528 resultados para Bears.


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An integrated interpretation of the late Paleozoic structural and geochronological record of the Iberian Massif is presented and discussed under the perspective of a Gondwana-Laurussia collision giving way to the Variscan orogen. Compressional and extensional structures developed during the building of the Variscan orogenic crust of Iberia are linked together into major tectonic events operating at lithosphere scale. A review of the tectonometamorphic and magmatic evolution of the IberianMassif reveals backs and forths in the overall conver- gence between Gondwana and Laurussia during theamalgamation of Pangea in late Paleozoic times. Stages dom- inated by lithosphere compression are characterized by subduction, both oceanic and continental, development of magmatic arcs, (over- and under-) thrusting of continental lithosphere, and folding. Variscan convergence re- sulted in the eventual transference of a large allochthonous set of peri-Gondwanan terranes, the Iberian Allochthon, onto the Gondwana mainland. The Iberian Allochthon bears the imprint of previous interaction be- tween Gondwana and Laurussia, including their juxtaposition after the closure of the Rheic Ocean in Lower De- vonian times. Stages governed by lithosphere extension are featured by the opening of two short-lived oceanic basins that dissected previous Variscan orogenic crust, first in the Lower-Middle Devonian, following the closure of the Rheic Ocean, and then in the early Carboniferous, following the emplacement of the peri-Gondwanan allochthon. An additional, major intra-orogenic extensional event in the early-middle Carboniferous dismem- bered the Iberian Allochthon into individual thrust stacks separated by extensional faults and domes. Lateral tec- tonics played an important role through the Variscan orogenesis, especially during the creation of new tectonic blocks separated by intracontinental strike-slip shear zones in the late stages of continental convergence.

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La crisis de gobcrnabilidad de los recursos hídricos es clara y evidente en Costa Rica. Estos recursos están en proceso de deterioro y peligrosamente amenazados. En tan solo cinco décadas se pasó de la riqueza y abundancia de agua, a la vulnerabilidad y escasez de ésta. Un conjunto de realidades ha originado la mencionada crisis: la ausencia de políticas hídricas integrales, claras y estables, un marco legal desactualizado. estático y de mínimo cumplimiento, que ha permitido el uso ineficiente y la contaminación de los cuerpos de agua y desde luego la cultura dominante de poca o ninguna valoración del agua como recurso vital para el desarrollo presente y futuro de todas las especies que poblamos el país.La Agenda Ambiental del Agua en Costa Rica ha sido elaborada mediante un proceso parlicipativo. donde diversos actores sociales en diferentes regiones —Limón, Liberia y la Gran Area Metropolitana (GAM)— priorizaron los 10 principales problemas y sus potenciales soluciones:1) La educación formal e informal es muy débil respecto a como alcanzar el uso eficiente e inteligente de los recursos hrdricos. Igualmente, es débil para revertir el patrón de manejo de vertidos sin responsabilidad social.2) La excesiva centralización de las decisiones. Muy poca participación ciudadana tanto en la estructura organizativa como en la toma de decisiones.3) La inoperancia del marco institucional y legal —desconocimiento por parte de la sociedad civil de los procesos de denuncia y otros; la tramitología de denuncia es demasiado lenta e ineficiente, razón por la cual los denunciantes se cansan y desaniman—.4) La deficiente y casi nula valoración económica del agua, que tome en cuenta el manejo integral de las cuencas y la búsqueda de la permanencia del recurso en el futuro.5) La ausencia de planes hídricos de cuencas donde el plan regulador sea un componente básico.6) La desigual calidad del agua para los costarricenses según operador del servicio y región geográfica.7) La contaminación de aguas superficiales y subterráneas.8) La ausencia de conocimiento, socialización, sistematización y movilización en relación con el manejo del agua. Es necesario el aumento de las capacidades tanto técnicas y científicas como de cambio de cultura y conocimiento popular.9) Falta de información básica y mecanismos claros para poder utilizarla.10) La información existente en la actualidad se encuentra dispersa en diferentes orgarnza ciones y en algunos investigadores, lo que impide su uso efectivo.La Agenda Ambiental del Agua en Costa Rica aproxima los costos para la solución de los problemas apuntados anteriormente. Se necesita invertir alrededor de US$J .500 millones para abordar la gestión integrada de los recursos hídricos en el país.Abstract: The crisis of governance of thc watcr resources is clear and evideni in Costa Rica. These resources are in proccss oídeterioration anddangerously threatened. In only five decades it passed of che wealth and water abundance, to che vulnerability and shortagc of thc same one. A set of realities has originated dic mentioned crisis; dic abscncc of an integral, clear and siable water policy, a legal framework out of date. static one and of minimal fulfillmeni. which has allowed che inefficicrn use and ihe pollution ofihe water bodies. And certainly. hc dominecring culture of small ci no valuation to the water as vital resource for thc prcscnt and future dcvclopment of alI dic species. thai we populate che country.The Environmental Agenda of the Water in Costa Rica has bccn claborated by means of a participatory proccss. which includes several social actors in diverse regions —Limon. Liberia and Great Metropolitan Area (GAM) These actors prioritized lO principal problems related to water resources and thcir potential solutions:1) The formal and informal education is very weak with regard to since as reaches the efficient and intelligeni use of thc water resources. Equally. dic boss of managing is weak for revert of spilt without social responsibilicy.2) The excessive centralization of che decisions with very little civil parlicipation. both in the organizational siructure and in the decision making process.3) The un.workability of ihe institutional and legal framewoik —ignorance cii che pan of civil society of che proces.ses of denunciation and others the denunciation niechanism is ioo slow and inefticieni, a reason for which dic cbtmants get tired and discouragc—.4) Thedeficientone and almosi voideconomic valuationofthe waier. which bears in mmd the integral managing of the basin and dic scarc h of dic permancncy of dic resource to future.5) Thc absence of water plans of basin where dic regulatory plan is a basic component.6) The unequal quality of the water for dic Costa Ricans according tooperacor of dic service and geographica] region.7) The pollution of superficial and underground waters.8) The absence of knowledgc. socializ.arion, systematizing and mobilization in relation co the waier managing. Thc increase of dic capacities is necessary so much tcchnical and scicntific like of change of culture and popular knowledge.9) Lack of basic information and clear mechanisms to be able to use it.10) Thc cxisting information aL preseni is dispersed in different organizations and in sorne investigators, which prevents ihe effective use of the same one.The Environmental Agenda of the Water in Costa Rica brings the costs near for the solution of the pointed problems previously. Costa Rica needs to invest about US$1.500 million Lo approach ihe integrated managcment of the water resources in the country.

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In this work we compare Grapholita molesta Busck (Lepidoptera: Tortricidae) populations originated from Brazil, Chile, Spain, Italy and Greece using power spectral density and phylogenetic analysis to detect any similarities between the population macro- and the molecular micro-level. Log-transformed population data were normalized and AR(p) models were developed to generate for each case population time series of equal lengths. The time-frequency/scale properties of the population data were further analyzed using wavelet analysis to detect any population dynamics frequency changes and cluster the populations. Based on the power spectral of each population time series and the hierarchical clustering schemes, populations originated from Southern America (Brazil and Chile) exhibit similar rhythmic properties and are both closer related with populations originated from Greece. Populations from Spain and especially Italy, have higher distance by terms of periodic changes on their population dynamics. Moreover, the members within the same cluster share similar spectral information, therefore they are supposed to participate in the same temporally regulated population process. On the contrary, the phylogenetic approach revealed a less structured pattern that bears indications of panmixia, as the two clusters contain individuals from both Europe and South America. This preliminary outcome will be further assessed by incorporating more individuals and likely employed a second molecular marker.