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1.
Braz. arch. biol. technol ; 63(spe): e20190520, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1142513

RESUMEN

Abstract Conservation agriculture practices can contribute to changes in soil nutrient dynamics over time. This experiment evaluated the changes in total stocks and distribution of carbon, nitrogen, phosphorus and sulfur concentrations in soil, during 60 months, in an integrated crop-livestock system (ICLS) due to anticipated fertilization of sources and doses phosphates applied in soil surface. The experiment was conducted over a period of five years, under Typic Dystrudept, using a randomized block design, in an incomplete factorial scheme (3×3+1), with four replications. Treatments consisted of three sources of P [triple superphosphate (TSP), rock phosphate - Arad (RP) and magnesium thermophosphate (MTP)], along with four doses of P (0, 60, 120 and 180 kg ha-1 P2O5 total). Samples of soil were collected in 0-5, 5-10, 10-15, 15-20 and 20-30 cm layers at 24, 36, 48 and 60 months after beggining of experiment where the following chemical attributes were evaluated: (i) total organic carbon (TOC); (ii) total nitrogen Kjeldahl (TNK); (iii) available P by ion exchange resin method (P-IER); and (iv) available S-SO4 2-. The ICLS conditions provided increased total stocks and concentrations of TOC, TNK, P-IER and S-SO4 2- over time. The applications of different phosphates had no influence on soil TOC concentrations during the five years of experimentation. The concentrations of TNK, P-IER and S-SO4 2- showed an increase in different layers of soil, with the application of sources and doses of P. The P fertilization practice that was anticipated can consist of an efficient management of soil fertility, using properly managed conservation systems.


Asunto(s)
Humanos , Animales , Fosfatos/administración & dosificación , Suelo/química , Producción de Cultivos , Análisis del Suelo , Fertilizantes , Crianza de Animales Domésticos , Fósforo/análisis , Azufre/análisis , Carbono/análisis , Nitrógeno/análisis
2.
Artículo en Inglés | IMSEAR | ID: sea-114060

RESUMEN

Decomposition rates and nutrient contents of sulphitation pressmud (SPM), either alone or by mixing with cow dung and rice straw, under the aerobic (heap and NADEP), anaerobic (pit) and vermicomposting methods were compared. Loss in Organic C and C/N ratios of the decomposing materials indicated the heap and NADEP methods faster for the composting of SPM alone and SPM + cow dung and vermicomposting method for SPM + rice straw registering significant reductions in Organic C ranging from 45.0 to 61.0% from the respective decomposing materials at termination time (119 days). The heap and NADEP methods recorded C/N ratio of SPM alone as low as 11 and 12 and SPM + cow dung as 12.0 and 13.9 at termination stage. Vermicomposting method brought the C/N ratio of SPM + rice straw to 16.4 as compared to 18.6 to 29.8 with the other methods. Irrespective of the composting methods, CO2 evolution from the decomposing materials was higher in early period (up to 28 days). Among methods, NADEP and heap methods recorded more CO2 evolution in early period while vermicomposting method showed more CO2 evolution at the later intervals in comparison to the other methods. Nutrient content in the decomposing materials at different intervals depended on their initial contents. Total N in the composts were statistically comparable, however, the composts of SPM alone recorded relatively more N than SPM + cow dung and SPM + rice-straw prepared by the respective methods. Total P and K contents of the composts increased with time irrespective of the composting methods. Composts of SPM alone recorded significantly more total P than SPM + cow dung and SPM + rice straw at 62, 91 and 119 days while SPM + rice straw recorded more total K than the composts of other materials. Total P in the composts did not differ with the composting methods, but total K in composts of SPM alone was relatively more with heap and NADEP methods, in SPM + cow dung with pit method and in SPM + rice straw by vermicomposting method. Total S in the composts decreased with time and both the aerobic methods showed more reductions than pit and vermicomposting methods.


Asunto(s)
Agricultura , Animales , Biodegradación Ambiental , Carbono/análisis , Dióxido de Carbono/química , Fertilizantes , Residuos Industriales , Estiércol , Nitrógeno/análisis , Oryza , Eliminación de Residuos , Aguas del Alcantarillado , Suelo , Azufre/análisis , Administración de Residuos
3.
Artículo en Inglés | IMSEAR | ID: sea-114095

RESUMEN

Chemical composition of the aerosols is an important aspect of aerosol monitoring. The adverse effects on human heath due to different elements in aerosols depend on their concentrations. A comparative study of aerosol concentration and composition from an industrial town Mandi-Gobindgarh and a nearby (25 km away) non-industrial and comparatively less polluted town Morinda, in state Punjab (India) was carried out. Aerosol samples were analyzed by Particle Induced X-ray Emission (PIXE) technique at the Institute of Physics, Bhubaneshwar. Elemental concentrations were found to be much higher in Mandi-Gobindgarh as compared to Morinda. However, the large deviations from the mean concentrations, particularly in Mandi-Gobindgarh is suggestive of highly varying day to day industrial activity and changing weather conditions. Elements such as S, Br and Pb were found higher in the PM2.5 (particulate matter with = 2.5 microm aerodynamic diameter), which are related to burning of coal and oil in furnaces in Mandi-Gobindgarh. The elements related to natural dust such as K, Ca, Ti, Mn, and Fe are mainly distributed in PMcf (particulate matter with aerodynamic diameter between 2.5 and 10 microm) fraction in both the towns. High concentrations of Ti, Cr, Mn, Fe and Zn in the PMcf fraction from Mandi-Gobindgarh are likely due to the industrial activity of Steel rolling mills.


Asunto(s)
Aerosoles , Contaminantes Atmosféricos/análisis , Arsénico/análisis , Bromo/análisis , Cloro/análisis , Monitoreo del Ambiente , India , Industrias , Metales/análisis , Espectrometría por Rayos X , Azufre/análisis
4.
Rev. colomb. biotecnol ; 7(1): 15-24, jul. 2005. ilus, tab, graf
Artículo en Español | LILACS | ID: lil-606117

RESUMEN

El principal inconveniente en la combustión de los hidrocarburos es la conversión del azufre y el nitrógeno a sus respectivos óxidos, los cuales participan en la formación de lluvia acida y deterioran el medio ambiente e infraestructuras. La remoción de azufre a partir de compuestos órgano-azufrados mediante el uso de microorganismos ha surgido como una alternativa frente al proceso catalítico de hidrodesulfurización (HDS). En el presente trabajo se evaluó la actividad desulfurizadora de veintitrés aislados nativos de Pseudomonas spp. sobre dibenzotiofeno (DBT), usando un sistema de fermentación con igual proporción de fase acuosa y orgánica (n-hexano) en presencia de oleato de etanolamina. Los aislados 02,05 y 06 conservaron su viabilidad en este medio y presentaron una remoción de azufre entre 6,0 y 9,4%, generando los metabolitos DBT-sulfona, DBT-sulfóxido, 2-hidroxibifenilo (2-HBP) y sulfato presentes en la ruta metabólica 4S. Con estos aislados se evaluó la actividad desulfurizadora sobre keroseno y se observó una remoción de azufre entre 19,9 y 62,6% y una disminución del poder calorífico entre 0,45 y 5,55%.


The main difficulty with fossil fuel combustión lies in sulphur and nitrogen becoming converted to their respective oxides, forming part of the acid rain which deteriorates the environment and infrastructure. Removing sulphur from organo-sulfur compounds by using micro-organisms has become an alternative to hydrodesulphurisation (HDS). Twenty-three Pseudomonas spp. native strains' desulphurisation activity on dibenzothiophene (DBT) was evaluated by using a fermentation system having equal proportions of aqueous and organic (n-hexane) phases in the presence of ethanolamine oléate. The 02, 05 and 06 strains maintained their viability in this médium, presenting 6,0% to 9,4% sulphur removal, producing DBT-sulphone, DBT-sulphoxide, 2-hydroxybiphenyl (2-HBP) metabolites and sulphate belonging to the 4S pathway. These native strains' desulphurisation activity was evaluated on kerosene, presenting 19,9% to 62,2% sulphur removal having 0,45% to 5,55% calorific power loss.


Asunto(s)
Azufre/análisis , Azufre/clasificación , Azufre/efectos adversos , Pseudomonas/clasificación , Pseudomonas/química , Queroseno/análisis , Queroseno/clasificación , Queroseno/microbiología , Hidrocarburos Cíclicos
5.
J Environ Biol ; 2004 Oct; 25(4): 423-9
Artículo en Inglés | IMSEAR | ID: sea-113946

RESUMEN

This study was carried out to determine the possible effects of the Afsin-Elbistan Coal Power Plant (AECPP) on the environment.. The soil and plant samples were collected, based on the dominant wind direction, which is from northeast to southwest and we defined the northeast part of the plant as the less contaminated direction (LCD) and the southwest part as the more contaminated direction (MCD). The results indicated that the AECPP created environmental problems and caused contaminations especially in the MCD. The results of the statistical analysis for the measured attributes between the LCD and the MCD showed that there were significant differences for pH, SO4(-2)-S, Ni and Pb. Significant correlations were found between the distance from the AECPP and some of the measured soil and plant parameters in the MCD. The concentrations of SO4(-2)-S, Ni and Pb decreased as the distance increased. The discharge water carries a potential risk for the aquatic life and soil health in the area. The honey quality was also affected negatively by fly ash and emission.


Asunto(s)
Carbono/análisis , Carbón Mineral , Ambiente , Monitoreo del Ambiente/estadística & datos numéricos , Miel/análisis , Concentración de Iones de Hidrógeno , Metales Pesados/análisis , Material Particulado , Plantas/química , Centrales Eléctricas , Sodio/análisis , Suelo/análisis , Azufre/análisis , Turquía , Contaminantes Químicos del Agua/análisis
6.
Rev. chil. anat ; 15(2): 115-9, 1997. ilus, tab
Artículo en Inglés | LILACS | ID: lil-211914

RESUMEN

Mediante la técnica del microanálisis de rayos X, se investigó la cantidad y distribución del azufre en la zona pelúcida de los ovocitos de ratón, hamster y conejo. La cantidad de azufre varía entre 2853 y 10178 mmol/Kg de peso seco. La cantidad más alta de azufre se encontró en los ovocitos de hamster y la más baja en los ovocitos de conejo; siendo la cantidad encontrada en los ovocitos de ratón, intermedia entre ambas. Se detectó una disminución gradual del azufre desde la región interna hacia la región externa de la zona pelúcida, en los ovocitos de ratón y conejo. Esto es coincidente con las asimetrías morfológica y/o bioquímica descritas para la zona pelúcida de estas especies. Aunque se han descrito asimetrías bioquímica y funcional en la zona pelúcida de los ovocitos de hamster, en el presente análisis no se detectó una distribución asimétrica del azufre. Sin embargo, resultó evidente una estratificación de este elemento en la zona pelúcida de los ovocitos de hamster


Asunto(s)
Animales , Conejos , Ratones , Cricetinae , Oocitos/química , Azufre/análisis , Zona Pelúcida/química , Cricetinae/embriología , Ratones/embriología , Conejos/embriología
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