Population, Land Use and Deforestation in the Pan Amazon Basin: a Comparison of Brazil, Bolivia, Colombia, Ecuador, Perú and Venezuela

This paper discusses the linkages between population change, land use, and deforestation in the Amazon regions of Brazil, Bolivia, Colombia, Ecuador, Perú, and Venezuela. We begin with a brief discussion of theories of population–environment linkages, and then focus on the case of deforestation in the PanAmazon. The core of the paper reviews available data on deforestation, population growth, migration and land use in order to see how well land cover change reflects demographic and agricultural change. The data indicate that population dynamics and net migration exhibit to deforestation in some states of the basin but not others. We then discuss other explanatory factors for deforestation, and find a close correspondence between land use and deforestation, which suggests that land use is loosely tied to demographic dynamics and mediates the influence of population on deforestation. We also consider national political economic contexts of Amazon change in the six countries, and find contrasting contexts, which also helps to explain the limited demographic-deforestation correspondence. The paper closes by noting general conclusions based on the data, topics in need of further research and recent policy proposals.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42720/1/10668_2003_Article_6977.pd

El hombre y los Andes. Tomo II

Este libro reúne las propuestas de destacados Investigadores de los Andes, quienes, como un homenaje académico en honor de Franklin Pease García Yrigoyen, fueron convocados a presentar trabajos originales en sus respectivos campos de investigación. Los estudios compilados abarcan nn amplio espectro temático une examina la historiografía, la literatura, las fuentes y la arqueologia andinas, asi como el Tahuantinsuyo, el virreinato, los inicios de la república y el siglo XX en la historia del Perú. La búsqueda de una identidad colectiva y la propuesta de un mundo mejor están presentes en luda la obra de Franklin Pease G.Y., uno de los más influyentes estudiosos de la tradición historiográfica peruana del siglo XX; similar espíritu es tabién el que anima a los colaboradores de este homenaje. El resultado obtenido es un panorama lozano y renovado de la investigación académica de la región que, al presentar imágenes y trayectorais mejo definidas, muestra que la historia es vida y que une armonioamente el quehacer cientifico con la experiencia cotidiana de los pueblos

Population genomics of post-glacial western Eurasia

Western Eurasia witnessed several large-scale human migrations during the Holocene1,2,3,4,5. Here, to investigate the cross-continental effects of these migrations, we shotgun-sequenced 317 genomes—mainly from the Mesolithic and Neolithic periods—from across northern and western Eurasia. These were imputed alongside published data to obtain diploid genotypes from more than 1,600 ancient humans. Our analyses revealed a ‘great divide’ genomic boundary extending from the Black Sea to the Baltic. Mesolithic hunter-gatherers were highly genetically differentiated east and west of this zone, and the effect of the neolithization was equally disparate. Large-scale ancestry shifts occurred in the west as farming was introduced, including near-total replacement of hunter-gatherers in many areas, whereas no substantial ancestry shifts happened east of the zone during the same period. Similarly, relatedness decreased in the west from the Neolithic transition onwards, whereas, east of the Urals, relatedness remained high until around 4,000 bp, consistent with the persistence of localized groups of hunter-gatherers. The boundary dissolved when Yamnaya-related ancestry spread across western Eurasia around 5,000 bp, resulting in a second major turnover that reached most parts of Europe within a 1,000-year span. The genetic origin and fate of the Yamnaya have remained elusive, but we show that hunter-gatherers from the Middle Don region contributed ancestry to them. Yamnaya groups later admixed with individuals associated with the Globular Amphora culture before expanding into Europe. Similar turnovers occurred in western Siberia, where we report new genomic data from a ‘Neolithic steppe’ cline spanning the Siberian forest steppe to Lake Baikal. These prehistoric migrations had profound and lasting effects on the genetic diversity of Eurasian populations.info:eu-repo/semantics/publishedVersio