significant for log end-splitting and sawn board checking traits. The Southern race had the most favourable mean values. Significant additive genetic variation within races was observed in all traits except log-taper, demonstrating that the quality of plantation-grown E. nitens wood products could be improved through breeding. Strongly positive genetic correlations among diameter at breast height (DBH) at ages 4, 9 and 14 years and between DBH all ages and the traits survival, log volume and stem straightness, demonstrated that early-age selection for DBH would not compromise stem straightness and would improve product volume recovery. Log end-splitting was under moderate genetic control but there was a negative genetic correlation between end-splitting and solidwood product volume.Sawn board and veneer sheet stiffness was highly heritable, and strongly correlated with acoustic wave velocity (AWV), measured in standing trees and logs. Consistent with previous studies in E. nitens, wood basic density, near infra red-(NIR) predicted kraft pulp yield (KPY) and cellulose content (CC) had moderate-to-high heritabilities, although coefficients of additive genetic variation for these traits were small. Estimated genetic correlations between standing tree AWV and each of the traits veneer sheet modulus of elasticity (MOE), sawn-board MOE, KPY, CC and basic density were highly significant and strongly positive, suggesting that standing tree AWV could be adopted as an indirect non-destructive selection criterion for improving solid-wood product stiffness, while simultaneously improving wood chemical traits favoured by the pulpwood industry. Basic density had no significant genetic relationship with KPY and CC, although other studies have reported moderate to strong significant values. Surface and internal checking in sawn boards, which are important defects leading to value downgrade, were shown to be under moderate levels of additive genetic control. Internal checking in wedges cut from log disks and in wafer sections cross-cut from processed boards were strongly and positively genetically correlated. However, the genetic correlation of checking traits with density and AWV were generally not significant. Work presented in this thesis clearly demonstrates the potential for genetic improvement of E. nitens for pulpwood, sawn-boards and veneer production. A new method of tracking trees in processing studies has been established. Methods for assessing checking have been developed, and the utility of nondestructive AWV and NIR techniques has been confirmed for use in E. nitens breeding programs, aiming to simultaneously improve the quality and recovered volume of pulpwood and solid-wood products.

APA, Harvard, Vancouver, ISO, and other styles

28

Sonnenfeld, David Allan. "Greening the tiger? social movements' influence on adoption of environmental technologies in the pulp and paper industries of Australia, Indonesia, and Thailand /." 1996. http://catalog.hathitrust.org/api/volumes/oclc/38016047.html.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Perry, Michelle. "An examination of the variables that influence the supply of Eucalyptus pulpwood timber to NCT strategic markets in KwaZulu-Natal." Thesis, 2006. http://hdl.handle.net/10413/991.

Full text

Abstract:

In recent times a need has developed within NCT for a more accurate prediction of pulpwood available from its members for supply to strategic markets. Present systems indicate the volume of timber per member per farm, however this volume has been found not to be an accurate prediction of what will actually reach the mill at the end of the day as many factors come into play and influence the volume that reaches the mill. The questions arise: which factors influence the availability of marketable Eucalyptus pulpwood timber, and to what extent do the different factors play a role? It was with this problem in mind that a comprehensive survey was undertaken to evaluate a number of factors identified and to try and determine their impact on the volume of Eucalyptus pulpwood supplied.
Thesis (M.B.A.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

APA, Harvard, Vancouver, ISO, and other styles

30

McEwan, Andrew Mark. "The effect of tree and bundle size on the productivity and costs of cut-to-length and multi-stem harvesting systems in Eucalyptus pulpwood." Diss., 2012. http://hdl.handle.net/2263/31119.

Full text

Abstract:

There is currently a global increase in Eucalyptus pulpwood plantations. Harvesting systems traditionally utilised in the northern hemisphere are being used in Eucalyptus pulpwood plantations worldwide. However, the small tree size and complexity of debarking Eucalyptus have provided harvesting with productivity and cost challenges not previously experienced in northern-hemisphere conditions. Much research has been invested in these two harvesting methods in northern-hemisphere species and conditions. There is little research available on mechanised processing-machine productivity and costs in Eucalyptus. This investigation aimed to quantify the effect that tree and bundle size has on the productivity of different processing machines in Eucalyptus plantation pulpwood. This was done through regression analysis, whereby productivity models that included tree size and bundle size were constructed. The research also aimed to determine whether or not the multi-stem systems were more cost-effective in smaller tree sizes. The research investigated five mechanised harvesting options that forestry managers could use in Eucalyptus pulpwood plantations. These systems consisted of one CTL system, one full-tree system with single-stem processing and three full-tree systems with multi-stem processing. The CTL system used a harvester to process the trees into logs and to extract them. The full-tree system with single-stem processing used a dangle-head processor (DHP) to process trees into logs. The first full-tree system with multi-stem processing used a chain-flail debrancher debarker (CFDD) to produce debarked and debranched tree lengths, which were slashed into logs. The remaining full-tree, multi-stem systems both produced chips. The first used a chain-flail debrancher debarker chipper (CFDDC) and the second, a CFDD feeding into a stand-alone disc chipper (CFDD&C). The productivity data, measured as m3 per productive machine hour (PMH), was then statistically analysed using regression techniques. Productivity equations were formulated, considering tree size and bundle size, as well as the quadratic functions of these two variables and the interaction between them. Bundle size was only applicable to the multi-stem processing machines. The productivity equations successfully predicted processing-machine productivity, using tree size and bundle size as input variables. Apart from the 0.075 m3 tree size class, the CFDD had the highest overall productivity. The costs of the five systems were then calculated for different tree sizes. No single system was more cost-effective than the others across all tree sizes. In 0.075 m3 trees, the CFDDC system proved the most cost-effective. All systems evidenced high costs in the 0.075 m3 trees, ranging between $19.43 per m3 for the CFDDC system to $28.84 for the harvester system. In 0.40 m3 trees, the cost differences between systems were lower, ranging from $6.91 per m3 for the DHP system to $11.84 per m3 for the CFDD&C. This study confirms that the CTL system was very expensive to operate in the small tree sizes (0.075 m3). There is a cross-over point at 0.25 m3 per tree, where the CTL system costs become lower than those of the full-tree system. At the 0.40 m3 tree size, the full-tree system is slightly more expensive than the CTL system. Copyright
Dissertation (MSc)--University of Pretoria, 2012.
Plant Production and Soil Science
unrestricted

APA, Harvard, Vancouver, ISO, and other styles

31

Van, Deventer Francois. "A quantitative study on growth, basic wood density and pulp yield in a breeding population of Eucalyptus urophylla S.T. Blake, grown in KwaZulu-Natal." Thesis, 2008. http://hdl.handle.net/10413/2627.

Full text

Abstract:

The first objective of this study was to evaluate Eucalyptus urophylla S.T. Blake provenances in terms of their growth, basic wood density and pulp yield properties. The second objective was to determine the genetic and phenotypic associations that may exist between growth, basic wood density and pulp yield. Data of 9022 open-pollinated progenies representing 306 families, collected from 17 provenances, were used to evaluate growth. To evaluate basic wood density and pulp yield, as well as the genetic and phenotypic associations between the three traits, data of 300 open-pollinated progenies representing 30 selected families from 11 provenances were used. Narrow-sense heritabilities for all three traits were estimated from data collected in a single E. urophylla provenance/progeny trial planted in northern KwaZulu-Natal. The results showed that significant provenance effects for growth, basic wood density and pulp yield were observed. Heritability was found to be strong for basic wood density (h2 = 0.51) and moderate to weak for volume growth and pulp yield (h2 = 0.17 and h2 = 0.11, respectively). This suggests that big genetic gains can be achieved for basic wood density. Although the heritability estimates for volume growth and pulp yield were weaker, this still allows for tree breeders to make significant genetic gains through accurate selection from this E. urophylla breeding population. Genetic and phenotypic associations between the three traits were estimated from data collected in the same trial. The genetic correlation between volume growth and pulp yield was positive and moderately strong (rA = 0.66). The genetic correlation estimate between volume growth and basic wood density was found to be negative but weak (rA = -0.08). The genetic association between pulp yield and basic wood density was found to be positive but weak (rA = 0.17). Correlation estimates between volume growth and basic wood density, as well as between pulp yield and basic wood density produced standard errors greater than the correlation itself (s.e. = ± 0.32 and ± 0.22, respectively). These high standard errors, coupled with weak genetic correlations, suggest that these correlation estimates are non-significant, but are probably a result of utilizing a small sample size. However, these correlations have a value in making breeding choices, if treated with caution. Key words: Eucalyptus urophylla, provenance, growth, basic wood density, pulp yield, heritability, genetic correlation
Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Pulpwood'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles