Orientador: Leonardo Theodoro Büll / Banca: CarlosAlexandre Costa Crusciol / Banca: Takashi Muraoka / Resumo: A manutenção dos resíduos vegetais na superfície do solo é essencial para a sustentabilidade do sistema plantio direto, para tanto, é fundamental a seleção de coberturas vegetais com elevada capacidade de produção de massa seca, principalmente, em regiões onde as condições climáticas são favoráveis à rápida decomposição, além do estabelecimento de manejos da palhada que minimizem esse efeito, visando à proteção superficial do solo, formação de palhada, bem como reciclagem de nutrientes, com impacto direto nos atributos químicos do solo e na resposta das culturas subseqüentes ou em rotação. Assim o objetivo do trabalho foi avaliar a persistência da palhada de espécies de cobertura em função da aplicação de silicato e calcário e a resposta da cultura do feijão em sucessão em semeadura direta. O delineamento experimental utilizado foi em blocos ao acaso disposto em um esquema fatorial 3x5, com quatro repetições. O trabalho foi desenvolvido em estufa, no Departamento de Produção Vegetal, pertencente à Faculdade de Ciências Agronômicas - UNESP, Campus Botucatu. As parcelas foram constituídas por cinco doses de silicato de cálcio, calculadas em função da quantidade necessária para elevar a saturação por bases a 70%, dispostas da seguinte forma: 1 - 0 de silicato cálcio e 100% de calcário; 2 - 25% de silicato de cálcio e 75% de calcário; 3 - 50% de silicato de cálcio e 50% de calcário; 4 - 75% de silicato de cálcio e 25% de calcário; 5 - 100% de ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The maintenance of residual vegetation on the surface of the soil is essential for the sustainability no till, therefore, is essential the selection of covering vegetation with an increase capacity for the production of dry mass, especially in regions where climate conditions are favorable for rapid decomposition, along with establishing ways to handle the ground cover to minimize this effect, aiming for the protection of the soil surface, ground cover formation, as well as nutrients recycling, with direct impact on chemical properties of the soil and on response to subsequent or rotation crop. Therefore, the objective of the research was to evaluate the continued usage of the ground cover species as in function of the correction of the soil with silicate and lime and the response of the beans crop in succession in the direct plantation system. The experimental outlined used was the random blocks arranged in a 3x5 factorial design, with four replication. The experiment was developed in greenhouse, in the Department of Agriculture, of the Faculdade de Ciências Agronômicas - FCA - UNESP, Campus Botucatu. The plots were composed by five doses of calcium silicate, calculated as a function of the quantity necessary to increase base saturation to 70%, arranged as follows: 1 - 0% calcium silicate and 100% lime; 2 - 25% calcium silicate and 75% lime; 3 - 50% calcium silicate and 50% lime; 4 - 75% calcium silicate and 25% lime; 5 - 100% calcium silicate and 0% lime and three species of cover crops: millet (Pennisetum americanum L) beard grass (Brachiaria brizantha) pigeon pea (Cajanus cajan L.). The lime used was a mixture of CaCO3 and MgCO3 PA, so as to obtain the same proportions of Ca and Mg, both in the lime and in the silicate, this way varying, only the silicon content in each treatment. The parameters analyzed were: content and accumulation of nutrients ...(Complete abstract, click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:22:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-01-30Bitstream added on 2014-06-13T18:48:46Z : No. of bitstreams: 1 fernandes_fa_me_botfca.pdf: 465475 bytes, checksum: 063d7036f70ae424700b2f7818e66ed8 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A manutenção dos resíduos vegetais na superfície do solo é essencial para a sustentabilidade do sistema plantio direto, para tanto, é fundamental a seleção de coberturas vegetais com elevada capacidade de produção de massa seca, principalmente, em regiões onde as condições climáticas são favoráveis à rápida decomposição, além do estabelecimento de manejos da palhada que minimizem esse efeito, visando à proteção superficial do solo, formação de palhada, bem como reciclagem de nutrientes, com impacto direto nos atributos químicos do solo e na resposta das culturas subseqüentes ou em rotação. Assim o objetivo do trabalho foi avaliar a persistência da palhada de espécies de cobertura em função da aplicação de silicato e calcário e a resposta da cultura do feijão em sucessão em semeadura direta. O delineamento experimental utilizado foi em blocos ao acaso disposto em um esquema fatorial 3x5, com quatro repetições. O trabalho foi desenvolvido em estufa, no Departamento de Produção Vegetal, pertencente à Faculdade de Ciências Agronômicas – UNESP, Campus Botucatu. As parcelas foram constituídas por cinco doses de silicato de cálcio, calculadas em função da quantidade necessária para elevar a saturação por bases a 70%, dispostas da seguinte forma: 1 – 0 de silicato cálcio e 100% de calcário; 2 - 25% de silicato de cálcio e 75% de calcário; 3 – 50% de silicato de cálcio e 50% de calcário; 4 – 75% de silicato de cálcio e 25% de calcário; 5 - 100% de... / The maintenance of residual vegetation on the surface of the soil is essential for the sustainability no till, therefore, is essential the selection of covering vegetation with an increase capacity for the production of dry mass, especially in regions where climate conditions are favorable for rapid decomposition, along with establishing ways to handle the ground cover to minimize this effect, aiming for the protection of the soil surface, ground cover formation, as well as nutrients recycling, with direct impact on chemical properties of the soil and on response to subsequent or rotation crop. Therefore, the objective of the research was to evaluate the continued usage of the ground cover species as in function of the correction of the soil with silicate and lime and the response of the beans crop in succession in the direct plantation system. The experimental outlined used was the random blocks arranged in a 3x5 factorial design, with four replication. The experiment was developed in greenhouse, in the Department of Agriculture, of the Faculdade de Ciências Agronômicas – FCA – UNESP, Campus Botucatu. The plots were composed by five doses of calcium silicate, calculated as a function of the quantity necessary to increase base saturation to 70%, arranged as follows: 1 – 0% calcium silicate and 100% lime; 2 – 25% calcium silicate and 75% lime; 3 – 50% calcium silicate and 50% lime; 4 – 75% calcium silicate and 25% lime; 5 – 100% calcium silicate and 0% lime and three species of cover crops: millet (Pennisetum americanum L) beard grass (Brachiaria brizantha) pigeon pea (Cajanus cajan L.). The lime used was a mixture of CaCO3 and MgCO3 PA, so as to obtain the same proportions of Ca and Mg, both in the lime and in the silicate, this way varying, only the silicon content in each treatment. The parameters analyzed were: content and accumulation of nutrients ...(Complete abstract, click electronic access below)

Ground-based spectral imaging devices offer an important supplement to satellite imagery. Hand-held, ground-based sensors allow rapid, inexpensive measurements that are not affected by the earth’s atmosphere. They also provide a basis for high altitude spectral indices. We quantified the spectral reflectance characteristics of hard red spring wheat (Triticum aestivum cv. Westbred 936) in research plots subjected to either nitrogen or water stress in a two year study. Both types of stress reduced ground cover, which was evaluated by digital photography and compared with ten spectral reflectance indices. On plots with a similar soil background, simple indices such as the normalized difference vegetation index, ratio vegetation index, and difference vegetation index were equal to or superior to more complex vegetation indices for predicting ground cover. Yield was estimated by integrating the normalized difference vegetation index over the growing season. The coefficient of determination (r2) between integrated normalized difference vegetation index and final yield was 0.86. Unfortunately, none of these indices were able to differentiate between the intensity of green leaf color and ground cover fraction, and thus could not distinguish nitrogen from water stress. We developed a reflective index that can differentiate nitrogen and water stress over a wide range of ground cover. The index is based on the ratio of the green and red variants of the normalized difference vegetation index. The new index was able to distinguish nitrogen and water stress from satellite data using wavelengths less than 1000 nm. This index should be broadly applicable over a wide range of plant types and environments.

The increasing demand for and limited supply of fresh water necessitates an understanding of how human actions affect aquatic ecosystems. Anthropogenic impacts to these ecosystems occur in many forms including eutrophication, invasive species removals, and hydrologic alterations. Ground water extraction is one such action that can dramatically impact wetland hydrology and is increasing in occurrence globally as clean surface water resources are exhausted. Despite the importance of ground water extraction to meet human demand, little information is available concerning the response of vegetation communities to chronic ground water extraction. Over extraction is known to result in reduced water levels and duration, resulting in a shift towards more upland tolerant species; however, detailed information concerning the response of the individual species comprising these communities and how wetlands shift along with pumping regime remains unavailable. The following dissertation combines historical hydrology and ground cover vegetation data with recent monitoring to describe how ground cover (herbaceous species) and canopy (tree species) vegetation respond to fluctuations in hydrology and ground water extraction. Ground cover communities were extremely diverse with a total of 103 species being sampled in the historical ground cover vegetation dataset. Juncus repens was the most widely distributed species and was observed in 36% of all samples. The 29 species most widely observed in the ground cover strata (height) displayed relatively narrow ranges of preferred water depth and duration with Amphicarpum muhlenbergianum being found in the driest areas and Pontederia cordata and Ludwigia repens the wettest. In general species found in shallower water depths also tended to be found in locations with shorter hydroperiods, although woody species tended to found in areas with relatively shallow water depths with extended hydroperiod. Ground cover vegetation is extremely useful as an indicator of recent hydrology, although the hydrologic preference of the species in the current study does not reflect the assumed ecology of the species utilized by Florida Administrative Code 62-340.450. Additional research to validate and improve the accuracy of this classification system is required. When ground water extraction volumes in well fields was significantly reduced, ground cover communities were responsive, as was indicated by Permanova results (Before After Control Impact). All ground cover at wetlands located within well fields became more indicative of wetter conditions while control wetlands responding only to climate and weather all became drier. In contrast, several well fields displayed reductions in water levels and hydroperiod following extraction reductions. The shift in ground cover community indicates that ground water extraction has not produced an alternative stable state and restoration of these ecosystems is possible through alterations in ground water extraction volumes alone. As ground water extraction volumes were increased, tree communities responded by displaying increased occurrance of non-Taxodium sp. trees, mortality of wetland tree species, and light availability. All wetlands remained dominated by mature Taxodium sp. regardless of the amount of ground water impact indicating that each wetland has not yet shifted into a new community type as a result of non-Taxodium tree encroachment; however, recruitment and mortality patterns of both Taxodium and non-Taxodium species indicate this may occur in the future. Changes in light availability at the wetland floor associated with tree species is likely providing an additional feedback mechanism on ground cover communities. Results from this dissertation indicate that vegetation communities are extremely responsive to changes in hydrology and have shown significant changes associated with ground water extraction. These changes may not be permanent; however, and alterations in extraction volumes and timing can provide changes in vegetation communities even after decades. Routine long term monitoring should be conducted, in addition to critical assessments of current extraction volumes, to assess the current status of vegetation ecosystems and allow for individuals to best manage aquatic resources for all uses.

Orientador: Filipe Pereira Giardini Bonfim / Resumo: Objetivou-se com essa pesquisa avaliar tipos de cobertura do solo, época de formação e densidade da palhada sobre desempenho agronômico de espécies condimentares e fitossociologia das plantas espontâneas. Para isso, foram realizados dois experimentos distintos na Fazenda Experimental São Manuel, da Faculdade de Ciências Agronômicas - UNESP/Campus de Botucatu -SP. No primeiro experimento objetivou-se avaliar o desempenho produtivo das culturas salsinha (Petroselinum crispum L.) e cebolinha (Allium fistulosum L.) cultivadas em sistema orgânico com diferentes tipos de cobertura do solo, assim como a fitossociologia da comunidade infestante, em dois anos consecutivos, utilizando como tratamentos: palhada de sorgo (Sorghum bicolor (L.) Moench.); palhada de milheto (Pennisetum americanum (L.) Leeke); palhada de vegetação espontânea; plástico preto e solo sem cobertura. Já no segundo experimento buscou-se avaliar os efeitos das plantas de cobertura, densidade e época de formação da palhada, na produção e no manejo de plantas espontâneas em sistema de plantio direto orgânico de cebolinha. Esse experimento foi constituído por esquema fatorial 2x7, na qual o primeiro fator foi duas épocas de semeadura das plantas de cobertura (primavera e inverno) e o segundo fator foi a densidade de semeadura por metro linear das culturas de cobertura, sendo: sorgo 10, 20 e 40; milheto 25, 50 e 100 e solo sem cobertura. Avaliou-se das culturas condimentares as características agronômicas como número d... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this research was to evaluate types of soil cover, time of formation and density of straw on agronomic performance of condiment species and phytosociology of spontaneous plants. For this, two different experiments were carried out at the São Manuel Experimental Farm, of the Faculty of Agronomic Sciences - UNESP/Botucatu Campus -SP. In the first experiment, the objective was to evaluate the productive performance of the cultures of parsley (Petroselinum crispum L.) and scallions (Allium fistulosum L.) grown in an organic system with different types of soil cover, as well as the phytosociology of the weed community. Two years of consecutive cultivation were carried out, using as treatments: sorghum straw (Sorghum bicolor (L.) Moench.); millet straw (Pennisetum americanum (L.) Leeke); spontaneous vegetation straw; black plastic and bare ground. In the second experiment, the aim was to evaluate the effects of cover plants, density and time of straw formation, on the production and management of spontaneous plants in a system of organic no-tillage of scallions. This experiment consisted of a 2x7 factorial, in which the first factor was two sowing times of the cover plants (spring and winter) and the second factor was the sowing density per linear meter of the cover crops, being: sorghum 10, 20 and 40; millet 25, 50 and 100 and soil without cover. The agronomic characteristics of the condiment cultures were evaluated: number of leaves, average height of the plants,... (Complete abstract click electronic access below) / Doutor

The principal objective of this project was to determine whether Hedera helix was distributed randomly or exhibited host preferences within Drayton Wood, Norwich. 200 random tree samples >10cm diameter were studied. Of these, the CBH (circumference breast height), bark texture, abundance of H. helix and growth form were recorded. The percentage of ground covered by H. helix around the base of the sample trees was also recorded. Finally, the distance of the sample trees from the outer reaches of the wood and canopy cover were measured.Hedera helix was not distributed over potential host trees homogenously, but exhibited host associations. Quercus robur, Crataegus monogyna and Pinus sylvestris tree species were found to have a higher abundance of H. helix than expected by chance, whereas Acer pseudoplatanus and Betula pendula were found to have less H. helix vines than expected. Furthermore juvenile and mature vines were not distributed equally. Acer pseudoplatanus hosted more juveniles and less adults than expected, whereas Quercus robur and Pinus sylvestris hosted less juveniles and more mature vines than expected. Vines were not distributed independently of host size. Those trees <100cm CBH had a lesser stem abundance than expected, whereas those vines >100cm CBH had a greater stem abundance than expected. Host preference was exhibited for those large CBH trees with rough bark as opposed to large CBH trees with smooth bark. There was a higher abundance of H. helix (ground and trunk cover) with distance from the edge. Ground cover was greater under those trees hosting H. helix than those not supporting H. helix.Light did not play a major role in the distribution and abundance of H. helix (ground cover and trunk cover).Key Words: host selectivity, host size, bark texture, ground cover, location, light.

Cotton (<i>Gossypium hirsutum</i> L.) is a low residue crop, that may not provide sufficient surface residue to reduce erosion and protect the soil. A winter annual cover crop could alleviate erosion between cotton crops. Field experiments were conducted to evaluate selected winter annual cover crops for biomass production, ground cover, and N assimilation. The cover crop treatments were monitored under no-till and conventional tillage systems for the effects on soil moisture, cotton yield and quality. Six cover crop treatments, crimson clover (<i>Trifolium incarnatum</i> L.), hairy vetch (<i>Vicia vilosa</i> L.), hairy vetch and rye (<i>Secale cereale</i> L.), rye, wheat (<i>Triticum aestivum</i> L. amend. Thell.), and white lupin (<i>Lupinus albus</i> L.), and two tillage systems (conventional and no-till) were arranged in a split-plot design with four replications. Cover crop biomass production depended on climate conditions. Ground cover percent and N assimilation by cover crops were directly correlated with the amount of biomass produced within cover crop treatments. Within a range of near average winter temperatures, all cover crops except lupin provided enough ground cover to comply with federal conservation tillage standards. More ground cover remained on the soil surface further into the cotton growing season following the small grain treatments compared to the legume cover crop treatments. Soil moisture was higher (P < 0.05) under no-till compared to conventional tillage during the periods of drought in 1997. Tillage system had no effect on cotton yield and quality in 1995 and 1996. High cover crop biomass production coupled with an extended cotton growing season in 1995 resulted in higher lint yield for cotton grown following the hairy vetch + rye treatment compared with cotton grown following the wheat treatment. High heat unit accumulation in October 1995 led to the over maturity of cotton fiber and high micronaire values for cotton grown following all cover crop treatments. The high micronaire values (5.0 - 5.2) for cotton grown in all cover crop treatments except hairy vetch + rye (4.9), resulted in a market price deduction of 1.4 cents per kilogram of lint in 1995. All cover crops used in this experiment, with the exception of lupin, provided enough ground cover within a range of average winter temperatures to meet federal conservation requirements. The winter annual cover crops in a no-till cotton production system provided greater soil moisture conservation during periods of drought, and produced cotton yields and quality comparable to conventional tillage. / Master of Science

No description available.

Call number: LD2668 .T4 1985 G672 / Master of Science

Tendo em vista a importância de se obter um desenho urbano baseado no microclima e a possibilidade da utilização da vegetação arbórea como um elemento determinante na mitigação do desconforto urbano, este trabalho avaliou o efeito provocado por três diferentes arranjos espaciais de floresta urbana e do uso e ocupação do solo sobre a temperatura e umidade do entorno. A pesquisa foi realizada na cidade de Rio Claro/SP. As configurações escolhidas para análise foram uma avenida totalmente arborizada (S), uma praça (P) e um trecho de uma floresta periurbana (H) em áreas predominantemente residenciais com baixo gabarito de edificações. O trabalho de campo foi realizado em três dias consecutivos no período de seca e no período chuvoso. Os dados de temperatura e umidade foram obtidos por meio de registradores distribuídos ao longo de 200m nas ruas que se ramificavam para Norte, Sul, Leste e Oeste a partir do aglomerado arbóreo. As variáveis de velocidade e direção do vento foram registradas pela estação meteorológica do CEAPLA. Imagens termais do entorno das áreas foram obtidas com uma câmera termográfica. Foram aplicados questionários com os frequentadores das áreas verdes. Caracterizou-se o tecido urbano por meio de classificação supervisionada feita a partir de imagem multiespectral de alta resolução do satélite World-view 2. Polígonos circulares de 20m de raio foram gerados ao redor dos pontos onde os registradores permaneceram possibilitando correlacionar a porcentagem de cobertura com a temperatura e umidade do ponto. Mapas foram gerados no programa ARCMAP possibilitando visualizar a distribuição espacial da temperatura, amplitude e umidade relativa do ar nos locais. Nos locais do estudo nos horários mais quentes a temperatura e umidade do entorno variaram de 2 °C a 4 °C e 3 UR% a 15 UR%. Normalmente em ambientes semelhantes a variabilidade espacial da temperatura e umidade do ar não é alta e os fatores que mais influênciam essa mudança são a radiação solar e o vento local. Os valores mínimos de temperatura e máximos de umidade localizaram-se mais próximos à faixa florestada. As análises estatísticas mostram que ao considerar a variável distância a partir da área arborizada na análise geral, esta é considerada determinante na influência do aglomerado arbóreo no entorno, entretanto ao especificar a análise para cada local esta deixa de ser significativa nos locais H e P com significância somente no local S entre as distâncias 40 e 80m. Algumas coberturas, principalmente asfalto e copa de árvore, possuem correlação na variação da umidade e da temperatura dos pontos. A análise dos questionários mostra uma relação do conforto relatado com o fator de exposição ao sol. A observação qualitativa das imagens termais indica que os materiais de menor albedo como o asfalto superaquecem devido à radiação solar incidente, podendo chegar, nas horas mais quentes a 70°C, contribuindo para o desconforto. A forma mais barata e eficaz para solucionar este problema é promover o sombreamento das superfícies por meio da vegetação arbórea implantando corredores verdes na malha urbana com espécies de boa densidade foliar e copa ampla. / Given the importance of obtaining an urban design based on the microclimate and the possibility of the use of trees as a factor in mitigation of urban distress, this study evaluated the effect caused by three different spatial arrangements of urban forests and the use and occupation on soil in temperature and humidity of the environment in surroundings area. The research was conducted in the city of Rio Claro / SP. The configurations chosen for analysis were a fully forested avenue (S), a square (P) and a section from a periurban forest (H) in a area with predominantly residential buildings. Fieldwork was conducted in three consecutive days during the dry and rainy season. The air temperature and humidity were obtained by data loggers distributed over 200m in the streets that branched to the north, south, east and west from the tree cluster. The variable speed and wind direction were recorded by the meteorological station of CEAPLA. Thermal images of the surrounding areas were obtained with a thermographic camera. Questionnaires were applied to the green areas frequenters. Characterized the urban fabric by supervised classification made from multispectral image of high resolution two-view satellite World. Buffers with 20m were generated around the points where the data loggers remained possible to correlate the percentage of coverage with temperature and humidity of the point. Maps were generated in the ArcMap display showing the spatial distribution of temperature, amplitude and relative humidity at the sites. At the study sites, warmer periods in the surroundings showed temperatures and humidity ranged 2 °C to 4 °C and 3% RH to 15% RH. Usually in similar environments the spatial variability of temperature and humidity isn\'t high and the factors that influence this change are the local wind and solar radiation. The minimum temperature and maximum humidity were located closer to the forested area. Statistical analyzes show that when considering the distance variable in the overall analysis, this is considered decisive to influence of the tree cluster in the surroundings, however when the analysis is specific for each site the distance is no longer significant in the H and P sites and significant only in the place S between 40 and 80m distance. Some coverage, especially asphalt and canopy tree, show correlation between the variation of humidity and temperature points. Analysis of the questionnaires show a relationship between reported comforts with the exposure to the sun. A qualitative observation of thermal images indicate that the material of smaller reflectance as asphalt, overheat due to solar radiation, reaching, in the hottest hours at 70 ° C and contributes to discomfort. The most inexpensive and effective way to solve this problem is to promote the shading of surfaces by means of trees deploying green corridors in the urban area with good species of leaf density and ample canopy.