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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Los copépodos cyclopoida de diferentes ambientes acuáticos en la concesión para la conservación Río Los Amigos, Madre de Dios, Perú

López Paría, Diana Mabel January 2015 (has links)
Existe un completo desconocimiento de la riqueza de copépodos ciclopoides en los cuerpos de agua de la amazonía peruana y particularmente en Madre de Dios. En este departamento, la actividad minera es la principal estrategia de subsistencia y de desarrollo económico, y la intensidad con que se realiza ha conllevado a prácticas ambientalmente irresponsables que están afectando todo el ecosistema y, por ende, la riqueza de componentes planctónicos, como los copépodos ciclopoides, que aún no han sido estudiados. La Concesión para la Conservación de la Cuenca Amazónica (ACCA) en el río Los Amigos ubicada entre la intersección de las cuencas del río Madre de Dios y Los Amigos, es zona de amortiguamiento del Parque Nacional Manu. Esta área posee una gran diversidad de ambientes acuáticos, (quebradas, cochas y aguajales), de tipo de agua negra y blanca. En el 2006 se colectaron muestras de plancton para identificar y determinar los taxa de ciclopoides, tipificar los ambientes según la composición de especies e índice de constancia, relacionar parámetros de oxigeno disuelto, temperatura, pH y dióxido de carbono con la riqueza y determinar si existe similaridad entre las quebradas, cochas y aguajales. Se registraron por primera vez 34 especies para Madre de Dios y la Amazonia peruana; y 4 géneros para el Perú. Considerando los registros publicados para los Andes en 1989, se incrementó con este estudio 28 especies, siendo el total actual de 49 especies de ciclopoides para el Perú. La única especie constante en los tres ambientes acuaticos fue Ectocyclops herbsti, a nivel de composición si se identificaron especies que no se presentaban en uno u otro ambiente y cuando se intento relacionar con parámetros físico-químicos no se halló relación con la riqueza. Las especies características para las quebradas, fueron Ectocyclops herbsti, Macrocyclops albidus albidus y Tropocyclops schubarti, para las cochas, Microcyclops ceibaensis, M. finitimus y E. herbsti, y para los aguajales, Ectocyclops herbsti y Tropocyclops schubarti. No se observó una agrupación de composición de especies entre quebradas, cochas y aguajales; sin embargo, fue evidente un patrón espacial de especies coincidente con la distribución de las estaciones relacionado probablemente con el origen y conexión del agua que llega a esos ambientes. Palabras clave: ciclopoides, agua blanca, agua negra, riqueza, amazonia peruana. / --- There is a complete lack of information about the richness of cyclopoid copepods in wáter bodies of the Peruvian Amazon, particularly in Madre de Dios. In this department, mining is the main strategy for subsistence and economic development, and the intensity with which it is done has led to environmentally irresponsible practices that are affecting the entire ecosystem and, therefore, the wealth of planktonic components such as cyclopoid copepods, which have not yet been studied. The Association for the Amazon Basin Conservation (ACCA) in Los Amigos River, located between the intersection of the basins of Madre de Dios River and Los Amigos River, is a buffer zone for Manu National Park. This area has a great diversity of aquatic environments (streams, lakes, and palm swamps) of blackwaters and whitewaters. Plankton samples were collected in 2006, in order to identify and determine cyclopoid taxa, characterize habitats by species composition and constancy index, relate parameters of dissolved oxygen, temperature, pH and carbón dioxide with richness and determine if there is similarity between streams, oak lakes and palm swamps. The results of this study reported 34 new species for Madre de Dios and the Peruvian Amazon; including 4 new genera for Peru. Considering the published records for the Andes in 1989, the present work increased the last record by 28 new species, with a current total of 49 species of cyclopoids for Peru. The only common species in all three aquatic environments was Ectocyclops herbsti. In terms of composition, some species were identified as being absent in one or two environments, and when attempted to relate with physicochemical parameters, it weren’t found any relationship with richness. The characteristic species for stream were Ectocyclops herbsti, Macrocyclops albidus albidus and Tropocyclops schubarti; for oak lakes, Microcyclops ceibaensis, M. finitimus and E. herbsti; and for palm swamps, Ectocyclops herbsti and Tropocyclops schubarti. No grouping of species composition among streams, oak lakes, and palm swamps were observed; however, a spatial pattern of species coincident with the stations distribution was found, probably related to the origin and connection of water reaching those environments. Keywords: cyclopoids, whitewater, blackwater, richness, Peruvian Amazon.
2

Considerations for developing a sustainable agriculture research and education centre at Agua Blanca, El Salvador

Smith, Bradley Jefferson 13 January 2011 (has links)
This SSHRC and Pacific Leaders funded thesis summarizes participatory action research conducted in El Salvador between January 2008 and April 2009. This research resulted in a $355,000 proposal to the Canadian International Development Agency for a sustainable agriculture research and education centre in canton Agua Blanca, Morazán, El Salvador. The project is proposed by Canadian NGO, Rainbow of Hope for Children, in partnership with Salvadoran NGO, Fundahmer. Fundahmer owns 9.8 hectares of land in Agua Blanca. The researcher analysed practices at an existing Rainbow agriculture project in Izalco, and identified options for Agua Blanca by defining project goals and objectives, conducting a risk assessment, describing proposed centre activities, quantifying beneficiaries, assessing funding requirements, and developing performance measures. Funding was rejected, citing six sections that required additional information for second submission: sector and regional context, sustainability, gender, beneficiaries, performance measures, and environmental impacts. Seven recommendations are included to move project forward.
3

Constraining the Geometry and Evolution of the Maneadero Basin, Baja California, Mexico

Callihan, Sean 11 February 2010 (has links)
The Maneadero Basin is identified as a transtensional sedimentary basin along the Agua Blanca Fault (ABF) in the southern limit to the "Big Bend" Domain of the North American-Pacific plate boundary zone. The ABF exhibits both the dextral and normal components of slip. This creates an interesting setting for the formation of the Maneadero Basin because structures with orientations similar to the ABF are typically contractional (e.g.: Puente Hills Fault, Whittier Fault, and Rancho Cucamonga Fault). The question if this basin is evidence of plate-scale transtension or local extension associated with bends/stopovers along the ABF is addressed by this study with three working hypotheses. The hypotheses presented by this study are: 1) the basins formed by a dip-slip component on the ABF and truly are an expression of regional transtension, 2) the basins formed at right steps along the dextral ABF, or 3) the basins formed as a result of juxtaposing basement blocks with disparate topographies. Each of these hypotheses would produce unique basin geometries and structures within and around the Maneadero Basin. To test these aforementioned hypotheses, a multi-disciplined study was conducted in the basin. A structural dataset was collected to identify kinematics and offsets of faults both within and bounding the basin. A gravity survey was also conducted to image the basin geometry. The results of the study show an asymmetrical gravity anomaly that closely follows the trace of the ABF. The amplitude of the anomaly is 54 mGal, the gradient of which is steepest around the ABF and shallows away from the fault to the north and east. Forward models of this anomaly indicate the ABF is a steeply north dipping fault. The gravity anomaly also indicates that the deepest part of the basin is located close to, but not coincident with the ABF and the basin gradually shallows to the northeast. This geometry is consistent with the hypothesis that the basin results from dip-slip on the ABF. This idea is also supported by the structural data, which includes fluvial terraces that have been uplifted and offset by faulting on the ABF, and by the presence of a normal fault on the ABF in the center of the basin. The third hypothesis is also supported by models of the gravity data, which suggest a deep (~900m) bowl shaped erosional feature in the bedrock. Dextral slip on the ABF juxtaposes the topographically high Punta Banda Ridge with this topographically low feature. Overall, the data presented in this study suggest the formation of the Maneadero Basin results from is a combination of the dip-slip component on the ABF and juxtaposition of the topographically elevated Punta Banda Ridge with a topographically lower basin of Bahia Todo Santos and Valle Maneadero. Geodetic data strongly suggest that the difference in motion of the Baja Microplate (south of the ABF) to the disrupted southern California Block (north of the ABF), and the orientation of the ABF relative to that motion, is causing transtension in the Maneadero Basin. This combined with strike-slip juxtaposition of different topographies allowed for the formation and evolution of the Maneadero Basin.
4

Petrographic and Kinematic Investigation of the Volcaniclastic and Plutonic Rocks of the Northern Alisitos Arc, Baja California, Mexico

Tutak, Fatin 19 February 2008 (has links)
The Alisitos arc segment forms part of the western zone of Jura-Cretaceous Peninsular Ranges batholith of Baja California. It extends south from the ancestral Agua Blanca Fault to the state boundary between Baja Norte and Sur. The study area is located within a fold and thrust belt intruded by a number of plutons that were emplaced during and after the deformational event. The northern end of the Alisitos arc is characterized by subvertical tight to isoclinal folds and high-angle reverse faults that define a northwest trending, southwest vergent fold and thrust belt. The aABF defines the northern limit to the Alisitos arc segment. In this study we present the results of a petrographic study of igneous rocks in order to determine the relative timing and the distribution of deformation within the northern Alisitos arc segment. The study includes samples of the mylonitic shear zone of the aABF, and plutonic samples from intrusions proximal to the aABF emplaced later during regional deformation. These samples were investigated in order to characterize the distribution of the subsolidus strain in grain scale and the sense of shear during later phases of deformation in the northern Alisitos arc. The results are presented and discussed based on the mineralogical and textural observations from the Balbuena pluton, the Piedra Rodada pluton, and volcaniclastics that were deformed within the aABF. The Balbuena pluton, emplaced at ~ 108 Ma after the surrounding country rocks had already been folded, exhibits little if any evidence for subsolidus deformation. In contrast, the Piedra Rodada pluton, emplaced at ~ 105 Ma just to the southwest of the aABF, exhibits a strong magmatic fabric overprinted by a moderate subsolidus fabric to the southwest that grades into a strong subsolidus fabric with proximity to the fault. Kinematics observed from lineation parallel-foliation normal sections exhibit consistent top-to-the southwest sense of shear.

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