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Coyoacán, Mexico

Aguirre Gomez R.,Institute Geografia
Investigaciones Geograficas | Year: 2014

This paper shows a hyperspectral optical analysis of Zumpango Lake, relict of one of the lakes that formerly filled the Basin of Mexico. The spectral signatures are dominated by the presence of phytoplankton and submerged vegetation. Integrated spectral curves have a good statistical correlation with chlorophyll a concentration values. It indicates that submerged vegetation water, mainly hyacinth (Eichhornia spp) and duckweed (Lemna sp), and phytoplankton are homogeneously distributed in the water body, which confers its characteristics of eutrophication.

By the mid nineteenth century, the telegraph became one of the technological networks with greater territorial penetration in European and United States economies. In a parallel fashion, and with the appropriate technical considerations, in this paper I examine one of such local networks from a geographical perspective: the Mexican telegraph network and its transition from a private, regional network to a public, country-wide one, during the crucial period from 1850 to 1910. The manner in which this technology was arranged further encouraged the centrality of Mexico City, the state modernization, and the surveillance and integration of the country's territory.

Oleschko K.,National Autonomous University of Mexico | Korvin G.,King Fahd University of Petroleum and Minerals | Flores L.,National Autonomous University of Mexico | Brambila F.,National Autonomous University of Mexico | And 5 more authors.
Geoderma | Year: 2010

We present a novel approach to multiscale fractal image analysis for monitoring the dynamics of the soil pore/solid network roughness due to moisture content changes. Roughness of the gray-level probability density function (PDF) of subsequent images of the drying soil was expressed in terms of its Hurst exponent (HPDF), which correlated significantly with the soil dielectric permittivity and gravimetric water content, as well as with micro-horizon depth and the temporal progress of drying. We documented an intermittent character of the water content dynamics, correlating with oscillations of the pore/solid interface roughness. Our technique of PDF roughness analysis of digital images, exemplified here for soil moisture monitoring, can be applied for monitoring the other complex systems, for instance plant growth in greenhouse. © 2009 Elsevier B.V.

In this article we analyzed the conflicts by the water in the state of Morelos, Mexico, between 2000 and 2010. The article has the intention to make a geographic characterization according to a systematization of national and local journalistic notes, referred to the conflicts by the water in Morelos. With the information of journalistic notes we generated a data base and we systematized the information, later we made an analysis of hierarchic conglomerates and space association to find geographic patterns of distribution of conflicts by the water.

Fuentes F.F.,Arturo Prat University | Bazile D.,CIRAD - Agricultural Research for Development | Bazile D.,Institute Geografia | Bhargava A.,University of Lucknow | Martinez E.A.,Catolica del Norte University
Journal of Agricultural Science | Year: 2012

Quinoa cultivation in Chile presents an ancient and active complex of geographic, climatic, social and cultural interactions that has determined its current biodiversity in the three main growing zones (north, central and south). Importantly, these interactions involve the participation of farmers, whose activities are at the base of seed exchange networks due to their knowledge and in situ conservation of genetic diversity. The present study reports how a better understanding of farmers' seed exchanges and local production practices could impact the genetic structure and diversity of quinoa at national scale in Chile. Using field interviews and characterization of 20 microsatellite genetic markers in a multi-origin set of 34 quinoa accessions representative of Chile and the South American region, the phenetic analysis of germplasm was consistent with the current classification of quinoa ecotypes present in Chile and Andean zone. This allowed the identification of five populations, which were represented by quinoa of Salares (northern Chile), Coastal/Lowlands (central and southern Chile), Highlands (Peru, Bolivia and Argentina) and Inter-Andean Valleys (Ecuador and Colombia). The highly informative quality of the markers used revealed a wide genetic diversity among main growing areas in Chile, which correlated well with natural geographical-edaphic-climatic and social-linguistic context to the expansion of quinoa biodiversity. Additionally, in addition to ancient seed exchanges, this process is still governed by the diverse agricultural practices of Andean farmers. Genetic erosion is considered an imminent risk due to small-scale farming, where the influence of increased migration of people to urban systems and export-driven changes to the agro-ecosystems may further reduce the diversity of quinoa plants in cultivation. © Cambridge University Press 2012.

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