abstract: Anthropogenic land use has irrevocably transformed the natural systems on which humankind relies. Understanding where, why, and how social and economic processes drive globally-important land-use changes, from deforestation to urbanization, has advanced substantially. Illicit and clandestine activities--behavior that is intentionally secret because it breaks formal laws or violates informal norms--are poorly understood, however, despite the recognition of their significant role in land change. This dissertation fills this lacuna by studying illicit and clandestine activity and quantifying its influence on land-use patterns through examining informal urbanization in Mexico City and deforestation Central America. The first chapter introduces the topic, presenting a framework to examine illicit transactions in land systems. The second chapter uses data from interviews with actors involved with land development in Mexico City, demonstrating how economic and political payoffs explain the persistence of four types of informal urban expansion. The third chapter examines how electoral politics influence informal urban expansion and land titling in Mexico City using panel regression. Results show land title distribution increases just before elections, and more titles are extended to loyal voters of the dominant party in power. Urban expansion increases with electoral competition in local elections for borough chiefs and legislators. The fourth chapter tests and confirms the hypothesis that narcotrafficking has a causal effect on forest loss in Central America from 2001-2016 using two proxies of narcoactivity: drug seizures and events from media reports. The fifth chapter explores the spatial signature and pattern of informal urban development. It uses a typology of urban informality identified in chapter two to hypothesize and demonstrate distinct urban expansion patterns from satellite imagery. The sixth and final chapter summarizes the role of illicit and clandestine activity in shaping deforestation and urban expansion through illegal economies, electoral politics, and other informal transactions. Measures of illicit and clandestine activity should--and could--be incorporated into land change models to account for a wider range of relevant causes. This dissertation shines a new light on the previously hidden processes behind ever-easier to detect land-use patterns as earth observing satellites increase spatial and temporal resolution. / Dissertation/Thesis / Doctoral Dissertation Geography 2019

L’étude des articles sur la Colombie, publiés par El País, entre 1991 et 2002, constitue l’objet central de cette recherche. Une première partie, condense les relations presse et pouvoir et débouche sur une réflexion sur la presse et son histoire en Espagne, jusqu'à l’apparition du journal El País. Un parcours à travers l’histoire colombienne sert de cadre pour préciser l’espace où se déroulent les événements évoqués par le journal. La Colombie, ancienne colonie espagnole, fut d’abord connue en Espagne à travers les "Chroniqueurs des Indes", qui contribuèrent à la représentation négative de "l’Autre". Dans quelle mesure ces imaginaires persistent-ils dans El País? L’analyse quantitative et statistique de 1059 articles, signale dix catégories, dont trois se détachent : politique, conflit armé, et trafic de drogue.La deuxième partie comporte l´analyse qualitative des articles publiés entre 1996 et 2002, à partir des postulats de Teun Van Dijk. El País élabore comme "quatrième pouvoir", une image de la Colombie qui semblerait être déterminée par des préjugés et stéréotypes. / The research of the articles about Colombia published by El País from 1991 to 2002 is the main objective of this investigation. The first part summarizes the relationship between the press and power, while it reflects upon the press and its history in Spain until arriving the establishment of the newspaper El País. A journey through Colombian history serves as a framework to set the stage of the span of time investigated through the Madrid newspaper.Colombia, former Spanish colony, was known in Spain, firstly through the writings of the Cronista de Indias, which decided to present the Other. To what extent do these images persevere through El País? The quantitative and statistical analysis of 1,059 articles demonstrates 10 categories, three standing out: politics, armed conflict, and drug trafficking.The second part deals with the quantitative analysis of the published articles by the newspaper from 1996 and 2002 from the assertions of Teun Van Dijk. El País, from its structure, gives details as a “fourth power,” an image of Colombia that seems to be determined from prejudices and stereotypes.