Informes (Agronomía)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/30470

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Mostrando 1 - 5 de 5

Le lapin. De la biologie à l’élevage [Reseña]
(2016) González Redondo, Pedro; Universidad de Sevilla. Departamento de Ciencias Agroforestales; Universidad de Sevilla. AGR-233: Tecnología de la Producción Animal
Cambios de uso del suelo en la costa de la provincia de Cádiz durante la segunda mitad del siglo XX (1956-2003)
(2008) Jordán López, Antonio; Martínez Zavala, Lorena María; González Peñaloza, Félix A.; Bellinfante Crocci, Nicolás; Universidad de Sevilla. Departamento de Cristalografía, Mineralogía y Química Agrícola
En el presente trabajo se discute la dinámica de los cambios de uso entre 1956 y 2003 en la franja costera de la provincia de Cádiz en relación con el desarrollo urbano, la población y otros factores. El análisis de los principales usos del terreno mediante un sistema de información geográfica muestra los efectos del desarrollo de la tecnología agrícola y las políticas regionales agrícolas o medioambientales, además de otros procesos como el desarrollo de proyectos de turismo de masas o la expansión urbana. Para estudiar los patrones de transformación e identificar causas potenciales de cambio se han determinado áreas de influencia de variables específicas (distancia a las carreteras, graveras/minas, embalses y asentamientos urbanos). Los cambios de uso más importantes en el área se deben al crecimiento y concentración de la población en las ciudades, el turismo costero, el desarrollo de infraestructuras como carreteras o embalses y las políticas agrícolas que promueven el cambio del secano tradicional por regadíos durante la segunda mitad del siglo XX. El incremento de la productividad debido a la transformación de secanos en regadíos no muestra gran relación con la capacidad de uso del suelo. Una parte de la expansión agrícola ha ocurrido sobre suelos marginales, probablemente a causa del incremento en el input tecnológico. La pérdida de suelo agrícola per capita en el área de estudio parece estar asociado a una mejora en las tecnologías agrícolas y la falta de relaciones entre la población y la producción agrícola local en un contexto globalizado.
Study of the goat production system and the quality of milk produced in the Sierra Norte of Seville (Spain)
(CIHEAM, 2001) Alcalde Aldea, María Jesús; Mena Guerrero, Yolanda; Delgado Pertíñez, Manuel; Guzmán, J.L.; Gousse, S.; Ramírez, E.; Caravaca Rodríguez, Francisco Pascual; Castel Genís, José María; Universidad de Sevilla. Departamento de Ciencias Agroforestales
The objective of this study is to determine the situation of semi-extensive goat farms in the Sierra Norte of Seville (Spain) related to the bacteriological and hygienic quality of the raw milk. Twenty percent of the farms in the district were characterized, covering aspects related mainly to the milking and hygienic management. The bacteria and somatic cell content of raw milk coming directly from the udder and from churns (first at the end of the milking and second few hours after milking), were monitorized for a period of nine months in 14 farms. Besides all the farms hold general sanitary norms, most of them do not carry out the general dairy herd recommendations for milking routine. It is observed that most germ contamination in milk occurred in the hours after milking (from 46,000 up to 267,000 germ/ml), always below the maximum allowed. Somatic cells in all farms with more than 50 goats are above 1,500,000 somatic cells/ml.
Review on Compost as an Inducer of Disease Suppression in Plants Grown in Soilless Culture
(Global Science Books, 2011) Avilés Guerrero, Manuel; Borrero Vega, Celia; Trillas, María Isabel; Universidad de Sevilla. Departamento de Ciencias Agroforestales
Evaluación de la Seguridad Alimentaria y Radiológica en la Aplicación del Fosfoyeso Como Enmienda de Suelos Agrícolas en las Marismas del Guadalquivir
(2006) Abril Hernández, José María; García León, Manuel; García-Tenorio García-Balmaseda, Rafael; Delgado García, Antonio; Quintero Ariza, José Manuel; Periáñez Rodríguez, Raúl; Polvillo Polo, Oliva; Andreu Cáceres, Luis; Universidad de Sevilla. Departamento de Ciencias Agroforestales
The main goal of this Project has been the radiological and alimentary assessment of the agriculture use of phosphogypsum (PG), a by-product of the fertilizer industry, as Ca-amendment in reclaimed salt-marsh soils in SW Spain. The work-plan included: PG characterization (concentrations of radionuclide and heavy metals, 222Rn exhalation from PG stacks), experimental field studies attending to the effect of PG in agriculture soils and drainage waters, and studies on soil-to-plant transfer of radionuclides and heavy metals (through both, field and greenhouse studies). PG characterization (PG stacks) FERTIBERIA, a fertilizer factory located in Huelva (SW Spain) owns a non-active PG stack lying in the right bank of the Tinto River. From this PG stack, of about 1 km2 and 8-10 m deep, PG could be extracted for agriculture uses. PG has being traditionally used since late 1970’s as a Ca-amendment for the reclaimed soils from the salt-marsh area of the Guadalquivir River. 222Rn exhalation in this non-active stack has been measured following the USEPA method 115 (adapted for using cylindrical charcoal canisters). Experimental studies conducted in collaboration with the Institute of Biophysics from the University of Salzburg, demonstrated the repeatability and accuracy of the charcoal canister method for the commented determinations. The accuracy was demonstrated against the exhalation chamber method. Finally, experiments with PG columns of different heights demonstrated that the major contribution to Rn exhalation comes from the 0-50 cm horizon. A total of 162 measurements of 222Rn exhalation have been carried out, corresponding to 49 sampling points distributed through three different regions in the stack (1, compacted and dry top surface area; 2, loose –tilled- dry top surface and 3, sides). Three charcoal canisters were placed at each sampling point, covering an area of ~1 m2 . 222Rn exhalation values ( 510 ± 470, 250 ± 270 y 360 ± 170 Bq h-1 m-2 for regions 1,2, y 3, respectively) show high dispersion, but their mean values were under the USEPA limit of 2664 Bq h-1 m-2. Charcoal canister placed over big cracks and freshly removed surfaces did not reveal any significant change in 222Rn exhalation rates. The study of the normalized exhalation rates at different spatial scales (0.1, 0.75, 60 and 200 m) shows almost uniform standard deviations of ~0.5. The major contribution to this variability in the scale 0.1-1.0 m has to be attributable to the variability, at the same spatial scale, of the micro and meso-structure of pores and cracks. For larger spatial scales, changes in 226Ra concentration and percentage of humidity, contribute to the variability in the 222Rn exhalation rates. PG samples were taken at surface level (0-20 cm) in 20 sampling points, and at three different depths (0-30 cm, 30-60 cm and 60-90 cm) in another 20 sampling points. 226Ra was measured by liquid scintillation, providing activity concentrations of 720 ± 260 Bq kg-1 and 690 ± 180 Bq kg-1(dry weight), for regions 1 and 2, respectively. These values are over the threshold level of 370 Bq kg-1 established by the USEPA to allow the agriculture use of PG. 210Po activity concentrations (measured by alpha spectrometry) of 660 ± 160 Bq kg-1 y 575 ± 95 Bq kg-1 were determined for regions 1 and 2, respectively. U-isotopes were measured by alpha spectrometry, obtaining 238U activity concentrations of 170 ± 110 Bq kg-1 for region 1, and 160 ± 80 Bq kg-1 for region 2. The isotopic ratio 238U / 234U was 0.97 ± 0.03, as expected from secular equilibrium. 210Pb concentrations were measured by gamma spectrometry in few samples, and their values were closed to the corresponding values for 210Po activity concentrations. The above activity concentration for 226Ra and its daughters (and in less extend U-isotopes), are more than one order of magnitude higher that those found in agriculture soils from the area of Las Marismas of Lebrija. Multi-elemental analysis of the PG samples was carried out by ICP-MS technique following USEPA 200.8 method. PG samples, after oven-dried, disaggregated and sieved, were acid digested with supra-pure nitric acid in a microwave-oven (pseudo-total recovery). Cd concentrations were 2.0 g/g, one order of magnitude higher than those found in the agriculture soils from Lebrija. Thus, the Cd and the radionuclides from the 238U series will be the elements of major concern in the agriculture use of PG from FERTIBERIA stack. For the rest of the elements considered in the USEPA 200.8 method, concentrations were not too much higher than the corresponding ones for soils (Hg was not measured). Thus, taking into account the important dilution of PG when is applied as soil amendment (homogenised in the 0-30 cm soil horizon), the input of these elements has to be considered as quantitatively negligible. Nevertheless, all these elements has been considered in the present study, since the scientific literature reports some effects of the PG in the mobility and bioavailability of some metals in soils.

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