Typescript. Includes bibliographical references (leaves [279]-287) This thesis examines the growth ring structure of Eucalyptus camaldulensis Dehnhardt and investigates links between ring features and the climatic conditions under which growth took place. Samples of E. camaldulensis from the Barmah Forest (near the River Murray in northern Victoria) were used in the study. E. camaldulensis growth is linked to periodic flooding, and the Barmah Forest contains sites that are frequently flooded. Wood samples were obtained from sites subject to different average flooding frequencies. Trees used in the study grew out of natural regeneration in the 1920's and 1930's and from regeneration trials in the early 1960's. Initial investigation of E. camaldulensis samples revealed ring-like features that were able to be traced on samples by eye. Microscopic investigation showed that there existed considerable variations in the properties of individual rings at different positions on the samples, and that the boundaries between rings were often indistinct. Further examination of E. camaldulensis microstructure was performed on samples from two trees that grew on sites with significantly different flooding regimes. These samples possessed features that formed rings, with rings being successfully matched between samples taken from different heights in the trees. As the complex microstructure of E. camaldulensis did not lend itself to standard dendroclimatological techniques, methods were developed to facilitate the comparison and matching of rings. These methods were also used in the successful matching of ring patterns with the output from a simple climate-based tree growth model. Two sets of E. camaldulensis samples (BS1, with 33 samples, and BS2, with 39 samples) were studied to assess the level of individual variability in ring patterns, and to provide a representative ring pattern for climate comparison. Following the development of methods for identifying samples with similar ring patterns, a subset of similar samples was selected from the BS1 set. A member of this subset was selected to provide a ring-width pattern upon which a representative pattern of ring features for BS1 was based. The rings of the BS2 samples possessed poorer ring definition than the BS1 samples and provided no new or different information. Consequently, the representative ring pattern for BS1 was used in a dendroclimatological investigation for the site. The ring pattern was matched with the output from two tree growth event models. Although rings were matched with growth events over a 27 year period, the high variability of individual ring features prevented matching of particular types of ring features with particular types of climatic events. An investigation of numerical methods for matching ring patterns with ring or growth event patterns, and for identifying samples with similar ring patterns, was performed using signal smoothing and filtering techniques and a dynamic time-warping procedure. Ring matching and identification of similar ring patterns was found to be most successful on samples where the ring patterns, expressed as continuous signals, had similar mean and amplitude values. The techniques were unsuccessful in the matching of signals of different form, such as continuous ring pattern signals and discontinuous growth event signals.

Attempts were made to grow Fergusobia nematodes in a dual aseptic culture with Eucalyptus camaldulensis. Callus tissue was grown from E. camaldulensis stem pieces in aseptic conditions. Calli were prone to deterioration after 14 days unless transferred to fresh growth medium. Lower levels of solutes (25% Murashige and Skoog salts, 25% plant vitamins and 0.5% sucrose) were more successful than published concentrations. Fergusobia J2 nematodes were surface sterilised with either Hibitane or washed with water to prepare them for inoculation of callus (Hay, 1994). Fergusobia subsequently recovered from plates of callus were all dead, which raised questions of how the nematodes are suited to Murashige and Skoog salt solutions. The survival of Fergusobia in aqueous solutions was then observed. It has been assumed that Fergusobia live about 2 days after dissection. Amphimictic nematodes from E. camaldulensis axial bud galls were used for a survival study. Nematodes lived for as long as 12 days in fresh tap water and 11 days in 1% M.S. solution. They were more active in tap water than in 1% M.S. solution. Nematodes in a dish together with dissected gall material died within 2 days. Nematodes in a separate dish with fresh tap water and clean gall fibres were observed to gather around the fibres. Observations of Fergusobia could be made within fresh solutions providing deteriorating gall tissues were removed from the dish. Gall production was attempted on E. camaldulensis grown in the glasshouse. These tree saplings were pruned to encourage new growth and periodically treated for infestations of scale insects leading to growth of sooty mould. Two forms of cage construction were used: (1) 1 m ³ screened cages and (2) acetate sleeves as used by Goolsby et al., 2000. Within the 1 m ³ cages containing flies, the growing points on saplings were blackened, possibly due to over-exploitation by ovipositing flies. One growing point caged in an acetate sleeve showed oviposition scars but did not produce a mature gall. Production of galls in the glasshouse was hindered by a lack in coincidence of flies emerging from mature galls and the flush of new growth following pruning. The production of galls within the glasshouse was not achieved. The phenology of E. camaldulensis, a host for the Fergusonina/Fergusobia mutualism, and gall ecology were observed in a two-year, non-destructive, field study in the Urrbrae Wetlands, Adelaide, South Australia. Tree growth and gall development was observed in the lower regions (0 – 2 m) of young trees. Three bud forms, terminal leaf bud, axial leaf bud and flower bud galls were monitored on the trees. The densities of galls were highly seasonal. Greatest density of growing points, axial leaf bud and flower bud galls occurred mostly during mid-winter to spring, whereas that of terminal leaf bud galls occurred during mid-spring to summer. Galling of flower buds did not appear to influence flowering and more flower buds and flowers occurred in the second year of the study as the trees matured. Trees mostly had medium (30-70%) levels of leaf damage, but there were seasonal trends in damage levels. Low scores for leaf damage were associated with increases in flower bud and flower production. Leaf damage, including sooty mould, appeared to increase during the cooler winter months. There were no significant seasonal relationships between levels of leaf damage and either growing point density or the occurrence of galls. When trees were compared with each other, those with lower leaf damage were more likely to have more growing points. The appearance of the canopy and the likelihood of a tree to have galls varied greatly between the trees. One tree was particularly susceptible to leaf attack, rarely had new leaves and produced no mature galls during the study. The colouring of leaves varied between trees, which indicates possible genetic variations causing some trees to be more likely hosts for Fergusonina/Fergusobia. Both new vegetative growth and terminal leaf bud galls were concentrated on the northern and eastern quadrants. Axial leaf bud and flower bud galls occurred more on the western or southern quadrants where they were possibly more protected from sun exposure on the northern or eastern quadrants. Axial galls on the northern side of one tree became reddened while those in the southern and western quadrants remained green. Reddening of axial galls may increase their likelihood of parasitism and predation by birds. Each of the three gall forms occurred within certain positions in the canopy. The tree host resource is partitioned effectively, with the three gall forms occurring on three different host structures. Additionally, the two vegetative forms terminal leaf bud and axial leaf bud galls occur on different shoot regions and in different seasons. The numbers of the galls is probably also affected by biotic and climatic influences. Parasitism, plant canopy shading, nutrient levels and host genetics are possible influences. Assuming an interval of 4 weeks between oviposition and first observation within the current study, terminal leaf bud galls had an average longevity of 11 weeks and axial leaf bud galls an average longevity of 14 weeks. Flower bud galls had longevities of 14 to 27 weeks from oviposition to senescence, assuming an interval of 6 weeks between oviposition and first observation within the current study. Flowers and flower buds occur irregularly within the eucalypts so it would be advantageous for flies and nematodes developing within flower bud galls to have extended or variable longevities to allow fly emergences to coincide with new flower buds. Not all of the galls recorded matured to produce adult flies. Nearly half of the terminal leaf bud galls initiated were aborted, recorded as absent, parasitised or eaten (45% of initiated galls). Of the three gall forms, they were the most prone to obvious parasitism and as many as 12 hymenopteran species have been reared from terminal leaf bud galls on E. camaldulensis (Taylor et al., 1996). These galls obviously provide a resource for many species within multiple trophic levels. Fourteen percent of axial leaf bud galls were absent or eaten and birds were seen breaking off and feeding on the galls. More than half (55%) of the initiated flower bud galls disappeared during the period of observation, possibly due to the foraging of birds. Destructive sampling and rearing out of parasitoids from both axial leaf bud and flower bud gall forms is needed to establish what species exist within them. Terminal leaf bud galls ranged from 7.5 to 30.1 mm in diameter and 10.0 to 43.6 mm in length. Flower bud gall size varied, with the largest being 15.0 mm by 22.3 mm. Axial leaf bud galls, ranged from 2.6 to 13.0 mm in diameter and length ranged from 2.3 to 10.5 mm. The larger axial leaf bud galls were nodular and appeared to have multiple locules. Destructive sampling and rearing out of flies is needed to establish the relationship between size and numbers of flies emerging. Terminal leaf bud galls increased in size, including many locules and exit holes per gall. Axial leaf bud galls were much smaller than the terminal leaf bud galls and 99% had only one to three exit holes. The rounded shape and presence of few locules within the axial leaf bud galls indicate that this form is limited to a shape and size producing few flies. The observation of greater size of terminal leaf bud galls suggests that these galls may have multiple foundresses. Twelve of the 13 flower bud galls with exit holes had either one or two holes. In flower bud galls on E. camaldulensis. the operculum remains sealed and the characteristic Fergusonina “window” appears at the side of the flower bud before fly emergence through a single hole. Destructive sampling is also necessary to determine parasitism of each of the gall forms. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1331016 / Thesis (M.Sc.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

Orientador: Rafael Montanari / Resumo: A utilização de áreas de florestas nativas na região do Cerrado, convertidas para a produção agrícola e florestal, tem provocado efeitos sobre a qualidade física dos solos (QFS). Assim, o objetivo do trabalho foi avaliar a influência da ocupação de espécies florestais em comparação com uma área de Mata Ciliar (Reflorestada), implantados há 30 anos, sobre a qualidade física de um Latossolo Vermelho, na região do Cerrado brasileiro. A pesquisa foi desenvolvida no município de Selvíria-MS, durante o ano agrícola de 2016/17. Os tratamentos corresponderam a três áreas (Eucalyptus camaldulensis, Pinus caribaea var. hondurensis e Mata Ciliar reflorestada). O delineamento experimental foi o inteiramente casualizado, com três tratamentos, e vinte e cinco repetições. A QFS foi avaliada em quatro profundidades (0,00-0,10; 0,10-0,20; 0,20-0,30 e 0,30-0,40 m), utilizando dez atributos físicos do solo: macroporosidade (Ma), microporosidade (Mi), porosidade total calculada (PTc), porosidade total determinada (PTd), densidade no solo (DS), densidade da partícula (DP), resistência mecânica à penetração (RP), umidade gravimétrica (UG), umidade volumétrica (UV) e a granulometria do solo (areia, silte e argila). Os tratamentos influenciaram à QFS, alterando a DS, Mi, Ma, UG, RP e UV. A área de Eucalyptus Camaldulensis foi a que apresentou a melhor QFS, em comparação com a Mata Ciliar. / Abstract: The use of native forest areas in the Cerrado region, converted to agricultural and forestry production, has had effects on the physical quality of soils (SPQ). Thus, the objective of this work was to evaluate the influence of the occupation of forest species in comparison with an area of Ciliary Forest (reforested), implanted 30 years ago, on the physical quality of a Oxisol, in a low Cerrado region. The experiment was carried out in the municipality of Selvíria, Mato Grosso do Sul State, Brazil, during the agricultural year 2016/17. The treatments corresponded to three areas (Eucalyptus camaldulensis, Pinus caribaea var. Hondurensis and Reforested ciliary forest). The experimental design was a completely randomized design with three treatments and twenty five replicates. The SPQ was evaluated at four depths (0.00-0.10, 0.10-0.20, 0.20-0.30 and 0.30-0.40 m) using ten soil physical attributes: soil attributes analyzed were: macroporosity (Ma), microporosity (Mi), calculated total porosity (PTc), determined total porosity (PTd), bulk density (BD), real particle (RP), mechanical resistance to penetration (PR), gravimetric moisture (GM), volumetric moisture (VM) and soil grading (sand, silt and clay). The treatments influenced SPQ by altering BD, Mi, Ma, GM, RP and VM. The area of Eucalyptus Camaldulensis was the one that presented the best SPQ, compared to the Ciliary Forest. / Mestre

Submitted by Diego dos Santos (diegol_360@hotmail.com) on 2018-03-26T16:45:51Z No. of bitstreams: 1 pereira_ds_ilha.pdf: 1623527 bytes, checksum: e9e8ac0755573086604640971c171fe4 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-03-26T16:57:01Z (GMT) No. of bitstreams: 1 pereira_ds_me_ilha.pdf: 1623527 bytes, checksum: e9e8ac0755573086604640971c171fe4 (MD5) / Made available in DSpace on 2018-03-26T16:57:01Z (GMT). No. of bitstreams: 1 pereira_ds_me_ilha.pdf: 1623527 bytes, checksum: e9e8ac0755573086604640971c171fe4 (MD5) Previous issue date: 2018-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A utilização de áreas de florestas nativas na região do Cerrado, convertidas para a produção agrícola e florestal, tem provocado efeitos sobre a qualidade física dos solos (QFS). Assim, o objetivo do trabalho foi avaliar a influência da ocupação de espécies florestais em comparação com uma área de Mata Ciliar (Reflorestada), implantados há 30 anos, sobre a qualidade física de um Latossolo Vermelho, na região do Cerrado brasileiro. A pesquisa foi desenvolvida no município de Selvíria-MS, durante o ano agrícola de 2016/17. Os tratamentos corresponderam a três áreas (Eucalyptus camaldulensis, Pinus caribaea var. hondurensis e Mata Ciliar reflorestada). O delineamento experimental foi o inteiramente casualizado, com três tratamentos, e vinte e cinco repetições. A QFS foi avaliada em quatro profundidades (0,00-0,10; 0,10-0,20; 0,20-0,30 e 0,30-0,40 m), utilizando dez atributos físicos do solo: macroporosidade (Ma), microporosidade (Mi), porosidade total calculada (PTc), porosidade total determinada (PTd), densidade no solo (DS), densidade da partícula (DP), resistência mecânica à penetração (RP), umidade gravimétrica (UG), umidade volumétrica (UV) e a granulometria do solo (areia, silte e argila). Os tratamentos influenciaram à QFS, alterando a DS, Mi, Ma, UG, RP e UV. A área de Eucalyptus Camaldulensis foi a que apresentou a melhor QFS, em comparação com a Mata Ciliar. / The use of native forest areas in the Cerrado region, converted to agricultural and forestry production, has had effects on the physical quality of soils (SPQ). Thus, the objective of this work was to evaluate the influence of the occupation of forest species in comparison with an area of Ciliary Forest (reforested), implanted 30 years ago, on the physical quality of a Oxisol, in a low Cerrado region. The experiment was carried out in the municipality of Selvíria, Mato Grosso do Sul State, Brazil, during the agricultural year 2016/17. The treatments corresponded to three areas (Eucalyptus camaldulensis, Pinus caribaea var. Hondurensis and Reforested ciliary forest). The experimental design was a completely randomized design with three treatments and twenty five replicates. The SPQ was evaluated at four depths (0.00-0.10, 0.10-0.20, 0.20-0.30 and 0.30-0.40 m) using ten soil physical attributes: soil attributes analyzed were: macroporosity (Ma), microporosity (Mi), calculated total porosity (PTc), determined total porosity (PTd), bulk density (BD), real particle (RP), mechanical resistance to penetration (PR), gravimetric moisture (GM), volumetric moisture (VM) and soil grading (sand, silt and clay). The treatments influenced SPQ by altering BD, Mi, Ma, GM, RP and VM. The area of Eucalyptus Camaldulensis was the one that presented the best SPQ, compared to the Ciliary Forest.

Orientador: Marco Aurelio Cremasco / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-06T05:49:19Z (GMT). No. of bitstreams: 1 Mochi_VanessaTrevizan_M.pdf: 11350571 bytes, checksum: 3b6c20cdbe39de1c456c3bc30a129339 (MD5) Previous issue date: 2005 / Resumo: A secagem das folhas de Eucalyptus camaldulensis, cujo óleo essencial apresenta como componente principal o 1,8-cineol, é o enfoque da presente dissertação. O 1,8-cineol, conhecido também como cineol e eucaliptol, pode ser utilizado, por exemplo, no tratamento de doenças das vias respiratórias. Este estudo objetiva analisar experimentalmente a influência da temperatura do ar de secagem no rendimento do óleo essencial de Eucalyptus camaldulensis e no teor de 1,8- cineol nele presente, uma vez que o processo de secagem de plantas aromáticas auxilia na conservação das características originais por um tempo maior e aumenta o rendimento do óleo essencial quando comparado com a extração realizada com a folha úmida ou até mesmo com a folha seca naturalmente. O procedimento experimental consiste da secagem das folhas de E. camaldulensis em um secador tipo leito fixo, seguida da extração do óleo essencial em um destilador tipo Clevenger e, por fim, da análise por cromatografia gasosa para determinar e quantificar o 1,8-cineol no óleo essencial. Durante os ensaios experimentais de secagem, os seguintes parâmetros operacionais foram fixados: velocidade do ar de secagem a 0,60 m/s, carga de folhas úmidas em 100 g e tempo de secagem de 60 minutos. Foram efetuados 16 experimentos, utilizando-se temperaturas do ar de secagem entre 35 e 70 ºC. Com o estudo, foi possível verificar que o rendimento em óleo essencial extraído de folhas de Eucalyptus camaldulensis aumenta com a elevação da temperatura do ar de secagem. O mesmo pode ser observado para o teor do 1,8-cineol presente no óleo essencial. Finalmente, concluiu-se que, dentre as temperaturas do ar de secagem estudadas, 65º C foi a que forneceu melhores resultados / Abstract: The drying of leaves of Eucalyptus camaldulensis, whose essential oil presents 1,8-cineol as main component, is the subject of this work. The 1,8-cineol, also known as cineol and eucaliptol, can be used, for example, in the treatment of respiratory diseases. The objective of this study is to analyze experimentally the influence of the drying air temperature on the Eucalyptus camaldulensis outcome of essential oil and the content of 1,8-cineol. To dry aromatic plants results in the conservation of the original characteristics for a bigger period of time and also increases the outcome of the essential oil, compared to the extraction carried out with moist leaves or even with naturally dried leaves. The experimental procedure consists of drying leaves of E. camaldulensis in a fixed-bed dryer, followed by the extraction of the essential oil in a Clevenger type distiller and, finally, of the analysis by gaseous chromatography in order to determine and quantify 1,8- cineol content in the essential oil. During the drying experiments, the following operational parameters have been fixed: drying air speed of 0.60 m/s, load of moist leaves as 100 g and drying time of 60 minutes. Sixteen experiments have been carried out, with drying air temperatures comprised between 35 and 70º C. With the study, it was possible to verify that the outcome of essential oil extracted from Eucalyptus camaldulensis leaves increases with the increasing drying air temperature. The same can be observed for the content of 1,8-cineol present in the essential oil. Finally, one concluded that, among the drying air temperatures studied, 65º C offered the best results / Mestrado / Engenharia de Processos / Mestre em Engenharia Química

Eastern African countries have been confronted with forest landscape degradation and the consequently growing gap between the supply and demand of wood products. Small-scale farmers growing trees on farm have been increasingly acknowledged as a major wood supplier. Value chain analysis studies pointed out the challenges faced by the smallholders, as they are commonly engaged in informal wood markets, associated with weaker bargaining power and market asymmetry. From the Social and Solidarity Economy lens, collective action approaches through farmers’ organizations can counter the challenges of individual smallholders, while facilitating the upgrading of wood value chains. Thus, the objective of this dissertation was to analyze the (potential) roles of forest farmers’ organizations (FFOs) in wood value chain upgrading, with two case studies in Ethiopia and Tanzania. Through a systematic literature review worldwide, the study first sought to provide a knowledge base for FFO research grounded on (i) the policy context within which FFOs operate, and (ii) the typology of their performance with reference to resource mobilization, commercialization of wood products and benefit sharing mechanisms. Value chain analyses of wood products from smallholders each in Ethiopia and Tanzania were the point of departure for the empirical work, consequently treated as the case studies. A collective of smallholders and individual smallholders were embedded as the units of analysis in the two independent case studies. The two-country study setting permitted the analytical generalization of collective action approaches to value chain upgrading and the development of a research agenda and policy recommendations. Grounded on the value chain upgrading approach, FFO business models were co-developed to assess the interlinkages between the business model and (i) the organizational governance and (ii) the implications on wood value chain upgrading. Participatory workshops with existing farmers’ organizations were conducted to co-develop the business models, while focus group discussions and key informant interviews served to frame and triangulate the contextual conditions. Semi-structured household interviews were employed to examine the perception of FFOs and the main factors influencing farmers’ willingness to participate. Binary logistic regression analysis and descriptive statistics were employed in tandem with thematic analysis to analyze the data. The global review represented 57 FFOs distributed globally across 20 countries, which were manifested as associations, cooperatives, and small- and medium-sized enterprises. Research in FFOs has gained scholarly traction in the last three decades, emphasizing the emerging trend of smallholders managing forest farm forestry plots across the tropics. The review revealed three categories of FFOs, depending on the extent of the organization’s product portfolio, the value addition captured at the organizational level, and the linkages to market channels. The empirical findings revealed that southern Ethiopia and southern Tanzania had contrasting regulatory framework for the establishment of FFOs. Given the existing foreign donor program targeted at smallholders in Tanzania, institutional and financial start-up support exist. In both cases, farmers were able to envisage an FFO business model that would allow product and process upgrading of wood value chains. The FFO was perceived differently across the two cases. The Ethiopian case study referred to it as a tree marketing cooperative, which shall facilitate the production of members’ woodlots and the commercialization of wood products of members and non-members alike at a timber yard in a nearby urban area. The Tanzanian case study termed it as a tree growers’ association, which shall facilitate the production of members’ wood and non-wood products, and the commercialization of members’ sawn timber to existing traders. Achieving functional upgrading would necessitate concerted efforts by various governmental and non-governmental stakeholders. The household interviews revealed that 74% (n = 185) and 90% (n = 190) of smallholders would be willing to participate in an FFO in the Ethiopian and Tanzanian case, respectively. In Ethiopia, farmers perceived it as a collective wood marketing enterprise. A relatively small group size with substantial monetary contribution characterize farmers’ preferences to undertake a joint business on wood marketing. In Tanzania, the perception of a tree growers’ association centered on social learning elements to improve wood production and find alternative buyers, while regulating fire incidences. In both cases, the significant factors influencing farmers’ willingness to participate were (1) household socio-economic characteristics, e.g. household head’s age group or household size; and (2) experiences with tree growing activities, e.g. price satisfaction in the last sales or difficulty in market access. The synthesis permitted the derivation of the following conceptual assertion: that FFOs have the potential in upgrading the wood value chains, as long as farmers can envision a business model of an FFO that accommodates the factors influencing farmers’ willingness to participate. Overall, the study demonstrates the changing narratives of farmers’ organizations in the study countries and contributes to the commons-cooperative alliance theory – the integration of collective action and cooperative management. Furthermore, the key findings provide the groundwork to springboard future research avenues, specifically to test the derived assumptions, and recommendations for policy and development. / Die ostafrikanischen Länder sind mit der Degradierung der Waldlandschaft und der daraus resultierenden wachsenden Kluft zwischen Angebot und Nachfrage nach Holzprodukten konfrontiert. Kleinbauern, die auf ihren Höfen Bäume anbauen, werden zunehmend als wichtige Holzlieferanten anerkannt. In Studien zur Analyse von Wertschöpfungsketten wurde auf die Herausforderungen hingewiesen, mit denen die Kleinbauern konfrontiert sind, da sie in der Regel auf informellen Holzmärkten tätig sind, die mit einer schwächeren Verhandlungsposition und Marktasymmetrie verbunden sind. Aus der Sicht der Sozial- und Solidarökonomie können kollektive Handlungsansätze durch Bauernorganisationen den Herausforderungen einzelner Kleinbauern begegnen und gleichzeitig die Aufwertung von Holzwertschöpfungsketten erleichtern. Ziel dieser Dissertation war es daher, die (potenzielle) Rolle von Waldbauernorganisationen (FFOs) bei der Aufwertung von Holzwertschöpfungsketten anhand von zwei Fallstudien in Äthiopien und Tansania zu analysieren. Durch eine systematische weltweite Literaturrecherche versuchte die Studie zunächst eine Wissensbasis für die FFO-Forschung zu schaffen, die sich auf (i) den politischen Kontext, in dem FFOs agieren, und (ii) die Typologie ihrer Leistungen in Bezug auf Ressourcenmobilisierung, Kommerzialisierung von Holzprodukten und Mechanismen zum Gewinnausgleich stützt. Ausgangspunkt für die empirische Arbeit waren Wertschöpfungskettenanalysen von Holzprodukten von Kleinbauern in Äthiopien und Tansania, die folglich als Fallstudien behandelt wurden. Ein Kollektiv von Kleinbauern und einzelne Kleinbauern wurden als Analyseeinheiten in die beiden unabhängigen Fallstudien eingebettet. Der Rahmen der Zwei-Länder-Studie ermöglichte die analytische Verallgemeinerung von kollektiven Handlungsansätzen zur Verbesserung der Wertschöpfungskette und die Entwicklung einer Forschungsagenda und politischer Empfehlungen. Auf der Grundlage des Ansatzes zur Aufwertung der Wertschöpfungskette wurden gemeinsam FFO-Geschäftsmodelle entwickelt, um die Zusammenhänge zwischen dem Geschäftsmodell und (i) der Organisationsführung und (ii) den Auswirkungen auf die Aufwertung der Wertschöpfungskette für Holz zu bewerten. Zur gemeinsamen Entwicklung der Geschäftsmodelle wurden partizipative Workshops mit bestehenden Bauernorganisationen durchgeführt, während Fokusgruppendiskussionen und Interviews mit Schlüsselinformanten dazu dienten, die Kontextbedingungen zu erfassen und zu triangulieren. Halbstrukturierte Haushaltsbefragungen wurden eingesetzt, um die Wahrnehmung der FFOs und die wichtigsten Faktoren, die die Bereitschaft der Landwirte zur Teilnahme beeinflussen, zu untersuchen. Zur Analyse der Daten wurden binäre logistische Regressionsanalysen und deskriptive Statistiken in Verbindung mit einer thematischen Analyse eingesetzt. Die globale Untersuchung umfasste 57 FFOs in 20 Ländern, die in Form von Verbänden, Genossenschaften sowie kleinen und mittleren Unternehmen organisiert sind. Die Forschung zu FFOs hat in den letzten drei Jahrzehnten an wissenschaftlicher Bedeutung gewonnen, wobei der aufkommende Trend zu Kleinbauern, die in den Tropen forstwirtschaftliche Flächen bewirtschaften, hervorgehoben wurde. Die Untersuchung ergab drei Kategorien von FFOs, je nach Umfang des Produktportfolios der Organisation, der Wertschöpfung auf Organisationsebene und der Anbindung an Marktkanäle. Die empirischen Ergebnisse zeigen, dass der Süden Äthiopiens und der Süden Tansanias unterschiedliche rechtliche Rahmenbedingungen für die Gründung von FFOs haben. Angesichts des bestehenden Programms ausländischer Geber, das auf Kleinbauern in Tansania abzielt, gibt es institutionelle und finanzielle Starthilfe. In beiden Fällen waren die Landwirte in der Lage, sich ein FFO-Geschäftsmodell vorzustellen, das eine Produkt- und Prozessverbesserung der Holzwertschöpfungsketten ermöglichen würde. Die FFO wurde in den beiden Fällen unterschiedlich wahrgenommen. In der äthiopischen Fallstudie wurde sie als Baumvermarktungsgenossenschaft bezeichnet, die die Produktion der Holzflächen der Mitglieder und die Vermarktung der Holzprodukte von Mitgliedern und Nichtmitgliedern auf einem Holzlagerplatz in einem nahe gelegenen städtischen Gebiet erleichtern soll. Die tansanische Fallstudie bezeichnete sie als eine Baumzüchtervereinigung, die die Produktion von Holz- und Nichtholzprodukten der Mitglieder und die Vermarktung des Schnittholzes der Mitglieder an bestehende Händler erleichtern soll. Um eine funktionale Aufwertung zu erreichen, bedarf es konzertierter Anstrengungen verschiedener staatlicher und nichtstaatlicher Akteure. Die Haushaltsbefragungen ergaben, dass 74% (n = 185) bzw. 90% (n = 190) der Kleinbauern in Äthiopien und Tansania bereit wären, sich an einer FFO zu beteiligen. In Äthiopien verstanden die Landwirte die FFO als kollektives Holzvermarktungsunternehmen. Eine relativ kleine Gruppengröße und ein erheblicher finanzieller Beitrag kennzeichnen die Präferenzen der Landwirte für ein gemeinsames Holzvermarktungsunternehmen. In Tansania konzentrierte sich die Wahrnehmung einer Baumzüchtervereinigung auf Elemente des sozialen Lernens, um die Holzproduktion zu verbessern, alternative Abnehmer zu finden und gleichzeitig das Auftreten von Bränden einzudämmen. In beiden Fällen waren die wichtigsten Faktoren, die die Bereitschaft der Landwirte zur Teilnahme beeinflussten, (1) sozioökonomische Merkmale des Haushalts, z. B. die Altersgruppe des Haushaltsvorstands oder die Haushaltsgröße, und (2) Erfahrungen mit Baumzuchtaktivitäten, z. B. die Preiszufriedenheit beim letzten Verkauf oder Schwierigkeiten beim Marktzugang. Die Synthese ermöglichte die Ableitung der folgenden konzeptionellen Behauptung: FFOs habe das Potenzial, die Wertschöpfungsketten im Holzsektor aufzuwerten, sofern sich die Landwirte ein Geschäftsmodell für ein FFO vorstellen können, das die Faktoren in Betracht zieht, die die Bereitschaft der Landwirte zur Teilnahme beeinflussen. Insgesamt zeigt die Studie die sich wandelnden Narrative von Bauernorganisationen in den Studienländern auf und leistet einen Beitrag zur Theorie der Allmende-Kooperation - der Integration von kollektivem Handeln und genossenschaftlichem Management. Darüber hinaus bilden die wichtigsten Ergebnisse die Grundlage für künftige Forschungsansätze, insbesondere für die Überprüfung der abgeleiteten Annahmen, sowie für Empfehlungen für Entscheidungsträger.

Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Invasive alien species are widely considered to be the second most significant threat to biodiversity globally following direct habitat destruction. The invasion of riparian systems worldwide by alien plants has contributed to profound changes in biodiversity and ecosystem functioning. In South Africa, river banks and river beds are amongst the most severely invaded landscapes, with the most damaging invaders, especially in the Fynbos Biome, being trees and shrubs of the Australian genera Acacia and Eucalyptus. Although large-scale management operations are underway to clear invasive trees and restore ecosystems, little is known regarding opportunities and constraints of native species recovery after alien clearing. The core aim of this thesis is to consider whether key aspects of two widely cited restoration models (successional and alternative-state models) are useful for guiding effective management of severely-invaded riparian vegetation. As a study system, I used the Berg River in the Western Cape, South Africa which is severely impacted by invasive trees, especially Eucalyptus camaldulensis. By linking the studies of constraints for restoration and opportunities for native species recovery, the aim was to provide new possibilities for restoration in riparian zones. The thesis starts by examining constraints to restoration following alien invasion, in particular allelopathy which is one of the factors that exacerbate the impacts of Eucalyptus invasion and inhibit recovery of natural vegetation after clearing. I further assess opportunities for both passive (based on the successional model) and active restoration (based on the alternative-state model) following different strategies for removing invasive trees. The aim is to determine the effectiveness of the different models for sustainable, goal-directed management. Finally, I investigate soil-related properties namely water repellency, soil moisture and infiltration that benefit from alien clearing and subsequent recovery of native vegetation. Work on allelopathy as a restoration constrain showed that the presence of E. camaldulensis along the Berg River negatively affects the recovery of native species. Eucalyptus camaldulensis is allelopathic and induces soil water repellency. I recommend the removal of E. camaldulensis from riparian systems as this has the potential to restore soils to a non-allelopathic and non-repellent state that can pave way for native vegetation recovery. Native vegetation recovery showed mixed results. Restoration based on the successional model was generally efficient, whereas restoration based on tenets of the alternative-state model was inefficient mainly due to the several constraints active restoration faced. Native species recovery was successful on both completely cleared and thinned sites that were treated four years ago. Cover of native trees and shrubs was higher in both completely cleared and thinned sites compared to invaded sites, indicating that both methods promote indigenous vegetation recovery and set the ecosystem on a trajectory towards recovery. To improve recovery through thinning, I propose a new four-stage process to guide management in ensuring good recovery of key native species. Numerous challenges associated with active restoration following fell & stack burning and fell & removal were observed on sites that were treated one year ago. Germination of introduced native species was low in both fell & removal and fell & stack burning sites. Secondary invasion of alien herbs and graminoids, dry summer conditions and low seed germination hindered early native species establishment and recovery. Therefore, for active restoration to achieve its goals, effective recruitment and propagation strategies need to be established. Recruitment of native species was non-existent in the sites that were not seeded; this is attributed to the dominance of alien herbaceous species and graminoids and the depletion of native species in the soil seed bank. Reduction of water repellency of soils after removal of the invasive trees is important as it has the potential to affect the success of native vegetation recovery. On sites where native vegetation was recovering well, soil water repellency ranged from moderately repellent in thinned sites to non-repellent in completely cleared sites. Therefore, successful native species recovery has the potential to improve soil-related ecosystem functions, which will possibly help towards restoring indigenous vegetation. I conclude that the invasive alien tree E. camaldulensis negatively affects the native riparian ecosystem and that strategies to remove the species are needed. Recovery of native vegetation composition, structure and ecosystem function depends on the degree of ecosystem degradation and remaining ecosystem resilience. Besides having clear and effective restoration goals, restoration efforts should also develop realistic solutions to overcome numerous challenges and constraints, before any restoration plan is implemented. Successfully restored riparian ecosystems have potential to increase river flow and may lead to increased availability of water to agriculture, recreation, conservation and for domestic use, resulting in significant water security in South Africa. Both the successional model and the alternative-state model emphasize the need to identify restoration constraints. This study identified allelopathy as an important constrain for restoration and recommends measures to address it so as to facilitate restoration. Recovery based on the successional model was more effective than recovery based on the alternative-state model, which faced several constraints. Models of alternative-states incorporate system thresholds and feedbacks that might explain why the degraded system faced recovery challenges and remained resilient to restoration. / AFRIKAANSE OPSOMMING: Naas habitatverlies word indringer spesies as die grootste bedreiging vir biodiversiteit beskou. Die indringing van riviersisteme wêreldwyd deur uitheemse plante dra by tot groot veranderinge in die biodiversiteit en ekosisteem funksie. In Suid-Afrika, veral in die Fynbos Bioom, is rivieroewers en -beddings van die landskappe wat die meeste ingedring word, meestal deur skadelike indringers soos bome en struike van Australiese genera soos bv. Acacia en Eucalyptus. Alhoewel grootskaalse bestuursoperasies besig is om die indringers te verwyder en ekosisteme te herstel, is min bekend omtrent die geleenthede en beperkinge vir die herstel van inheemse spesies na die verwydering van indringers. Die hoofdoel van hierdie tesis is om die nut te bepaal van die sleutel faktore van twee wyd aangehaalde restorasie modelle (suksessie en alternatiewe-toestand modelle) om die effektiewe bestuur van hewig ingedringde oewers te lei. Die Berg Rivier in die Wes Kaap, Suid-Afrika, is gebruik as studie area. Die Berg Rivier is hewig geimpakteer deur indringers, veral deur Eucalyptus camaldulensis. Die doel was om nuwe geleenthede vir restorasie in rivier areas te voorsien, deur die studies oor beperkinge vir restorasie en geleenthede vir inheemse spesie herstel te verbind. Hierdie tesis begin deur die beperkinge van restorasie na indringing te ondersoek, veral allelopatie wat een van die faktore is wat die impakte van Eucalyptus indringing verhoog en die herstel van natuurlike plantegroei na verwydering van indringer inhibeer. Verder bepaal ek die geleenthede vir beide passiewe (gebaseer op die suksessie model) en aktiewe restorasie (gebaseer op die alternatiewe-toestand model) wat volg op verskillende strategieë van verwydering van indringer bome. Die doel is om die effektiwiteit van die verskillende modelle vir volhoubare, doel georiënteerde bestuur te bepaal. Laastens het ek die grond verwante eienskappe ondersoek naamlik, water terugdrywing, grondvog en infiltrasie wat voordeel trek uit indringer verwydering en die daaropvolgende herstel van inheemse plantegroei. Resultate van allelopatie as ʼn restorasie beperking het getoon dat die teenwoordigheid van E. camaldulensis langs die Berg Rivier die herstel van inheemse spesies negatief beïnvloed. Eucalyptus camaldulensis is allelopaties en gee aanleiding tot grondwater terugdrywing. Ek beveel aan die verwydering van E. camaldulensis vanuit rivier sisteme omdat dit die potensiaal het om grond na nie-allelopatiese en nie-terugdrywende toestand te herstel wat die weg kan baan vir die herstel van inheemse plante groei. Die herstel van inheemse plantegroei het gemengde resultate gewys. Restorasie gebaseer op die suksessie model was oor die algemeen meer doelmatig, teenoor restorasie gebaseer op die idee van ʼn alternatiewe-toestand model, hoofsaaklik as gevolg van verskeie beperkinge wat aktiewe restorasie in die gesig staar. Inheemse spesie herstel was suksesvol op beide die totaal indringer verwyderde en uitgedunde areas, wat vier jaar vantevore behandel is. Dekking van inheemse bome en struike was hoër in beide heeltemal skoongemaakte en uitgedunde areas wanneer die vergelyk word met ingedringde areas. Dit dui daarop dat beide metodes inheemse plantegroei herstel promoveer en die ekosisteem op ʼn baan na herstel plaas. Om herstel deur uitdunning te verbeter stel ek ʼn vier-stadium proses voor om bestuurders te lei vir goeie herstel van sleutel inheemse spesies. Verskeie uitdagings geassosieer met aktiewe restorasie wat volg op val-en-stapel brand en val-en-verwyder is geobserveer in areas wat ʼn jaar van te vore behandel is. Ontkieming van aangeplante inheemse spesies se sade was laag in beide die val-en-verwyder en die val-en-stapel brand areas. Sekondêre indringing van uitheemse kruie en graminoiede, droë somers toestande en lae saad ontkieming hinder die vroeë inheemse spesie vestiging en herstel. Dus, vir aktiewe restorasie om sy doel te bereik moet effektiewe werwing en verspreidings strategieë in plek wees. Daar was geen werwing van inheemse spesies in die areas wat nie gesaai was nie. Dit kan toegeskryf word in die dominansie van uitheemse kruie spesies and graminoiede en die uitputting van inheemse spesies in die grond saadbank. Vermindering van water terugdrywing van grond ná verwydering van indringer bome is belangrik aangesien dit die potensiaal het om die sukses van inheemse plantegroei herstel te affekteer. Die areas waar inheemse plantegroei goed herstel het, het grondwater terugdrywing gevarieer van gemiddeld afstootlik in die uitgedunde areas na nie-afstootlik in die heeltemal skoongemaakte areas. Dus, suksesvolle inheemse spesie herstel het die potensiaal om die grondverwante ekosisteem funksies te verbeter, wat moontlik sal bydra tot die herstel van inheemse plantegroei. Ek kom tot die gevolgtrekking dat die indringer boom E. camaldulensis die inheemse rivier ekosisteem negatief affekteer en dat strategieë om hierdie spesie te verwyder nodig is. Herstel van inheemse plantegroei samestelling, struktuur en ekosisteem funksie hang af van die graad van ekosisteem verval en die oorblywende ekosisteem weerstandigheid. Behalwe die verwyderings en effektiewe restorerings doelwitte, moet restorasie pogings ook realistiese oplossings vir die oorkombaarheid van verskeie uitdagings en beperkinge ontwikkel voor enige restorasie plan geïmplementeer kan word. Suksesvolle herstel van rivier ekosisteme het die potensiaal vir verhoogde rivier vloei en mag moontlik lei tot ʼn verhoogde beskikbaarheid van water vir landbou, ontspanning, natuurbewaring en vir huishoudelike gebruik, en kan dus ʼn beduidende bydrae kan lewer tot water sekuriteit in Suid Afrika. Beide die suksessie model en die alternatiewe-toestand model beklemtoon die noodsaaklikheid om restorasie beperkinge te identifiseer. Hierdie studie identifiseer allelopatie as ʼn belangrike beperking tot restorasie en maak aanbevelings om dit aan te spreek en om restorasie te fasiliteer. Herstel gebaseer op die suksessie model was meer effektief as herstel gebaseer op die alternatiewe-toestand model wat verskeie beperkings in die gesig staar. Die alternatiewe-toestand modelle inkorporeer sisteemdrumpels en terugvoer wat moontlik kan verduidelik waarom gedegradeerde sisteme herstel uitdagings getoon het en weerstandig teenoor restorasie gebly het.

Abstract not available

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2009. / Härtill 5 uppsatser.

Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / In many areas of south-eastern Australia, the clearance of temperate eucalypt woodlands for agriculture has been so extensive that only scattered remnant trees remain. The loss of habitat and increased spatial isolation of trees in paddocks is predicted to lead to a decline in plant fecundity because of disruptions to plant-pollinator interactions, which has important implications for the long-term persistence and maintenance of these populations. In order to assess the ability of paddock trees to contribute to population regeneration, this study assessed the reproductive viability and patterns of mating of paddock trees of two woodland species, Eucalyptus camaldulensis and E.leucoxylon in the Mt. Lofty Ranges, South Australia. This study revealed that paddock tree populations of E. camaldulensis and E.leucoxylon were reproductively viable and received sufficient visits by pollinators that resulted in high outcrossing rates. The results suggest that seed collected from these paddock trees are both genetically diverse and representative of adult populations. Therefore, such trees could contribute successfully to conservation strategies that sought to regenerate cleared paddocks. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292793 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007