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A vegetation assessment was conducted to understand the effect of feral goats (Capra hircus) on the vegetation of Isolated Hill Scenic Reserve located in Southern Marlborough. New Zealand forests evolved without the pressure of mammalian herbivores but following human settlement they became subject to intensive browsing following the introduction of exotic mammals. This study focuses on the presence of feral goats. Interest arises from the settlement of other countries and the subsequent liberations of feral goats which are now considered to be responsible for the significant removal of native vegetation as well as playing a dominant role in erosion. Changes in plant communities have occurred with the pressure of goat browsing as well as secondary effects such as habitat degradation The purpose of this research was to investigate the changes in plant species composition since the initial and subsequent research conducted in 1985 and 1994. An analysis of previous work on the diet of multiple introduced ungulate species was also conducted. Previous studies were not limited to only feral goat studies and included other introduced herbivores to provide a broad overview of diets. The New Zealand Forest Service implemented a programme for monitoring the seral forest in Isolated Hill Scenic Reserve using standard Forest Service vegetation quadrants. 32 quadrants were established, including three exclosures, in various locations around the Reserve to allow assessment of feral goat impacts on seral forests (forest whose constituents are of varied age classes). Nine forest service plots, including three exclosures were re-measured and an additional nine plots were measured. Given the progression of vegetation change that has been observed during the course of this study, both analytically and observationally, Isolated Hill Scenic Reserve in its current state, involving the notable presence of feral goats and the vegetation types will continue to diminish in diversity.

Loss of native biological diversity is a world-wide problem of growing international concern. One of the main causes of native biodiversity loss is destruction and degradation of native habitat through land development for agriculture. The Waikato region is an example of the destruction and degradation of native habitat in association with the development and intensification of farming, including dairy farming. This thesis explores cultural reasons for the loss of native forest in the Waikato region, and reasons why fragments of native forest remain. The research involves a participant observation study of 'typical' dairy farm families for 9 months of the dairy year, in-depth interviews of dairy farmers who have protected a significant proportion of their land for conservation of native habitat, a questionnaire of dairy farmers, and an examination of dairy farm magazines and other literature to identify the values and attitudes that motivate dairy farmers in relation to land management and protection of native habitat. The title of the thesis suggests two elements that are important for understanding the loss and persistence of native forest in Waikato's farmed landscapes. Symbolic reason refers to the values, attitudes and perceptions of farmers that derive from socio-political and economic forces which encourage productivist practises that leave little opportunity for native forest to survive. Material agency refers to the local circumstances of particular farms and individual people which enable native forest to persist. The thesis argues that persistence of native forest depends on the idiosyncrasies of material circumstance in the face of relentless pressure to transform the production landscape for economic purposes. The thesis concludes with a suggestion that policies to assist survival of native habitat in farmed landscapes need to include ones that encourage the odds in favour of fortuitous circumstance. In the face of globalised economic pressures, policies for conservation of native biodiversity need to involve a 'portfolio' of measures that apply to individual landowners and the wider rural community by recognising, assisting and rewarding management for non-production values.

This study is concerned with programs to conserve remnant stands of native vegetation in the agricultural regions of South Australia and concentrates on the development of explicit evaluation procedures which reflect stated conservation objectives. As botanical data are available for stands of native vegetation in most of the agricultural regions, stands in a particular region are able to be compared rather than assessed in isolation. Based on a review of conservation evaluation schemes in Australia and overseas, a hierarchical evaluation procedure using multiple criteria to compare stands was applied to stands of vegetation in the Mount Lofty Ranges. The conservation objective, of preserving samples of all plant communities in a region, led to the analysis of existing botanical data from two surveys of the Mount Lofty Ranges, to provide the basis for an inventory of regional plant communities. These surveys included 52 remnant stands of native vegetation and employed a point-centred quarter plotless sampling technique to summarise the vegetation. Numerical classificatory analysis of the raw sampling point data produced a more comprehensive floristic summary than the results from the plotless sampling. These floristic groups were correlated with physical environmental variables to produce an inventory of 45 regional vegetation types, as the first stage in the conservation evaluation of stands. Evaluation criteria of size, species richness and species rarity were quantified and used to select examples of each vegetation type on the basis of overall satisfaction of the criteria. In addition, the smallest suite of stands, in which all the vegetation types were represented, was determined, and was shown to be 24 stands. All of these were included in the 37 stands chosen using the three criteria. A third evaluation stage used stand parameters such as plant community richness to give a priority ranking of the 37 stands. A polythetic divisive classification of the vegetation types was developed to provide a means of evaluating communities in stands of native vegetation yet to be sampled in the region, and of comparing the vegetation types with communities in existing reservesr Examination of species-sampling area relationships led to recommended plot sizes for such future vegetation surveys in the Mount Lofty Ranges. The ease of collecting floristic data and the extensive time involved in quantitative measurements suggest that all perennial plant species be recorded and only estimations be made of vegetation quantity and structure for each sampling plot. This study demonstrates the usefulness of numerical classification techniques for conservation evaluation, and of continuous variables to quantify criteria of conservation value; and the application of those criteria in an explicit, hierarchical conservation evaluation procedure.

Upland grasslands comprise a large proportion of the UK’s land area and are primarily used to graze sheep. These grasslands store large quantities of carbon (C). Changes in land use or climate could affect the ability of these soils to store C and the fluxes of other greenhouse gases associated with agricultural soils, nitrous oxide (N2O) and methane (CH4). Grazing substantially changes the cycling of C and nitrogen in grassland ecosystems, particularly through the deposition of rapidly degrading excreta, both dung and urine, on the soil. The major non-enteric greenhouse gas emissions associated with this type of extensive farming of ruminants are the emission of N2O and CH4 from soils affected by the animal’s excreta. This PhD project has investigated the cycling of sheep dung in two upland soils of different management regimes to investigate the effects imposed by the plant community. Dung incorporation was measured by capitalising on the natural difference in natural 13C abundance (δ13C ratios) between maize and native British vegetation, which permitted maize-derived sheep dung to be used as a 13C tracer of dung incorporation into soil. A physical and chemical soil fractionation methodology was used to isolate the distinct soil organic carbon (SOC) pools and ascertain the location of the dung C. There were differences between soils in dung C cycling, with more dung C being measured in semi-improved soils at experiment’s end. Throughout the one year timeframe of this experiment, most of the dung C was recovered in the particulate organic matter fraction. Changing the plant community did not have a measurable effect on dung C cycling within the experimental period. Urine patches in grazed pastures represent a major source of agriculture’s N2O emissions. The N2O, CH4 and CO2 fluxes from chambers treated with synthetic urine, synthetic urine and dung, or dung, and an untreated control in randomised block design at two sites were measured over one year. Relevant soil parameters were also measured at each sampling point. From this data N2O emission factors for sheep excreta at these sites were calculated. N2O emission factors were significantly different between sites, were different for dung and urine, and in all cases were less than the current default value used by countries utilising a Tier 1 methodology, according to the IPCC, to inventory N2O emissions derived from grazing livestock. Dietary manipulation has been proposed to increase certain components in urine that are thought to inhibit N2O emission with the aim of reducing livestock greenhouse gas emissions. One such urinary component is hippuric acid. Soil to which synthetic urine with incrementally increased quantities of hippuric acid were added were incubated, as were soils to which dung only and dung and synthetic urine had been added, as well as an untreated control. No significant effect of hippuric acid concentration was observed. N2O emissions from the dung only and dung and urine treatments were unusually high and surpassed those of the urine only treatments. This has been hypothesised to be due to fungal denitrification in the dung treatments or suppression of microbial activity due to ammonia toxicity in the urine-treated soils. The key conclusions from this PhD work are that the effect of dung deposition on SOC cycling may be quite small and appears to result in substitution of native SOC with dung C, rather than an increase in SOC; N2O emissions from sheep dung and urine deposition in semi-improved grasslands is likely to be very low and much lower than the current IPCC default value; and that in our incubation experiment there was no discernible impact of hippuric acid on N2O emissions, but it is possible that this is an experimental artefact.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-05-24T13:28:26Z No. of bitstreams: 1 Sandra Rodrigues da Silva.pdf: 2010525 bytes, checksum: 6d3b21507ed90cae2b2b621817937ecd (MD5) / Made available in DSpace on 2016-05-24T13:28:26Z (GMT). No. of bitstreams: 1 Sandra Rodrigues da Silva.pdf: 2010525 bytes, checksum: 6d3b21507ed90cae2b2b621817937ecd (MD5) Previous issue date: 2016-02-12 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The agriculture expansion results in the suppression of areas of native vegetation, creating areas of native vegetation fragmented, affecting resource availability and isolating plant and animal populations in Brazil and the world's ecosystems. One result of such expansion is to reduce pollinator populations, which play an important functional role in natural ecosystems and managed, such as agricultural crops. The yellow passion fruit (Passiflora edulis f. Flavicarpa., Passifloraceae) cultivation target of this study, is an agricultural culture dependent on cross-pollination and large bees (Xylocopa spp.) For the production of fruit. These bees have solitary habit and nest in tree trunks, stressing the importance of conservation of native vegetation areas to maintain their populations. Several studies indicate that proximity of native vegetation areas favors pollination and production of agricultural crops, for serving as a suitable habitat for pollinators. However, little is known about it in relation to the yellow passion fruit. With the low frequency Xylocopa genre of bees has been observed in the areas of the yellow passion fruit cultivation, farmers need to replace the process of natural pollination by hand pollination, which can be made with pollen of the day or stored, resulting in high costs for production. The aim of this study was to determine whether there is influence of the distance of the native vegetation in relation to areas of cultivation of passion fruit on the pollination and production at different times of the year, and to investigate the effectiveness of different manual pollination methods in production. The study was conducted in the Irrigated Perimeter of Maniçoba in Juazeiro- BA in eight areas of passion fruit crops with different distances from a native area of caatinga type in the dry and wet seasons of 2014 and 2015. The frequency of visits , the number, morphology, weight, the amount of pulp and fruit brix areas were compared. For manual pollination experiment were tested cross-pollination methods directed to the pollen day and pollen stored for 24 hours at an average temperature of 4-6 ° C, using gloved fingers, fingers without gloves, body and natural bee pollination. Furthermore, the viability was verified in vitro pollen germination and pollen tube growth in the stigma. Data were analyzed using the Tukey test, chi-square, ANOVA and Pearson's correlation test. Our results indicate that the distance alone did not affect fruit production, but when we include the season in the analysis, there was influence both the frequency of pollinators as the quantity and quality of fruits formed. In the dry, the nearest crop areas of native vegetation receive more frequent visits and produce larger fruit and higher quality. This season there was greater frequency of pollinators, quantity and quality of the fruit compared with the rainy season, indicating a more profitable production period and lower cost of hand labor for the producer. As for the directed pollination methods, the control showed the best quality fruits and method using the body of the bee had a higher fruit set. Treatment gloved fingers had the worst fruit. The day of pollen showed higher viability when the anthers were stored separately from the rest of the flower, and in-vitro germination of pollen showed greater success when the flower was fully stored. The higher the lowest pollen storage time is viability. Flowers pollinated with pollen stored did not form fruits, conversely to that observed for those pollinated with pollen of the day. Our results show the importance of natural pollination by bees Xylocopa gender in passion fruit crops, and the relevance of native vegetation for production, especially in the dry. So the natural pollination method seems to provide a good fruit quality and reduce labor costs for producers of this crop. / A expansão de áreas agrícolas ocasiona supressão da vegetação nativa, fragmentação da paisagem, modificação da disponibilidade de recursos e isolamento das populações vegetais e animais em ecossistemas do Brasil e do mundo. Uma das consequências de tal expansão é a redução das populações de polinizadores, que desempenham um papel funcional importante nos ecossistemas naturais e manejados, tais como as culturas agrícolas. O maracujá-amarelo (Passiflora edulis f. flavicarpa Deg., Passifloraceae) cultivo-alvo deste estudo, é uma cultura agrícola dependente de polinização cruzada e de abelhas de grande porte (Xylocopa spp.) para a produção de frutos. Essas abelhas possuem hábito solitário e nidificam em troncos de árvores, sendo importante a conservação de áreas de vegetação nativa para a manutenção de suas populações. Vários estudos indicam que a proximidade de áreas de vegetação nativa favorece a polinização e a produção de culturas agrícolas, por servirem de habitat adequado para polinizadores. No entanto, pouco se sabe a esse respeito em relação ao maracujá-amarelo. Com a baixa frequência de abelhas do gênero Xylocopa que tem sido observada nas áreas de cultivo do maracujá-amarelo, o produtor precisa substituir o processo de polinização natural pela polinização manual, que pode ser feita com pólen do dia ou armazenado, acarretando em altos custos para a produção. O objetivo deste estudo foi verificar se há influência da distância da vegetação nativa em relação a áreas de cultivo do maracujá-amarelo sobre a polinização e a produção em diferentes períodos do ano, bem como investigar a eficiência dos diferentes métodos de polinização manual na produção. O estudo foi desenvolvido no Perímetro Irrigado de Maniçoba, em Juazeiro- BA em oito áreas de cultivos de maracujá com diferentes distâncias em relação a uma área de vegetação nativa do tipo Caatinga, nas estações seca e chuvosa de 2014 e 2015. A frequência de visitas, o número, a morfometria, o peso, a quantidade de polpa e o brix dos frutos foram comparados entre áreas. Para o experimento de polinização manual foram testados métodos de polinização dirigida cruzada com pólen do dia e pólen armazenado por 24hs em temperatura média de 4-6°C, utilizando dedos com luvas, dedos sem luvas, corpo da abelha e polinização natural. Além disso, foi verificada a viabilidade, a germinação polínica in vitro e o crescimento do tubo polínico nos estigmas. Os dados foram analisados por meio do teste Tukey, Qui-quadrado, ANOVA e teste de correlação de Pearson. Nossos resultados indicam que a distância, isoladamente, não afetou a produção de frutos, mas quando incluímos a estação do ano na análise, houve influência tanto na freqüência dos polinizadores quanto na quantidade e qualidade dos frutos formados. Na seca, áreas de cultivos mais próximas da vegetação nativa recebem maior frequência de visitas e produzem frutos maiores e com maior qualidade. Nesta estação houve maiores frequência de polinizadores, quantidade e qualidade dos frutos quando comparada com o período chuvoso, indicando um período de produção mais rentável e com menor custo de mão-de-obra para o produtor. Quanto aos métodos de polinização dirigida, o controle apresentou frutos de melhor qualidade e o método utilizando o corpo da abelha apresentou uma maior taxa de frutificação. O tratamento dedos com luvas apresentaram os piores frutos. O pólen do dia apresentou maior viabilidade quando as anteras foram armazenadas separadamente do restante da flor, e a germinação in-vitro do pólen apresentou maior sucesso quando a flor foi armazenada integralmente. Quanto maior o tempo de armazenamento do pólen menor é sua viabilidade. Flores polinizadas com pólen armazenado não formaram frutos, inversamente ao observado para aquelas polinizadas com pólen do dia. Nossos resultados comprovam a importância da polinização natural realizada pelas abelhas do gênero Xylocopa nos cultivos de maracujá-amarelo, e a relevância da vegetação nativa para a produção, especialmente na seca. Portanto o método de polinização natural parece assegurar uma boa qualidade dos frutos e reduzir os custos de mão de obra para os produtores deste cultivo.

Made available in DSpace on 2015-04-11T13:54:46Z (GMT). No. of bitstreams: 1 Disseracao- Wagner Madruga.pdf: 1966142 bytes, checksum: 1c33d4a2e26590bb39f39141b79fb3d3 (MD5) Previous issue date: 2009-06-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Brazilian savannah is passing, in a more way accentuated in the recent two decades, for an accelerated process of substitution of his native vegetation for activities monocultoras for ends of products addressed to the external market and the savannah of the municipal district of Palmeirante - TO, is not different the this reality. Then the focus of this work of research pioneer in this area in study, that it aims at to provide a progress in the knowledge of the native flora and introduced that it composes that portion of the savannah, making a rising of the vegetable biodiversity in the borders of the areas of the cultivation of the soy, in eight properties that explore the soy cultivation, characterizing the transition of the vegetation of the savannah for areas of intensive cultivations accomplishing a check list of the species with their characteristics, use potentials, frequency of the species, habits of growths and of whole that occupation process obtaining information on the impact of those on the study area. Another outstanding die is the introduction of exotic species to the ecosystem of the savannah arrivals, or as seeds or as plants invasoras mixed opportunists the those, being this fact maybe one of the main contributions of this work, the need and urgency of to conserve and to protect, at all costs, under penalty of losing species and descaracterizar in an irreversible way this Bioma, that is the unconditional preservation of APPs, so that it is preserved like this and conserve the bank of seeds of the soil of the savannah, making possible the maintenance in the same of the basic elements to give support to future reliever actions of environmental recomposição, since many of those species are endemic and in a very private way it incorporates in his structure the own characteristics of this specific portion of the Brazilian savannah. / O cerrado brasileiro vem passando, de forma mais acentuada nas recentes duas décadas, por um processo acelerado de substituição de sua vegetação nativa por atividades monocultoras para fins de produtos direcionados ao mercado externo e o cerrado do município de Palmeirante - TO, não é diferente a esta realidade. Daí o foco deste trabalho de pesquisa pioneiro nesta região em estudo, que objetiva proporcionar um avanço no conhecimento da flora nativa e introduzida que compõe essa parcela do cerrado, fazendo um levantamento da biodiversidade vegetal nas bordas das áreas do cultivo da soja, em oito propriedades que exploram o cultivo de soja, caracterizando a transição da vegetação do cerrado para áreas de cultivos intensivos realizando um check list das espécies com suas características, potenciais de uso, freqüência das espécies, hábitos de crescimentos e de todo esse processo de ocupação obtendo informações sobre o impacto dessas sobre a área de estudo. Outro dado marcante é a introdução de espécies exóticas ao ecossistema do cerrado vindas, ou como sementes ou como plantas invasoras oportunistas misturadas a essas, sendo este fato talvez uma das principais contribuições deste trabalho, a necessidade e urgência de se conservar e proteger, a todo custo, sob pena de se perder espécies e descaracterizar de maneira irreversível este Bioma, que é a preservação incondicional das APPs, para que assim se preserve e conserve o banco de sementes do solo do cerrado, viabilizando a manutenção no mesmo dos elementos básicos para dar suporte a futuras ações mitigadoras de recomposição ambiental, já que muitas dessas espécies são endêmicas e de maneira muito particular incorpora em sua estrutura as características próprias desta parcela específica do cerrado brasileiro.