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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development of Bark-based Environmental-friendly Composite Panels

Gupta, Gireesh Kumar 19 January 2010 (has links)
Due to increasing shortage of wood supply and higher environmental concerns with the depletion of forest resources, in recent years, there is a strong interest in using forest and agricultural residues for development of value added products. Bark is a mill-waste residue, available in plenty, having limited uses and causing disposal problems. Bark possesses a large amount of phenolic compounds, which can act as an adhesive in making panels, however only limited research has been done in this area. The main objective of this project is to develop bark-based environment-friendly panels with and without synthetic resins, using mountain pine beetle infested lodgepole pine barks. Analysis of bark constituents, barkboard development, mechanical properties evaluation, characterization and improvement tests were performed. Various results support the possibility of bark utilization for barkboards production; however, more research is required for further improvements and feasible commercial production process.
2

Development of Bark-based Environmental-friendly Composite Panels

Gupta, Gireesh Kumar 19 January 2010 (has links)
Due to increasing shortage of wood supply and higher environmental concerns with the depletion of forest resources, in recent years, there is a strong interest in using forest and agricultural residues for development of value added products. Bark is a mill-waste residue, available in plenty, having limited uses and causing disposal problems. Bark possesses a large amount of phenolic compounds, which can act as an adhesive in making panels, however only limited research has been done in this area. The main objective of this project is to develop bark-based environment-friendly panels with and without synthetic resins, using mountain pine beetle infested lodgepole pine barks. Analysis of bark constituents, barkboard development, mechanical properties evaluation, characterization and improvement tests were performed. Various results support the possibility of bark utilization for barkboards production; however, more research is required for further improvements and feasible commercial production process.
3

Using mobile distributed pyrolysis facilities to deliver a forest residue resource for bio-fuel production

Brown, Duncan 10 December 2013 (has links)
Distributed mobile conversion facilities using either fast pyrolysis or torrefaction processes can be used to convert forest residues to more energy dense substances (bio-oil, bio-slurry or torrefied wood) that can be transported as feedstock for bio-fuel facilities. All feedstock are suited for gasification, which produces syngas that can be used to synthesise petrol or diesel via Fischer-Tropsch reactions, or produce hydrogen via water gas shift reactions. Alternatively, the bio-oil product of fast pyrolysis may be upgraded to produce petrol and diesel, or can undergo steam reformation to produce hydrogen. Implementing a network of mobile facilities reduces the energy content of forest residues delivered to a bio-fuel facility as mobile facilities use a fraction of the biomass energy content to meet thermal or electrical demands. The total energy delivered by bio-oil, bio-slurry and torrefied wood is 45%, 65% and 87% of the initial forest residue energy content, respectively. However, implementing mobile facilities is economically feasible when large transport distances are required. For an annual harvest of 1.717 million m3 (equivalent to 2000 ODTPD), transport costs are reduced to less than 40% of the total levelised delivered feedstock cost when mobile facilities are implemented; transport costs account for up to 80% of feedstock costs for conventional woodchip delivery. Torrefaction provides the lowest cost pathway of delivering a forest residue resource when using mobile facilities. Cost savings occur against woodchip delivery for annual forest residue harvests above 2.25 million m3 or when transport distances greater than 250 km are required. Important parameters that influence levelised delivered costs of feedstock are transport distances (forest residue spatial density), haul cost factors, thermal and electrical demands of mobile facilities, and initial moisture content of forest residues. Relocating mobile facilities can be optimised for lowest cost delivery as transport distances of raw biomass are reduced. The overall cost of bio-fuel production is determined by the feedstock delivery pathway and also the bio-fuel production process employed. Results show that the minimum cost of petrol and diesel production is 0.86 $ litre-1 when a bio-oil feedstock is upgraded. This corresponds to a 2750 TPD upgrading facility requiring an annual harvest of 4.30 million m3. The minimum cost of hydrogen production is 2.92 $ kg-1, via the gasification of a woodchip feedstock and subsequent water gas shift reactions. This corresponds to a 1100 ODTPD facility and requires an annual harvest of 947,000 m3. The levelised cost of bio-fuel strongly depends on the size of annual harvest required for bio-fuel facilities. There are optimal harvest volumes (bio-fuel facility sizes) for each bio-fuel production route, which yield minimum bio-fuel production costs. These occur as the benefits of economies of scale for larger bio-fuel facilities compete against increasing transport costs for larger harvests. Optimal harvest volumes are larger for bio-fuel production routes that use feedstock sourced from mobile facilities, as mobile facilities reduce total transport requirements. / Graduate / 0791 / drbrown@uvic.ca
4

Grotuttaget igår, idag och dess potentiella framtid : Med utgångspunkt från Energimyndighetens syntesrapport från 2012

Skär, Martin January 2019 (has links)
År 2012 publicerades en sammanfattande syntesrapport från Energimyndigheten (2012). Rapporten fann bevis på att grotuttaget låg på ca 14 TWh/år. Rapporten visar också att Sveriges skogar kan hantera upp till 24 TWh/ år utan att orsaka allvarliga konsekvenser på omgivningen eller nästkommande generationer av träd. Studien beräknade grotens potentiella uttag utifrån insamlade analyser av markkemi, tekniska verktyg och uppskattningar. Dagens rapporter angående ämnet estimerar potentialen till ungefär densamma med en liten höjning till ca 27-30 TWh/år. Detta har satts i relation till hur olika hyggeslagrings tekniker påverkar det möjliga uttaget av grot tillsammans med hur kemin i marken påverkar trädens tillväxt och omgivningen. Grotuttaget gick ner till ca 8-9 TWh/år från år 2012 till 2019, från 14 TWh/år. Eftersom skogsägarna i Sydsverige är privatbrukare och behöver gå runt ekonomiskt för att kunna fortsätta sina verksamheter leder detta till att grotuttaget följer kostnadseffektiviteten av grot i sverige. I framtiden uppskattas det att grotuttaget kan öka drastiskt. Beroende på hur utvecklingen sker kan det verkliga uttaget skilja stort med många påverkande faktorer som t.ex. kostnadseffektivitet och utveckling av andra energikällor. / In 2012 a synthesis report was published by ”Energimyndigheten (2012)”. The report states that forest residues used as bioenergy represents around 14 TWh/year. The report also shows that Swedish forests can manage an outtake of up to 24 TWh/year without suffering from serious consequences, -on the plantation grounds or for, the next coming generation of trees. The study calculated the potential residue of forest outtake from collected analysis of soil chemistry, technical tools and estimations. Recent reports on forest residue outlet estimates a potential of about the same as 2012 with a slight rise to approximately 27-30 TWh/year. This has been put into relation of how different logging storage techniques affect the trees growth, the plantation grounds and the surroundings. The forest residue outlet went down to between 8-9 TWh/year from 2012-2019. This is because the main part of the forests in southern Sweden belongs to private owners and who experienced a decreasing economy to sell their residue. That leads to a problem, where the actual forest residue outlet is heavily dependent on the cost efficiency of forest residues. In the future it is estimated that the forest residue outlet can increase drastically. Depending on how the development proceed, the future outlet of forest residues may differ greatly depending on the future cost efficiency and how other energy sources develop and progress.
5

Hur mycket står risskotare stilla på grund av kommunikationsproblem? / How much impact does communication problems have on inactivity for residue forwarders?

Andersson, Anton, Davidsson, Adrian January 2019 (has links)
The communicative interaction between contractor and subcontractor of residue forwarder plays a crucial role in the efficiency of handling forest residue. Since that type of work is at the end of the harvesting process, it may be that it is not as prioritized as the previous harvesting measures. The study investigates the communicative interaction between subcontractor that drives a residue forwarder and contractor and its connection to work-related production stops. The study was accomplished by a web-based survey and quantitative interviews conducted with eight selectively selected residue forwarder drivers in southern Sweden. The result of the survey showed that the average of all total production stops was one hour and 52 minutes under an average stop period of 25 working days. Most of the stops were caused by other work-related problems. Communication problems accounted for 20% of the number of production stops and the average stop duration was one hour and five minutes. The time when a residue forwarder was inactive seventeen minutes per day. In conclusion, the communicative problems are not the main reason to inactivity for residue forwarders. However, communication plays an important role in productive harvesting and represent the biggest possibility for improvement in the communication between residue forwarder drivers and contractor, which could lead to fewer production stops.     Residue Forwarders, Communication Problems, Production Stop and Forest residue. / Det kommunikativa samspelet mellan uppdragsgivare och risskotarförare kan vara ett led i effektiviteten vid hanteringen av GROT, vilket är en förkortning för grenar och toppar. I och med att arbetet infaller sist i avverkningsledet kan det vara lägre prioriterat än de tidigare avverkningsåtgärderna. Studien undersöker det kommunikativa samspelet mellan risskotarförare och uppdragsgivare och dess anknytning till arbetsrelaterade produktionsstopp. Det gjordes med hjälp av en webbaserad enkät ochkvantitativa intervjuer som genomfördes av åtta selektivt utvalda risskotarförare i södra Sverige. Resultatet från den webbaserade enkätundersökningen visar att medelvärdet av alla sammanlagda produktionsstopp var en timme och 52 minuter under en medelvärdesperiod av 25 arbetsdagar. Störst andel stopp orsakas av övriga problem. Kommunikationsproblem stod för 20 % av antalet produktionsstopp och medelvärdet av stoppens längd var en timme och fem minuter. Tiden då en risskotare står stilla under en arbetsdag uppgick till sjutton minuter. Sammanfattningsvis kan det klargöras att de kommunikativa problemen inte är den största orsaken till att risskotare står stilla. Dock spelar kommunikationen en viktig roll för ett produktivt avverkningsarbete. Slutligen finns det förbättringsmöjligheter i kommunikationen mellan risskotarförare och uppdragsgivare vilket skulle kunna leda till färre produktionsstopp.   Risskotare, Kommunikationsproblem, Produktionsstopp och GROT.
6

Will substituting fossil fuels with biofuels lead to a net reduction in CO2 emissions? : The case of district heating in Norrköping municipality / Ger ersättningen av fossila bränslen med biobränslen en nettosänkning i utsläpp av CO2? : Fjärrvärmefallet i Norrköpings kommun

Ljungberg, Stina January 2018 (has links)
With global warming and the international, national and local goals of reducing greenhouse gas net emissions, the phasing out of fossil fuels are of great importance. One energy source resulting in nearly no net emissions are biofuels. Residue from the forest industry, such as tops and branches, is already today in Sweden an important source of energy, especially in the district heating sector. The demand for forest residue is estimated to increase until 2050 and the potential harvest is a lot larger than what is utilized today. This master thesis tests the hypothesis of biofuels having a climate positive effect when replacing fossil fuels, despite the loss of carbon in the forest soil, which is a feedback of harvesting forest residue. The municipality of Norrköping here works as a case as they are standing in the forefront of turning towards a bio-based economy and a fossil free energy system. The biogeochemical model ForSAFE was used to study if Norrköping can replace all their fossil fuels and solid waste in the district heating for the municipality’s households and public facilities with forest residue from the forest within the municipality’s administrative boundaries. The result show that the productive forest area of the municipality does not yield enough forest residue to fulfil the energy demand from the fossil fuels and the waste. Meanwhile, the soil organic carbon was shown to be decreasing over the simulated years (2000-2300), although the loss did not exceed the emissions from the burning of the replaced fossil fuels. If the productive forest had been large enough to yield enough biomass to meet the demand, the loss of soil organic carbon would still not exceed the amount of carbon dioxide that the fossil fuels would have emitted. This indicates a positive climate effect when replacing fossil fuels with forest residue, reducing net emissions to the atmosphere. Despite the low yield of biomass compared to the energy demand from fossil fuels and waste in Norrköping, a study like this gives a projection of the biomass production and the feedbacks. These effects will be affected by different forest management scenarios and the change in climate. The silvicultural practices have however shown to have negative impacts on the Swedish Environmental Quality Objectives. Threatening the biodiversity and leaching of nutrients and chemicals, resulting in additional feedbacks downstream are examples of effects from disturbance in the forest and forest soil. It is therefore of great importance to consider the natural environment and neatly plan around forestry operations. In the end, the climatic benefit of switching to a fossil free energy system with the help of forest biofuels will have to weighted against the negative impacts. With a landscape view used and great knowledge about feedback effects when forestry planning, the input of biofuels can be a natural way to go for several municipalities in Sweden when wanting to create a bio-based economy with zero net emissions of greenhouse gases. / Med global uppvärmning och de internationella, nationella och lokala målen om reducerade växthusgasutsläpp, är utfasningen av fossila bränslen av stor betydelse. En energikälla som ger nära noll nettoutsläpp är biobränslen. Rester från skogsindustrin, som toppar och grenar (grot) är redan idag i Sverige en viktig energikälla, speciellt inom fjärrvärmesystemet. Efterfrågan på grot väntas öka fram till år 2050 och skördepotentialen är mycket större än vad som idag utnyttjas. Detta examensarbete testar hypotesen om att biobränsle är klimatpositivt när det ersätter fossila bränslen, trots kolförlusten i marken som uppstår när grot skördas. Norrköpings kommun används här som fall då de står i framkant när det gäller övergången till en biobaserad ekonomi och ett fossilfritt energisystem. Den biogeokemiska modellen ForSAFE användes för att studera om Norrköping kan byta ut alla sina fossila bränslen samt avfall, som förser kommunens invånare och offentliga lokaler medvärme och varmvatten via fjärrvärmenätet, mot grot från skogsmarkerna inom kommunens gränser. Resultatet visar att den produktiva skogsmarken i kommunen är för liten för att producera tillräckligt med grot för att ersätta allt fossilt bränsle och allt avfall. Samtidigt sjönk markkolet över de simulerade åren (2000-2300) även om förlusten inte översteg utsläppen från förbränningen av de ersatta fossila bränslena. Om den produktiva skogen hade varit stor nog att kunna ersätta de fossila bränslena såhade förlusten av markkol ändå inte varit större än utsläppen från de fossila bränslen som kunnat ersättas. Detta indikerar den klimatnytta som bytet från fossila till biobaserade bränslen ger när nettoemissioner reduceras från atmosfären. Trots den låga skördenivån av grot i förhållande till den energi som de fossila bränslena och avfallet tillför i Norrköping, kan en studie likt denna ge en uppfattning om hur mycket grot som kommer kunna produceras i framtiden och vilka effekter dessakan ha. Dessa effekter beror då på olika skördeintensitet och ett förändrat klimat. Skogsbruket har dock visat sig bidra till att försvåra att de svenska miljömålen nås. Hot mot biodiversiteten samt läckage av näringsämnen och tungmetaller som ger problem nedströms är exempel på effekter av störningar i skogen och skogsmarken. Detta gör att visad hänsyn till den naturliga miljön och god planering kring ingrepp i skogen är av stor vikt. De positiva klimateffekterna av att utnyttja biobränslen från skogen för att ersätta fossila bränslen kan därför komma att behöva ställas mot de negativa ekologiska konsekvenserna av skogsbruket. Med ett landskapsperspektiv och stor kunskap kring effekterna av skogsbruket kan biobränslet komma att bli en naturlig väg att gå för flera kommuner i Sverige som vill övergå till en biobaserad ekonomi med noll utsläpp av växthusgaser.
7

Restauração de áreas degradadas por exploração mineral no Planalto Catarinense / Restoration of degraded areas by mineral exploration at Planalto Catarinense

Martins, Daiany Augusta Paes 09 March 2017 (has links)
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-14T14:29:41Z No. of bitstreams: 1 PGEF17MA081.pdf: 3522802 bytes, checksum: 3cd9d4172b3367e2c998114fe05428a1 (MD5) / Made available in DSpace on 2017-12-14T14:29:41Z (GMT). No. of bitstreams: 1 PGEF17MA081.pdf: 3522802 bytes, checksum: 3cd9d4172b3367e2c998114fe05428a1 (MD5) Previous issue date: 2017-03-09 / FAPESC / This work had as objective evaluate the potential techniques of nucleation and forest residue in the restoration of degraded areas by gravel extraction process.To that end, 68 plots were installed in total, 40 of them in the area called Westarp, where the soil is Alumínico Humic Cambisols and the 28 others in Lauro area, where the soil was built with forest residue. Both areas were composed by different nucleation techniques: artificial perches, brushwood windrowing, litterfall and soil’s seed bank transposition, and planting of native trees in groups. The plots size were 1 m x 1 m, except for the planting in groups. All individuals regenerating above 10 cm high in the plots were accounted for, identified and classified in terms of the way of life, guild regeneration and dispersal syndrome. Were determined the following chemical properties (pH in water, MO, K, Ca, Mg, Al, P, Cu, Zn, Mn and total tenor of soluble salts) and the following Physical properties (total porosity, density, easily available water and soil resistance in penetration) of the soil. Regenerative component data were analyzed through Shannon-Wiener index of diversity (H'), equability of Pielou (J), Morisita index of dispersion and non-metric multidimensional scaling (NMDS). The presence of fauna was determined by evidence in different techniques. It was conducted a grouping analyses to collect the data of the planting in groups using Ward binding method and later discriminant analysis, also was calculated the survival rate. Were found 3328 regenerating individuals belonging to 85 species, summarised in 19 families and 53 genres. The greatest wealth families were Poaceae, Asteraceae, Cyperaceae and Fabaceae. In relation to the way of life: Herbaceous (80%); shrubby (18%) and tree (2%). As for the Guild regeneration: Pioneer (79%); Initial secondary (20%) and Late secondary (1%). Regarding dispersal syndrome: 53% Anemochoric; 35% Autochorous and 12% Zoochoric. The greater richness and diversity were observed in Lauro area and NMDS has shown that the regenerative component presented distinction in floristic and structural, mainly due to soil conditions. The litterfall and soil’s seed bank transposition and brushwood windrowing the most efficient techniques for the restoration of degraded areas. The grouping analysis technique and discriminant analysis enabled the formation of three distinct groups composed by species with similar growth. The species that showed potential for restoration under the conditions studied were Mimosa scabrella, Schinus terebinthifolius, Gymnanthes klotzschiana, Inga marginata and Allophylus edulis for Westarp and Schinus terebinthifolius, Schinus molle, Annona sylvatica, Vitex megapotamica and Gymnanthes klotzschiana for Lauro. The estimated cost with the implantation of nucleation techniques of restoration was of R$ 17.469,00/ha. It is concluded that the nucleation techniques deployed and the residue used as soil showed the potential to be used in the restoration of degraded areas, but temporal character studies of the biological attributes of soil and environmental characterization of the area must be done for inferences more conclusive about track of the areas / Este trabalho teve como objetivo avaliar a potencialidade de técnicas de nucleação e do resíduo florestal na restauração de áreas degradadas pelo processo de extração de cascalho. Para tal, foram instaladas 68 parcelas, sendo 40 na área denominada Westarp, cujo solo é Cambissolo Húmico Alumínico e 28 parcelas na área Lauro, cujo solo foi construído com resíduo florestal. Ambas as áreas foram compostas por diferentes técnicas nucleadoras: poleiro artificial, enleiramento de galharia, transposição de serapilheira e do banco de sementes do solo e plantio em núcleo de Anderson. A dimensão das parcelas foi de 1 m x 1 m, exceto para o núcleo de Anderson. Todos os indivíduos regenerantes acima de 10 cm de altura presentes nas parcelas foram contabilizados, identificados e classificados quanto à forma de vida, guilda de regeneração e síndrome de dispersão. Foram determinadas as seguintes propriedades químicas (pH em água, teores de MO, K, Ca, Mg, Al, P, Cu, Zn, Mn e teor total de sais solúveis) e físicas (porosidade, densidade, água facilmente disponível e resistência do solo à penetração) do solo. Os dados do componente regenerativo foram analisados por meio do índice de diversidade de Shannon-Wiener (H’), equabilidade de Pielou (J), índice de dispersão de Morisita e escalonamento multidimensional não métrico (NMDS). A presença da fauna foi averiguada por meio de vestígios nas diferentes técnicas. Para os dados do plantio em núcleo de Anderson foi realizada a análise de agrupamento pelo método de ligação Ward e posterior análise discriminante, além de calculada a taxa de sobrevivência. Foram encontrados 3328 indivíduos regenerantes pertencentes a 85 espécies, reunidas em 19 famílias e 53 gêneros. As famílias de maior riqueza foram Poaceae, Asteraceae, Cyperaceae e Fabaceae. Em relação à forma de vida: Herbácea (80%), Arbustiva (18%) e Arbórea (2%). Quanto à guilda de regeneração: Pioneira (79%); Secundária Inicial (20%) e Secundária Tardia (1%). Quanto à síndrome de dispersão: 53% Anemocórica; 35% Autocórica e 12% Zoocórica. A maior riqueza e diversidade foram observadas para a área Lauro e a NMDS mostrou que o componente regenerativo apresentou diferenciação florístico e estrutural, sobretudo em função das condições edáficas. A transposição de serapilheira e do banco de sementes do solo e o enleiramento de galharias foram às técnicas mais eficientes para a restauração das áreas degradadas. A técnica de análise de agrupamento e análise discriminante possibilitou a formação de três grupos distintos compostos por espécies com crescimento semelhantes. As espécies que apresentaram potencial para restauração nas condições estudadas foram Mimosa scabrella, Schinus terebinthifolius, Gymnanthes klotzschiana, Inga marginata e Allophylus edulis para Westarp e Schinus terebinthifolius, Schinus molle, Annona sylvatica, Vitex megapotamica e Gymnanthes klotzschiana para Lauro. Os custos estimados com a implantação das técnicas nucleadoras de restauração foi de R$ 17.469,00/ha. Conclui-se que as técnicas nucleadoras implantadas e o resíduo utilizado como solo apresentaram potencial para serem utilizados na restauração de áreas degradadas, porém estudos de caráter temporal dos atributos biológicos do solo e de caracterização ambiental da área devem realizados para inferências mais conclusivas sobre a trajetória das áreas
8

Hydrogen production from biomass

Sarkar, Susanjib Unknown Date
No description available.
9

Hydrogen production from biomass

Sarkar, Susanjib 11 1900 (has links)
Hydrogen can be produced from biomass; this hydrogen is called biohydrogen. Biohydrogen produced in Western Canada can partially contribute to meeting the demand for hydrogen needed for bitumen upgrading. Gasification and pyrolysis are two promising pathways for producing biohydrogen in a large-scale plant. Syngas, produced from the gasification of biomass, and bio-oil, produced from fast pyrolysis of biomass, can be steam reformed to produce biohydrogen. The cost of biohydrogen delivered by pipeline to a distance of 500 km is $2.20 per kg of H2, assuming that a plant utilizes 2000 dry tonnes of whole-tree biomass per day processing it in a Battelle Columbus Laboratory (BCL) gasifier. For forest residue- and straw-based biohydrogen plants the values are similar: $2.19 and $2.31 per kg of H2, respectively. Maximum economy of scale benefits are realized for biohydrogen production plants capable of processing 2000 and 3000 dry tonnes per day using BCL and GTI (Gas Technology Institute) gasification technology, respectively. The cost of biohydrogen from fast pyrolysis ($2.47 per kg of H2 from a 2000 dry tonne per day plant), using forest residue as the feedstock, is higher than the cost of biohydrogen produced by gasification. Carbon credits of about $120-$140 per tonne of CO2 are required to make biohydrogen competitive with natural-gas-based hydrogen.
10

Biodegradação de tocos de Eucalyptus sp. pela ação de cupins xilófagos / Biodegradation of stumps Eucalyptus sp. by the action of termites xylophogous

Chagas, Thiago Xavier 24 February 2016 (has links)
Eucalyptus plantations can be managed under the cutting regime and retirement or coppice. After harvest there is the remnants’ accumulation of hard degradation culture, including the stump. This forest residue can be a micro-habitat and abundant food source for termites. The identification of termites’ species that occur at stumps can be a viable alternative to accelerate the process of degradation, assisting in partial or total removal. The aim of the study was to identify species of termites in stumps of Eucalyptus urograndis and evaluate its biodegradation in areas with two and four years old after cutting. The study was conducted in two areas, with aftercut ages of two and four years, located in the city of Entre Rios, Bahia, Brazil. The stumps were fragmented, with the aid of a cutter, and termites collected and deposited in 15 ml Falcon tubes, containing 80% alcohol. The termites were identified by key taxonomic aid and comparisons among copies from the base collection of Forest Entomology Laboratory of the Federal University of Sergipe, and the Zoology Museum of the University of Sao Paulo. The measurement of the diameter and height of the stumps were performed before and after fragmentation. After this measurement, the initial volume and the final volume of the stumps were calculated, to determine their biodegradation. To evaluate stumps’ biodegradation in the aftercut ages, data were analyzed by SAS 9.0 software, using the ANOVA for comparison. Seven species of termites, which belongs to four genera in the Termitidae family, were collected. Nasutitermes corniger, N. kemneri and Amitermes amifer were dominants. In the stumps biodegradation analysis was verified a significant difference between the afetrcut ages of two and four years. It is possible to find termites in stumps of Eucalyptus urograndis foraging alone or associated with other species. They are able to biodegrade stumps of Eucalyptus urograndis areas aged two and four years after cutting. There is an increasing trend in biodegradation of the stumps in area with higher post-crop age, as observed in the area with four years of age. / As plantações de eucalipto podem ser manejadas sob o sistema de alto fuste ou em talhadia, sendo que após a colheita há o acúmulo de restos da cultura de difícil degradação, incluindo o toco. Este resíduo florestal pode representar um micro-habitat e recurso alimentar abundante para cupins. A identificação das espécies de cupins que ocorrem em tocos pode ser uma alternativa viável para acelerar o seu processo de degradação, auxiliando na remoção parcial ou total dos tocos. O objetivo do estudo foi identificar espécies de cupins em tocos de Eucalyptus urograndis e avaliar a sua biodegradação em áreas com dois e quatro anos de idade após o corte do primeiro ciclo de plantação. O estudo foi conduzido em duas áreas, com idades de dois e quatro anos após o corte, localizadas no município de Entre Rios, Bahia, Brasil. Os tocos foram fragmentados, com auxílio de um facão, e os cupins coletados e depositados em tubos Falcon 15 ml, contendo álcool 80%. Os cupins foram identificados com auxílio de chave taxonômica e comparação com exemplares da coleção base do Laboratório de Entomologia Florestal, da Universidade Federal de Sergipe, e do Museu de Zoologia, da Universidade de São Paulo. A medição do diâmetro e altura dos tocos foi realizada, antes e após a sua fragmentação. Após esta medição, foi calculado o volume inicial e o volume final dos tocos. Para avaliar a biodegradação de tocos, os dados foram convertidos para porcentagem e analisados pelo programa SAS 9.0, usando para comparação a ANAVA. Foram coletadas sete espécies de cupins, pertencentes a quatro gêneros, da família Termitidae. Nasutitermes corniger, N. kemneri, e Amitermes amifer foram dominantes. Na análise de biodegradação dos tocos houve diferença significativa entre as idades de dois e quatro anos, sendo a biodegradação maior na área com quatro anos de idade após o corte. É possível encontrar espécies de cupins em tocos de Eucalyptus urograndis, sejam forrageando isoladamente ou associações com outras espécies, sendo elas capazes de biodegradar tocos de Eucalyptus urograndis nas áreas com idade de dois e quatro anos após o corte. Há uma tendência de aumento na biodegradação dos tocos em área com maior idade após o corte, como constatado na área com quatro anos de idade.

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