خيارات البحث
النتائج 501 - 510 من 2,330
ESTRUTURA E DISTRIBUIÇÃO ESPACIAL DE Mimosa tenuiflora (Willd.) Poir. EM DOIS FRAGMENTOS DE CAATINGA EM PERNAMBUCO
2011
JOÃO TAVARES CALIXTO JÚNIOR | MARCOS ANTÔNIO DRUMOND | FRANCISCO TARCÍSIO ALVES JÚNIOR
Mimosa tenuiflora (Willd.) (jurema preta) is a xerophytic species of the shrub-arboreal habit, indicative of secondary succession stage of recovery or progressive, widely disseminated by different caatinga physiognomies of northeastern Brazil, bringing great potential. For the few studies that address their environmental performance, this study aimed to investigate structural and ecological aspects of its population, based data in diameter and height, and characterize the spatial distribution pattern of this species in the study areas. The phytosociological survey was conducted in two areas with 2 and 80 hectares of caatinga at the Experimental Station of Embrapa Semiarid, Petrolina - PE. 10 units were plotted on a random sample measuring 8.0 x 40m, and included all individuals living in diameter at soil level K 3 cm, and measured the total height of the same. Were sampled 283 and 61 individuals in 100 and 80% of plots in areas I and II respectively, inserted mostly in the first diameter classes (3.0 - 6.0 cm and 6.1 - 9.0 cm) and height (2.0 - 3.0 m and 3.1 - 4 m), without trend to standard reverse-J-shape in areas. The spatial distribution, measured by the Payandeh index, reached a value of 2.4 in area I and 7.8 in area II, indicating that the species has a aggregated distribution in both areas. The calculated values for the of Liocourt quotient in areas I and II respectively, got an average of 0.67 and 1.12 with great variation, showing unbalance, despite being in progressive process of natural regeneration.
اظهر المزيد [+] اقل [-]CRESCIMENTO E PRODUTIVIDADE DE SEMENTE DE MAMONA TRATADA COM LODO DE ESGOTO
2011
ALTINA LACERDA NASCIMENTO | REGYNALDO ARRUDA SAMPAIO | DELACYR DA SILVA BRANDÃO JÚNIOR | GERALDO RIBEIRO ZUBA JUNIO | LUIZ ARNALDO FERNANDES
Sewage sludge, waste from the stations of wastewater treatment, has high contents of organic matter and nutrients and, when stabilized, it presents enormous potential for agricultural use. This study aimed to evaluate the effect of doses of sewage sludge on growth and yield of castor bean. The experiment was conducted in Cambisol, using the cultivar Guarany AL 2002. The treatments in a randomized block design with four replicates, corresponding to a treatment with chemical fertilizer (90 kg ha-1 of P2O5 and 30 kg ha-1 K2O at planting and 40 kg.ha-1 N, 40 days after planting), and five doses of dry sewage sludge (0, 15, 30, 45 and 60 t ha-1). At the end of the cycle, the assessments were made of stem diameter, plant height and productivity. The productivity of seeds and the biometric characteristics of castor bean increased with increasing doses of sewage sludge applied to soil, and the dose from 15 t ha-1 is sufficient for replacement of mineral fertilization of culture without the risk of soil contamination with heavy metals.
اظهر المزيد [+] اقل [-]USE OF REJECT BRINE FROM DESALINATION ON DIFFERENT DEVELOPMENT STAGES OF HYDROPONIC LETTUCE
2011
NILDO DA SILVA DIAS | FRANCISCO AÉCIO DE LIMA | CLÁUDIO RICARDO DA SILVA | OSVALDO NOGUEIRA DE SOUSA NETO | HANS RAJ GHEYI
In order to evaluated the impact of the high salinity reject brine from reverse osmosis desalination on hydroponics lettuce cultivated in greenhouse an investigation was carried out in Mossoro, Northeast of Brazil (5º11'S, 37º20'O and 18m above sea). Two lettuce cultivars ('Verônica' and 'Babá de verão') were cultivated with a basic nutrient solution with 1.1 dS m-1 (control) during the crop cycle (1-28 days after transplanting - DAT) - T0 and with basic nutrient solution containing 50% of the reject water from desalinization with 4.8 dS m-1 exposed during 1-7, 21-28, 7-14 e 1-28 DAT (T1, T2, T3 and T4, respectively). The addition of 50% of brine reject from desalination into the hydroponic nutrient solution allows grow only 'Verônica' lettuce with no reduction in fresh biomass. This lettuce cultivar shows to be more tolerant to salinity for all exposure time with reject brine in the nutrition solution, despite the fact that 'Babá de Verão' cultivar is more productive.
اظهر المزيد [+] اقل [-]SIMILARIDADE DAS VARIÁVEIS HIDROQUÍMICAS COM O USO DA ANÁLISE MULTIVARIADA, NA BACIA DO SALGADO, CEARÁ
2011
EVELINE VIANA SALGADO | EUNICE MAIA DE ANDRADE | SÁVIO DE BRITO FONTENELE | ANA CÉLIA MAIA MEIRELES
This study aimed to identify the similarities among hydrochemical variables describing the groundwater qualities in the Salgado watershed river (Southern Ceará), with the use of multivariate statistical analysis. Also, the groundwater hydrochemistry was investigated and classified using the Piper diagram. The study was developed from secondary data provided by the CPRM (Centro de Estudo Geológico do Brasil, previously Companhia de Pesquisa de Recursos Minerais). The geological formation of the Salgado basin has two aquifer systems, one on sedimentary rock (porous, karst and alluvial) and another on (fractured) crystalline rock. The research was conducted in 24 groundwater wells spread out over the drainage area of the basin, with data having been collected for the last 10 years. The water samples were analyzed for their content of Na+, K+, Ca2+, Mg2+, Cl-, CO3, HCO3 -, SO4 2- and CE. Two groups were formed by the use of cluster analysis, and both were independent with respect to their hydrological characteristics, and similar in hydro geological formation. The water quality study showed no temporal interference. The two components explained 78.30% of the total variance of the water quality. According to the Piper diagram, the waters were classified as 55.6% mixed chlorided water and 40% mixed bicarbonate water, in groups 1 and 2 respectively. The hydrochemical characterization of the studied waters implied no limitation to their human consumption.
اظهر المزيد [+] اقل [-]EFEITO DO NITRATO DE POTÁSSIO NA REDUÇÃO DO ESTRESSE SALINO NO MELOEIRO
2011
WALDEMAR PEREIRA DE ANDRADE JÚNIOR | FRANCISCO HEVILÁSIO FREIRE PEREIRA | OTONIEL BATISTA FERNANDES | ROBERTO CLEITON FERNANDES QUEIROGA | FÁBIO MARTINS DE QUEIROGA
This paper aimed to evaluated the effect of the use of potassium nitrate on the reduction of stress on the melon plants exposed to excess salt in the irrigation water. The experiment was carried out at the Centro de Ciências e Tecnologia Agroalimentar (CCTA/UFCG) Pombal-PB, from 19/09/2009 to 20/10/2009, using the hybrid melon 'Hales Best Jumbo'. The treatments consisted of two levels of of salinity of the irrigation water (0.3 and 5.0 dS m-1) and rates of N in the form of potassium nitrate (5.5; 6.25; 7.0 and 8.5g per plant). The experimental design was randomized blocks, on the factorial scheme 2x4, with four replications. The highest rates of photosynthesis, stomatic conductivity, transpiration, leaf area, total dry mass and the fruit yield per plant were observed on melon plants irrigated with low salinity water (0.3 dS m-1) compared to the ones with the high saline water (5.0 dS m-1), and on rates of N between 6.10 and 7.8g of N per plant for both levels of salinity. The supply of N in the form of potassium nitrate was effective on reducing the melon plant the stressing effect caused by the salinity of the irrigation water up to the rate of 6.85g of N per plant. On absolute terms we can affirm that the best performance of the melon plant was achieved with the rate of 7.0g of N per plan when irrigated with normal water and 6.25 of N per plant when irrigated with saline water.
اظهر المزيد [+] اقل [-]ESTUDO DA ESTABILIDADE MICROBIOLOGICA E FISICO-QUIMICA DE POLPA DE CUPUAÇU DESIDRATADA EM ESTUFA
2011
JULIANA DA SILVA DE ABREU MOREIRA | MARIA LUZENIRA DE SOUZA | SEBASTIAO ELVIRO DE ARAÚ- JO NETO | REGINALDO FERREIRA DA SILVA
The irregular offer of cupuaçu pulp in the harvest time, the high endable of the fruits and the form of conservation by freezing, are factors that cause difficulties in the offer of this product in the market of Rio Branco/AC. The purpose of this work was to dehydrate the cupuaçu pulp and evaluate the shelf life in a period of 90 days. The experiment was conducted in the Unity of Technology and Foods (UTAL) of Federal University of Acre (UFAC). Cupuaçu fruits came broked, despolped and sanitized. Portions of 300 g of pulp were submitted in the process of dehydration in oven with air circulation by a temperature of 60 °C for 46, 52 e 58 hours. After the dehydration, the samples were submitted to the following analysis titratable acidity, pH, totals solids soluble (oBrix), moisture determination, ascorbic acid and water activity (aw). The microbiologycal analysis involved of Salmonella, thermotholerant coliforms at 45 °C, mesophilic bacteria and yeasts and moulds, all for triplicats. The results showed significant effect of interaction between dehydration time and storage to variables ºBrix and ascorbic acid. The water activity and the pH kept stable during all the period of storage, while the level of ascorbic acid reduces by the dehydration time and storage. The dehydration of in natura cupuaçu pulp in conventional oven is a practicable method of conservation and storage for 90 days.
اظهر المزيد [+] اقل [-]CARACTERIZAÇÃO DOS SOLOS E ANÁLISE DO ESTÁGIO DE DEGRADAÇÃO EM GLEBAS EM DIFERENTES AGROSSISTEMAS
2010
RUY BORGES DA SILVA | ANTONIO CLEMENTINO DOS SANTOS | RUI BEZERRA BATISTA
The objective of present work was of classifying, consonant the Brazilian System, profiles of soils of ecosystems, as subsidies to evaluation of soil quality. The fieldwork was driven at the place Chã de Jardim, municipal district of Areia, PB, Brazil. They were open trenches, in different agrosystems - sabiá population (T1), of pinus (T2), and traditional cultivation-degraded area (T3), where they were made the description and it collects of soil materials for accomplishment of the chemical and physical analyses. The soils were classified in the Brazilian System of Classification of Soils. Being adopted an operational sequence, the profiles of respective areas were classified as: Entisol, Oxisol and Inceptisol In terms of quality of soil and starting from an arbitrated minimum indication, it was verified that profiles under pinus population and sabiá have position privileged in relation to degraded area. In spite of drop reservation of nutrients of profiles (dystrophic), the recycling in the soil under leguminous (T1) it is more efficient, since the reservation of nutrients in the Entisol is smallest among the compared sub superficiality.
اظهر المزيد [+] اقل [-]AVALIAÇÃO DE MÉTODOS DE EXTRAÇÃO DE SILÍCIO E FÓSFORO EM AMOSTRAS DE SOLOS
2010
MAYKOM FERREIRA INOCÊNCIO | ROBSON SANTOS GUTIERREZ | JOSÉ OSCAR NOVELINO
The aim of this study was to evaluate silicon (Si) and two phosphorus (P) extraction methods in "Latossolos" under corn and sorghum. The experiments were conducted in green-house, in a completely randomized, with corn for the 5x2x2 factorial arrangement, consisting of five P rates (0, 96, 192, 288 and 480 mg dm-3) in the absence and the presence of 300 mg dm-3 of slag in two "Latossolos" and four replicates, while for sorghum the experimental design was 5x2, and is used only one soil. The experimental plots were subjected to two incubation periods, the first with slag (only half of the plot) and then with lime. In the first experiment two plants were cultivated corn pot for 45 days and then ten plants of sorghum for 60. After the experiments took place the collection of plants being evaluated for plant height, stem diameter and dry weight of maize shoots and just shoot dry matter of sorghum, the levels of Si and P in samples soil and plants. The medium texture soil showed better correlations of Si and P. For the Olsen P method as both the Mehlich 1 had good correlation. Sorghum showed higher correlation coefficients than corn.
اظهر المزيد [+] اقل [-]QUANTO VALE AS SEMENTES DA CAATINGA? UMA PROPOSTA METODOLÓGICA
2010
FABIO DA SILVA DO ESPÍRITO SANTO | JOSÉ ALVES DE SIQUEIRA FILHO | JÚLIO CÉSAR FERREIRA DE MELO JÚNIOR | ELIEZER SANTURBANO GERVÁSIO | ABDINARDO MOREIRA BARRETO DE OLIVEIRA
The accelerated process of environmental degradation in the São Francisco Drainage Basin (BHSF) has generated a high demand for seeds destined to the production of plant propagules. However there is no information about the commercial value of the diaspores of forest species which occur in the BHSF. The objective of this study is to propose a system to evaluate the worthiness of the kilogram of seeds for 22 plant species of the Caatinga, based in the following parameters: geographic distribution, endemism, level of threat, functional group, processing, collection effort, classification of seeds and number of seeds per kilogram. Field studies were conducted in five municipalities of the the region of the central valley of the São Francisco River and on five islands located in the main channel of the São Francisco River, from August 2007 to September 2008. The prices calculated using our system varied from R$ 10.00 for Syagrus coronata Mart. Becc. (Arecaceae) and R$ 44.15 for Handroanthus spongiosus (Rizzini) S.O.Grose (Bignoniaceae). From a 50% cut percentage in a cluster multivariate analysis we identified the occurrence of three groups: a group with seeds of lesser commercial value (average value of R$ 18.80.Kg-1), a second group with intermediate commercial value (R$ 28.21.Kg-1) and a third group with seeds of higher commercial value (R$ 32.85.Kg-1). We hope that this study will contribute to the process of conservation and ecological restoration of Caatinga, and also to the improvement of the socio-economic conditions of the local population from the commercialization of these seeds.
اظهر المزيد [+] اقل [-]GERMINAÇÃO DE SEMENTES DE MACAMBIRA (Bromelia laciniosa Mart. ex Schult)
2010
ALEK SANDRO DUTRA | ELIZITA MARIA TEÓFILO | SEBASTIÃO MEDEIROS FILHO
Macambira is a bromélia used in the alimentation of man and domestic animals on Northeast of Brazilian, especially in times of drought. The study was conducted to evaluate at identifying breaking dormancy methods and verifying how temperature and light can affect germination of its seeds. In the first experiment, the seeds were treated the following treatments: immersion in acetone, in alcohol, to eter, hot water, wash in running water, dry cold and dry heat, aiming at breaking dormancy and control. Were determinate the percentage of germination, first count of germination, index of velocity of germination and the mean time of germination. In the second experiment, after treatment of immersion in acetone during 60 minutes, the seeds were germinated under the following conditions: continued light and 25 ºC constant; continued light and 30 ºC constant; continued light and 35 ºC constant; continued light and temperatures (35 ºC/8 h and 20 ºC/16 h); continued dark and 25 ºC constant; continued dark and 30 ºC constant; continued dark and 35 ºC constant; continued dark and temperatures (35 ºC/8 h and 20 ºC/16 h); alternation of light (dark/16 h and light/8 h) and temperature of 25 ºC constant; alternation of light (dark/16 h and light/8 h) and temperature of 30 ºC onstant; alternation of light (dark/16 h and light/8 h) and temperature of 35 ºC constant; alternation of light and temperature (dark/20 ºC/16 h and light/35 ºC/8 h) and alternation of light and temperature (dark/25 ºC/16 h and light/35 ºC/8 h). It follows that the immersion in acetone during 60 minutes was the treatment more efficient to promote the of vigor and germination of seeds. The seeds do not germinate in the light absence, behaving as fotoblásticas positive.
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