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Training and Pruning Newly Planted Decidous Fruit TreesDeGomez, Tom 06 1900 (has links)
6 pp. / Training and pruning newly-planted deciduous fruit trees is one of the most important steps in developing trees with a strong framework (scaffold branches). Trees with a good framework of branches can support heavy crops without limb breakage and will help to bring the young tree into production at an early age. Selection and arrangement of these branches determines the type of development and growth in later years. The goal of pruning and training is to balance vegetative and fruiting wood growth.
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Reproducing Canada's colonial legacy: a critical analysis of Aboriginal issues in Ontario high school curriculumWatters, Jordan Austin 29 August 2007 (has links)
Canadian education has historical roots in blatantly assimilationist policies bent on the social, economic, linguistic and spiritual subjugation of Aboriginal peoples and their cultures. Today, Canadian education has moved away from overtly colonialist discourses and publicly embraced the principles of multiculturalism. This research explores how and if this ideological shift has translated into the practice of contemporary Canadian education as it is experienced by students. My research focuses on the ways Canada’s colonial history and contemporary Aboriginal issues are addressed in mandatory Ontario high school social studies curriculum. This analysis is based on interviews with twenty-five recent high school graduates about what they remember learning about Aboriginal issues and how that knowledge has influenced their understanding of colonialism and Aboriginal peoples today. My interpretive analysis of students’ responses relies on the insights provided by critical pedagogy and postcolonial theory. By drawing on Gramsci, Freire and Apple I challenge the hegemonic practices in education that continue to marginalize Aboriginal peoples and their struggles. This research contributes to scholarship in the sociology of education and postcolonial studies by providing a unique picture of the ways in which young people come to understand Canada’s colonial legacy through their formal education, as well as providing insight into new directions for curriculum development, teacher training and more effective integration of anti-racist pedagogy in Ontario’s high schools. / Thesis (Master, Sociology) -- Queen's University, 2007-08-23 17:38:27.532
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Risky Discourse: pesticide use and recent developments in the greening of New Zealand's pipfruit industryJowsey, Tanisha January 2005 (has links)
The New Zealand pipfruit industry has changed dramatically over the past fifteen years due to major industry restructuring and deregulation, and also due to the adoption of more environmentally sustainable growing strategies. This thesis traces the socio-political context of pesticide use in the pipfruit industry over the past ten years (couched within a hundred year trajectory), through a content and discourse analysis of appropriate print and electronic material. The content analysis addresses the ways in which pesticide use has been framed in New Zealand's fruit journal entitled The Orchardist, and tracks its promotion of the ENZA Integrated Fruit Production program that was introduced to New Zealand pipfruit growers during the summer of 1997/98. The Foucauldian discourse analysis explores how print media reflects and produces knowledge, and how such knowledge causes transformation within the pipfruit industry. Identified in the print media are several central ideologies and themes that frequently serve as conceptual frameworks for interpreting issues that arise in the pipfruit industry, the most prominent of which, is risk. Therefore, risk is the key discourse explored in this thesis. The combined content and discourse analysis signal ways in which power operates through discourse to influence ideologies, world-making and modes of production.
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Stoffliche Nutzung industrieller Abprodukte in Biogasanlagen am Beispiel Apfeltrester / Utilization of industrial waste products like apple pomace in biogas production plantsBedrich, Karl 03 May 2011 (has links) (PDF)
Die folgende Arbeit beschreibt Potentiale und Risiken der Nutzung industrieller Abprodukte am Beispiel des Apfeltrester – einem Pressrückstand der Apfelsaftgewinnung. Dieser spielt aus finanzieller und ökologischer Sicht als Abprodukt eine steigende Rolle bei der Biogassynthese. Dabei werden die Ergebnisse des vorangegangenen Fachpraktikums vorgestellt und diskutiert.
Darauf aufbauend wurden Thesen erstellt und anhand ermittelter Messwerte sowie der Literatur verifiziert. Schlussendlich werden in einer Wirtschaftlichkeitsrechnung Kosten von Bezug, Lagerung und Beschickung den Gewinnen aus der Einspeisevergütung gegenüber gestellt.
Es konnte gezeigt werden, dass Apfeltrester unter Laborbedingungen nicht die befürchtete Übersäuerung des anaeroben Abbauprozesses zur Folge hatte, sondern unter vergleichbaren Erträgen mit leicht höherer Sicherheit zur Maissilage bis zu einem gewissen Anteil zu Maissilage und Stallgülle zugesetzt werden kann. / Due to the increasing ecological and financial importance of industrial waste products in the recovery of biogas the following thesis describes potentials and risks of the usage of one of these products using apple pomace – the filter cake of the apple juice production.
Thereby the issues of the three-month practical course in the LHL Eichhof, a laboratory in middle Germany, are shown and discussed. As conclusion several theses are given and verified with help of the taken measurements and scientific literature. At the end an economical calculation compares the present costs of purchase, storage and processing with the proceeds of the reimbursement by the german renewable energy sources act (EEG).
Against the misgiving that apple pomace could decrease the pH-value to an unacceptable level for the anaerobic decomposition process the fermentation of this product gets a comparable output even with a little more reliability compared to corn silage when added up to a defined level to corn silage and slurry.
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Bekämpfung des ApfelmehltausKröling, Christian 28 June 2014 (has links) (PDF)
Der Bericht informiert über die Ergebnisse des Projektes »Bekämpfung des Echten Mehltaus am Apfel mit dem Wirkstoff Penconazol im Raum Sachsen«. Die Untersuchung erfolgte im Zeitraum von 2010 bis 2012 in Labor- und Feldversuchen.
Für eine optimale Bekämpfung des Erregers Podosphaera leucotricha ist die Erziehung des Baumes zu einer schlanken Krone unumgänglich. Der Primärbefallsdruck in einer Anlage und der angrenzenden Flächen darf 5 % nicht überschreiten. Untersuchungen der Wirkstoffverteilung mit wassersensitivem Papier und Rückstandsanalysen in Blättern sind für die Beurteilung der Feldleistung von Penconazol notwendig. Diese ermöglichen den Bezug zu im Biotest erhobenen Sensitivitätswerten. Ein »shifting« der Schaderregerpopulation in der Peconazolsensitivität ist zu erkennen, jedoch keine Resistenz.
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電子書興起對出版業的影響之產業分析與投資應用 / The shock of the emergence of e-books upon publishers, relevent industry analyses, and investment implications謝菱純, Sie, Ling Chun Unknown Date (has links)
電子書興起,改變了讀者的閱讀方式,紙本書不再是唯一的選擇。電子書的供應鏈由上而下可分為:作者、出版社、DRM業者、網路通路平台、電信業者、硬體載具製造商。隨著科技創新,新的供應鏈創造了參與者新的競合模式,各參與者的商業模式也隨之創新,相較於過去的紙本書市場出版商擁有較大的議價能力之情況,在新的競合模式中,掌握客源的網路平台通路商對於上游的出版商之議價能力大幅提升。另一方面,越來越多作者跳過出版社,直接將電子書的版權賣給網路平台通路商,導致出版商原有的掌握版權之優勢減弱,長期下可能會致使出版社在電子書供應鏈中的議價能力進一步降低。未來隨著科技進步,彩色電子書閱器與結合其他功能的設備將是發展趨勢,但光靠硬體端難以建立他人無法輕易突破的進入障礙,而許多參與者在供應鏈上並非具單一角色,像是Amazon與Apple兼具網路平台通路商與硬體載具供應商之角色,亦即「平台+硬體載具」的雙重獲利模式,而這兩間公司皆掌握了主要的「客源」,是其重要優勢。而Amazon更是透過支援的應用程式,讓非自家載具之消費者也能至自己的電子書店下載電子書,像是iPad、iPhone、藍莓機等等。因此以未來電子書成長後議價能力與賺取現金流之能力的消長預期來看,相較於其他參與者,Amazon與Apple會是較佳的長期投資標的。 / The emergence of e-books changes the reading habit, and the paper-book is not the only one medium of reading anymore. The supply chain of e-books comprises diversified industries, including authors, publishers, DRM providers, online retailers who operate digital bookstores and manage accounts of customers, telecommunications, technology-side players. When technology advances, the new supply chain creates new co-competition model, the business models of players begins to innovate. Compared to paper-book market in which the publishers have stronger bargaining power, in new co-competition models, the online retailers have a huge customer base and therefore have stronger bargaining power over publishers. Furthermore, there are more and more authors who skip publishers and sell the digital right to online retailers directly. That is, the content resources controlled by publishers reduce, and the bargaining power of publishers deteriorates.
In the future, producing colorful e-readers will not be a difficulty anymore, but the technology-side players will have difficulty in establishing entrance barrier. However, some participants play various roles across the supply chain, such as Amazon and Apple. Both of two companies play the roles of online retailers and technology-side players, and have double sales resources from plate form and hardware. Beside, both of these companies have large customer base, and it is the critical competitive advantage of Amazon and Apple. Especially, Amazon supports some hardware tools like iPad, iPhone, and Blackberry. As long as the customers download the application programs, the customers can purchase e-books on Amazon.com. From the aspects of potential of growing bargaining power and future discounted cashflows, Amazon and Apple would be better choices for long-term investors.
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Determination of the methanogenic potential of an apple processing wastewater treatment systemPaulsen, Cindy 12 1900 (has links)
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2006. / The food and beverage industry generates large volumes of wastewater annually. The
disposal of factory effluent from the fruit processing industry has always been a cause of
concern to both the fruit processors and controlling bodies responsible for effluent
management. Traditional disposal of wastewater into sewerage works has become
undesirable due to its economical and environmental impacts. Therefore, on-site
anaerobic treatment of wastewater has received considerable interest due to lower capital
outlays and energy recovery possibilities. Thus, the aim of this study was to establish an
operational treatment profile for an anaerobic pond system treating fruit-processing
wastewater. The specific activity of the microbial populations was also monitored to
determine the effect of the fruit processing seasons (peak and off-peak season). The
biogas production potential at various temperatures was also assessed to determine the
viability of methane recovery.
The influence of the processing and environmental conditions on the ponds’
performance was established by monitoring various process parameters. The results
showed that the chemical oxygen demand (COD) levels decreased during the off-peak
season but the pond pH remained relatively stable between 6.0 and 6.4 during the entire
year. Pond alkalinity was found to be dependent on the regular lime dosing to maintain
the necessary alkalinity. The volatile fatty acid (VFA) concentrations indicated that the
microbial populations of the pond were functioning well. However, a decrease in microbial
activity and VFA concentrations were observed at the lower temperatures during the winter
months. The temperature profile of the pond showed that the pond temperature was
impacted by the fluctuations in the ambient air temperature. The general trend established
by the operational treatment profile clearly showed the impact of the peak and off-peak
season.
The sludge activity of the anaerobic pond was evaluated to determine the effect of
the apple-processing peak and off-peak season on the specific activity of the acidogenic
and methanogenic populations within the sludge. An activity test using four different test
media was used during the activity assays. Sludge samples were taken at four different
sampling positions across the pond’s sludge bed. The sludge was also subjected to a
biogas formation study, which was designed to simulate pond conditions on laboratory scale in order to evaluate the biogas production potential of the anaerobic pond. The
cumulative biogas volume and total CH4 composition showed little or no difference
between the four sludge sampling sites. A major difference was found between the activity
of the microbial populations during the peak and off-peak seasons. The overall trend
regarding the biogas production rate (SB) and the methane production rate (SM) values
showed an increased activity during peak-season and a decreased activity during off-peak
season. For the biogas formation test the highest incubation temperature (25°C) resulted
in the most biogas being produced, followed by 18°C, and with 10°C resulting in the lowest
biogas volume. The biogas formation tests indicated that microbial activity and therefore
biogas production was dependent on especially favourable temperature conditions. The
pond and activity of the microbial populations are therefore influenced by factors like
environmental changes such as decreased air temperatures and substrate changes such
as decreased COD concentrations during the off-peak season. This in turn influences the
rate of biogas production as well as the methane production rate.
The theoretical CH4 calculations and estimates based on the results obtained during
the biogas formation tests indicated that CH4 recovery from the anaerobic pond would
definitely be a worthwhile consideration. If it were assumed that the estimated CH4
volumes (based on only 15% of the pond volume for practical reasons) obtained could be
applied as an energy source, the minimum yearly savings in coal usage would amount to
about R 665 000.
This study was valuable in evaluating the factors such as pond conditions, pond
activity and air temperatures and the effect on the biogas production potential as well as
more importantly, CH4 production for the purpose of energy recovery.
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The combination of UASB and ozone technology in the treatment of a pectin containing wastewater from the apple juice processing industryVan Schalkwyk, Nico 12 1900 (has links)
Thesis (MSc Food Sc )--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The South African apple juice processing industry is growing rapidly and during the
harvesting season the wastewater volumes and organic loads increase significantly with a
considerable environmental impact. These larger apple juice processing wastewater
(AJPWW) volumes and chemical oxygen demand (COD) loads subsequently lead to faster
increases in the organic loading rate (OLR) of an upflow anaerobic sludge bed (UASB)
wastewater treatment system and it is necessary to know if the treatment system can
handle such drastic increases over short periods. The objective of the study were to
evaluate the efficiency of the UASB process in the treatment of an AJPWW; to determine
what effect a substrate viscosity increase, based on a pectin calcium gel has on the
performance of an UASB system, and to determine what impact ozonation has on the
pectin content, gelformation ability and biodegradability of the AJPWW.
The ability of the UASB to maintain stability during the apple-processing season
was investigated by increasing the OLR from 2.9 to over 14.0 kg COD.m-3.d-1 in 131 days.
During this time the COD removal remained constant at 85%, while the pH and alkalinity
remained at levels indicative of good reactor stability. It was thus concluded that the
UASB reactor could operate successfully during the apple-harvesting season when
wastewater volumes and organic loads increase significantly.
In the study it was found that the viscosity of the AJPWW, containing 750 mq.L-1
pectin, increased from 8.5 to 47.0 cps after a 312 rnq.L-1 Ca2
+ addition. This increased
viscosity substrate was then fed to an UASB reactor at an OLR of 15.0 kg COD.m-3.d-1.
During a 12 day increased viscosity (47 cps) feeding stage the COD removal decreased
from 94 to 11%, while the reactor pH decreased from 7.5 to 4.9. During this period, pectin
accumulated in the UASB and led to biomass washout and rapid UASB failure. The
possible elimination of pectin by ozonation was thus investigated, and a 77% decrease in
pectin content and 76% decrease in gel formation ability occurred after ozonation.
The effect of pre- and post-ozonation on the efficiency of the UASB system was
subsequently investigated. It was found that a 10 min pre-ozonation decreased the
AJPWW COD by 19% and the total suspended content by 36%, while the soluble portion
of the total COD was increased from 81.7 to 92.4%. This increase in soluble COD content
should lead to increased wastewater biodegradability. The ozonated AJPWW was then
used to replaced the raw non-ozonated AJPWW as reactor feed. Results showed that the
COD removal increased from 78 to 90% within 24 h of starting with the ozonated feed. It
was also found that the reactor stability improved after AJPWW pre-ozonation as an OLR
increase from 10.0 to 16.6 kg COD.m-3.d-1 in 23 days did not detrimentally influence the stability of the reactor. This reactor effluent (COD = 465 rnq.L-1) was then post-ozonated
which resulted in 64.8% COD and 79.0% colour reductions. The final effluent had a COD
of 180 rnq.L-1 (98% reduction).
The ability of the ozonation/digestion system as described in this study to degrade
AJPWW at a higher OLR is of value to the apple industry, as it may lead to larger organic
pollutant removals and thus a more effiecient treatment system. Increased reactor
performance will directly improve the quality of the final wastewater produced, which in
turn will have a significant impact on the treatment ability of the South African apple
processing industry currently limited by the production of large wastewater volumes. / AFRIKAANSE OPSOMMING: Gedurende die oesseisoen word groot volumes afvalwater met 'n hoe organiese lading in
die vinnig groeiende Suid-Afrikaanse appelsapprosesseringsbedryf geproduseer. Dit het 'n
groot impak op die omgewing. Die groter volumes appelsapprosesseringsafvalwater
(ASPAW) met 'n hoë organiese lading het 'n vinniger verhoging in organiese
ladingstempo's (OLT) van 'n UASB-waterbehandelingstelsel tot gevolg. Daarom is dit
belangrik om te weet of die stelsel die drastiese verhoging oor kort tydperke kan hanteer.
Die doel van hierdie studie was die evaluering van die effektiwiteit van die UASB-proses in
die behandeling van ASPAW; om te bepaal watter effek 'n substraatviskositeitsverhoging,
gebaseer op 'n pektien-kalsium-jel, op die doeltreffendheid van 'n UASB-stelsel het; en om
te bepaal watter impak osonering op die pektieninhoud, jelvormingsvermoe en
bioafbreekbaarheid van ASPAW het.
Die vermoe van die UASB om stabiliteit te handhaaf gedurende die
appelsapprosesseringseisoen is ondersoek deur die OLT van 2,9 tot bo
14,0 kg CSB.m-3.d-1 te verhoog oor 131 dae. Gedurende hierdie tyd het die chemiese
suurstofbehoefte- (CSB-) verwydering konstant gebly by 85%, terwyl die pH en alkaliniteit
ook op vlakke aanduidend van goeie reaktorstabiliteit gebly het. Daar is sodoende bewys
dat die UASB-reaktor suksesvol kan presteer tydens die appelsapprosesseringseisoen,
wanneer daar 'n beduidende verhoging in OLT plaasvind.
In die studie is daar gevind dat die viskositeit van die ASPAW, wat 750 mq.L-1
pektien bevat, van 8,5 tot 47,0 cps toeneem na die byvoeging van 312 rnq.L-1 Ca2+.
Hierdie verhoogde vikositeitsubstraat is tot die UASB-reaktor toegevoeg teen 'n OLT van
15,0 kg CSB.m-1.d-1. Gedurende 'n 12-dae toevoer van verhoogde viskositeit (47 cps), het
die CSB-verwydering van die reaktor afgeneem van 94% na 11%, terwyl die pH gedaal het
van 7,5 na 4,9. Gedurende hierdie tydperk het pektien in die UASB geakkumuleer, wat
gelei het tot die uitspoel van biomassa en vinnige UASB-reaktormislukking. Die moontlike
eliminasie van pektien, deur osonering, is daarom ondersoek. 'n Verlaging van 77% in
pektieninhoud en 76% in jelvormingsvermoe het na osonering plaasgevind.
Die effek van pre- en post-osonering op die effektiwiteit van 'n UASB-stelsel is
gevolglik ondersoek. Daar is gevind dat 'n 10 minute pre-osonering die CSB van die
ASPAW met 19% verlaag en die totale inhoud van gesuspendeerde vaste stowwe met
36% verlaag, terwyl die oplosbare gedeelte van die totale CSB van 81,7% tot 92,4%
gestyg het. Die verhoging in oplosbare CSB-inhoud behoort tot verhoogde
bioafbreekbaarheid van ASPAW te lei. Die geosoneerde ASPAW is gebruik om die rou,
ongeosoneerde ASPAW as reaktorsubstraat te vervang. Die resultate het getoon dat die CSB-verwydering verhoog het van 78% na 90% na 'n 24-uur toevoer van geosoneerde
substraat. Daar is ook gevind dat die reaktorstabiliteit toegeneem het na ASPAW
osoneering, aangesien 'n OLT-verhoging van 10,0 na 16,6 kg.CSB.m-3.d-1 in 23 dae nie die
stabiliteit van die reaktor nadelig beinvloed het nie. Hierdie reaktoruitvloeisel (CSB = 465
rnq.L-1) is hierna gepost-osoneer, wat 'n 64,8% CSB- en 79,0% kleurverlaging tot gevolg
gehad. Die finale uitvloeisel het 'n CBS-inhoud van 180 rnq.L-1 gehad (98,1%
verwydering).
Die vermoe van die osonering-/verteringstelsel om ASPAW te degradeer teen 'n hoër OLT,
soos beskryf in hierdie studie, is van waarde tot die appelsapprosesseringsbedryf,
aangesien dit tot groter organiese afvalstofverwydering kan lei en dus 'n meer effektiewe
behandelingstelsel tot gevolg kan hê. Verhoogde reaktordoeltreffendheid sal 'n direkte
verbetering tot gevolg hê in die gehalte van die finale afvalwater wat geproduseer word,
wat op sy beurt 'n beduidende impak sal hê op die behandelingsvermoe van die
appelsapprosesseringsbedryf, wat tans beperk word deur die produksie van groot volumes
afvalwater.
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An evaluation of the specific apple replant problem in Western Cape orchard soilsRabie, Louise 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Apple replant disease (ARD) is one of the major impediments to the establishment of
an economically viable apple orchard on sites previously planted to apple. In spite of
extensive research on ARD, the etiology remains to be fully elucidated. A possible
biological origin of ARD etiology in South Africa was investigated by the dilution of
replant field soil with sterilised soil. Commercial orchards with ARD were selected for
use in pot trials and disease severity evaluated after three months, by measuring
shoot length, dry mass of plants as well as root discolouration. Although diluting
replant soil to 25 and 50% (v/v) significantly reduced the effects of ARD, symptoms
were only absent in 0% replant soil. It was clear that seedlings planted in any
mixture containing replant soil, even only 25% replant soil, consistently exhibited
symptoms of stunted growth and root discolouration similar to those seedlings grown
in 100% replant soil. This indicates that ARD in South Africa is primarily of a
biological nature.
As an initial step in formulating sustainable disease control alternatives to replace
methyl bromide, pot trials were conducted to assess the impact of compost
treatments as well as biological control products on ARD. Compost as well as
sterilised and unsterilised compost teas (compost extract) significantly increased
seedling growth even under optimum nutrient conditions when compared to the
control, suggesting that they negate the effects of ARD. Results also indicated that
applying high concentrations of compost does not necessarily provide additional
growth benefits compared to lower concentrations. Results with biocontrol
formulations were less favourable. Only one of the biocontrol formulations, a
combination of Bacillus spp. (Biostart®) improved growth significantly compared to
the control. There was, however, some inconsistency with results for the different
trials conducted using this product.
Fungal as well as nematode populations associated with ARD soils were
characterised to the generic level to get a clearer understanding of the etiology of
ARD in South Africa. Pythium and Cylindrocarpon spp. were consistently isolated
from all six replant soils in all trials that formed part of this study, indicating that these
fungi may have a role in ARD etiology in South Africa. Nematodes implicated in ARD
development were inconsistently associated with ARD soils used in these studies.
This suggests that nematodes do not have a primary causal role in ARD etiology in
South Africa. Field trials were conducted in commercial orchards to assess the impact of organic
amendments and promising biological control products, as indicated by the pot trials,
on ARO severity under field conditions. These biological soil amendments were also
compared with the standard chemical control methods for ARO, methyl bromide and
chloropicrin. In all three trials established, compost and mulch as well as manure
and mulch, consistently increased growth to the same extent as the standard
chemical treatments and by combining these chemical treatments with organic
amendments a significant, additional growth increase could be attained. Biocontrol
formulations evaluated in field studies gave variable results. Biostart® improved
growth when applied on its own, but not in combination with the chemical Herbifume
(metham-sodium). Inoculating soil with effective microorganisms (EM), consisting
primarily of photosynthetic bacteria, had no significant effect on growth.
Results from this study indicate that application of organic amendments could
possibly substitute for soil fumigation in replanted apple orchards. However, compost
quality standards need to be implemented and because few types of compost are
universally effective, different types of composts should be compared in specific soil
environments before recommendations can be made. Oue to variable results with
biocontrol products, ARO management with these biological soil amendments cannot
be guaranteed at this stage and further studies are recommended. / AFRIKAANSE OPSOMMING: EVALUERING VAN DIE SPESIFIEKE APPELHERVESTIGING-PROBLEEM
IN BOORDE IN DIE WES-KAAP
Appelhervestiging-siekte (AHS) skep 'n groot probleem in die vestiging van jong
appelbome op grond waar daar reeds voorheen appels verbou is. Ten spyte van
omvangryke navorsing is die oorsaak van die probleem nog hoofsaaklik onbekend.
'n Moontlike biologiese oorsaakleer is in Suid-Afrika ondersoek deur die
hervestigings-effek te probeer verminder deur die vermenging van hervestigingsgrond
met gesteriliseerde grond. Kommersiële boorde met 'n appelhervestigingsprobleem
is geselekteer en gebruik in potproewe. Die ernstigheidsgraad van die
siekte is na drie maande se groei geevalueer deur lootlengte, droë massa en
wortelverkleuring te meet. Alhoewel verdunning van die hervestigingsgrond tot 50 en
25% (vlv) die effek van AHS op groei betekenisvol verminder het, kon die skadelike
effek van die veroorsakende faktor slegs uitgeskakel word deur saailinge in 100%
gesteriliseerde grond te plant. Dit was duidelik dat saailinge wat in enige
grondmengsel geplant is waarin hervestigingsgrond voorgekom het, selfs al was dit
net 25%, konsekwent simptome van vertraagde groei en wortelverkleuring getoon
het. Dit is 'n aanduiding dat AHS in Suid-Afrika hoofsaaklik biologies van aard is.
Potproewe is uitgevoer as 'n eerste stap in die formulering van volhoubare
siektebeheer-strategieë, om die impak van kompos-behandelings en biologiese
beheer produkte op AHS te ondersoek. Kompos sowel as gesteriliseerde en
ongesteriliseerde kompos-tee (kompos-water) het, selfs onder optimale voedingsomstandighede,
die groei van saailinge betekenisvol verbeter. Dit dui aan dat hierdie
behandelings die effek van AHS kan teenwerk. Resultate het ook daarop gedui dat
hoër kompos konsentrasies nie noodwendig enige addisionele voordele vir groei
inhou in vergelyking met laer konsentrasies nie. Resultate met biologiese beheer
produkte was minder gunstig. Slegs een van die produkte wat geëvalueer is, 'n
kombinasie van Bacillus spp. (Biostart®), het groei betekenisvol verbeter in
vergelyking met die kontrole. Resultate was egter inkonsekwent vir die verskillende
proewe waarin hierdie produk gebruik is.
Swampopulasies sowel as aalwurmpopulasies wat met hervestigingsgrond
geassosieer word, is geïdentifiseer tot op generiese vlak om vas te stel waardeur AHS in Suid-Afrika veroorsaak word. Pythium en Cylindrocarpon spp. is konsekwent
van al ses hervestigingsgronde geïsoleer wat daarop dui dat hierdie twee swamgenera
'n beduidende rol in AHS ontwikkeling in Suid-Afrika mag hê. Aalwurms wat
aangedui is in die literatuur om 'n moontlike rol in AHS te hê, was slegs in enkele
gevalle geassosieer met hervestigingsgronde waarvan in hierdie studie gebruik
gemaak is. Die gevolg-trekking is dus gemaak dat aalwurms nie 'n betekenisvolle rol
speel as hoof-veroorsakende organisme onder Suid-Afrikaanse toestande nie.
Veldproewe is uitgevoer in kommersiële appelboorde om vas te stel wat die effek van
organiese materiaal, asook belowende biologiese beheermiddels, soos aangedui
deur potproewe, op AHS onder veldtoestande is. Die biologiese grondtoedienings is
ook vergelyk met die standaard chemiese beheermiddels (metielbromied en
chloorpikrien). In al drie proewe wat gevestig is, het kompos met 'n deklaag, sowel
as kraalmis met 'n deklaag, groei betekenisvol verbeter tot dieselfde mate as
chemiese middels. Daar kon ook 'n beduidende, addisionele groeitoename gemeet
word in gevalle waar chemiese middels met organiese materiaal gekombineer is.
Resultate met biologiese beheer formulasies wat onder veldtoestande geëvalueer is,
het gevarieer. Biostart® het groei verbeter wanneer dit alleen toegedien is, maar in
kombinasie met die chemiese middel Herbifume (metham-sodium) het dit geen effek
gehad nie. Die inokulering van grond met 'n oplossing van effektiewe mikroorganismes
(EM) wat hoofsaaklik uit fotosinterende baterieë bestaan, het ook geen
betekenisvolle effek op groei gehad nie.
Die gevolgtrekking is gemaak dat toediening van organiese materiaal moonlik as
plaasvervanger vir metielbromied-beroking kan dien in die beheer van AHS. Die
nodige komposkwaliteit-standaarde moet egter eers geïmplimenteer word. Omdat
feitlik geen kompos universeel effektief kan wees nie, is dit ook nodig dat verskillende
tipes kompos met mekaar vergelyk moet word in spesifieke grondtoestande voordat
verdere aanbevelings gemaak kan word. As gevolg van variërende resultate met
biologiese beheer produkte kan AHS beheer met hierdie middels nie gewaarborg
word op hierdie stadium nie en verdere studies word aanbeveel.
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Produção de pellets para energia usando diferentes resíduos de biomassa agrícolas e florestais / Production of pellets for energy using different agricultural and forest biomass residuesJacinto, Rodolfo Cardoso 20 February 2017 (has links)
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Previous issue date: 2017-02-20 / The objective of the present work was to determine the technical parameters for the
compaction and the quality of the pellets produced from different types of forest biomass and
residual agricultural biomass. The choice of the types of biomass was based on the production
volume of the main agricultural and forestry crops of the State of Santa Catarina, and the
economic, social and environmental importsnce of the same for the segments that produce
them. In this way, the physical, chemical and energetic properties of four types of agricultural
and forest residual biomass (Pinus chip, apple pruning branches, pinyon faults and araucaria
grimpa) were used to produce the pellets. Thirteen treatments in the study were analyzed,
consisting of pellets produced with: 100% pinus (P100), considered as a control treatment;
75% pinus and 25% of one of the analyzed residues (F25P75, when the residue was pinion
failure, G25P75, for the treatment containing grimpa, and Pm25P75, when the treatment had
apple pruning); 50% of pine and 50% of other analyzed components, being F50P50 (for
pinion failure), G50P50 (grimpa) and Pm50P50 (apple pruning); (F100P25), G75P25
(Grimpa) and Pm75P25 (apple pruning) and the homogeneous treatments with 100% of
failure (F100); 100% grimpa (G100) and 100% apple pruning (Pm100). For each treatment
was established for the ideal parameters of temperature, pressure and compaction of the
pellets produced in laboratory pelletizer. These data were established based on the physical
and chemical properties of biomasses in nature and also on the quality of the non-process
obtained pellet by means of successive compaction tests. After production of the pellets a
quality of this biofuel was determined by its physical, mechanical, chemical and energetic
properties. From the results obtained in the laboratory, pellets were classified based on the
quality criteria of ISO 17225-2 for biomass pellets for energy generation. It was concluded
that the treatments F75P25, G75P25 G50P50 and G25P75 were the only ones that reached
quality for residential and commercial use. The treatment with better quality for residential
and commercial use was treatment G25P75. The treatments Pm100, Pm75P25, Pm50P50,
Pm25P75 and G100 did not achieve average ratings in relation to ISO 17225-2 for any quality category described in the standard / O objetivo do presente trabalho foi determinar os parâmetros técnicos para a compactação e a
qualidade dos pellets produzidos a partir de diferentes tipos de biomassa florestal e agrícola
residual. A escolha dos tipos de biomassa foi baseada no volume de produção dos resíduos
das principais culturas agrícolas e florestais do Estado de Santa Catarina, e da importância
econômica, social e ambiental dos mesmos para os segmentos que os produzem. Desta forma,
foram caracterizadas as propriedades físicas, químicas e energéticas de quatro tipos de
biomassas residuais agrícolas e florestais (maravalha de pinus, galhos de poda de macieira;
falhas de pinhão; grimpa de araucária) que foram utilizadas para a produção dos pellets.
Foram analisados 13 tratamentos no estudo, que consistiram de pellets produzidos com: 100%
de pinus (P100), considerado como tratamento testemunha; 75% de pinus e 25% de um dos
resíduos analisados (F25P75, quando o resíduo era a falha de pinhão, G25P75, para o
tratamento contendo grimpa, e Pm25P75, quando o tratamento possuía poda de maça); 50%
de pinus e 50% de outro componente analisado, sendo F50P50 (para falha de pinhão),
G50P50 (grimpa) e Pm50P50 (poda de maça); misturas contendo 25% de pinus e 75% do
outro resíduo analisado, sendo F75P25 (falha de pinhão), G75P25 (grimpa) e Pm75P25 (poda
de maça) e os tratamentos homogêneos com 100% de falha (F100); 100% de grimpa (G100) e
100% de poda de maça (Pm100). Para cada tratamento foram estabelecidos os parâmetros
ideais de temperatura, pressão e velocidade de compactação dos pellets produzidos em
peletizadora piloto de laboratório. Estes parâmetros foram estabelecidos com base nas
propriedades físicas e químicas das biomassas in natura, e também em função da qualidade
do pellet obtido no processo, por meio de testes de compactação sucessivos. Após a produção
dos pellets foi determinada a qualidade deste biocombustível por meio de suas propriedades
físicas, mecânicas, químicas e energéticas. A partir dos resultados obtidos em laboratório, os
pellets foram classificados com base nos critérios de qualidade da norma ISO 17225-2 para
pellets de biomassa para geração de energia. Concluiu-se que os tratamentos F75P25, G75P25
G50P50 e G25P75 foram os únicos que atingiram qualidade para uso residencial e comercial.
O tratamento com melhor qualidade para uso residencial e comercial foi o tratamento
G25P75. Os tratamentos Pm100, Pm75P25, Pm50P50, Pm25P75 e G100 não conseguiram
classificações médias em relação a ISO 17225-2 para nenhuma categoria de qualidade
descrita na norma
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