Geoinformação na gestão dos recursos hídricos em sub-bacia hidrográfica

By remote sensing, geodatabase digital processing, information and expeditions to Capivara's sub-basin, was possible to identify the changes in the landscape mainly the expansion of eucalyptus, sugar-cane, and orange trees, being the last two, mainly on the Periferic Depression of Basaltic Cuesta. A significant portion of the soil on this geological area is formed from sandstones, providing high permeability to them, making them important places to groundwater recharge areas as sensible to contamination by pesticides. Throughout last decade was observed that the native vegetation fragments stabilization, keeping a reason of 26.5% on the land used between 2000 and 2010. The pasture decrease being substituted by eucalyptus, sugar-cane and orange trees call attention for the changes in the agribusiness model demanded by the current economic and social necessity. Pasture decrease followed by erosions decrease on sub-basin is evidence that these two aspects are strongly related.

Alface americana fertirrigada com diferentes doses de ácido fosfórico e hidróxido de potássio

Fertirrigation with phosphoric acid has been considered as an option to avoid drips from clogging. In some cases, this acid cause soil acidification and it can be substituted bypotassium hydroxide. This study had the objective of evaluating the effects of different phosphoric acid and potassium hydroxide doses, applied via fertirrigation, on soil fertility, plant nutrition and lettuce yield, compared to the conventional fertilization system. The experiment was carried out in greenhouse, in the College of Agricultural Sciences, FCA/UNESP, Botucatu-SP-Brazil. The experimental design was the completely randomized block, with 6 treatments and 4 replications. Treatments consisted of the combinations of doses (25% and 50% of the recommended complete dose for the lettuce) and application ofcomplete dose (100%) of phosphorus (P) and potassium (K) applied via fertirrigation, and a control (conventional fertilization system). The results showed that P and K availability in soil and nutrient concentration in plants were affected by treatments. Low phosphorus and potassium doses, applied via fertirrigation, were not efficient for the appropriate development of lettuce plants. The results showed that agronomic characteristics and commercial lettuce were affected by doses and application systems, especially the treatment with application of P and K full dose fertirrigation.

Situação da agricultura irrigada no Brasil de acordo com o censo agropecuário 2006

Knowledge about irrigated agricultural area and its geographical distribution are of great importance to water resources management. Evolution of irrigated area according to the irrigation method allows an identification of rational water technologies. The aim of this work was to analyze the information presented in the agricultural census of 1995/1996 and of 2006. Brazil has an area of 4.45 million cultivated hectares with irrigation. It is noticed that according to the 1995/1996 census, the irrigated area increased 1.3 million hectares, a growth of 42%. The Southeast region surpasses the South region which had, in 1995/96, the largest irrigated area. The Northeast region is the third irrigated agricultural area with 22.12 %, while the Central-west and the Northern region together sum 14.7%. According to the agricultural census 2006 classification, sprinkler irrigation (without center pivot) method is the most used,followed by flood, center pivot, other methods, drip and furrow, representing 35.3%, 24.4%, 18.9%, 8.3%, 7.4% and 5.8%, respectively.

Aplicação de técnica de geoprocessamento em áreas degradadas de mata ciliar e sua correlação com qualidade da água numa subbacia hidrográfica

Studying the physical environment of a watershed is the basic condition for a successful planning of the riparian forest preservation, and for water production and conservation. The aims of the present study were to analyze and quantify the spatial and temporal evolution (1984 and 2010) using Landsat-5 satellite images of Cintra Stream sub-watershed, Botucatu, São Paulo State, Brazil, processed by the software IDRISI Andes, as well as to analyze the water quality through the parameters pH, EC, DO and BOD5 at 4 different sites in the years 1999, 2008 and 2009. Considering the 1076.48ha area of the sub-watershed, the pasture class of 1984 was reduced by 25.55% in 2010, resulting in an increase in the remaining classes. The most important class was native forest and reforestation since it had an increase of 5.08%, which indicates recovery of the riparian forest. Degraded areas were identified close to the inferior limit of the sub-watershed (P3 and P4), as well as local contamination (P1 and P2) with worsening of the water quality in the remaining sites in the periods 2008 and 2009. Recovery and management of the ecological succession of degraded areas and water quality monitoring at 1 and 2 sites will be necessary to reestablish the natural condition of the area studied.

Crescimento inicial do eucalipto em função da aclimatação em viveiro

This study aimed to evaluate the acclimatization effects in the Eucalyptus grandis vs. Eucalyptus urophylla seedlings nursery in their initial growth in two soils types, clay and sandy. The seedlings were planted in Plantmax substrate and in rice hulls plus vermiculite, and managed, after 60 days of the mass propagation (DAE), during the rustication. There were five different frequencies of subsurface drip irrigation, restoring the soil field capacity condition: F1, F2, F3 and F4, which were irrigated once, twice, three and four times a day, respectively, and FD, kept in continue irrigation until planting at 90 DAE. In a randomized block design with four replications, plant height (HPA) were evaluated at 6 and 13 months after planting and the diameter at breast height (DAP) at 13 months after planting. Findings show that water management at hardening phase seedlings had no influence on growth in both soils.

Um filtro gaussiano adaptativo para análise comparativa de imagens de radares e satélites meteorológicos

Meteorological satellite and radar data comparative analysis allows to correlate the precipitation structures observed in both images. Such analysis would make feasible the extension of the range of ground-based meteorological radars. In addition to the different spatial and temporal resolution of these images this comparative analysis presents difficulties due to the effects of rotation and distortion, besides the different formats, projections, and coordinate systems. This work employed an approach based on a Gaussian adaptive filter in order to compare such images. The statistical results obtained from the comparison of the images are matched to those produced by other methods.

Supressão de água em diferentes fases fenológicas do feijoeiro (Phaseolus vulgaris L.)

Bean (Phaseolus vulgaris L.) is widespread in the Brazilian social and economic scene. The hypothesis is that if the water supply is suppressed in just one of the five development stages of irrigated beans, it can result in yield reduction lower than 20%, allowing water economy. The objective of this study was to compare the performance of bean Carioca group IAC Alvorada yield components, with irrigation suppression in each of the five phenological phases (emergence, vegetative, flowering, grain filling and maturation) and no irrigation and irrigated in all stages. The study was conducted at Agronomical Sciences College, UNESP, Botucatu, SP, Brazil. The statistical design was the randomized block with seven treatments and four replications. Data were subjected to analysis of variance and t test at 5% probability. A rainfall event (58 mm) after planting allowed the successful emergence of seedling beans in plots where water would not be applied. The yield components were higher affect when there was irrigation's suppression at Vegetative phase and at Flowering phase. The treatments where occurred irrigation suppression at Maturation and at Emergence showed yield reduction of less than 20%, proving the hypothesis.

Variabilidade espacial na produção da alface em ambiente protegido

Este artigo mostra a dinâmica da água após ser aplicada sobre a superfície de um solo cultivado com alface, num sistema fechado de um ambiente protegido. A aplicação de água se deu por meio de um sistema de irrigação por gotejamento, com o CUD ( Coeficiente de Uniformidade de Distribuição ) igual a 97,06 %, o que garantiu uma ótima uniformidade de distribuição, desconsiderando como possíveis causas das variações de umidade do solo, a aplicação de lâminas variadas. Fazendo uso de técnicas de geoestatística, interpolando sessenta pontos amostrais de evaporação, umidade do solo e produtividade da alface, com as mesmas sessenta coordenadas para os três atributos, verificou-se que a umidade do solo, mesmo momentos após a irrigação, não permanece uniforme ao longo do sistema de irrigação, constatando-se que a evaporação local exerce influência de forma predominante sobre a dinâmica da água na superfície do solo. Concluiu-se que as regiões no interior da estufa de maiores evaporações, foram as de maiores variações de umidade do solo e na produção de massa verde da alface.

Influência de Manejos de irrigação sobre aspectos de Ecofisiologia e de produção da videira cv. Syrah / Paulsen 1103

O manejo de irrigação pode influenciar o comportamento ecofisiológico e a produção da videira. O objetivo desse trabalho, conduzido em 2010 em Petrolina – PE, no Submédio do Vale do São Francisco, foi avaliar a influência de diferentes estratégias de manejo de irrigação no potencial de água na folha e em aspectos qualitativos e quantitativos das uvas do primeiro ciclo de produção da videira cv. Syrah/Paulsen 1103. O sistema de irrigação utilizado foi gotejamento e a lâmina de água foi estimada com base na evapotranspiração da cultura. O delineamento experimental utilizado foi o de blocos casualizados, em 4 repetições e com 3 tratamentos: irrigação plena, realizada durante todo o ciclo de produção; a irrigação com déficit, onde a aplicação de água foi interrompida na fase fenológica de cacho fechado; e a irrigação com déficit controlado, onde a irrigação, também interrompida na fase de cacho fechado, foi eventualmente realizada após a interrupção, de acordo com o monitoramento da água no solo. A imposição de déficit hídrico às plantas favoreceu uma maior concentração de açúcares e a redução da acidez nos frutos, contribuindo para a melhoria da qualidade das uvas para vinificação.

Utilização de água residuária do processo pós-colheita do café na produção de mudas de cafeeiro

Intending to achieve better results on coffee production, the coffee producers began, since the 80s, to process the coffee postharvest, in order to ensure product's superior quality. However, with the processing, other problem appeared, the contamination of rivers, creeks, soil and water table from coffee wastewater (ARC). This paper had as main objective to use the ARC on the coffee plants' production verifying its viability and if the ARC is able to supply the coffee potassium requirements when they don't receive potassium chloride in the organic compound. The work was developed at Faculdade de Ciências Agronômicas - UNESP, Botucatu-SP, in a greenhouse located at Departamento de Engenharia Rural. The work consisted of 10 treatments on a 5×2 factorial (5 wastewater proportions of coffee after the harvest processing - 0%, 25%, 50%, 75% and 100% - and potassium chloride presence or absence in the composition), with 4 repetitions with a completely randomized statistical design. The ARC was applied each 48 hours in an irrigation depth of 10 mm. After 6 months, the plants' vegetative characteristic had been evaluated as well the chemical characteristics of the compound and of the plants. We observed that the treatments with potassium chloride presence showed worse vegetative characteristics compared with treatments which did not have KCl in its composition. Moreover, with the increase of the wastewater dosage, it happened a decrease in the vegetative characteristics, however an addition in the chemical characteristics of the compound. Also, the treatments without KCl presence and with 0% and 25% of coffee wastewater had been statistically equal, showing the viability in the use of the ARC in the production of coffee plants, since the compound does not contain KCl and that the water used in the composition is a mixture of 25% of ARC with 75% of common water.

Optimal moment to change pressure regulator and sprayer kit on center pivot irrigation machines: a theoretical proposal

A theoretical model was developed in order to determine the optimal moment for substituting the sprayer and pressure regulator kit on a center pivot irrigation machine. The model is based on the hypothesis that pressure regulator and sprayer deterioration decrease irrigation uniformity. To compensate the deficit that happens at under irrigated areas, an increase on irrigation depth is required. The model considers: additional water consumption and energy costs, maintenance and labor costs, as well as yield losses associated with under or over irrigated areas. The sum of all these components is compared to buying and installing a new spray kit cost, allowing the farmer to decide the best moment to renovate the sprayer and pressure regulator kits on a center pivot irrigation machine based on economic criteria.

Optimal moment to change pressure regulator and sprayer kit on center pivot irrigation machines: application to a study case

A theoretical model developed by the authors for determining the optimal moment to substitute sprayer and pressure regulator kit on a center pivot irrigating potatoes and beans has been applied. The methodology compares the sum of the costs due to additional consumption of water and energy, maintenance and labor, as well as yield losses associated to areas with deficit or over irrigation to the costs due to buy and install a new sprinkling set on the pivot. The results showed that for a reduction of 3.07% of the Hermann and Hein’s Uniformity Coefficient (UCh), the substitution of the sprinkling module on the pivot is justified when potatoes and beans are cultivated.

Perda de carga em mangueiras gotejadoras novas e usadas

This paper aims to determine the importance of emitter ́s local head loss in the hydraulic design of hose drip lines, as well as comparing the result of equations that calculate the local head loss; besides verifying the influence of iron precipitated at the hose head loss made in Brazil. The result found that localized head loss represents 23% of the total head loss; the equations showed significant results and the total head loss increased in an average of 20% after the irrigation system was used with water rich in iron.

Análise multivariada aplicada em bacias hidrográficas no município de Botucatu-SP

As imagens aerofotogramétricas de uma região registram os vários aspectos da paisagem, destacando a cobertura vegetal, a rede de drenagem e principalmente o relevo do terreno conjunto que caracterizam unidades morfométricas denominadas bacias hidrográficas. Neste trabalho aplicaram-se técnicas fotointerpretativas e estatística multivariada a variáveis do relevo, medidas em bacias hidrográficas de terceira ordem de ramificação pertencentes à bacia do rio Tiête no município de Botucatu-SP, com o objetivo de agrupar bacias segundo graus de similaridade, bem como inferir sobre a representatividade da distribuição espacial dos agrupamentos em relação ao Mapa Pedológico do Estado de São Paulo, da Embrapa de 1999. Foram utilizadas fotografias aéreas verticais, escala nominal aproximada 1:30000, (2005), cartas planialtimétricas escala 1:50000 e Mapa Pedológico do Estado de São Paulo. Foram estudadas 06 bacias hidrográficas de 3aordem de ramificação, situada na região fisiográfica denominada frente da cuesta abrangendo as unidades de solo Neossolos Litólicos (RL) e Latossolos Vermelhos distrófico (LVdf), sendo esta última predominante na área de estudo. O conjunto de variáveis de relevo mostrou-se eficiente no agrupamento das bacias conforme as unidades de solos ocorrentes, concordando com as unidades identificadas no Mapa Pedológico.

Fracionamento da fertirrigação e seu efeito na produção da alface sob ambiente protegido

Buscando quantificar o efeito do parcelamento da fertirrigação no desenvolvimento da alface, esta pesquisa procurou verificar o número de parcelas de fertirrigação que apresentasse o melhor desempenho no crescimento da cultura. O experimento se deu em blocos casualizados, com três repetições, quatro tratamentos de fertirrigação e três lâminas de irrigação (L1, L2 e L3). Em um dos tratamentos de fertirrigação (F1), toda a adubação necessária se deu no início do plantio; no tratamento F2, a metade da adubação se deu no início do plantio e a outra metade no meio do ciclo da cultura, uma vez planejada a colheita em 40 dias após o plantio; o tratamento F3 foi fracionado: 1/3 da adubação no início do plantio, 1/3 depois de 13 dias e o ultimo terço após 26 dias do plantio; o tratamento F4 seguiu o mesmo raciocínio, fracionando a aplicação em 4 partes, de 10 em 10 dias. Logo, os quatro tratamentos de fertirrigação receberam a mesma dosagem de fertilizantes. Os resultados permitiram concluir que a aplicação F1 resultou no pior desempenho, com massa fresca de 135,06 gramas por planta, enquanto o melhor resultado se deu no tratamento F2, com massa fresca de 161,40 g. Em todas as lâminas, o parcelamento F3 resultou em sistema radicular mais desenvolvido. O tratamento L1 apresentou em média maior desenvolvimento das raízes, seguido do L2 e L3. O tratamento L1 apresentou menor condutividade elétrica no extrato da solução dos vasos, sendo o único tratamento que diferiu estatisticamente dos demais.