Sistemas agrícolas sustentáveis para regiões semi-áridas.

Resumo: A maioria dos sistemas de produção em prática no trópico semi-árido brasileiro pela agricultura familiar apresenta baixa ou nenhuma sustentabilidade, devido ao uso de tecnologias quase sempre agressivas ao ecossistema. Como consequência, observa-se, nos sertões nordestinos degradação ambiental generalizada, baixa produtividade das atividades agrícolas, pastoris e madeireiras, inviabilização da agricultura, queda da qualidade devida e êxodo rural acentuado. Urge, pois, que se forneça ao agricultor alternativas de sistemas de produção sustentáveis que atendam a quatro objetivos, quais sejam, a fixação da agricultura migratória, a adequação do manejo pastoril, a racionalização da produção de madeira e a uma forte integração dessas atividades. Para tanto, deve-se: excluir as queimadas, substituir o desmatamento pelo raleamento da vegetação lenhosa, manter um aporte substancial de matéria orgânica, utilizar Ieguminosas como fonte de adubo verde, ajustar a carga animal para a capacidade de suporte da área e adotar-se o corte seletivo e manejo da rebrota na exploração madeireira. A adoção dessas tecnologias na certa contribuirá: para a viabilização ecológica, social e econômica da agricultura familiar nos serões nordestinos, para a sustação dos processos de degradação ambiental, para a melhoria da qualidade de vida da população e para a redução do êxodo rural.

Melhoramento genético participativo: uma nova perspectiva para o manejo da diversidade genética do semi-árido nordestino.

2004

Estudo de caso da eficiência econômica e viabilidade financeira da produção de morango em sistema semi-hidropônico.

2011

Levantamento pedológico semi-detalhado (1:30.000) do Parque Estadual da Mata Seca, Município de Manga - MG.

Um dos pré-requisitos para o sucesso na seleção e implantação de áreas de pesquisa é o conhecimento preciso da distribuição dos solos e de seus atributos na paisagem. Isso pode ser obtido com o levantamento e mapeamento pedológico convencional e/ou através de técnicas de mapeamento digital de solos (MDS). Este trabalho apresenta os solos identificados no Parque Estadual da Mata Seca (PEMS), localizado no município de Manga, região norte do Estado de Minas Gerais. É parte integrante de um projeto maior, cujo objetivo é explorar novas técnicas de MDS em pequenas extensões territoriais, avaliar e validar seus produtos e estabelecer um protocolo de procedimentos para tal. Abrangendo a extensão de 10.281,44 ha, o PEMS tem sua geologia associada a coberturas cenozóicas derivadas de: (a) rochas pelíticocarbonáticas que compõem o Grupo Bambuí, de idade proterozóica, (b) arenitos cretáceos do Grupo Urucuia e, (c) depósitos quarternários resultantes do retrabalhamento do rio São Francisco. Os tipos e diversidade de material de origem foram os fatores preponderantes na formação e distribuição dos solos e na sua relação com os demais elementos formadores da paisagem local. Em termos gerais, a seguinte relação solo-paisagem pode ser observada na área: Latossolos Amarelos e Vermelho-Amarelos distróficos e de textura média ocupam os platôs (chapada) de relevo predominantemente plano, situados nas cotas mais elevadas do PEMS e sob domínio das coberturas relacionadas aos arenitos do Grupo Urucuia. A vegetação de Carrasco é exclusiva e marcante dessa paisagem, seja observando-a in loco, seja por meio de imagens de sensores remotos. Há uma faixa transicional entre esses domínios e aqueles situados em cotas ligeiramente inferiores, que são influenciados exclusivamente pelas rochas calcárias. A existência de eutrofismo associado à textura média em Latossolos Vermelho-Amarelos, Vermelhos, Chernossolos e Cambissolos (latossólicos), bem como a vegetação de Caatinga Arbórea Densa (de médio porte) são evidências do caráter transicional. As paisagens sob domínio das rochas pelítico-carbonáticas em que se desenvolve a Floresta Estacional Decidual Densa de alto porte (Mata Seca) são de maior extensão e complexidade na área. Nelas, o relevo e a proximidade do material de origem exercem ação modificadora na formação dos solos. As seguintes subordens taxonômicas foram observadas nesse domínio fisiográfico:Cambissolos Háplicos, Latossolos Vermelhos e Vermelhos-Amarelos, Chernossolos Háplicos e Argilúvicos, Vertissolos Háplicos, Plintossolos Pétricos, Gleissolos Háplicos e Melânicos. Dentre estas, os Latossolos Vermelho- Amarelos e Vermelhos juntamente aos Cambissolos Háplicos dominam em extensão, distribuindo-se em aproximadamente 87,0% das áreas sob influência calcária. Finalmente, nos depósitos quaternários do rio São Francisco, em relevo plano e sob Floresta Tropical Pluvial Perenifólia, foram mapeados Cambissolos Flúvicos e Neossolos Flúvicos em condições de boa drenagem, enquanto os Gleissolos Háplicos ocorrem nas áreas deprimidas, permanente ou temporariamente inundadas.

Semi-Supervised OWA Aggregation for Link-Based Similarity Evaluation and Alias Detection

T.Boongoen and Q. Shen. Semi-Supervised OWA Aggregation for Link-Based Similarity Evaluation and Alias Detection. Proceedings of the 18th International Conference on Fuzzy Systems (FUZZ-IEEE'09), pp. 288-293, 2009. Sponsorship: EPSRC

Birkhoff normal forms in semi-classical inverse problems

Iantchenko, A.; Sj?strand, J.; Zworski, M., (2002) 'Birkhoff normal forms in semi-classical inverse problems', Mathematical Research Letters 9(3) pp.337-362 RAE2008

Generalized semi-geostrophic theory on a sphere

Douglas, Robert; Cullen, M.J.P.; Roulston, I.; Sewell, M.J., (2005) 'Generalized semi-geostrophic theory on a sphere', Journal of Fluid Mechanics 531 pp.123-157 RAE2008

Rainfall infiltration and soil hydrological characteristics below ancient forest, planted forest, and grassland in a temperate northern climate

How rainfall infiltration rate and soil hydrological characteristics develop over time under forests of different ages in temperate regions is poorly understood. In this study, infiltration rate and soil hydrological characteristics were investigated under forests of different ages and under grassland. Soil hydraulic characteristics were measured at different scales under a 250 year old grazed grassland (GL), a six (6 yr) and 48 (48 yr) year old Scots pine (Pinus sylvestris) plantation, remnant 300 year old individual Scots pines (OT) and a 4000 year old Caledonian Forest (AF). In-situ field saturated hydraulic conductivity (Kfs) was measured and visible root:soil area was estimated from soil pits. Macroporosity, pore structure, and macropore connectivity were estimated from X-ray tomography of soil cores, and from water-release characteristics. At all scales the median values for Kfs, root fraction, macro-porosity and connectivity values tended to AF > OT > 48 yr > GL > 6 yr, indicating that infiltration rates and water storage increased with forest age. The remnant Caledonian Forest had a huge range of Kfs (12 to > 4922 mm h-1), with maximum Kfs values 7 to 15 times larger than 48-year-old Scots pine plantation, suggesting that undisturbed old forests, with high rainfall and minimal evapotranspiration in winter, may act as important areas for water storage and sinks for storm rainfall to infiltrate and transport to deeper soil layers via preferential flow. The importance of the development of soil hydrological characteristics under different aged forests is discussed.

Wybiórczość siedliskowa dzięcioła średniego Dendrocopos medius w zróżnicowanych ekosystemach leśnych

Wydział Biologii

Ziołolecznictwo w medycynie komplementarnej Polonii argentyńskiej z prowincji Misiones. Studium z zakresu etnobotaniki medycznej

Wydział Historyczny: Instytut Etnologii i Antropologii Kulturowej

Os motivos da não erupção dos terceiros molares

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária

A General Theory of Semi-Unification

Various restrictions on the terms allowed for substitution give rise to different cases of semi-unification. Semi-unification on finite and regular terms has already been considered in the literature. We introduce a general case of semi-unification where substitutions are allowed on non-regular terms, and we prove the equivalence of this general case to a well-known undecidable data base dependency problem, thus establishing the undecidability of general semi-unification. We present a unified way of looking at the various problems of semi-unification. We give some properties that are common to all the cases of semi-unification. We also the principality property and the solution set for those problems. We prove that semi-unification on general terms has the principality property. Finally, we present a recursive inseparability result between semi-unification on regular terms and semi-unification on general terms.

Monitoring the vegetation start of season (SOS) across the island of Ireland using the MERIS global vegetation index

The aim of this study was to develop a methodology, based on satellite remote sensing, to estimate the vegetation Start of Season (SOS) across the whole island of Ireland on an annual basis. This growing body of research is known as Land Surface Phenology (LSP) monitoring. The SOS was estimated for each year from a 7-year time series of 10-day composited, 1.2 km reduced resolution MERIS Global Vegetation Index (MGVI) data from 2003 to 2009, using the time series analysis software, TIMESAT. The selection of a 10-day composite period was guided by in-situ observations of leaf unfolding and cloud cover at representative point locations on the island. The MGVI time series was smoothed and the SOS metric extracted at a point corresponding to 20% of the seasonal MGVI amplitude. The SOS metric was extracted on a per pixel basis and gridded for national scale coverage. There were consistent spatial patterns in the SOS grids which were replicated on an annual basis and were qualitatively linked to variation in landcover. Analysis revealed that three statistically separable groups of CORINE Land Cover (CLC) classes could be derived from differences in the SOS, namely agricultural and forest land cover types, peat bogs, and natural and semi-natural vegetation types. These groups demonstrated that managed vegetation, e.g. pastures has a significantly earlier SOS than in unmanaged vegetation e.g. natural grasslands. There was also interannual spatio-temporal variability in the SOS. Such variability was highlighted in a series of anomaly grids showing variation from the 7-year mean SOS. An initial climate analysis indicated that an anomalously cold winter and spring in 2005/2006, linked to a negative North Atlantic Oscillation index value, delayed the 2006 SOS countrywide, while in other years the SOS anomalies showed more complex variation. A correlation study using air temperature as a climate variable revealed the spatial complexity of the air temperature-SOS relationship across the Republic of Ireland as the timing of maximum correlation varied from November to April depending on location. The SOS was found to occur earlier due to warmer winters in the Southeast while it was later with warmer winters in the Northwest. The inverse pattern emerged in the spatial patterns of the spring correlates. This contrasting pattern would appear to be linked to vegetation management as arable cropping is typically practiced in the southeast while there is mixed agriculture and mostly pastures to the west. Therefore, land use as well as air temperature appears to be an important determinant of national scale patterns in the SOS. The TIMESAT tool formed a crucial component of the estimation of SOS across the country in all seven years as it minimised the negative impact of noise and data dropouts in the MGVI time series by applying a smoothing algorithm. The extracted SOS metric was sensitive to temporal and spatial variation in land surface vegetation seasonality while the spatial patterns in the gridded SOS estimates aligned with those in landcover type. The methodology can be extended for a longer time series of FAPAR as MERIS will be replaced by the ESA Sentinel mission in 2013, while the availability of full resolution (300m) MERIS FAPAR and equivalent sensor products holds the possibility of monitoring finer scale seasonality variation. This study has shown the utility of the SOS metric as an indicator of spatiotemporal variability in vegetation phenology, as well as a correlate of other environmental variables such as air temperature. However, the satellite-based method is not seen as a replacement of ground-based observations, but rather as a complementary approach to studying vegetation phenology at the national scale. In future, the method can be extended to extract other metrics of the seasonal cycle in order to gain a more comprehensive view of seasonal vegetation development.

Invertebrate diversity in Irish and British forests

Ireland and Britain were once covered in natural forest, but extensive anthropogenic deforestation reduced forest cover to less than 1% and 5 %, respectively, by the beginning of the 20th century. Large-scale afforestation has since increased the level of forest cover to 11% in Ireland and 12% in Britain, with the majority of planted forests comprising small monoculture plantations, many of which are of non - native conifer tree species. At present the forest cover of Ireland and Britain generally consists of small areas of remnant semi-natural woodland and pockets of these plantation forests within a predominantly agricultural landscape. Invertebrates comprise a large proportion of the biodiversity found within forested habitats. In particular, spiders and carabid beetles play an important role in food webs as both predators and prey and respond to small-scale changes in habitat structure, meaning they are particularly sensitive to forest management. Hoverflies play an important role in control and pollination and have been successfully used as indicators of habitat disturbance and quality. This research addressed a number of topics pertinent to the forest types present in the contemporary Irish and British landscapes and aimed to investigate the invertebrate diversity of these forests. Spiders and carabid beetles were sampled using pitfall trapping and hoverflies were sampled using Malaise net trapping. Topics included the impacts of afforestation, the importance of open space, the choice of tree species, and the use of indicators for biodiversity assessment, as well as rare native woodlands and the effect of grazing on invertebrate diversity. The results are discussed and evidence-based recommendations are made for forest policy and management to protect and enhance invertebrate biodiversity in order to promote sustainable forest management in Ireland and Britain.

Application of semi-automated strain analysis techniques and anisotropy of magnetic susceptibility in fold and thrust belts

Quantitative analysis of penetrative deformation in sedimentary rocks of fold and thrust belts has largely been carried out using clast based strain analysis techniques. These methods analyse the geometric deviations from an original state that populations of clasts, or strain markers, have undergone. The characterisation of these geometric changes, or strain, in the early stages of rock deformation is not entirely straight forward. This is in part due to the paucity of information on the original state of the strain markers, but also the uncertainty of the relative rheological properties of the strain markers and their matrix during deformation, as well as the interaction of two competing fabrics, such as bedding and cleavage. Furthermore one of the single largest setbacks for accurate strain analysis has been associated with the methods themselves, they are traditionally time consuming, labour intensive and results can vary between users. A suite of semi-automated techniques have been tested and found to work very well, but in low strain environments the problems discussed above persist. Additionally these techniques have been compared to Anisotropy of Magnetic Susceptibility (AMS) analyses, which is a particularly sensitive tool for the characterisation of low strain in sedimentary lithologies.