924 resultados para condições climáticas


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The sugarcane is a widely adapted species to tropical climate and has made key role in economic development in Southeast and Northeast. The ability to adapt in different environments can be evaluated through the growth analysis and yield. This study aimed to evaluate the growth and yield of four sugarcane varieties (RB92579 and SP79-1011, RB931530 and RB93509) in the third ratoon. The experiment was conducted at the CECA/UFAL, Rio Largo (28 degrees 02'09 '' S, 35 degrees 49'43 '' W and 127m). The experimental design was randomized blocks. Was evaluated monthly the number of plants, height, leaf area index and stem diameter. The quality of raw material, dry matter and yield were evaluated at 360 DAC. The data were subjected to analysis of variance and means compared to each other by Tukey test. The results showed that the maximum tillering occurred at 90 DAC for all varieties, and the RB92579 showed greater tillering and greater height at 360 DAC. The variety RB931530 had superior diameter than the others. The RB92579 and RB93509 were higher than the others on the sugar production, dry matter and yield, however, differed ech only on the matter. Varieties RB92579 and RB931530 had similar levels of Brix, PCC and ATR. Since this latter variable responsible for developing the pricing of sugarcane industry.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Low voltage solar panels increase the reliability of solar panels due to reduction of in series associations the configurations of photovoltaic cells. The low voltage generation requires DCDC converters devices with high efficiency, enabling raise and regulate the output voltage. This study analyzes the performance of a photovoltaic panel of Solarex, MSX model 77, configured to generate an open circuit voltage of 10.5 V, with load voltage of 8.5 V, with short circuit current of 9 A and a power of 77 W. The solar panel was assembled in the isolated photovoltaic system configuration, with and without energy storage as an interface with a DCDC converter, Booster topology. The converter was designed and fabricated using SMD (Surface Mounted Devices) technology IC (integrated circuit) that regulates its output voltage at 14.2 V, with an efficiency of 87% and providing the load a maximum power of 20.88 W. The system was installed and instrumented for measurement and acquisition of the following data: luminosities, average global radiation (data of INPE Instituto Nacional de Pesquisas Espaciais), solar panel and environment temperatures, solar panel and DC-DC converter output voltages, panel, inverter, and battery charge output currents. The photovoltaic system was initially tested in the laboratory (simulating its functioning in ideal conditions of operation) and then subjected to testing in real field conditions. The panel inclination angle was set at 5.5°, consistent with the latitude of Natal city. Factors such as climatic conditions (simultaneous variations of temperature, solar luminosities and ra diation on the panel), values of load resistance, lower limit of the maximum power required by the load (20.88 W) were predominant factors that panel does not operate with energy efficiency levels greater than 5 to 6%. The average converter efficiency designed in the field test reached 95%

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A preservação de fungos fitopatogênicos por longos períodos de tempo é importante para que pesquisas possam ser realizadas a qualquer momento. Os fungos habitantes do solo são organismos que podem produzir estruturas de resistência em face de situações adversas, tais como ausência de hospedeiros e ou condições climáticas desfavoráveis para a sua sobrevivência. O objetivo deste trabalho foi desenvolver metodologias de preservação de estruturas de resistência para os fungos Fusarium oxysporum f.sp. lycopersici raça 2, Macrophomina phaseolina, Rhizoctonia solani AG4 HGI, Sclerotium rolfsii, Sclerotinia sclerotiorum e Verticillium dahliae. O delineamento foi inteiramente casualizado, com um método de produção de estruturas para cada fungo, submetido a três tratamentos [temperatura ambiente de laboratório (28±2ºC), de geladeira (5ºC) e de freezer (-20ºC)] e com dois frascos por temperatura. Mensalmente, e por um período de um ano, a sobrevivência e o vigor das colônias de cada patógeno foram avaliadas em meios de cultura específicos. Testes de patogenicidade foram realizados após um ano de preservação, com as estruturas que sobreviveram aos melhores tratamentos (temperatura) para todos os fungos. As melhores temperaturas (tratamentos) para preservar os fungos foram: a) F. oxysporum f.sp. lycopersici em temperatura de refrigeração e de freezer (5,2 e 2,9 x 10³ufc.g-1 de talco, respectivamente); b) M. phaseolina em temperatura de refrigeração [100% de sobrevivência (S) e índice 3 de vigor (V)] e S. rolfsii em temperatura ambiente (74,4% S e 1 V) e c) S. sclerotiorum e V. dahliae, ambos em temperatura de freezer (100% S e 3 V). Após um ano de preservação, somente V. dahliae perdeu a patogenicidade na metodologia desenvolvida.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Stabilization ponds are an effective sewage treatment alternative for the climatic conditions prevailing in Brazil. In the present work, a primary facultative pond was studied, in the city of Natal, Rio Grande do Norte, Northeast Brazil. The aim of this study was to evaluate the sedimentation dynamics in the facultative pond. The pond was divided in three section or zones along its length starting from the inlet end namely A1, A2 and A3. The research was accomplished in three phases. In the first the mapping of the sludge layer was done, sludge core samples were also collected for analysis for total, fixed and volatile solids and the depth of the sludge layer was determined using a portable echo sounder. In the second solids sedimentation rates were measured using traps placed in the inlet and outlet zones and in the third phase resuspension sludge was evaluate using a tracer. The amount accumulated sludge since the start operation was 13.583 m3. The sedimentation constant averages changed between 0.93 to 2.94 and 3.90 to 5.80 for the depths of 0.5 and 1.0 m respectively. The relationship between volatile and fixed solids (SV/SF) increased along the pond. The removal efficiencies were 52.12%, 36.09%, and 37.50% for BOD, COD and SS, respectively. The sludge accumulation model proposed had a good adjustment with 0.17 m3/hab.year rate. The results presented here demonstrated that the wind had a direct influence on the sedimentation of solids in this pond affecting the efficiency and sludge accumulation

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Availability of good quality water has been reduced vertiginously, over the last decade, in the world. In some regions, the water resources have high concentration of the dissolved salts, these characteristics of the water make it s use impossible. Water quality can be a limitation for irrigated agriculture, principally in regions of arid or semiarid climate where the water resources are generally saline and are exposed at high evaporation ratio. For that reason, precipitation of the salts occurs near the soil surface and those salts themselves cumulate in the vegetal tissue, reducing the soil fertility and crop production. The adoption of tolerant crop to the water salinity and soil salinity, adaptable to the climatic conditions is other emergent necessity. This work had the goal of studying the effects of four salinity levels of the irrigation water salinity and use of mulch, dried leaves of Forest mangrove (Acacia mangiumWilld), in cultivated soil with amaranth (Amaranthus cruentus, BRS Alegria variety), in greenhouse. It was utilized the transplant of plants to PVC columns, containing 30 kg of silty loam soil, 10 days after emerging, with space of 50 x 50 cm between lines. Treatments were composed by combination of four levels of salinity (0.147; 1.500; 3.000 e 4.500 dS m-1), obtained by addition NaCl (commercial) to irrigation water and soil with and without protection, by mulch. A factorial system 4 x 2 was used with four repetitions, totalizing 32 parcels. The concentrations of nutrients in soil solution have been evaluated, in the dry matter of the vegetal tissue (roots, stem, leaves and raceme residue), at the end of the vegetative cycle. The use of soil protection reduced time for the beginning inflorescence of plants, at the same time, the increase of the salinity delayed this phase of amaranth development. The use of the mulch effectively increased the height, stem diameter, area of the larger leaf, humidity and dry matter content and amaranth grain production. The vegetal species showed salinity tolerance to experimented levels. The adopted treatments did not affect the pH values, exchangeable cation contents, electrical conductivity of soil solution (EC1:5) and saturated extract (ECSE), and Ca+2, Mg+, Fe+2 and Mn+2 contents, in the soil solution. The increase of the salinity concentration in the irrigation water inhibited the mineralization process of the organic matter (OM) and, consequently, the efficiency in the it´s utilization by plants, at the same time, produced increase in the values of the exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR) and potassium adsorption ratio (PAR), in the soil solution. Therefore, the use of the mulch did not affect the first three parameters. The protein and nutrient contents: K+, Ca+2, P, Mg+2 e Cu+2, in amaranth grains, were improved by tillage condition. The raceme residues showed chemical/nutritional composition that makes advantageous its application in animal ration. In this context, it follows that amaranth tolerate the saline stress, of the irrigation water, until 4.500 dS m-1, temperature and relative humidity of the air predominant in the experimental environment

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The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

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The semiarid rainfall regime is northeastern Brazil is highly variable. Climate processes associated with rainfall are complex and their effects may represent extreme situations of drought or floods, which can have adverse effects on society and the environment. The regional economy has a significant agricultural component, which is strongly influenced by weather conditions. Maximum precipitation analysis is traditionally performed using the intensity-duration-frequency (IDF) probabilistic approach. Results from such analysis are typically used in engineering projects involving hydraulic structures such as drainage network systems and road structures. On the other hand, precipitation data analysis may require the adoption of some kind of event identification criteria. The minimum inter-event duration (IMEE) is one of the most used criteria. This study aims to analyze the effect of the IMEE on the obtained rain event properties. For this purpose, a nine-year precipitation time series (2002- 2011) was used. This data was obtained from an automatic raingauge station, installed in an environmentally protected area, Ecological Seridó Station. The results showed that adopted IMEE values has an important effect on the number of events, duration, event height, mean rainfall rate and mean inter-event duration. Furthermore, a higher occurrence of extreme events was observed for small IMEE values. Most events showed average rainfall intensity higher than 2 mm.h-1 regardless of IMEE. The storm coefficient of advance was, in most cases, within the first quartile of the event, regardless of the IMEE value. Time series analysis using partial time series made it possible to adjust the IDF equations to local characteristics

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Goat breeding in the state of Rio Grande do Norte, Brazil has promising economic possibilities, with the proper handling of the natural resources. The introduction of specialized animals has been one of the ways used to improve herd genetics and increase productivity. However, climate has been one of the regional factors that most interferes with the adaptation of the new genetic prevalence resulting from the introduction of exotic breeds, because in their country of origin, the air temperature during most of the year is lower than the animals body temperature. With this in mind, the aim of this study was to characterize behavioral, physiological and morphological profiles and milk production of female Saanen goats belonging to different genetic groups raised in the semi-arid region of Rio Grande do Norte in Northeast Brazil. The study was conducted in the city of Lages (5° 42 00 S and 36° 14 41 W). We used 25 lactating female Saanen goats, distributed into 3 genetic groups: 5 purebred animals, 11 three-quarter bred and 9 half-bred. Behavioral observations were made over three consecutive days in the months of August and September, between 09:00 and 11:30h, when the animals were grazing. Physiological and meteorological data were recorded in the last three days of June, July, August and September at 05:00h and at 16:00h. In the semi-intensive breeding system, the animals from different genetic groups were similar in both field behavior and physiological response patterns. Although the purebred goats had longer hair, they did not show symptoms of thermal discomfort. Their white hair helped to reflect the short wavelength rays and thus eliminate those at the longer wave lengths. We concluded that the animals raised in the semi-intensive milk production system in this study seem to have adapted to the climatic conditions of the semi-arid region of Rio Grande do Norte, Brazil

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Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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O aumento significativo da produção de milho na segunda safra no Brasil, principalmente no centro-sul do país, têm estimulado os programas de melhoramento da cultura a selecionar genótipos que sejam adaptáveis às condições climáticas das diferentes épocas de semeadura. Nesse sentido, o objetivo do presente trabalho foi quantificar a interação progênies x épocas de semeadura e verificar seus reflexos no progresso genético com o uso de índice de seleção multivariado para seleção de progênies do Composto Isanão VF-1 de milho. As semeaduras foram realizadas na segunda safra em 2004 e na primeira safra do ano agrícola 2004/05. Foram utilizadas 71 progênies de meios irmãos avaliadas em blocos ao acaso, com três repetições. Os caracteres avaliados foram: altura de plantas, altura de espigas, tombamento, prolificidade e rendimento de grãos. Realizaram-se a decomposição da interação progênies x épocas e foram estimados os ganhos pelo índice de seleção descrito por Mulamba e Mock. Houve predomínio da interação do tipo simples para maioria dos caracteres, exceto para prolificidade, que revelou 86% de interação do tipo complexa. Pelo índice de Mulamba e Mock, os ganhos proporcionais mais adequados para o conjunto de caracteres avaliados foi obtido pelos pesos econômicos atribuídos por tentativas. Os ganhos preditos foram de 1,41, 0,86, -13,03, 9,54 e 16,12% para altura de planta, altura de espiga, tombamento, prolificidade e rendimento de grãos, respectivamente.

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Período seco e temperaturas amenas são condições climáticas ideais durante a maturação e colheita de sementes de soja. O objetivo foi verificar o efeito da irrigação no período pós-maturidade fisiológica, sobre o potencial fisiológico de sementes de soja semeadas no inverno. A disposição dos tratamentos seguiu esquema fatorial envolvendo três cultivares (IAC-19, Conquista e IAC 8-2) e duas épocas de interrupção da irrigação (início do estádio R7 e irrigação até 14 dias após R8). Foram feitas amostragens (colheitas) no início do estádio R7, 3, 7, 10, 14 (estádio R8) e 28 dias após o início do estádio R7. Para as avaliações utilizaram-se os testes de germinação, de envelhecimento acelerado e de condutividade elétrica e determinou-se a porcentagem de sementes manchadas e defeituosas. Nas condições em que foi realizado o experimento, concluiu-se que a irrigação após o estádio R7 não compromete e pode até melhorar o potencial fisiológico das sementes produzidas; a produção de sementes de soja em semeadura de inverno é possível em função de condições climáticas favoráveis.

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Water scarcity is a reality for the inhabitants of the Brazilian semiarid region. The problem, in quantitative terms , is caused due to local climatic conditions due mostly to a water deficit. Qualitatively, results of multiple uses and resulting contamination by human activities. Eutrophication is presented as a threat to the sustainable use of water resources, in order to favor the predominance of dense populations of cyanobacteria, which can be potentially harmful to human health. The aim of this study is to understand the population dynamics of phytoplankton and cyanobacteria to assess water quality of reservoirs Santa Cruz do Apodi and Pau dos Ferros belonging to bacia Apodi Mossoró-RN . Water samples were collected monthly between October 2011 and May 2012 in reservoirs Santa Cruz do Apodi and Pau dos Ferros, in this latter , in Jan/12 we performed a diel profile . The abiotic variables obtained in the field and in the laboratory were: water temperature , dissolved oxygen , pH , turbidity , transparency , total nitrogen and total phosphorus . Phytoplankton samples were collected with a plankton net and bottle of Van dorn . Were performed : identification , quantification , calculation of biovolume , classification into functional groups and index calculation phytoplankton assembly ( Q ) , cyanotoxins were quantified by ELISA . Statistical analyzes supported the evaluation of the dynamics between biotic and abiotic factors. A questionnaire was conducted to examine the conceptions of the population, education professionals and students. The reservoir of Pau dos Ferros, shallow , turbid and eutrophic showed dominance of the functional group SN throughout the sample period . The phytoplankton biomass ranged from 20 to 70 mm ³ . L - 1, the lowest values coincided with the increase of the mixing zone and transparency, which contributed to the occurrence of a change in species composition phytoplankton . The application of the index Q proved relevant, the reservoir of Pau dos Ferros , depending on the species present , was classified ecologically as bad for almost the entire sample period . The reservoir Santa Cruz do Apodi showed low biomass ( 0.04 and 4.31 mm ³ . L - 1 ) and greater diversity in the phytoplankton composition . According to the index assembly (Q ), it showed moderate condition during most of the period influenced by different functional groups of typical meso- eutrophic environment (K S0, H1, C, F , J , E, D and N) . Associations of diatoms and green algae D and X1 succeeded populations of cyanobacteria in periods marked by greater instability in the system , caused by wind or rain. In summary , the occurrence of drought has a direct influence on the hydrological conditions of the reservoirs , in general, these events, reducing the reservoir level is directly related to decreased water quality and increased density of phytoplankton occurring predominance of cyanobacteria , the index Q reflected well to changes in phytoplankton composition , being a good indicator for biomonitoring of reservoirs in this study and survey of previous conceptions showed the need to work on environmental awareness for the preservation of water resources by conducting workshops for Environmental Education