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1

Kaplan, Haylee. "Assessing the invasiveness of Acacia stricta and Acacia implexa : is eradication an option?" Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20397.

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Thesis (MSc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: This thesis investigates the invasiveness and current status of two Acacia species recently identified as invaders in South Africa in order to determine the feasibility of their eradication. Australian acacias are among South Africa’s worst invasive species and many have had widespread damaging impacts on native ecosystems. In addition, several Acacia species still exist as small isolated populations in the country and have been targeted for eradication in order to prevent potential widespread impacts. This work assesses Acacia implexa (Chapter 2) and Acacia stricta (Chapter 3) as potential eradication targets by quantifying the extent of their invasion in South Africa, assessing the risk they pose to the country and evaluating the feasibility of their eradication based on estimated costs of clearing. Results of formal risk assessments show that both A. implexa and A. stricta should be considered high risk species, and bioclimatic model predictions indicate that both species have large potential ranges in South Africa. Detailed population surveys found that A. implexa and A. stricta each occur at several distinct localities all in the Western Cape Province. Acacia implexa populations were found at three sites (Tokai, Wolseley and Stellenbosch) where they have densified by means of vegetative suckering allowing A. implexa to outcompete native vegetation. No evidence of large seed banks of A. implexa were found, however vigorous resprouting following damage makes the control of A. implexa difficult. Acacia stricta was found at nine localities all in the Knysna area of the Garden Route, where populations are spreading along disturbed roadsides in plantations. Acacia stricta produces large amounts of seeds and can accumulate large seed banks. Seed spread is most likely due to large-scale soil movement by road maintenance vehicles which can easily lead to the establishment of new populations. We therefore used a predictive risk mapping approach based on the association of A. stricta to roadsides and disturbed plantations to enable effective searching to detect all infestations of A. stricta. Based on the high risk of both species and the limited range sizes of the currently known populations, we recommend that A. implexa and A. stricta remain targets for eradication. Management strategies proposed for these species (Chapter 4) include clearing on an annual (in the case of A. stricta) or biannual (for A. implexa) basis to prevent seed production, and targeted awareness campaigns at a national scale to determine whether our current knowledge of the extents of A. implexa and A. stricta are accurate. This work has shown that detailed assessments of species at intermediate stages of invasion is an important initial step in an eradication attempt, and better understanding of species specific invasion characteristics can help to improve management and potentially increase the probability of success of eradication.
AFRIKAANSE OPSOMMING: Hierdie tesis ondersoek die invasieve en die huidige status van twee Acacia spesies onlangs geïdentifiseer as indringers in Suid-Afrika ten einde die lewensvatbaarheid van hul uitwissing om te bepaal. Australiese akasias is onder Suid-Afrika se ergste indringerspesies en baie het wydverspreide skadelike impak op die inheemse ekosisteme. Verder het verskeie Acacia spesies bestaan nog steeds as 'n klein geïsoleerde bevolkings in die land en wat geteiken is vir uitwissing in om moontlike grootskaalse impakte te voorkom. Hierdie werk beoordeel Acacia implexa (Hoofstuk 2) en Acacia stricta (Hoofstuk 3) as 'n moontlike uitwissing teikens deur die kwantifisering van die omvang van hul inval in Suid-Afrika, die beoordeling van die risiko wat hulle inhou vir die land en die evaluering van die haalbaarheid van hul uitwissing op grond van beraamde koste van die wiele ry. Resultate van formele risikobepalings toon dat beide die A. implexa en A. stricta moet oorweeg word om 'n hoë risiko spesies, en bioclimatic model voorspellings dui daarop dat beide spesies het 'n groot potensiaal bereik in Suid-Afrika. Uitgebreide bevolkings opname gevind dat A. implexa en A. stricta elk by verskeie afsonderlike plekke in die Wes-Kaap voorkom. Acacia implexa is op drie plekke (Tokai, Wolseley en Stellenbosch) gevind, waar hulle deur middel van vegetatiewe suier densified en inheemse plantegroei oorwin het. Geen bewyse van groot nageslag banke van A. implexa is gevind, maar in kragtige resprouting volgende skade maak die beheer A. implexa moeilik is. Die Acacia stricta is op nege plekke in die Knysna-omgewing van die Tuinroete, waar die bevolkings verspreiding langs die versteurde paaie in plantasies. Acacia stricta produseer groot hoeveelhede saad en kan versamel groot saadbanke. Saad versprei is waarskynlik te danke aan grootskaalse grond beweging deur die instandhouding van paaie voertuie wat kan lei tot die vestiging van nuwe bevolkings. Ons het dus 'n voorspellende risiko kartering benadering wat gebaseer is op die vereniging van A. stricta aan paaie en versteurde plantasies in staat te stel om doeltreffend te soek alle besmettings van A. stricta op te spoor. Gegrond op die hoë risiko van beide spesies en die beperkte reeks groottes van die bevolking wat tans bekend is, beveel ons aan dat A. implexa en A. stricta bly teikens vir uitwissing. Bestuurstrategieë vir hierdie spesies (Hoofstuk 4) voorgestel word, sluit in die skoonmaak op 'n jaarlikse (in die geval van A. stricta) of die halfjaarlikse (vir A. implexa) basis van die saad produksie, en geteikende bewusmakingsveldtogte om te voorkom dat 'n nasionale skaal om te bepaal of ons huidige kennis van die omvang van A. implexa en A. stricta akkuraat is. Hierdie werk het getoon dat uitgebreide aanslae van spesies op intermediêre fases van die inval is 'n belangrike eerste stap in 'n poging van die uitwissing, en 'n beter begrip van spesies spesifieke inval eienskappe kan jou help om te verbeter en potensieel verhoog die waarskynlikheid van sukses van die uitroeiing nie.
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2

Joubert, Carinne. "Rhizobia associated with Australian Acacia species (Acacia mearnsii, Acacia dealbata and Acacia decurrens) in South Africa as determined by Sodium Dodecyl-Sulphate Polyacrylamide Gel Electrophoresis." Pretoria : [S.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-10052005-123519/.

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3

Ali, Marina, University of Western Sydney, and School of Civic Engineering and Environment. "Antimicrobial metabolites from Australian Acacia." THESIS_XXXX_CEE_Ali_M.xml, 1998. http://handle.uws.edu.au:8081/1959.7/216.

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As part of an investigation into traditional Australian Aboriginal bush medicine a range of Acacia species have been examined. Several species have been reported to be utilised for the preparation of antimicrobial washes and lotions by Aboriginal tribes. Initial bioactivity screening focussed on antimicrobial activity of the polar/and or non-polar extracts of air dried plant material, and a range of interesting activity has been found. Specifically, of the 94 extracts of Acacia species screened, five showed activity against the fungus C.albicans, 47 showed activity showed activity against the gram positive bacteria S.aureus and five showed activity against the gram negative bacteria E.coli. A retrosynthetic analysis and total synthesis of the novel anisidine alkaloid isolated from Acacia trineura was attempted. A variety of methodologies to generate the lithiate of anisidine and subsequently trap with an appropriate electrophile were attempted. While the results only indicated which methods were appropriate, they did give strong leads for future work in this direction
Doctor of Philosophy (PhD)
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4

Ali, Marina. "Antimicrobial metabolites from Australian Acacia." Thesis, View thesis, 1998. http://handle.uws.edu.au:8081/1959.7/216.

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As part of an investigation into traditional Australian Aboriginal bush medicine a range of Acacia species have been examined. Several species have been reported to be utilised for the preparation of antimicrobial washes and lotions by Aboriginal tribes. Initial bioactivity screening focussed on antimicrobial activity of the polar/and or non-polar extracts of air dried plant material, and a range of interesting activity has been found. Specifically, of the 94 extracts of Acacia species screened, five showed activity against the fungus C.albicans, 47 showed activity showed activity against the gram positive bacteria S.aureus and five showed activity against the gram negative bacteria E.coli. A retrosynthetic analysis and total synthesis of the novel anisidine alkaloid isolated from Acacia trineura was attempted. A variety of methodologies to generate the lithiate of anisidine and subsequently trap with an appropriate electrophile were attempted. While the results only indicated which methods were appropriate, they did give strong leads for future work in this direction
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5

McDougal, Fiona Janet. "Studies on gum exudates, with particular reference to gum Arabic (Acacia senegal) and other Acacia species." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/11112.

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6

Widiatmoko. "Oxygen delignification process chemistry for Acacia." Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-10212006-130331/.

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7

Forster, Michael Anthony Biological Earth &amp Environmental Sciences Faculty of Science UNSW. "The ecology of heteroblasty in Acacia." Awarded By:University of New South Wales. Biological, Earth & Environmental Sciences, 2009. http://handle.unsw.edu.au/1959.4/44100.

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Heteroblasty defines a dramatic change in leaf form and function along a shoot and is a prominent feature of the genus Acacia (Mimosaceae). Function of different leaf types in Acacia (i.e. compound leaf versus phyllode) is well established yet it is unknown whether heteroblasty is a plastic trait. A fully factorial designed experiment established the light environment, and not nutrients or water, had a significant influence on heteroblastic development. Compound leaves, which have higher specific leaf area (SLA), are retained for longer under low irradiance and, specifically, under a low Red:Far Red light environment. Plants grown in high intraspecific density environments also retained compound leaves for longer. Blue light signals and greater ultraviolet radiation had no effect on heteroblastic development. Heteroblasty is thought to aid in seedling establishment however across all experiments there was no consistent evidence of improved plant performance. Rather, there was an optimal allocation of biomass to organs where resources were most limiting and this was more influential in assisting seedling establishment. Lastly, a meta-analysis of a global dataset of leaf traits found compound leaves to be similar to simple leaves but offset towards the cheap to construct with fast returns region of the leaf economics spectrum.
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8

Oballa, Phanuel O. "Genetic variation within Acacia karroo Hayne." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334928.

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9

Ali, Marina. "Antimicrobial metabolites from Australian Acacia : thesis /." View thesis, 1998. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030825.144902/index.html.

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10

Sornsathapornkul, Prasert. "Reproductive biology of a tropical Acacia hydrid, Acacia mangium Willd. x A. auriculiformis A. Cunn. ex Benth." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0022/NQ32727.pdf.

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11

Kawamata, Yoshiyuki R. "Environmental effects on the ecophysiology and morphology of Acacia species /." [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16328.pdf.

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12

Odei-Addo, Frank. "Purification and characterization of serine proteinase inhibitors from two South African indigenous plants, Acacia karoo and Acacia schweinfurthii." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1291.

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Serine proteases are known to perform a wide range of functions essential to life; however there has to be some form of control mechanism in place. One of the many control mechanisms is their specific inhibition by protein proteinase inhibitors. Proteinase inhibitors in plants, present in their seeds, participate in defense mechanisms and their production is induced by herbivory or wounding. Plant proteinase inhibitors have been reported to inhibit a variety of serine proteinases, including enzymes of the blood coagulation cascade. In this study, various indigenous seed extracts were screened for potential serine proteinase inhibition. Acacia schweinfurthii was selected as a potential inhibitor that inhibited trypsin and factor X. The AS inhibitor was successfully purified to homogeneity by precipitating with 80 percent (v/v) acetone and the sequential chromatographic steps including ion-exchange chromatography, size exclusion chromatography, affinity purification on a trypsin-agarose column and RP-HPLC. Reducing SDS-PAGE conditions revealed an inhibitor of two polypeptide chains A and B of approximate molecular weights 16 and 10 kDa, respectively, and under non-reducing conditions, 25 kDa was observed. The inhibitor was shown to inhibit trypsin, chymotrypsin and factor X indicating the dynamic nature of the reactive site. An enzyme: inhibitor ratio of 1:1, and a Ki of 3.45nM was determined for the AS inhibitor on trypsin, and the inhibitor also weakly inhibit chymotrypsin. AS inhibitor and STI inhibited factor X with a Ki values of 13.7nM and 77.5μM respectively. Amino acid analysis revealed Mmin values of the A- and B- chain of 15,000 and 7,800, respectively. The effect of seed extracts on the activated partial thrombin time (APTT) and prothrombin time (PT) was tested. No prolongation of the PT was obtained. For the crude extracts of AK and AS, IC200 values of 4.6 and 189.62 μg/mL, were respectively obtained. For the purified fractions of STI, AS and AK, IC200 values of 51.5, 114.31 and 893.8 μg/ml were observed, respectively. Keywords: proteinase inhibitors, Acacia species, trypsin inhibitor, FX inhibitor.
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13

Antunes, Fernanda Schablatura. "Avaliação da qualidade da madeira das espécies Acacia crassicarpa, Acacia mangium, Eucalyptus nitens, Eucalyptus globulus e Populus tremuloides." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-23062009-094257/.

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As madeiras utilizadas para produção de polpa celulósica podem ser divididas em dois grupos em função da fibra: folhosas (fibra curta) e coníferas (fibra longas), as espécies de folhosas são destinadas especialmente a papéis de escrita e impressão. As principais espécies de folhosas utilizadas para produção de polpa de fibra curta em outros países são o Eucalyptus globulus (Península Ibérica e Chile), Eucalyptus nitens (Chile), Populus tremuloides (Canadá), Acacia mangium, Acacia crassicarpa (Indonésia). Este projeto tem por objetivo: avaliar e comparar o desempenho de madeiras utilizadas mundialmente para produção de polpa celulósica de fibra curta considerando parâmetros de qualidade da madeira tais como composição química, densidade básica, características anatômicas da madeira; com objetivo de fornecer informações estratégicas para o setor nacional de celulose e papel, visando o conhecimento e posicionamento em competitividade destas madeiras no mercado mundial. Para a realização deste trabalho foram coletadas 5 árvores de cada espécie as quais foram utilizados cavacos cortados manualmente obtidos de discos; com relação à madeira foram determinadas densidade básica, composição química e dimensões de fibras. Os resultados foram analisados estatisticamente sendo comparadas as diferentes espécies referentes à qualidade da madeira.
Wood used for pulp production may be divided in two major groups regarding fiber function: hardwood (short fiber) and softwood (long fibers). Hardwood species are mainly designated to writing and printing papers. Hardwood principal species used for production of short fiber pulp in other countries are Eucalyptus globulus (Iberian Peninsula and Chile), Eucalyptus nitens (Chile), Populus tremuloides (Canada), Acacia mangium and Acacia crassicarpa (Indonesia). This study aimed to evaluate and compare the performance of the main woods used worldwide for short fiber pulp production regarding wood quality parameters such as chemical composition, basic density and wood anatomical properties, in order to provide strategic information for national pulp and paper industry, aiming the knowledge and competitiveness of these woods at worldwide market. To accomplish this study, 5 trees from each species were collected and wood chips were manually cut. In relation to the wood, basic density, chemical composition and fiber lengths were determined. The results were statistically analyzed and the different species were compared regarding wood quality.
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14

Grosso, Bernadette. "Contribution a l'etude phytodermologique du genre acacia." Toulouse 3, 1988. http://www.theses.fr/1988TOU30157.

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15

Grosso, Bernadette. "Contribution à l'étude phytodermologique du genre Acacia." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376140503.

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16

Jasson, René. "Management of Acacia species seed banks in the Table Mountain National Park, Cape Peninsula, South Africa /." Link to the online version, 2005. http://hdl.handle.net/10019/1059.

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17

Gaol, Mangadas Lumban. "Ecological study of plant species at Sandford Rocks Nature Reserve (SRNR)." Thesis, Curtin University, 2002. http://hdl.handle.net/20.500.11937/234.

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The ecology of plant species at Sandford Rocks Nature Reserve (SRNR) was studied. The study site is an important nature reserve that contains relatively undisturbed natural vegetation. It has a mosaic of exposed granite rocks, scrublands and woodlands. The study involved: a description of the structure and composition of the vegetation; the population characteristics of selected Acacia species; aspects of reproduction in Acacia; germination and seedling characteristics of some Acacia and grass species that dominate the reserve; the effect of seed size on germination and seedling characteristics; and, the relationship of seed size to seed coat thickness in selected Acacia species. Five different areas were studied using the point centered quarter method to sample the woody perennial species. Thirteen Acacia species were examined for reproduction characteristics; and in 2 selected Acacia species, the effects of phyllode and/or inflorescence removal on reproduction was investigated. Germination tests were conducted to identify germination characteristics in 8 Acacia and 7 grass species dominant at SRNR. The possible effects of variation in seed size on germination; seedling characteristics; and, seed coat thickness were investigated in Acacia fauntleroyi and Acacia prainii. A total of 85 species from 20 families of woody perennials were collated. All areas were dominated by the Myrtaceae, Mimosaceae and Proteaceae families. There was considerable variability in the structure and composition of vegetation. Most species were present in particular sites and the composition of communities appears to be related to the heterogeneity of the habitat within the reserve. In areas of shallow or rocky soil, vegetation types present include Allocasuarina huegeliana woodland, Grevillea paradoxa low scrubland and Acacia neurophylla medium shrubland.In a seasonally wet area, vegetation types present include low open grassland; Eucalyptus capillosa (wandoo) woodland; and, Acacia saligna thicket. In deep, dry sandy soil, vegetation types include Phebalium tuberculosum shrubland, Acacia acuminata and Acacia coolgardiensis thickets. On relatively flat areas that gain water from adjacent large granite hills, the vegetation consists mainly of tall, open woodlands of Eucalyptus species. Vegetation types include: medium tall Eucalyptus salmonophloia woodland with Kunzea pulchella shrubland at the periphery of the Eucalyptus woodland. At rock areas, vegetation types present include dense Leptospermum erubescens thicket, low open Acacia prainii and Dodonaea viscosa shrubland. Of the Acacia populations studied, in A. lasiocalyx no recent seedling establishment was observed. It is hypothesised that recruitment occurs in particular periods. As the plants are associated with rock and soils are generally shallow, it appears that recruitment depends on run-off water from the rocks in winter. Continuous recruitment seems to be the pattern in A. prainii with both seedlings and saplings represented. A. fauntleroyi forms relatively small populations; apparently long drought periods (>l00 d) result in mass death and limit its population size. In A. hemiteles, no seedling stage was found, root competition (for water) from associated Eucalyptus species presumably limits its recruitment. Reproductive success of Acacia is affected by rainfall. A wet winter is required to induce flowering and further rain is required after flowering to promote pod development and good seed set.All Acacia species suffer from drought in the reproduction season, however they differ in their degree of susceptibility. Leaflessness and tree shape also affect Acacia fecundity. Plants bearing more phyllodes produce more flowers and pods, and branches in the upper part of the crown bear heavier inflorescences. In 1998, all Acacia species at SRNR produced mature seed of low weight, with many immature and diseased seed, which gave poor germination. A late spring frost in 1998 is believed to be responsible for limited seed development. In two selected Acacia species, removal of phyllodes reduced the number of pods produced. Presumably, phyllode removal reduces photosynthate produced, therefore the competition among inflorescences (or pods) for resources is more intense and subsequent abortions are likely to occur. All Acacia species studied showed best germination in the cool winter temperature range. Apparently, seeds are adapted to germinate in winter when seasonal moisture is more likely to be available. The best temperature however, varied slightly between species. The grass species dominant in the reserve, except for Aristida contorta, also had more germination in cooler rather than warmer temperatures. The flora of SRNR is similar to typical vegetation of the Southwest. Generally, Acacia species are present only in particular sites, presumably were habitat moisture allows. Seedlings of Acacia species growing in naturally dry areas have greater root: shoot masses than those growing in seasonally wet areas. Biomass partitioning is an apparent strategy to conserve water. Of the 7 grass species, Amphipogon strictus appears to have fastest growth.Eriachne ovata has greater root than shoot mass, while in all other species, shoot mass is greater than root mass; a characteristic of species that grow well in moist habitats. The longest shoots and roots are in Austrostipa elegantissima, an understorey species of eucalypt woodland. In A. fauntleroyi, the degree of hard-seededness varies between seed sizes. There is a higher proportion of soft seed in smaller seed. Seed of different sizes show some responses to different pre-treatments and incubation temperatures for germination. Larger seeds generally germinate in greater numbers after higher treatment temperatures. The best treatment for small seeds is pre-treatment at 75°C and incubated at 15°C. For medium and large seed, best pre-treatment is at 75°C with incubation at 30°C or soaking in boiling water and incubation at either 15 or 3°C. In A. prainii, seed size; pre-treatment; incubation; and, their interaction all affected germination; larger seeds are more viable. The best treatment to promote germination of A. prainii is soaking in boiling water and incubation at 25°C. In both A. fauntleroyi and A. prainii, larger seeds produce larger seedlings. Seedlings from large seeds have the potential for more rapid pre-photosynthetic growth. Larger, heavier seed has a thicker seed coat. The seed coat of A. prainii is thicker than in A. fauntleroyi; the difference in seed coat thickness is reflected by more soft seed in A. fauntleroyi (35%) than in A. prainii (6%).
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Marques, Filipe Alexandre de Andrade. "Contribuição para o conhecimento da capacidade e vigor germinativos de sementes de Acacia dealbata Link. e Acacia longifolia (Andr.) Wild." Master's thesis, ISA, 2014. http://hdl.handle.net/10400.5/6794.

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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
The aim of this study was to improve the knowledge on seed-coat dormancy and germination skills of Acacia, seeking to clarify key aspects relating to the efficiency of its expansion through seed propagation. The species, Acacia longifolia (provenance: Sintra) and A. dealbata (provenances: Fundão and Cabrum river valley), are considered two of the most invasive of its genus in Portugal. For both species two seed propagation tests were performed: one for pre-germination treatment and another for germination in nursery environment. In these trials, we determined the weight of seeds, the germination rate and the vigor index; hot water (90° C followed by 24 hour immersion) was used to break the seed-coat dormancy. In the experiment performed in the nursery the two species were also compared for the rate of mortality, and for vitality through the determination of chlorophyll fluorescence. The results indicated that Acacia longifolia has a higher fitness than A. dealbata to seed propagation. This capability was confirmed by a potential germination in chamber significantly higher than that of A. dealbata, by a higher germination rate in nursery and higher vitality of seedlings produced, measured by a post-germinative mortality rate significantly lower.
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RODRIGUEZ, GOMEZ AGUSTIN. "Actividad ovicida y larvicida in vitro del extracto hidro-alcoholico de Acacia cochliacantha en Haemonchus contortus." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2016. http://hdl.handle.net/20.500.11799/65067.

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medicina alternativa, control de nemátodos gastrointestinales en rumiantes
En la actualidad se han comprobado efectos antihelmínticos de extractos acuosos de las leguminosas, por lo que en el presente trabajo de investigación se evaluó el extracto hidro-alcohólico (EHA) de Acacia cochliacantha, sobre la inhibición de la eclosión de huevos (IEH) y mortalidad de larvas infectantes L3 (MLI, %), del nematodo Haemonchus contortus como modelo biológico. El diseño experimental utilizado fue un completamente al azar, para probar las siguientes concentraciones 100, 90, 80, 70, 60 y 50; 200, 175, 150, 125 y 100 mg mL-1 para IEH y MLI, respectivamente. Los resultados se analizaron con la prueba de PROBIT del sistema SAS (2006). Las concentraciones letales para IEH fueron: CL50: 66.01 y CL90: 98.23 mg/ml) y las concentraciones letales del porcentaje de mortalidad de larvas infectantes (%MLI) fueron de: (CL50 127.39 mg/ml y CL90 177.88 mg/ml) respectivamente. El extracto hidro-alcohólico (EHA) de la leguminosa Acacia cochliacantha tiene efectos antihelmínticos en las dos fases exógenas del nematodo Haemonchus contortus.
CENTRO UNIVERSITARIO UAEM TEMASCALTEPEC, INIFAP MORELOS-CENID PARASITOLOGIA VETERINARIA
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20

Shafiq-ur-Rehman. "Physiological responses of acacia seeds to salt stress." Thesis, Coventry University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363856.

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Raine, Nigel. "The pollination ecology of a Mexican Acacia community." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393473.

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Osman, Mohamed Elmubarak. "Fractionation and characterisation of gum from Acacia senegal." Thesis, University of Salford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336168.

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23

Galiana, Antoine. "La symbiose fixatrice d'azote chez acacia mangium - rhizobium." Paris 6, 1990. http://www.theses.fr/1990PA066516.

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Quarante deux souches de rhizobium ont ete isolees de nodules d'acacia mangium recoltes dans l'aire d'origine (australie) et dans diverses zones d'introduction de l'espece. La caracterisation de ces souches a montre qu'elles appartenaient toutes au genre bradyrhizobium. Les souches originaires d'australie presentent une effectivite superieure aux souches d'autres origines ou aux souches de collection isolees chez d'autres especes. Nous avons tente d'etablir une relation entre les quantites d'aia et de cytokinines produites par trois souches (aust 13c, tal 72, ors 800) ex-plants et celles contenues dans les nodules formes par ces souches. Les nodules formes par la souche aust 13c ont une teneur en zr, ip et ipa deux a trois fois plus elevee que ceux formes par les autres souches. Ceci pourrait etre lie a une activite meristematique et une activite fixatrice d'azote prolongees de ces nodules. La troisieme partie de notre etude concerne l'amelioration de la fixation de l'azote par selection clonale d'a. Mangium. Apres la mise au point d'une technique de micropropagation conforme (stimulation du bourgeonnement axillaire de jeunes explants de tiges), cinq clones ont pu etre selectionnes a un stade precoce en fonction de leur potentiel fixateur d'azote. L'inoculation de cinq clones avec trois souches de bradyrhizobium sp. D'effectivites variables montre que: (1) le potentiel fixateur d'azote des clones est conserve quelle que soit la souche testee; (2) l'effectivite des trois souches varie dans le meme sens quel que soit le clone considere. L'effet de l'interaction souche x clone n'etant pas significatif, les partenaires de la symbiose peuvent etre selectionnes separement. Les essais d'inoculation d'a. Mangium au champ sur differents types de sol (benin, iles cook et cote d'ivoire) ont montre un effet positif de l'inoculation sur la nodulation et la croissance des plants plus d'un an pres transplantation au champ. Ils ont egalement confirme l'effectivite superieure des souches d'a. Mangium d'origine australienne par rapport aux autres souches testees
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24

Skowno, Andrew L. "The successional dynamics of Acacia nilotica (L.) savanna." Bachelor's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/25778.

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Analysis of aerial photographs indicates that woody plant biomass has increased in Hluhluwe Game Reserve, KwaZulu Natal, over a relatively short period. Despite their slow growth rates, Eucleas and other broadleaf species are responsible for the majority of this increase. Nine sites were chosen to examine the recruitment patterns and sizeclass distributions of Euclea divinorum and E. racemosa. Analysis of the size-class distribution data suggests that recruitment of Eucleas is slightly higher below adult A. nilotica canopies than in adjacent interspaces. The number of seedlings is significantly higher below Acacia canopies than in open spaces. Size class data indicate that the largest Euclea individuals are found in open spaces and not below A. nilotica canopies. Because Eucleas have slower growth rates than A. nilotica, the large Eucleas may well have become established before the present A. nilotica stand. The data also indicate that A. karroo is replacing A. nilotica and that broadleaf species other than Eucleas are recruiting in both open and below canopy plots. I suggest A. nilotica adults only weakly facilitate the establishment of Eucleas and other broadleaved species, and that increase in woody vegetation is due to changes in the fire regime that allow suppressed broadleaf individuals to escape and become visible. This release may explain the rapid rate of encroachment by inherently slow growing species.
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25

Staver, A. Carla. "Spatial and temporal variability in Acacia population dynamics." Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/6214.

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Includes bibliographical references (p. 130-141).
Variability in fire, herbivory, and climate facilitate the coexistence of trees and grasses in savannas and impact upon savanna structure, which also varies substantially both spatially and temporally. These features can shape savannas at an ecosystem and even at a global scale, but mechanisms for the effects of fire, herbivory, and climate variability on tree cover are often demographic at the tree population level. Sapling growth in particular has repeatedly been shown to be the limiting step, or 'bottleneck', in the establishment of trees in savannas. I set out to investigate how spatial and temporal variability in fire, herbivory, and climate shape population dynamics of a suite of common African savanna trees, the Acacia, in a landscape context. I carried out my field work in Hluhluwe iMfolozi Park in K waZulu Natal, South Africa, during 2006 and 2007. Fire, herbivory, and the grass layer were primary determinants of distributions and co-occurrence of Acacia species.
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26

Majalap, Noreen. "Effects of Acacia mangium on soils in Sabah." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU118277.

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Soil changes occurring under A. mangium were studied by comparing soil chemical properties between A. mangium plantations and adjacent non- A. mangium areas, both on a regional and a local scale. Soil pH, exchangeable base cations (especially Ca), and base saturation decreased under A. mangium while exchangeable acidity and Al increased. Translocation of base cations down the soil profile was shown by a decrease in their concentrations in the upper parts of the soil profile and an increase at depths. This appears to be related to an increase in organic C and N content in the lower soil horizons. Solute chemistry and fluxes in precipitation, throughfall, stemflow and in the forest floor, at 30 and 60 cm soil depth were studied. Rates of litter production, litter decomposition and N-mineralization were also quantified. Canopy interception of precipitation was high (20%) resulting in retention of most of the solutes. These, however, were later released in considerable amounts from the forest floor. Dissolved organic C showed the highest flux from the forest floor. Litter production was high under A. mangium at 12 t ha-1 yr-1 while leaf litter decomposition rate was relatively low at 0.45 yr-1 suggesting that forest floor as a significant source of organic acids. While considerable NO3-N flux from the forest floor was also seen, concentration of NO3-N was highest in the surface mineral soil. Soil nitrification rate was estimated as 17.7 g g-1 30 d-1 for the 0-15 cm depth. In a laboratory soil leaching experiment, interactions of throughfall and stemflow solutions with A. mangium litter caused significant changes in the soil chemical properties. Retention of DOC in the soil plus the continual increase in leachate pH suggest enhanced weathering. Increase in soil pH, exchangeable bases and base saturation was observed suggesting that in the short term A. mangium results in 'ameliorative' effects on the soils, but may be deleterious in the long-term especially on highly weathered soils.
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27

Waldon, Hollis B. "Sonoran Desert Rhizobia Found to Nodulate Acacia constricta." University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/554231.

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28

Misran, Suffian. "Factors affecting the enhancement of Acacia hybrid particleboard." Thesis, Bangor University, 2011. https://research.bangor.ac.uk/portal/en/theses/factors-affecting-the-enhancement-of-acacia-hybrid-particleboard(62a55acc-e15a-48f2-b4d7-543f9ba74f8c).html.

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29

Hamouda, Yasir. "Factors affecting the quality of Acacia senegal gums." Thesis, University of Chester, 2017. http://hdl.handle.net/10034/620895.

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Gum arabic is a natural gummy exudate from acacia trees and exhibits natural built-in variations commonly associated with hydrocolloids. This study is concerned with the determination of factors which could influence its properties and functionality. These factors include origin (location, soil type, rainfall), different collections, age of the trees and storage condition. Previous studies acknowledged the influence of some of these factors but somehow lack providing definitive answers to questions being asked by the end user and required for the development of Gum arabic industry in Sudan. Local knowledge as well as the various stages of gum collection and processing were reviewed in order to provide a clear background and the justification for the experimental design. In this study samples were collected from six plantations located in the west and east regions in Sudan. Samples were collected from trees of different age (5, 10, 15 and 20 years old) and also from different picking interval (1-4). Each sample was divided into three portions (UK, Khartoum and Port Sudan) and stored for 5 years in order to determine the effect of the respective location. Various analytical parameters (% loss on drying, Optical rotation, % protein, intrinsic viscosity, molecular weight and molecular weight distribution) were measured to fully characterise the gum samples and to determine their functionality (emulsification). The results obtained for all samples were consistent with those previously reported in the literature (see Chapter 4). The only exception, identified in a number of samples from the western region, is the high proportion (~30%) of high molecular weight fraction termed arabinogalactan-protein complex (AGP). The results clearly demonstrated significant variations between plantations located in western region compared with the eastern region. However, the variations between the plantations within the same region are statistically not significant. High values of % protein, viscosity, Mw and % AGP were obtained from the 1st pick, from both regions, and then significantly decreased thereafter to the fourth pick. Samples from west region in Sudan, from 1st and 2nd pick and from tree age (15) years gave the highest viscosity, molecular weight, % AGP and superior emulsification performance compared to other samples from different tree ages. The regression statistical analysis for the physiochemical properties correlation with emulsification performance demonstrated the role of % AGP to be the most influential factor followed by viscosity. The major finding of this study is the effect of storage condition on the properties and functionality of Acacia senegal. An increase in the molecular weight for all stored samples (for 5 years) irrespective of region was evident and statically significant. However, this increase was more prominent for samples from the western region compared to the eastern region. The AGP fraction was increased by the storage treatment up to 40% in Port-Sudan, 20% in Khartoum-Sudan and 15% in UK. The result clearly demonstrated that the temperature and humidity are the crucial factors to induce the natural maturation process in acacia gums. Statistical analysis (linear regression) suggested statistically significant models and equations to predict and explain the variations in the physiochemical and functional properties based on the environmental factors, picking set and age of the tree.
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Wardill, Trevor James. "Genetic diversity in the biological control process : Acacia nilotica as a test case /." [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19170.pdf.

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31

Avoseh, Opeyemi Nudewhenu. "Isolation, characterisation of terpenoids and biosynthesis of silver nanoparticles of acacia mearnsii de wild and acacia Karroo Hayne and their Bioassays." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/d1021292.

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Great wealth of traditional knowledge about the use of plants had been transferred from generation to generations leading to the present day drug discovery and invention of new scientific methods of isolation, purification and identification. With the discovery of new diseases and drug-resistant organisms, there is no other source or deposit of lead compounds or drugs than the plant kingdom. As a result of this, about 25% of the current drug administered owe their origin to plant sources with the view to reduce the carcinogenic effect of synthetic drugs. Volatile terpenoids among other broad spectrum of natural product had been implicated to show high therapeutic properly. In the present study, selected locally-used medicinal plants were exploited for the presence of potent bioactive compounds and ability to form nanoparticles with distinctive property for use as chemoprotective agent against inflammation, tumors, cancer and other chronic diseases. Acacia mearnsii De Wild and Acacia karroo Hayne studied in this report are known to be invasive species with no proper regulation to conserve and preserve them. However, ethnopharmacology report of these plant species in the Southern Africa region reveals that they are good antiseptic, anti-diarrhea, anti-inflammation and a forage for livestock. These plants were subjected to volatile extraction protocol of some parts of the plants (stem and leaves) followed by examination of the anti-inflammation capacity of the extracts using an animal model. In addition, the bye-product (hydrosol) from the stem bark of each species possess a high reducing and stabilizing property leading to synthesis of silver nanoparticles, followed by investigation of the anti-inflammation potential of the synthesized silver nanoparticles using animal model. The volatile oils of the leaves and stem bark of Acacia mearnsii De Wild obtained by hydro-distillation were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Twenty, Thirty-Eight, Twenty-nine and Thirty-Eight components accounting for 93.8%, 92.1%, 78.5% and 90.9% of the total oils of the fresh, dry leaves and fresh, dry stem bark respectively. The major components of the oil were octadecyl alcohol (25.5%) and phytol (10.5%); cis-verbenol (29.5%); phytol (10.1%) and phytol (23.4%) for the fresh leaves, dried leaves, and fresh stem, dry stem bark respectively. Oral administration of essential oils at the dose of 2% showed significant (p<0.05) anti-inflammatory properties in the albumin induced test model in rats. Oils from the fresh leaves and dry stems inhibited inflammation beyond 4 h post treatment. Furthermore, the chemical composition of the essential oils obtained by hydro-distillation from the leaves and stem bark (dry and fresh) of Acacia karroo Hayne, analysed by GC-MS, shows that hexanal (10.67%) and ß-ionone (9.74%) were dominant in the dried leaves, β-pinene (14.30%), and (Z)-2-Hexen-1-ol (10.21%) in the fresh leaves while Octacosane (10.59%) and phytol (23.38%) were dominant in the dry and fresh stem respectively. The anti-inflammation ability of these oils after an albumin-induced inflammation on wistar rats, shows a significant effect at the 1st h of treatment with a significance of P< 0.01 for all part plants, while the fresh leaves shows further inhibitory activities at the 2nd h of analysis. Silver nanoparticles (AgNPs) were successfully synthesized from AgNO3 through a green route using the aqueous extract (hydrosols) of Acacia mearnsii De Wild and Acacia karroo Hayne as reducing agent and as well as capping agent. The Acacia-mediated AgNPs were characterized with the use of UV-vis absorption spectroscopy, Fourier Transform Spectroscopy (FT-IR), Transmission electron microscope (TEM), Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDX), and X-ray Diffractometry (XRD). A spherical, 10-40 nm diameter silver nanoparticles were synthesized with very low level of stability for the AMDS and the AKDS-AgNPs. In addition, nociceptive activity with a mice rat reveals higher inhibition at the neurogenic phase for the AKDS-AgNPs, while AMDS-AgNPs exhibited a high inhibition at the inflammatory phase. The potent anti-inflammatory activity of essential oils of A. mearnsii De Wild and A. karroo Hayne hereby confirmed its traditional use in treating various inflammatory diseases, while the inflammatory studies on the synthesized AgNPs reveals a very active compound which can be used as a potent opioid or non-steroidal anti-inflammatory drug (NSAID).
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32

Ang, Lai Hoe. "Effects of periodic drought on Acacia mangium Willd. and Acacia auriculiformis A. Cunn ex Benth growing on sand tailings in Malaysia." Thesis, University of Aberdeen, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320241.

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This study aims: 1) To quantify the factors affecting the changes of site water status of the high sand tailings, 2) To investigate the growth and physiological responses of Acacia mangium and A. auriculiformis to the fluctuations of site water status on high sand dunes, and 3) To identify characteristics which may allow the trees to adapt to and survive on high sand tailings. In both shade and open plots on sand tailings, diurnal air water deficits would be anticipated particularly in sunny days and late afternoon in cloudy days. The results from dipwell showed that the main source of soil water supply to the sand tailings is solely dependent on the rainfall and not from surrounding mining pools. Furthermore, at 6 d after rainfall <37 mm, sand tailings at 0-15 cm depth had low sand suction showing soil water deficit to plant uptake. Hence, the rainfall distribution would determine the growth of acacias in sand tailings. Dry periods significantly reduced (P<0.05) the shoot length and stem diameter growth rates and leaf area of both acacias. Dry periods also significantly increased leaf and branch number shedding rates of both acacias. Generally, shading did not improve the growth rates of both acacias in dry periods but significantly delayed leaf shedding of the two acacias in dry periods. A. auriculiformis had significantly higher shoot length and stem diameter growth rates as the result of higher leaf and shoot numbers. The superiority of A. auriculiformis compared to A. mangium in adapting to high sand tailings was explained by its growth patterns that had characteristics of drought avoidance, and/or tolerance. Greater vegetative growth was observed in A. auriculiformis than A. mangium in wet periods. The effects of atmospheric and soil water fluctuations on some physiological responses of the two species were also examined.
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33

Smythe, Keri-Ann. "Shifts in community structure over spatial and temporal gradients : the Acacia nilotica-Acacia karoo community in the Hluhluwe-Umfolozi Game Reserve." Thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25781.

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34

Mgidi, Theresa Nobuhle. "Attributes that make Acacia karroo dominant : stable N and C isotope analysis of nine Acacia species from KwaZulu-Natal (South Africa)." Master's thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/6138.

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Includes bibliographical references (leaves 53-67).
This study focuses on nine Acacia species from Hluhluwe-Imfolozi Park in KwaZulu-Natal, South AFrica. The study was motivated by the need to understand the dominance of legumes in the process of bush encroachment in Southern Africa. A. karroo has been identified as a particularly invasive species in HUP, and determining what makes this Acacia species and any of the other acacias in HUP invasive formed the foundation of this study.
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35

Ndlovu, Joice. "The invasion ecology of Acacia pycnantha : a genetic approach." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/96559.

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Thesis (PhD)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: Australian Acacia species are an important group of invaders and are known to form dense monospecific cultures in invaded habitats. Despite the ecological and economic importance of invasive acacias, little is known about their invasive biology both from an ecological and evolutionary perspective. Molecular genetic methods have increasingly become important in identifying source populations for invasive species and determining the population genetic structure of these populations. This thesis applied molecular tools to understand the invasion ecology of Acacia pycnantha and its rhizobial symbionts as a model system of Australian Acacia introductions. Specific objectives were to: reconstruct the molecular phylogeny of invasive and native populations of populations of Acacia pycnantha and identify the native provenance of A. pycnantha; identify microsatellite markers for Acacia pycnantha and other invasive Australian acacias based on transferring microsatellite markers developed for A. mangium, A. saligna, Paraserianthes lophantha and universal chloroplast microsatellites developed from tobacco; assess the introduction dynamics of Acacia pycnantha in South Africa and identify the source populations in the species’ native range ; and determine which nitrogen fixing symbionts nodulate A. pycnantha and determine whether A. pycnantha brought its symbionts along from its native range or acquired them in the invasive range. Nuclear and chloroplast DNA sequence data were used to reconstruct phylogeographic relationships between native and invasive A. pycnantha populations. The chloroplast phylogeny showed that Australian populations of A. pycnantha are geographically structured into two previously informally recognized lineages (representing wetland and dry land forms). Habitat fragmentation is probably the result of cycles of aridity and abundant rainfall during the Pleistocene0. The invasive population in Portugal was found to be the wetland form while South African populations were found to be predominantly wetland form although some dryland forms were identified. Thirty microsatellites out of the forty nine tested microsatellites successfully amplified across all species tested (A. implexa, A. longifolia, A. melanoxylon, A. pycnantha and A. podalyriifolia). High Transfer rates varied between 85% for microsatellites developed for A. mangium to 50% for those developed in A. saligna. Although transfer rates were high only twelve microsatellites (24%) out of the fifty tested were polymorphic while the chloroplast microsatellites showed no polymorphism. The low level of polymorphic loci calls for development of more microsatellites in this genus especially for species that have high commodity value. Nuclear microsatellites revealed three genetic groupings with substantial admixture in the native range (1. wetland Victoria and South Australia populations; 2. dryland Victoria and Flinders Range population; and 3. New South Wales). Admixture in the native range may have occurred as a result of reforestation exercises. Acacia pycnantha has been widely used in rea forestation projects in Australia because of its fast growth rate and ease of germination. Admixed populations were most - likely introduced to South Africa thus establishment of A. pycnantha may have been facilitated by already admixed propagules in the invasive range. Extensive admixture in the native range made it difficult to identify source populations of invasive A. pycnantha found in South Africa. The rhizobial symbionts of A. pycnantha were identified, showing that this species utilizes a wider suite of symbionts in its invasive range than its native range and there is support for both the co-introduction and host jumping hypotheses. This creates substantial opportunities for horizontal gene transfer between previously allopatric bacterial lineages, with as yet unknown consequences for plant and bacterial invasions.
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36

Howard, Delwyn M. "The value of Acacia saligna as a source of fodder for ruminants." Thesis, Curtin University, 2002. http://hdl.handle.net/20.500.11937/914.

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Three pen trials were conducted to evaluate the value of A. saligna as a source of feed for ruminants. In Trial 1 A. saligna was inadequate as the sole source of nutrients for sheep. Furthermore, the level of detannification achieved in Trial 1, with the addition of PEG 4000 or PEG 6000, failed to improve the diet sufficiently. The antinutritional effects on the animals were largely attributed to the excessive biological activity of the phenolics in the A. saligna leaves. Feeding of these leaves, without PEG, had a definite defaunating effect on the ruminal fluid. The ruminal ammonia levels were all well below the threshold for maximal microbial growth. Given the results of Trial 1, the second trial was undertaken to determine if A. saligna was more useful as a supplement rather than a basal diet. The benefits of including A. saligna as a supplement to a basal diet of lupins and wheat straw were not clear. The benefits of including a detannification agent with the A. saligna were also not evident. Ruminal ammonia levels were much higher than in Trial 1 and animals generally maintained weight. Trial 2 revealed that the sheep were capable of consuming significantly more A. saligna than they did in Trial 1, but it was not clear whether this was due to the basal diet providing adequate nutrients or if it was due to differences in the A. saligna fed in the respective trials. Total phenolics, CT and PPC were considerably lower than those of Trial 1. Trial 3 was designed to investigate the use of A. saligna as the basal source of nutrients, with or without a supplement of N in the form of urea or PEG. Total phenolics, CT and PPC were lower than those of Trial 1, but higher than those of Trial 2. Animals consumed more A. saligna than in Trial 2 and generally maintained weight.The results from Trial 3 suggest that A. saligna could be a useful feed source for ruminants. The substitution of straw with A. saligna indicates that its incorporation into a grazing system could significantly decrease grazing pressure on dry summer pastures. In Trial 3 goats were not shown to have a superior ability than sheep in utilising A. saligna as a source of nutrients.
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37

Haiden, Sarah. "Why do wasp induced galls of Acacia longifolia photosynthesise?" Bachelor's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/26375.

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While many stem and bud galls contain chlorophyll, and have the potential to photosynthesise, these insect-induced growths are generally thought to act as strong carbon sinks, manipulating the normal phloem transport of the host plant in order to serve the demands of the galling herbivore. This study investigated the photosynthetic capacity of bud galls induced by the wasp, Trichilogaster acaciae longifoliae (Pteromalidae) in the invasive Acacia longifolia. The role of this photosynthetic activity was examined in terms of its ability to subsidise carbon budgets, as well as to provide O₂ to the larvae and consume CO₂ in the dense gall tissue, thereby maintaining O₂ and CO₂ concentrations within the range of larval tolerance. Galls were found to contain an overall chlorophyll concentration that was less than half that of subtending phyllodes and a maximum stomata! conductance only 16% that of phyllodes. Gas exchange measurements indicated that while photosynthesis never fully compensated for the respiratory costs of the galls, light-induced carboxylation within galls contributed substantially to the maintenance and growth of galls, especially in the early stages of their development. Very low levels of O₂ were found within the larval chamber and internal tissues of galls, and these levels responded only marginally, if at all, to light, suggesting that the photosynthetic activity of galls does not play a critical role in providing 0 2 to the larvae. The percentage mortality and metabolic response of larvae in reaction to various atmospheres of reduced O₂ and elevated CO₂ indicated that larvae were tolerant of hypoxia and capable of rapidly reducing their respiratory rates to cope with hypercarbia, at least over the short term. Sustained metabolic arrest may, however, have toxic consequences for insects, causing cell damage or even death. The photosynthetic activity of galls substantially reduced internal CO₂ concentrations, thus preventing CO₂ from accumulating within galls over prolonged periods. Hence, the capacity of galls to photosynthesise has significant implications for the survival of the developing larvae by reducing the risk of hypercarbic_toxicity and supplying additional carbohydrates to the gall and its inhabitants, thereby creating a favourable microhabitat in which to live.
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Henning, Jessica. "The physiological effects of Trichilogaster acaciaelongifoliae on Acacia longifolia." Thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/26657.

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39

Mutiti, Christine Mango. "Landscape Structure of Acacia-Commiphora Bushland in Southeastern Kenya." Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1280206409.

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40

Finger, Cesar Augusto Guimarães. "Distribuição de diâmetros em Acácia negra Acácia mearnsii de Wild, em diferentes povoamentos e idades." reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/24764.

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O presente trabalho teve como objetivos estudar a distribuição diamétrica de acácia negra em povoamentos independentes, selecionar a equação que melhor descrevesse as distribuições e estudar as variações das distribuições em diferentes idades. Os dados provem da Fazenda Dona Bernarda, de propriedade da TANAC S.A. em Montenegro, Rio Grande do Sul (nas coordenadas geográficas de 30° de latitude sul e 52° de longitude oeste e clima do tipo Cfa , subtropical , segundo Köeppen). Foram estudados os diâmetros quanto a distribuição e estabilidade em relação a curva normal nas idades de 3,5 a 7,5 anos , através do pacote de computação MLESD - Maximun Likelihood Estimation for Selected Distributions. As distribuições testadas foram Normal, Log-normal, Gama, Weibull, SB e Beta. Estas foram ajustadas pelo método de Máxima Probabilidade e selecionadas pelo critério do Logarítmo da Probabilidade e Kolmogorov-Smirnov. A distribuição SB foi a selecionada para descrever os dados de diâmetros nas cinco idades estudadas. No entanto, a distribuição Beta nas idades de 3,5 , 5,5 , e 7,5 e a Weibull na idade de 3,5 anos, também podem ser utilizadas, porém, com ajustes um pouco inferiores que os proporcionados pela distribuição SB. As equações Normal, Log-normal e Gama não ofereceram bons ajustes em nenhuma das idades estudadas, sendo desaconselháveis as suas utilizações para descrever a distribuição de diâmetros de acácia negra.
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Sprent, JI, DW Odee, and FD Dakora. "African legumes: a vital but under-utilized resource." Oxford University Press, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001196.

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Abstract Although nodulated legumes have been used by indigenous peoples in Africa for centuries, their full potential has never been realized. With modern technology there is scope for rapid improvement of both plant and microbial germplasm. This review gives examples of some recent developments in the form of case studies; these range from multipurpose human food crops, such as cowpea (Vigna unguiculata (L.) Walp.), through to beverages (teas) that are also income-generating such as rooibos (Aspalathus linearis (Burm. f.) R. Dahlgren, honeybush (Cyclopia Vent. spp.), and the widely used food additive gum arabic (Acacia senegal (L.) Willd.). These and other potential crops are welladapted to the many different soil and climatic conditions of Africa, in particular, drought and low nutrients. All can nodulate and fix nitrogen, with varying degrees of effectiveness and using a range of bacterial symbionts. The further development of these and other species is essential, not only for African use, but also to retain the agricultural diversity that is essential for a changing world that is being increasingly dominated by a few crops such as soybean.
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Jibo, Abdullahi Umar. "Variation in drought tolerance and morphological plasticity among two provenances of Acacia senegal (Senegalia senegal) seedling in North Eastern Nigeria." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=227119.

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43

Gaol, Mangadas Lumban. "Ecological study of plant species at Sandford Rocks Nature Reserve (SRNR)." Curtin University of Technology, Department of Environmental Biology, 2002. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=13955.

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The ecology of plant species at Sandford Rocks Nature Reserve (SRNR) was studied. The study site is an important nature reserve that contains relatively undisturbed natural vegetation. It has a mosaic of exposed granite rocks, scrublands and woodlands. The study involved: a description of the structure and composition of the vegetation; the population characteristics of selected Acacia species; aspects of reproduction in Acacia; germination and seedling characteristics of some Acacia and grass species that dominate the reserve; the effect of seed size on germination and seedling characteristics; and, the relationship of seed size to seed coat thickness in selected Acacia species. Five different areas were studied using the point centered quarter method to sample the woody perennial species. Thirteen Acacia species were examined for reproduction characteristics; and in 2 selected Acacia species, the effects of phyllode and/or inflorescence removal on reproduction was investigated. Germination tests were conducted to identify germination characteristics in 8 Acacia and 7 grass species dominant at SRNR. The possible effects of variation in seed size on germination; seedling characteristics; and, seed coat thickness were investigated in Acacia fauntleroyi and Acacia prainii. A total of 85 species from 20 families of woody perennials were collated. All areas were dominated by the Myrtaceae, Mimosaceae and Proteaceae families. There was considerable variability in the structure and composition of vegetation. Most species were present in particular sites and the composition of communities appears to be related to the heterogeneity of the habitat within the reserve. In areas of shallow or rocky soil, vegetation types present include Allocasuarina huegeliana woodland, Grevillea paradoxa low scrubland and Acacia neurophylla medium shrubland.
In a seasonally wet area, vegetation types present include low open grassland; Eucalyptus capillosa (wandoo) woodland; and, Acacia saligna thicket. In deep, dry sandy soil, vegetation types include Phebalium tuberculosum shrubland, Acacia acuminata and Acacia coolgardiensis thickets. On relatively flat areas that gain water from adjacent large granite hills, the vegetation consists mainly of tall, open woodlands of Eucalyptus species. Vegetation types include: medium tall Eucalyptus salmonophloia woodland with Kunzea pulchella shrubland at the periphery of the Eucalyptus woodland. At rock areas, vegetation types present include dense Leptospermum erubescens thicket, low open Acacia prainii and Dodonaea viscosa shrubland. Of the Acacia populations studied, in A. lasiocalyx no recent seedling establishment was observed. It is hypothesised that recruitment occurs in particular periods. As the plants are associated with rock and soils are generally shallow, it appears that recruitment depends on run-off water from the rocks in winter. Continuous recruitment seems to be the pattern in A. prainii with both seedlings and saplings represented. A. fauntleroyi forms relatively small populations; apparently long drought periods (>l00 d) result in mass death and limit its population size. In A. hemiteles, no seedling stage was found, root competition (for water) from associated Eucalyptus species presumably limits its recruitment. Reproductive success of Acacia is affected by rainfall. A wet winter is required to induce flowering and further rain is required after flowering to promote pod development and good seed set.
All Acacia species suffer from drought in the reproduction season, however they differ in their degree of susceptibility. Leaflessness and tree shape also affect Acacia fecundity. Plants bearing more phyllodes produce more flowers and pods, and branches in the upper part of the crown bear heavier inflorescences. In 1998, all Acacia species at SRNR produced mature seed of low weight, with many immature and diseased seed, which gave poor germination. A late spring frost in 1998 is believed to be responsible for limited seed development. In two selected Acacia species, removal of phyllodes reduced the number of pods produced. Presumably, phyllode removal reduces photosynthate produced, therefore the competition among inflorescences (or pods) for resources is more intense and subsequent abortions are likely to occur. All Acacia species studied showed best germination in the cool winter temperature range. Apparently, seeds are adapted to germinate in winter when seasonal moisture is more likely to be available. The best temperature however, varied slightly between species. The grass species dominant in the reserve, except for Aristida contorta, also had more germination in cooler rather than warmer temperatures. The flora of SRNR is similar to typical vegetation of the Southwest. Generally, Acacia species are present only in particular sites, presumably were habitat moisture allows. Seedlings of Acacia species growing in naturally dry areas have greater root: shoot masses than those growing in seasonally wet areas. Biomass partitioning is an apparent strategy to conserve water. Of the 7 grass species, Amphipogon strictus appears to have fastest growth.
Eriachne ovata has greater root than shoot mass, while in all other species, shoot mass is greater than root mass; a characteristic of species that grow well in moist habitats. The longest shoots and roots are in Austrostipa elegantissima, an understorey species of eucalypt woodland. In A. fauntleroyi, the degree of hard-seededness varies between seed sizes. There is a higher proportion of soft seed in smaller seed. Seed of different sizes show some responses to different pre-treatments and incubation temperatures for germination. Larger seeds generally germinate in greater numbers after higher treatment temperatures. The best treatment for small seeds is pre-treatment at 75°C and incubated at 15°C. For medium and large seed, best pre-treatment is at 75°C with incubation at 30°C or soaking in boiling water and incubation at either 15 or 3°C. In A. prainii, seed size; pre-treatment; incubation; and, their interaction all affected germination; larger seeds are more viable. The best treatment to promote germination of A. prainii is soaking in boiling water and incubation at 25°C. In both A. fauntleroyi and A. prainii, larger seeds produce larger seedlings. Seedlings from large seeds have the potential for more rapid pre-photosynthetic growth. Larger, heavier seed has a thicker seed coat. The seed coat of A. prainii is thicker than in A. fauntleroyi; the difference in seed coat thickness is reflected by more soft seed in A. fauntleroyi (35%) than in A. prainii (6%).
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44

Hackman, Richard Leonard. "Soil erosion and nutrient dynamics in tropical mahogany (Swietenia macrophylla) and acacia (Acacia mangium) forest plantations of the Caratal Watershed, St. Vincent, West Indies." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ38588.pdf.

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45

Oliveira, Leonardo da Silva. "Aspectos entomológicos em povoamentos homogêneos de Acacia mearnsii de Wild." Universidade Federal de Santa Maria, 2007. http://repositorio.ufsm.br/handle/1/3705.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The proposed work aimed to investigate the entomological aspects in homogeneous stands of Acacia mearnsii (black wattle). It was considered: insects identification and damage quantification on seeds; treatment effect of seeds and the insecticides application on the aerial part of plants of direct sowing; the survey qualiquantitative by light traps mean; the main species of Coleoptera present in the suppressed trees; the attack characterization of Oncideres impluviata and its influence on wood volume of black wattle. The experiments were carried out in cultivated areas of black wattle situated at the municipality of Butiá and Minas do Leão in the carboniferous region of Rio Grande do Sul during March 2004 to July 2006. It was verified that the Stator limbatus (Coleoptera: Chrysomelidae) caused expressive damage to the black wattle seeds. There was no statistical increase in relation to the use of insecticides to the directly sowing, however black wattle plants submitted to thiamethoxam application on the aerial part showed better development. Among the 11 orders collected by light traps the populations of lepidoptera, coleoptera and hemiptera were quantitatively pointed. Sigara sp. (Hemiptera: Corixidae), Conoderus alfredense (Coleoptera: Elateridae) and Plectris crassa (Coleoptera: Scarabaeidae) were the species more frequents, abundant and constants collected by the light traps. At the qualitative survey made in suppressed trees it was observed 40 species of Coleoptera distributed in ten families, focusing in Curculionidae with twelve representatives, Cerambycidae with ten and Scarabaeidae with nine species. It was verified that O. impluviata attacks the high parts of the tree, independent of age, from the borders into the stand and cuts the branches averaging 14mm of diameter and 1.4 m of length. These branches present high contents of nitrogen and phosphorus in their chemical composition when compared to non-cut branches. The attack of O. impluviata did not reduce the wood volume produced for black wattle trees.
O trabalho proposto teve como objetivo o estudo de aspectos entomológicos em povoamentos homogêneos de Acacia mearnsii (acácia-negra), considerando a identificação de insetos e quantificação de seus danos em sementes; o efeito do tratamento de sementes e a aplicação de inseticidas na parte aérea de plantas de semeadura direta; o levantamento quali-quantitativo, por meio de armadilha luminosa; as principais espécies de Coleoptera presentes em sub-bosque; a caracterização do ataque de Oncideres impluviata e a sua influência no volume de madeira de acácia-negra. Os experimentos foram realizados em áreas de plantio e povoamentos de acácia-negra situados nos municípios de Arroio dos Ratos, Butiá e Minas do Leão, na região carbonífera do Rio Grande do Sul, no período de março de 2004 a julho de 2006. Verificou-se que Stator limbatus (Coleoptera: Chrysomelidae) causa expressivos danos a sementes de acácia-negra. Não houve diferença significativa em relação ao uso de inseticidas para a semeadura direta. Das 11 ordens coletadas por meio de armadilha luminosa, destacam-se quantitativamente as populações de lepidópteros, coleópteros e hemípteros. Sigara sp. (Hemiptera: Corixidae), Conoderus alfredense (Coleoptera: Elateridae) e Plectris crassa (Coleoptera: Scarabaeidae) foram as espécies muito freqüentes, muito abundantes e constantes, coletadas através de armadilha luminosa. No levantamento qualitativo realizado em sub-bosques foram observadas 40 espécies de Coleoptera, distribuídas em dez famílias, com destaque para os Curculionidae com doze representantes, Cerambycidae com dez e Scarabaeidae com nove espécies. Constatou-se que O. impluviata ataca nas partes mais altas da árvore, independente da idade, tanto nas bordas como no interior de povoamentos. O. impluviata anela galhos com diâmetros e comprimentos médios de 1,4 cm e 1,4 m, respectivamente. Estes galhos apresentam maiores teores de nitrogênio e fósforo em sua composição química quando comparados com galhos não-anelados. O ataque de O. impluviata não reduziu o volume de madeira produzido por árvores de acácia-negra.
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46

Silva, Virginia Claudia da. "Análise dos flavonóides de Acacia longifolia (Andr.) Willd. Leguminosae-Mimosoideae." reponame:Repositório Institucional da UFPR, 2001. http://hdl.handle.net/1884/41273.

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Orientador: Vitor Alberto Kerber
Co-orientador: Obdulio Gomes Miguel
Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Saúde
Resumo: Acacia /ongifolia (Andr.) Willd., é um arbusto, de 3-4 m de altura. Arbusto originário da região leste-tropical da Austrália, muito cultivado para fixar dunas em terrenos íngremes, sujeitos a erosão. Acacia longifolia (Andr.) Willd. foi investigada visando à identificação dos flavonóides majoritários em suas flores e a avaliação de atividades antimicrobianas. Através de métodos cromatográficos, três flavonóides foram isolados a partir da fração acetato de etila. Estes foram identificados através de análises espectroscópicas e propriedades físico-químicas como uma flavanona a naringenina, e dois de seus heterosídeos, a 5-f3-0-galactosil-naringenina e 5-f3-Dglucosil- naringenina. Usando CLAE, os flavonóides isolados foram quantificados no material vegetal, apresentando teores mínimos de 0,582 % (m/m) de 5-f3-Dgalactosil- naringenina, 0,2% (mim) de 5-f3-0-glucosil-naringenina e 0,018 % (mim) de naringenina. A fração acetato de etila a uma concentração de 500 ppm, mostrou uma significativa atividade antifúngica, inibindo 30% do crescimento micelial de Rhizoctonia sp. Também houve inibição do crescimento micelial de Colletotrichum acutatum (15,9%) e de Fusarium oxysporum (10,5 %). O extrato bruto etanólico e as frações acetato de etila e diclorometano foram testadas contra as cepas de Staphy/ococcus aureus, S. epidermidis e Escherichia colí em concentrações até 1000 ?g, mas nenhuma atividade foi detectada.
Abstract: Acacia longifolia (Andr.) Willd., is a shrub, (3-4 m in height). Originally from Australia east-tropical region, it is cultivated to firm dunes in steep ground. Acacia longifolia (Andr.) Willd. was investigated to evaluating anti-microbial activities and to identify flavonoids in its flowers. Three flavonoids were isolated by chromatographics means from the ethyl acetate fraction. The flavonoids were identified by spectral analysis and physical-chemical properties given Naringenin, a flavanone and two of its glycosides, 5-13-D-galactosil-naringenin and 5-f3-D-glucosil-naringenin. Using an HPLC system, the isolated flavonoids were quantified in the plant material, giving minimal values of 0,582 % (w/w) for 5-f3-D-galactosil-naringenin, 0,2 % (w/w) for 5- 13-D-glucosil-naringenin and 0,018 % (w/w) for naringenin. At the concentration of 500 ppm the ethyl acetate fraction showed a remarkable anti-fungi activity inhibiting 30% of the micelial growing from Rhizoctonia sp .. lt also inhibit the micelial growing of Colletotrichum acutatum (15,9%) and Fusarium oxysporum (10,5%). The crude ethanolic extract, the dicloromethane and the ethyl acetate fractions were tested againt strains of Staphylococcus aureus, S. epidermidis and Escherichia coli at concentrations up to 1000 ?g giving no activity.
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47

Doktorchik, Acacia M., and University of Lethbridge Faculty of Fine Arts. "Sehnsucht and alienation in Schubert's Mignon settings / Acacia M. Doktorchik." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Music, c2011, 2011. http://hdl.handle.net/10133/3051.

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Sehnsucht (longing) and alienation were two central themes of 19th century German Romanticism in literature, music and art. Franz Schubert was one of the great masters of the Romantic era to understand and express these intense emotions through his compositions. This paper discusses Sehnsucht and alienation in Schubert’s settings of the Mignon songs from Johann Wolfgang von Goethe’s novel Wilhelm Meisters Lehjahre (Master William’s Apprenticeship). Mignon, a secondary character in this novel, is a prime example of one who experiences these emotions and whose principal medium of expressing herself is through her five songs. My thesis focuses on how Schubert portrays Mignon’s longing through use of dissonance, harmonic progressions, melodic contour and shifts in vocal register.
iv, 46 leaves ; 29 cm
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48

Prescott, Matthew. "The pollination ecology of a south-eastern Australia Acacia community." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422674.

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49

Gillespie, Trudi. "Genetic variation in salt tolerance of four African Acacia species." Thesis, Bangor University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327422.

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50

Strydom, Matthys. "A perspective on the seed bank dynamics of Acacia saligna." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20389.

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Thesis (MScConEcol)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Acacia saligna, or Port Jackson, is an Australian Acacia which has spread throughout the Western and Eastern Cape provinces of South Africa where it has become invasive and a prominent feature of the vegetation. In areas where A. saligna establishes it replaces natural vegetation, alters ecosystem processes and interferes with agricultural practices. Consequently large management efforts have been made to eradicate this invasive alien tree. However, its large and persistent soil stored seed bank, even in the presence of management and biological control agents, poses a serious obstacle to its successful removal. Furthermore the reproductive output and the size of the seed bank of A. saligna over its whole distribution as well as the variation of seed production and the seed bank with environmental conditions in time and space is poorly known. Understanding the seed bank dynamics of A. saligna in time and space is essential for reducing invasive success and achieving management objectives. This study has filled this knowledge gap through studying the seed production and seed bank of A. saligna over its invaded range in South Africa, including how environmental factors influence these factors in time and space. The seed rain of A. saligna was assessed at 10 sites across its distribution in South Africa. The seed rain of A. saligna at the sites was determined through the use of seed rain traps. Twenty five traps were placed out at every site during November 2010 (pre-dehiscence) which was collected again during April 2011 (postdehiscence). The seed bank of A. saligna was estimated through sampling at 25 sites across its distribution range in South Africa. The seed bank was sampled during April 2010 (postdehiscence), November 2010 (pre-dehiscence) and April 2011 (post-dehiscence) through taking 50 litter and soil samples at every site which gave a total sampling size of 3 750 for both the seed in the soil and litter over its distribution in South Africa. In addition the average tree diameter, tree density, average number of Uromycladium tepperianum induced galls per tree, the summer aridity index, De Martonne aridity index, winter concentration of precipitation, temperature of coldest month and the soil texture for every site was determined. The damage done by the seed feeding weevil, Melanterius compactus, was also estimated for the seed rain study sites. Water availability during the hot summer months was assessed as the most important factor governing seed production and seed bank size. Riparian and non-riparian water regimes were shown to be important in understanding the seed bank dynamics of A. saligna over its distribution range in the Cape Floristic Region. In non-riparian A. saligna populations the seed production and consequently the size of the seed bank and its rate of accumulation is limited by both water and temperature and in riparian A. saligna populations, only by temperature. Therefore, two environmental gradients influence the seed bank dynamics of Port Jackson in South Africa. In non-riparian A. saligna populations the number of seed produced and the accumulation of seed in the seed bank generally increases along the west coast of South Africa from Clanwilliam towards Cape Town and along the south coast from Cape Town towards Port Elizabeth. Seed banks are larger closer to the coast, when A. saligna populations of similar age are compared. In riparian A. saligna populations, the number of seed produced generally increases from Port Elizabeth towards Cape Town and from Cape Town towards Clanwilliam, again, with larger seed banks being accumulated closer to the coast, when populations of similar age are compared. This study provides managers with a useful tool for prioritising management efforts.
AFRIKAANSE OPSOMMING: Acacia saligna of Port Jackson is ‘n indringerplant in Suid-Afrika wat afkomstig is uit Suid-Wes Australië. Acacia saligna is ‘n onmisbare kenmerk van die plantegroei in die Wes en Oos-Kaap. Waar Port Jackson vestig, verplaas dit natuurlike plantegroei, verander dit ekosisteem prossesse en verhinder dit landbou praktyke. Gevolglik is groot bestuurspogings aangewend om hierdie indringer plant uit te roei. In die teenwoordigheid van bestuursprogramme en biologiese beheer bly A. saligna lewensvatbaar as ‘n gevolg van die plant se groot blywende grond saadreserwes. Verder is die saad produksie en saadbank grootte van A. saligna oor sy verspreiding bereike asook hoe dit met omgewingstoestande in tyd en ruimte interreageer en varieer grootendeels onbekend. ‘n Goeie en omvattende begrip van die saadbankdinamika is belangrik om die indringings vermoë van die plant te verlaag en om bestuursdoelwitte te bereik. Hierdie studie vul die bestaande gaping in die kennis aangaande die saadbank dinamika van A. saligna aan deur die saadproduksie en die saadreserves van die indringerplant oor sy verspreiding in Suid-Afrika te bestudeer, insluitend hoe omgewingstoestande die saadbankdinamika beïnvloed in tyd en ruimte. Die saadreën vir 10 A. saligna populasies was bepaal deur die gebruik van saadlokvalle. Vyf-entwintig lokvalle was uitgeplaas in elke bestudeerde Port Jackson perseel gedurende November 2010 (voor-saadval) wat weer gaan haal is gedurende April 2011 (na-saadval). Die saadbank van A. saligna was bepaal in 25 populasies van die boom gedurende April 2010 (na-saadval), November 2010 (voor-saadval) en April 2011 (na-saadval) deur die neem van 50 blaar- en grondmonsters by elke perseel wat ‘n totaal van 3 750 blaar- en grondmonster gee oor die hele verspreiding van A. saligna in Suid-Afrika. Verder is die gemiddelde boomdeursnee, boomdigtheid, gemiddelde Uromycladium tepperianum geinduseerde galle per boom, die somers droogtheids indeks, De Martonnes droogtheids indeks, die winter konsentrasie van presipitasie, die temperatuur van die koudste maand en die grond tekstuur van elke Port Jackson stand bepaal. Die skade wat die saad voedende kewer, Melanterius compactus, aanrig aan die sade van A. saligna is ook vir die persele waar die saadreën eksperiment uitgevoer is, bepaal. Die beskikbaarheid van water vir A. saligna in die droë somermaande is bepaal as die belangrikste faktor wat die grootte van die saadproduksie en saadbank beïnvloed. Oewer en nie-oewer water omgewings is bevind as noodsaaklik om die saadbank dinamika van A. saligna oor die indringerplant se verspreidingareas in die Kaap Floristiese Streek te verstaan. In nie-oewer A. saligna populasies word saadproduksie en gevolglik die grootte en tempo van akkumulasie van die saadbank deur beide water en temperatuur omstandighede beperk, terwyl in oewer A. saligna populasies word die indringerplant slegs deur temperatuur omstandighede beperk. Gevolglik blyk dit dat twee water beskikbaarheids gradiënte bestaan waarop die plant reageer wat dan uitgedruk word in die plant se saad produksie en gevolglik ook die plant se saadbank. In nie-oewer Port Jackson populasies neem die saadproduksie en die tempo waarteen die saadbank akkumuleer algemeen toe langs die weskus van Clanwilliam na Kaapstad en van Kaapstad na Port Elizabeth, met grootter saadproduksie en saadbank akkumulasie nader aan die kusgebiede, wanneer A. saligna populasies van dieselfde ouderdom vergelyk word. In oewer Port Jackson populasies neem die saadproduksie en die tempo waarteen die saadbank akkumuleer algemeen toe van Port Elizabeth na Kaapstad en van Kaapstad na Clanwilliam, met grootter saadproduksie en saadbank akkumulasie nader aan die kusgebiede, wanneer A. saligna populasies van dieselfde ouderdom vergelyk word. Hierdie studie verskaf bestuursplanne met ‘n nuttige raamwerk waarvolgens uitroeiing en beheer programme vir A. saligna beplan kan word.
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