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Through the understanding of cartography as an alternative representation tool, this paper researches the existing and usually invisible relationships between informal micro-activities and formal public spaces. For this purpose, Carapungo Entry Park located in the north of Quito (Ecuador), is taken as a case study, being a paradigmatic case of the complexity and multiplicity that constitutes informality in Latin American cities. After a first analysis based on the formal planning of this park, we will focus on dissident spatial practices carried out by inhabitants who occupy and appropriate a formal space. These situations of conflict originate spatial constructions based on spontaneity, fluidity, adaptability, movement, and temporality, which include local culture, economy, and social interaction. With the production of cartographies, the processes and activities generated by formal and informal vendors, passers-by, and public transport passengers, are made visible and analyzed. The expected results based on cartography as an alternative representation, are the presentation of relations of tensions, forces, conflicts, and negotiations that allow us to identify patterns, trends and behaviors that have no place in the supposed precision and rigor of the regulations in the formal planning of public space. [ABSTRACT FROM AUTHOR]

Lahars, here defined as debris flows of volcanic origin, are rapid mass movements that pose a serious threat to cities located in the vicinity of many volcanoes. Quito, capital city of Ecuador and placed at the foot of the Pichincha volcano complex, is exposed to serious inundation hazard as part of the city is built on numerous deposits of large lahars that have occurred in the last 10,000 years.The objective of this paper is to model the potential lahars of the Pichincha volcano to predict inundation areas within the city of Quito. For this purpose two models that apply different approaches were utilized and their results were compared.The programs used were LAHARZ, a semi-empirical model conceived by the United States Geological Survey (USGS), and FLO-2D, a hydraulic model distributed by FLO Software Inc. LAHARZ is designed as a rapid, objective and reproducible automated method for mapping areas of potential lahar inundation (Proc. First Int. Conf. on Debris Flow Hazards Mitigation, San Francisco, USA, ASCE, 1998, p. 176). FLO-2D is a two-dimensional flood routing model for simulating overland flow on complex surfaces such as floodplains, alluvial fans or urbanized areas (FLO-2D Users manual, version 99.2). Both models run within geographical information systems (GIS).Fieldwork was focused on collecting all available information involved in lahar modeling. A total of 49 channel cross-sections were measured along the two main streams and stratigraphic investigations were carried out on the fans to estimate the volume of previous events. A global positioning system was utilized to determine the coordinates of each cross-section. Further data collection concerned topography, rainfall characteristics and ashfall thicknesses. All fieldwork was carried out in cooperation with the Instituto Geofisico of the Escuela Politecnica Nacional.Modeling in a GIS environment greatly aided the exportation of results for the creation of thematic maps and facilitated model comparison. Evaluation of the models was performed by comparing simulation results against each other and against the geometry of existing lahar deposits. [Copyright &y& Elsevier]