Dissertations / Theses on the topic 'Acacia'
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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.
Full textENGLISH 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.
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/.
Full textAli, 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.
Full textDoctor of Philosophy (PhD)
Ali, Marina. "Antimicrobial metabolites from Australian Acacia." Thesis, View thesis, 1998. http://handle.uws.edu.au:8081/1959.7/216.
Full textMcDougal, 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.
Full textWidiatmoko. "Oxygen delignification process chemistry for Acacia." Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-10212006-130331/.
Full textForster, Michael Anthony Biological Earth & 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.
Full textOballa, Phanuel O. "Genetic variation within Acacia karroo Hayne." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334928.
Full textAli, Marina. "Antimicrobial metabolites from Australian Acacia : thesis /." View thesis, 1998. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030825.144902/index.html.
Full textSornsathapornkul, 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.
Full textKawamata, 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.
Full textOdei-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.
Full textAntunes, 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/.
Full textWood 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.
Grosso, Bernadette. "Contribution a l'etude phytodermologique du genre acacia." Toulouse 3, 1988. http://www.theses.fr/1988TOU30157.
Full textGrosso, Bernadette. "Contribution à l'étude phytodermologique du genre Acacia." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376140503.
Full textJasson, 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.
Full textGaol, 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.
Full textMarques, 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.
Full textThe 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.
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.
Full textEn 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
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.
Full textRaine, 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.
Full textOsman, 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.
Full textGaliana, Antoine. "La symbiose fixatrice d'azote chez acacia mangium - rhizobium." Paris 6, 1990. http://www.theses.fr/1990PA066516.
Full textSkowno, Andrew L. "The successional dynamics of Acacia nilotica (L.) savanna." Bachelor's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/25778.
Full textStaver, A. Carla. "Spatial and temporal variability in Acacia population dynamics." Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/6214.
Full textVariability 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.
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.
Full textWaldon, Hollis B. "Sonoran Desert Rhizobia Found to Nodulate Acacia constricta." University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/554231.
Full textMisran, 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.
Full textHamouda, Yasir. "Factors affecting the quality of Acacia senegal gums." Thesis, University of Chester, 2017. http://hdl.handle.net/10034/620895.
Full textWardill, 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.
Full textAvoseh, 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.
Full textAng, 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.
Full textSmythe, 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.
Full textMgidi, 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.
Full textThis 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.
Ndlovu, Joice. "The invasion ecology of Acacia pycnantha : a genetic approach." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/96559.
Full textENGLISH 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.
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.
Full textHaiden, Sarah. "Why do wasp induced galls of Acacia longifolia photosynthesise?" Bachelor's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/26375.
Full textHenning, Jessica. "The physiological effects of Trichilogaster acaciaelongifoliae on Acacia longifolia." Thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/26657.
Full textMutiti, Christine Mango. "Landscape Structure of Acacia-Commiphora Bushland in Southeastern Kenya." Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1280206409.
Full textFinger, 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.
Full textSprent, 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.
Full textJibo, 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.
Full textGaol, 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.
Full textIn 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%).
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.
Full textOliveira, 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.
Full textThe 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.
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.
Full textCo-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.
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.
Full textiv, 46 leaves ; 29 cm
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.
Full textGillespie, 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.
Full textStrydom, Matthys. "A perspective on the seed bank dynamics of Acacia saligna." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20389.
Full textENGLISH 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.