361 resultados para Acacia melanoxylon


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Purpose: To investigate the ethnomedicinal claims regarding the use of Acacia jacquemontii Benth. (Fabaceae) in fever, pain and inflammation. Methods: The methanol root bark extract (AJRBM) of the plant was used in the studies. Preliminary phytochemical screening of the extract was carried out according to established methods. Analgesic, anti-inflammatory and antipyretic activities were evaluated using acetic acid-induced writhing, carrageennan-induced rat paw edema and Brewer’s yeast-induced pyrexia models, respectively. The extract was administered at doses of 50 and 100 mg/kg. Aspirin (300 mg/kg, p.o.) was used as a reference drug in all models. Normal saline (10 mL/kg p.o.) was used as negative control. Results: Phytochemical screening results indicate the presence of cardioactive glycosides, tannins, flavonoids and saponins. In the acetic acid-induced writhing model, the methanol extract exhibited significant (p < 0.05) analgesic effect with 58.98 % reduction in writhing response at a dose of 100 mg/kg, compared with untreated control group. The extract significantly (p < 0.05) reduced carrageenan-induced edema at doses of 50 and 100 mg/kg to 36.84 and 47.36 %, respectively, after 1 h of extract administration. The extract exhibited predominantly dose-dependent antipyretic effect in Brewer’s yeast-induced pyrexia model. Maximum reduction in body temperature to 37.07 and 38.29 ºC at doses of 50 and 100 mg/kg, respectively, was observed, compared with untreated group (38.90 ºC) after 1 h, but this was not significant (p < 0.05). Conclusion: The plant extract exerts inhibitory effect on peripheral pain stimuli, edema and dosedependent anti-pyrexia, and thus justifies the ethnomedicinal use of Acacia jacquemontii Benth. in the management of pain, fever and inflammation.

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The aim of present work was to investigate the phenolic and volatile composition of cherry, acacia, and oak (from different species) wood chips. By the use of HPLC-DAD 18 different phenolic compounds were detected and quantified while for volatile composition, 33 different compounds were detected by GC-MS. In general, wood samples from oak species showed the higher number of phenolic compounds detected, while cherry wood samples showed the lowest levels. In addition, some individual phenolic compounds were detected, specifically in some wood samples, such as robinetin in acacia woods and naringenin in cherry wood. For volatile composition, cherry wood chips samples showed the lowest volatile composition followed by increasing order by acacia, French, Portuguese and American wood chip samples. Oak wood chip samples from American species showed the highest volatile content, as a result of high levels of several specific compounds (furfural, 5-methyfurfural, β-methyl-γ-octalactones, guaiacol, vanillin and siringaldehyde).

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Com o objetivo de desenvolver estratégias baseadas em princípios de baixas aplicações de insumos e rápido crescimento vegetal que visem a revegetação de um solo de restinga degradado em Saquarema - RJ, desde a produção de mudas florestais e estabelecimento das mesmas em campo, foi realizado este experimento na Embrapa Agrobiologia. Para avaliar os efeitos da inoculação com bradyrhizobium e fungos micorrízicos arbusculares em dois substratos usados para a formação de mudas de Acacia mangium Willd, no crescimento, nodulação, colonização micorrízica e teores e acúmulos de macro e micronutrientes, foi realizado um experimento em casa de vegetação na Embrapa Agrobiologia, utilizando um delineamento experimental inteiramente casualizado, em esquema fatorial completo 4 X 2 com 5 repetições.

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A interceptação da chuva pela copa das florestas tem grande relevância no ciclo biogeoquímico de nutrientes nos solos de baixa fertilidade sob florestas nativas e plantadas. Entretanto, pouco se sabe sobre as modificações na qualidade dessa água e no balanço hidrológico após a interceptação pela copa do eucalipto sob condições de plantios puros e mistos com leguminosas, no Brasil. Amostras de água de chuva (RF), de precipitação interna (TF) e de escoamento pelo tronco (SF), foram coletadas e analisadas quimicamente em plantios puros de mangium (espécie fixadora de nitrogênio atmosférico - EFN), guachapele (EFN) e eucalipto (espécie não fixadora de nitrogênio - ENFN) e consorciados com guachapele e eucalipto, em Seropédica, Rio de Janeiro. Nove coletores de escoamento pelo tronco (colocados em árvores), nove pluviômetros posicionados ao acaso nos plantios e três fora da influência deles foram utilizados no monitoramento durante 5,5 meses. A mangium direcionou 33,4% do total precipitado para o seu tronco. Uma estimativa baseada na correção da média anual precipitada na área (1.213 mm) indicou uma contribuição no aporte de nutrientes (kg ha-1) de 8,42; 0,95; 19,04; 6,74; 4,72; e 8,71 kg ha-1 dos elementos N-NH4+, P, K+, Ca+2, Mg+2 and Na+, respectivamente. A precipitação interna participou com a maior parte da contribuição, em comparação com o escoamento pelo tronco. Os maiores aportes de N-NH4+ (15,03 kg ha-1) e K+ (179,43 kg ha-1) foram observados sob as copas de guachapele em plantio puro. Elevada quantidade de Na+ denota influencia do mar próximo à área experimental. A mangium foi a espécie adaptada à competição por água. Comparativamente ao plantio puro de eucalipto, o plantio misto intensificou a lixiviação de N, Ca e Mg da copa, enquanto o de K e o P aportaram em menores quantidades nesse plantio.

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Environmental impacts caused during Australia's comparatively recent settlement by Europeans are evident. Governments (both Commonwealth and States) have been largely responsible for requiring landholders – through leasehold development conditions and taxation concessions – to conduct clearing that is now perceived as damage. Most governments are now demanding resource protection. There is a measure of bewilderment (if not resentment) among landholders because of this change. The more populous States, where most overall damage has been done (i.e. Victoria and New South Wales), provide most support for attempts to stop development in other regions where there has been less damage. Queensland, i.e. the north-eastern quarter of the continent, has been relatively slow to develop. It also holds the largest and most diverse natural environments. Tree clearing is an unavoidable element of land development, whether to access and enhance native grasses for livestock or to allow for urban developments (with exotic tree plantings). The consequences in terms of regulations are particularly complex because of the dynamic nature of vegetation. The regulatory terms used in current legislation – such as 'Endangered' and 'Of concern' – depend on legally-defined, static baselines. Regrowth and fire damage are two obvious causes of change. A less obvious aspect is succession, where ecosystems change naturally over long timeframes. In the recent past, the Queensland Government encouraged extensive tree-clearing e.g. through the State Brigalow Development Scheme (mostly 1962 to 1975) which resulted in the removal of some 97% of the wide-ranging mature forests of Acacia harpophylla. At the same time, this government controls National Parks and other reservations (occupying some 4% of the State's 1.7 million km2 area) and also holds major World Heritage Areas (such as the Great Barrier Reef and the Wet Tropics Rainforest) promulgated under Commonwealth legislation. This is a highly prescriptive approach, where the community is directed on the one hand to develop (largely through lease conditions) and on the other to avoid development (largely by unusable reserves). Another approach to development and conservation is still possible in Queensland. For this to occur, however, a more workable and equitable solution than has been employed to date is needed, especially for the remote lands of this State. This must involve resident landholders, who have the capacity (through local knowledge, infrastructure and daily presence) to undertake most costeffectively sustainable land-use management (with suitable attention to ecosystems requiring special conservation effort), that is, provided they have the necessary direction, encouragement and incentive to do so.

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A wireless sensor network system must have the ability to tolerate harsh environmental conditions and reduce communication failures. In a typical outdoor situation, the presence of wind can introduce movement in the foliage. This motion of vegetation structures causes large and rapid signal fading in the communication link and must be accounted for when deploying a wireless sensor network system in such conditions. This thesis examines the fading characteristics experienced by wireless sensor nodes due to the effect of varying wind speed in a foliage obstructed transmission path. It presents extensive measurement campaigns at two locations with the approach of a typical wireless sensor networks configuration. The significance of this research lies in the varied approaches of its different experiments, involving a variety of vegetation types, scenarios and the use of different polarisations (vertical and horizontal). Non–line of sight (NLoS) scenario conditions investigate the wind effect based on different vegetation densities including that of the Acacia tree, Dogbane tree and tall grass. Whereas the line of sight (LoS) scenario investigates the effect of wind when the grass is swaying and affecting the ground-reflected component of the signal. Vegetation type and scenarios are envisaged to simulate real life working conditions of wireless sensor network systems in outdoor foliated environments. The results from the measurements are presented in statistical models involving first and second order statistics. We found that in most of the cases, the fading amplitude could be approximated by both Lognormal and Nakagami distribution, whose m parameter was found to depend on received power fluctuations. Lognormal distribution is known as the result of slow fading characteristics due to shadowing. This study concludes that fading caused by variations in received power due to wind in wireless sensor networks systems are found to be insignificant. There is no notable difference in Nakagami m values for low, calm, and windy wind speed categories. It is also shown in the second order analysis, the duration of the deep fades are very short, 0.1 second for 10 dB attenuation below RMS level for vertical polarization and 0.01 second for 10 dB attenuation below RMS level for horizontal polarization. Another key finding is that the received signal strength for horizontal polarisation demonstrates more than 3 dB better performances than the vertical polarisation for LoS and near LoS (thin vegetation) conditions and up to 10 dB better for denser vegetation conditions.

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Bird communities were studied in two subregional areas of Cravens Peak, the Toko Plains and the Simpson-Strzelecki Dunefields, using the point counts method. A total of 42 2ha 20 minute surveys, 46 five-hundred metre radius area surveys and 170 5km drive through area surveys were conducted and observations made. Bird species were identified, counted and recorded. The data were compared in the two subregions and, as a whole, considering species groups according to land system on which the ecosystem occurs, the specific ecosystem and according to their general feeding habits (insectivore, omnivore, frugivore, granivore, nectarivore and carnivore). Species richness and species relative abundance were compared using Simpson’s Diversity Index and the data revealed that species are distributed largely on the basis of habitat. In general, areas with a greater number of vegetation strata recorded greater species diversity. Overall, the Tall Open Acacia georginae Shrubland on alluvial floodplains has a greater diversity of birds in a 2ha area (0.87, Simpson’s Index of Diversity 1-D) compared to the other survey sites.

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We ascertained villagers’ perceptions about the importance of forests for their livelihoods and health through 1,837 reliably answered interviews of mostly male respondents from 185 villages in Indonesian and Malaysian Borneo. Variation in these perceptions related to several environmental and social variables, as shown in classification and regression analyses. Overall patterns indicated that forest use and cultural values are highest among people on Borneo who live close to remaining forest, and especially among older Christian residents. Support for forest clearing depended strongly on the scale at which deforestation occurs. Deforestation for small-scale agriculture was generally considered to be positive because it directly benefits people’s welfare. Large-scale deforestation (e.g., for industrial oil palm or acacia plantations), on the other hand, appeared to be more context-dependent, with most respondents considering it to have overall negative impacts on them, but with people in some areas considering the benefits to outweigh the costs. The interviews indicated high awareness of negative environmental impacts of deforestation, with high levels of concern over higher temperatures, air pollution and loss of clean water sources. Our study is unique in its geographic and trans-national scale. Our findings enable the development of maps of forest use and perceptions that could inform land use planning at a range of scales. Incorporating perspectives such as these could significantly reduce conflict over forest resources and ultimately result in more equitable development processes.

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This project is led by scientists in conservation decision appraisal and brings together a group of experts working across the Lake Eyre Basin (LEB). The LEB covers a sixth of Australia, with an array of globally significant natural values that are threatened by invasive plants, among other things. Managers at various levels are investing in attempts to control, contain and eradicate these invasive plant species, under severe time and resources limitations. To date there has been no basin-wide assessment of which weed management strategies and locations provide the best investments for maximising outcomes for biodiversity per unit cost. Further, there has been no assessment of the extent of ecosystem intactness that may be lost without effective invasive plant species management strategies. Given that there are insufficient resources to manage all invasive plant species everywhere, this information has the potential to improve current investment decisions. Here, we provide a prioritisation of invasive plant management strategies in the LEB. Prioritisation was based on cost-effectiveness for biodiversity benefits. We identify the key invasive plant species to target to protect ecosystem intactness across the bioregions of the LEB, the level of investment required and the likely reduction in invasive species dominance gained per dollar spent on each strategy. Our focus is on strategies that are technically and socially feasible and reduce the likelihood that high impact invasive plant species will dominate native ecosystems, and therefore change their form and function. The outputs of this work are designed to help guide decision-making and further planning and investment in weed management for the Basin. Experts in weed management, policy-making, community engagement, biodiversity and natural values of the Basin, attended a workshop and agreed upon 12 strategies to manage invasive plants. The strategies focused primarily on 10 weeds which were considered to have a high potential for broad, significant impacts on natural ecosystems in the next 50 years and for which feasible management strategies could be defined. Each strategy consisted of one or more supporting actions, many of which were spatially linked to IBRA (Interim Biogeographical Regionalisation of Australia) bioregions. The first strategy was an over-arching recommendation for improved mapping, information sharing, education and extension efforts in order to facilitate the more specific weed management strategies. The 10 more specific weed management strategies targeted the control and/or eradication of the following high-impact exotic plants: mesquite, parkinsonia, rubber vine, bellyache bush, cacti, mother of millions, chinee apple, athel pine and prickly acacia, as well as a separate strategy for eradicating all invasive plants from one key threatened ecological community, the GAB (Great Artesian Basin dependant) mound springs. Experts estimated the expected biodiversity benefit of each strategy as the reduction in area that an invasive plant species is likely to dominate in over a 50-year period, where dominance was defined as more than 30% coverage at a site. Costs were estimated in present day terms over 50 years largely during follow up discussions post workshop. Cost-effectiveness was then calculated for each strategy in each bioregion by dividing the average expected benefit by the average annual costs. Overall, the total cost of managing 12 invasive plant strategies over the next 50 years was estimated at $1.7 billion. It was estimated that implementation of these strategies would result in a reduction of invasive plant dominance by 17 million ha (a potential 32% reduction), roughly 14% of the LEB. If only targeting Weeds of National Significance (WONS), the total cost was estimated to be $113 million over the next 50 years. Over the next 50 years, $2.3 million was estimated to eradicate all invasive plant species from the Great Artesian Basin Mound Springs threatened ecological community. Prevention and awareness programs were another key strategy targeted across the Basin and estimated at $17.5 million in total over 50 years. The cost of controlling, eradicating and containing buffel grass were the most expensive, over $1.5 billion over 50 years; this strategy was estimated to result in a reduction in buffel grass dominance of a million ha in areas where this species is identified as an environmental problem. Buffel grass has been deliberately planted across the Basin for pasture production and is by far the most widely distributed exotic species. Its management is contentious, having economic value to many graziers while posing serious threats to biodiversity and sites of high cultural and conservation interest. The strategy for containing and locally eradicating buffel grass was a challenge to cost based on expert knowledge, possibly because of the dual nature of this species as a valued pastoral grass and environmental weed. Based on our conversations with experts, it appears that control and eradication programs for this species, in conservation areas, are growing rapidly and that information on the most cost-effective strategies for this species will continue to develop over time. The top five most cost-effective strategies for the entire LEB were for the management of: 1) parkinsonia, 2) chinee apple, 3) mesquite, 4) rubber vine and 5) bellyache bush. Chinee apple and mother of millions are not WONS and have comparatively small populations within the semi-arid bioregions of Queensland. Experts felt that there was an opportunity to eradicate these species before they had the chance to develop into high-impact species within the LEB. Prickly acacia was estimated to have one of the highest benefits, but the costs of this strategy were high, therefore it was ranked 7th overall. The buffel grass strategy was ranked the lowest (10th) in terms of cost effectiveness. The top five most cost-effective strategies within and across the bioregions were the management of: 1) parkinsonia in the Channel Country, 2) parkinsonia in the Desert Uplands, 3) mesquite in the Mitchell Grass Downs, 4) parkinsonia in the Mitchell Grass Downs, and 5) mother of millions in the Desert Uplands. Although actions for several invasive plant species like parkinsonia and prickly acacia were concentrated in the Queensland part of the LEB, the actions involved investing in containment zones to prevent the spread of these species into other states. In the NT and SA bioregions of the LEB, the management of athel pine, parkinsonia and cacti were the main strategies. While outside the scientific research goals of study, this work highlighted a number of important incidental findings that led us to make the following recommendations for future research and implementation of weed management in the Basin: • Ongoing stakeholder engagement, extension and participation is required to ensure this prioritisation effort has a positive impact in affecting on-ground decision making and planning. • Short term funding for weed management was identified as a major reason for failure of current efforts, hence future funding needs to be secure and ongoing. • Improved mapping and information sharing is essential to implement effective weed management. • Due to uncertainties in the outcomes and impacts of management options, strategies should be implemented as part of an adaptive management program. The information provided in this report can be used to guide investment for controlling high-impact invasive plant species for the benefits of biodiversity conservation. We do not present a final prioritisation of invasive plant strategies for the LEB, and we have not addressed the cultural, socio-economic or spatial components necessary for an implementation plan. Cost-effectiveness depends on the objectives used; in our case we used the intactness of ecosystems as a surrogate for expected biodiversity benefits, measured by the extent that each invasive plant species is likely to dominate in a bioregion. When other relevant factors for implementation are considered the priorities may change and some actions may not be appropriate in some locations. We present the costs, ecological benefits and cost-effectiveness of preventing, containing, reducing and eradicating the dominance of high impact invasive plants through realistic management actions over the next 50 years. In doing so, we are able to estimate the size of the weed management problem in the LEB and provide expert-based estimates of the likely outcomes and benefits of implementing weed management strategies. The priorities resulting from this work provide a prospectus for guiding further investment in management and in improving information availability.

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This study investigated whether mixed-species designs can increase the growth of a tropical eucalypt when compared to monocultures. Monocultures of Eucalyptus pellita (E) and Acacia peregrina (A) and mixtures in various proportions (75E:25A, 50E:50A, 25E:75A) were planted in a replacement series design on the Atherton Tablelands of north Queensland, Australia. High mortality in the establishment phase due to repeated damage by tropical cyclones altered the trial design. Effects of experimental designs on tree growth were estimated using a linear mixed-effects model with restricted maximum likelihood analysis (REML). Volume growth of individual eucalypt trees were positively affected by the presence of acacia trees at age 5 years and this effect generally increased with time up to age 10 years. However, the stand volume and basal area increased with increasing proportions of E. pellita, due to its larger individual tree size. Conventional analysis did not offer convincing support for mixed-species designs. Preliminary individual-based modelling using a modified Hegyi competition index offered a solution and an equation that indicates acacias have positive ecological interactions (facilitation or competitive reduction) and definitely do not cause competition like a eucalypt. These results suggest that significantly increased in growth rates could be achieved with mixed-species designs. This statistical methodology could enable a better understanding of species interactions in similarly altered experiments, or undesigned mixed-species plantations.

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A 300-strong Angus-Brahman cattle herd near Springsure, central Queensland, was being fed Acacia shirleyi (lancewood) browse during drought and crossed a 5-hectare, previously burnt area with an almost pure growth of Dysphania glomulifera subspecies glomulifera (red crumbweed) on their way to drinking water. Forty cows died of cyanide poisoning over 2 days before further access to the plant was prevented. A digital image of a plant specimen made on a flat-bed scanner and transmitted by email was used to identify D glomulifera. Specific advice on the plant's poisonous properties and management of the case was then provided by email within 2 hours of an initial telephone call by the field veterinarian to the laboratory some 600 km away. The conventional method using physical transport of a pressed dried plant specimen to confirm the identification took 5 days. D glomulifera was identified in the rumen of one of two cows necropsied. The cyanogenic potential of D glomulifera measured 4 days after collection from the site of cattle deaths was 18,600 mg HCN/kg in dry matter. The lethal dose of D glomulifera for a 420 kg cow was estimated as 150 to 190 g wet weight. The plant also contained 4.8% KNO3 equivalent in dry matter, but nitrate-nitrite poisoning was not involved in the deaths.

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Two new fungi, Annellosympodia orbiculata and Scolecostigmina flagellariae, on Acacia ligulata and Flagellaria indica, respectively, from Australia are described and illustrated. The former species is placed in the new genus Annellosympodia, which is characterised by an unusual combination of features, viz. fasciculate conidiogenous cells (conidiophores reduced to conidiogenous cells), holoblastic conidiogenesis with sympodial, but rectilinear proliferation leaving annular structures and lateral conspicuous conidiogenous loci, and rhexolytic conidial secession. The generic placement of these two fungi is discussed.

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The Burdekin Rangelands is a diverse area of semi-arid eucalypt and acacia savannah covering six million hectares in north eastern Australia. The major land use is cattle grazing on 220 commercial cattle properties (average size 26,000 ha) each carrying on average 2600 adult equivalents. Production was the focus of the beef industry and support agencies prior to the mid 1980's. Widespread land degradation during the 1980's led to a grassroots realisation that environmental impacts, including water quality had to be addressed for the beef industry to attain sustainability. The formation of a series of producer based landcare gropus and the support of several Queensland and Australian government research and extension agencies led to a greater awareness and adoption of sound grazing land management practices (Shepherd 2005).

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Painted apple moth Teia anartoides Walker (Lepidoptera: Lymantriidae), a native to Australia, was discovered in Auckland, New Zealand in late 1999 and eradicated by 2006. It was recognised in 2002 that biological control would be the most effective long-term control strategy if eradication was unsuccessful, and a search was initiated for potential biocontrol agents in Australia. In 2003, autumn and spring surveys were undertaken in Victoria, Tasmania and South Australia of the guild of parasitoid natural enemies of T. anartoides. Eggs, larvae and pupae were collected and held to rear out any parasitoids. In addition, localised searches were made in Queensland in late 2003 early 2004 and laboratory-reared juvenile stages of T. anartoides were released for recapture in both Victoria and Queensland. Acacia dealbata Link (Fabales: Fabaceae) was the main plant from which T. anartoides was recovered, followed by apple. Most T. anartoides samples were collected from Victoria and Tasmania. Eighteen species from 13 genera of egg, larval and pupal parasitoids were reared and included Diptera (Tachinidae) and Hymenoptera (Braconidae, Encyrtidae, Eulophidae and Ichneumonidae). Of the seven Hymenopteran genera recovered from the larval stage, the most common in Victoria and Tasmania was a previously unidentified larval parasitoid Cotesia Cameron (Hymenoptera: Braconidae) sp. Echthromorpha intricatoria (Fabricius) (Hymenoptera: Ichneumonidae) was the dominant pupal parasitoid. The survey showed that the parasitoid complex associated with T anartoides is structurally very similar to that on other pest Lymantriidae in the northern hemisphere such as gypsy moth (Lymantria dispar L.) (Lepidoptera: Lymantriidae). Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) was recorded for the first time in Australia.

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The aim of this project was to investigate the suitability of thinnings from a range of plantation species for use as vineyard posts. The hardwood plantation species examined were Eucalyptus grandis, E. globulus, E. pilularis, E. dunnii, E. cladocalyx and Corymbia maculata, while Acacia mearnsii was obtained from natural regrowth. The softwood plantation species were P. elliottii, P. radiata and Araucaria cunninghamii. Variables examined included: three air drying regimes; microwave conditioning of E. grandis and E. globulus; two preservative treatments for hardwoods (alkaline copper quaternary compound (ACQ) and pigment emulsified creosote (PEC)); and two preservative treatments for softwood species (ACQ and, for Pinus radiata copper chromium arsenic (CCA)). A further aim was to install treated posts in commercial vineyards for demonstration purposes. From an earlier trial of three hardwood species treated with PEC, demonstration posts previously installed were also to be inspected annually for three years, and any movement of polycyclic aromatic hydrocarbons (PAH) from the posts monitored.