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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

Sustaining Irrigation Agriculture for the Long-Term: Lessons on Maintaining Soil Quality from Ancient Agricultural Fields in the Phoenix Basin and on the North Coast of Peru

January 2013 (has links)
abstract: Irrigation agriculture has been heralded as the solution to feeding the world's growing population. To this end, irrigation agriculture is both extensifying and intensifying in arid regions across the world in an effort to create highly productive agricultural systems. Over one third of modern irrigated fields, however, show signs of serious soil degradation, including salinization and waterlogging, which threaten the productivity of these fields and the world's food supply. Surprisingly, little ecological data on agricultural soils have been collected to understand and address these problems. How, then, can expanding and intensifying modern irrigation systems remain agriculturally productive for the long-term? Archaeological case studies can provide critical insight into how irrigated agricultural systems may be sustainable for hundreds, if not thousands, of years. Irrigation systems in Mesopotamia, for example, have been cited consistently as a cautionary tale of the relationship between mismanaged irrigation systems and the collapse of civilizations, but little data expressly link how and why irrigation failed in the past. This dissertation presents much needed ecological data from two different regions of the world - the Phoenix Basin in southern Arizona and the Pampa de Chaparrí on the north coast of Peru - to explore how agricultural soils were affected by long-term irrigation in a variety of social and economic contexts, including the longevity and intensification of irrigation agriculture. Data from soils in prehispanic and historic agricultural fields indicate that despite long-lived and intensive irrigation farming, farmers in both regions created strategies to sustain large populations with irrigation agriculture for hundreds of years. In the Phoenix Basin, Hohokam and O'odham farmers relied on sedimentation from irrigation water to add necessary fine sediments and nutrients to otherwise poor desert soils. Similarly, on the Pampa, farmers relied on sedimentation in localized contexts, but also constructed fields with ridges and furrows to draw detrimental salts away from planting surfaces in the furrows on onto the ridges. These case studies are then compared to failing modern and ancient irrigated systems across the world to understand how the centralization of management may affect the long-term sustainability of irrigation agriculture. / Dissertation/Thesis / Ph.D. Anthropology 2013
2

Présence et identité Gallinazo dans la basse vallée de Santa, côte nord du Pérou

Choronzey, Jonathan January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
3

Présence et identité Gallinazo dans la basse vallée de Santa, côte nord du Pérou

Choronzey, Jonathan January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
4

La biodiversidad submarina de la costa norte del Perú / The marine biodiversity of the north coast of Peru

Casaretto Arbe, Luciana Maria 08 July 2021 (has links)
El objetivo general de la presente investigación es desarrollar una colección de trajes de baño femeninos a partir del análisis teórico y visual de la biodiversidad submarina de la costa norte del Perú. Además, para realizar la investigación teórica se plantearon los siguientes objetivos específicos: Explicar la biodiversidad submarina de la costa norte del Perú. Definir los conceptos principales de la biodiversidad submarina de la costa norte del Perú. Describir la situación de la biodiversidad submarina de la costa norte del Perú. Asimismo, se plantearon como objetivos específicos de diseño los siguientes: Seleccionar información visual de la biodiversidad submarina de la costa norte del Perú. Registrar el proceso de experimentación visual en cuanto a color, forma y textura del trabajo de investigación. De esa manera, se creará una colección de trajes de baño inspirada en las especies de la flora y fauna submarina localizadas en la costa norte peruana. / The porpouse of this investigation is to develop a female swimwear collection from the theoretical and visual analysis of the marine biodiversity of the north coast of Peru. In addition, to carry out the theoretical research the following specific objectives were raised: Explain the marine biodiversity of the north coast of Peru. Define the main concepts of marine biodiversity on the northcoast of Peru. Describe the situation of the marine biodiversity of the north coast of Peru. Likewise, the following specific deign objectives were proposed: Select visual information on the marine biodiversity of the nort coast of Peru. Record the process of visual experimentation in terms of color, shape and texture of the research work. In this way, a swimwear collection inspired by the species of the marine flora and fauna located on the Peruvian north coast will be created. / Trabajo de investigación

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