Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

In this work, a procedure to generate synthetic accelerograms using wavelets is presented. General criteria and its applicability are presented, as well as conclusions of practical use to generate synthetic accelerograms for use in geotechnical or structural analysis and soil-structure interaction. Synthetic accelerograms are generated for different types of soils (rigid soils and soft soils of Mexico City and Caleta de Campos, Michoacán) and for several objective spectra as they are: normative design spectra, uniform hazard spectra and spectra derived of envelopes of seismic records. The stability of the method to generate synthetic accelerograms associated to any objective spectrum is shown, in addition to demonstrating that the modifications suffered by the Fourier spectra as well as the Arias intensities when this method is used to adjust real signals are minimal. With the examples shown in this work, it is concluded that the generation of the accelerograms employing wavelets is very stable and starting from the same seismic records it can generate synthetic accelerograms for different objective spectra.

During recent earthquakes in Mexico, it has been observed that despite a proper behavior of the structure, there are failures and damage among non-structural elements. This paper presents analytical time-history analysis and results of the seismic behavior of “floor to floor” precast concrete facades. This analysis includes the evaluation of accelerations and displacements at the supports of the panels in a 15-story building. For the structural design, the 2004 Mexico City code has been used. An incremental dynamic analysis was carried out using the record of the 1985 earthquake at the site SCT. It has been observed that after reducing the seismic design forces by ductility and over strength, it may be possible to ignore that the actual forces are larger than the design forces, which may cause damage to the precast concrete facades.

En México, los estudios criosféricos, mayormente dentro del ámbito glaciológico de sus altas montañas, dieron inicio en la segunda mitad de los años 50 con los trabajos de Sidney E. White (1956) y José L. Lorenzo (1964), este último en preparación para el Año Geofísico Internacional 1957/1958. A partir de entonces se llevó a cabo una amplia serie de investigaciones en la alta montaña mexicana.

Muestra Pageant of the Pacific. Mapas de Miguel Covarrubias. Biblioteca Justino Fernández, Instituto de Investigaciones Estéticas, Universidad Nacional Autónoma de México. Ciudad Universitaria, Cd. Mx., del 5 de junio al 15 de octubre 2018

This paper discusses the results obtained from the inventory of ethnographic and biological heritage associated with the Huichol Route by the Sacred Sites to Huiricuta, Mexico (Tatehuari  Huajuyé), which served as reference to document and support its inclusion in the World Heritage List of the Convention Concerning the Protection of the World Cultural and Natural Heritage of the Organization of the United Nations Educational, Scientific and Cultural Organization (UNESCO, for its acronym in English). This framework was considered to contextualize its intrinsic attributes of universal value and the environmental degradation challenges it currently faces, so as to ensure its reversion and effective protection. The itinerary consists of a number of intertwined paths traveled by Huichol pilgrims, or wixaritari, from their respective community and family temples (located in the Sierra Madre Occidental, at the confluence of the States of Jalisco, Nayarit, Durango and Zacatecas), to the vicinity of Sierra de Catorce, in the semi-arid region of the potosino highlands. It runs through a heterogeneous relief with alternating mountain ranges, valleys, ravines and plateaus that alternate from the Pacific Ocean coast to the highlands. From an anthropological perspective, this route is the most important and representative remnant of the broad network of exchange routes that connected and enriched culturally the ancient peoples of America during thousands of years; in addition, it stands out for its high hierarchy in the huichol ritual cycle, its frequency of use, and its educational and socio-cultural role. In the ecological context, the environment along the Route includes a sequence of vegetation types and habitats of special relevance due to their contribution to biodiversity, which are home to extremely valuable flora and fauna, as rated in technical and legal protection documents, both national and international.            Field information was obtained through more than 20 ad-hoc expeditions and field trips organized over the past two decades with the permission, support and participation of the Huichol traditional authorities of Santa Catarina Cuexcomatitlan (Tuapurie) community , among others. This information was classified according to subject (anthropological, cultural, geographical, biological and legal), and was tailored to produce original documentary and multidisciplinary support entered into a geographical information system. The analysis of this information leads to the proposed nomination in the category of Associative Cultural Landscape, which highlights the exceptional dynamism of the relationships between culture and nature. The selection and delimitation of its integrative units considered, on the one hand, cultural attributes, based primarily on the anthropological significance of the landscapes, the location of the sacred sites and their hierarchy within the ritual cycle; and, on the other, the biological features in terms of the presence, distribution and the degree of preservation of habitats and species of interest for conservation. This was supplemented with information related to uses of the territory, threats, ethnobotanical uses, imagery, etc. The consideration of part or all of the attributes included enabled to justify each of the criteria of exceptional universal value selected, to support the proposal in accordance with the Operational Guidelines for the implementation of the World Heritage Convention, namely: Criterion (iii): Bear a unique or at least exceptional testimony to a cultural tradution or to a civilization which is living or which has disappeared; Criterion (v): be an outstanding example of a traditional human settlement, land use or sea use which is representative of a culture or human interaction with the environment; Criterion (vi): be directly or tangibly associated with events or living traditions, with ideas, or with beliefs, with artistic and literary works of outstanding universal significance. Criterion (x): contain the most important and significant natural habitats for in-situ conservation  of biological diversity, including threatened species.            At the cartographic level, the proposal covers a selection of 19 polygons representing a surface area of 135360 ha and a buffer zone of 512473 ha, spread along the route between the States of Nayarit and San Luis Potosí. These polygons concentrate the greatest density of sacred sites, habitats and species of interest. Although the proposal is the first nomination to the World Heritage List of an Associative Cultural Landscape linked to an live indigenous tradition in Latin America, the pressures from various government and business sectors linked to the exploitation of natural resources jeopardize its inscription and, hence, the preservation of the universal heritage associated with it.

The key objectives of this work are to analyze the socio-economic implications arising from the growth of tourism in the coast of Bacalar lagoon (Quintana Roo, Mexico), particularly those related to land tenure; and to analyze the local tourist discourse produced by the public policy of the Pueblos Mágicos (Magic Towns) Program. We conducted an extensive search of literature and documents, supplemented by field work including semi-structured interviews applied to members of the business, public, and farming sectors, as well as to organizations of the civil society. Maps were constructed based on a participatory cartography that involved land owners, and through the visual interpretation of high-resolution Google Earth (2012) satellite images, which made possible to understand and reconstruct the recent occupation process of the Bacalar Lagoon littoral.The socio-economic intensification process related to tourism and its effect on the change of land use were studied in four localities of the Bacalar municipality situated on the coast of the lagoon or very close to it: Bacalar, Aaron Merino Fernández, Buenavista and Pedro Antonio Santos. In recent years, the economy of these localities (in both the agriculture and the business sectors) and the different levels of government have been incorporated to the tourist market in two specific ways. On the one hand, the marketing of farming land located near the lagoon began in Bacalar from the decade of 1960 and resumed and intensified in the past two decades; on the other, the Magical Towns Program is an ongoing initiative that started in in 2006, promoted by the Secretariat of Tourism of the Mexican government. Tourist occupation of the coast has been materialized by the construction of temporary-residence houses both along the lagoon littoral and in the localities as such. This residential growth has undergone several stages whose social, economic and environmental processes are detailed in the body of this work. These include the strong pressures by economic agents (real estate, entrepreneurs, and government officials with political power, among others) to achieve the marketing of agricultural land. The Magical Towns Program that lies within the larger context above has focused primarily on the town of Bacalar (municipal seat), associated with changes in infrastructure and urban image of downtown Bacalar carried out by the local government, based on the adoption of architectural elements resembling those in other towns of Mexico, which has produced a diffuse staging and cultural identity for both visitors and local residents. These modifications aim to favor mainly local entrepreneurs in the accommodation sector. In parallel with this process, real estate speculation has gained momentum as the value of farming land increased, more so when Bacalar became an independent municipality in 2011. The overall findings of this study highlight that Bacalar lagoon has been a key driver in the reconfiguration of landscape and the local dynamics of tourism, related to the real estate development of temporary residences and the emergence of a spatial imaginarium marketed as a tourist attraction linked with the forced creation of a “Magic Town”. Although the two processes occurred in different times, these were linked, on the one hand, by the conditions of land value and, on the other hand, by the production of the imaginarium from the aesthetic value of the lagoon; the spatial outcome has been a tourist residential area along the littoral of the lagoon, resulting from the constant speculation developed over recent decades.  Of this speculative process, 45% of land use along the lagoon coast corresponds to temporary residence households with negative impacts derived from the lack of urban planning, in evident opposition to the economic benefits generated by the sale of farming land. In general, the implementation of the Magic Towns Program has produced economic benefits for the locality, but under strong socioeconomic inequalities in the outskirts.

During the past three government terms, the mining industry has recorded an exceptional growth in Mexico. The increase in the global demand for minerals and the consequent rise in the international prices of most of them led our country to rapidly become one of the five main global mining investment targets, particularly as regards mineral exploration. In this way, the renewed interest in Mexican mining was associated with increased foreign investment through the arrival of foreign companies, mostly from Canada, as well as an increased and higher share of domestic private investment.This mining boom was marked, at the same time, by an unprecedented territorial expansion of mining. In little less than three decades, the surface area granted to mining activities grew not only in those states that have historically stood out as mineral extraction centers, but also in states where this activity was either previously non-existent or conducted at a very small scale.Within this context, this article analyzes the behavior of the territorial expansion of mining over the past seventeen years in the State of Morelos. For the assessment of this perspective of the mining activity, the work includes four sections. The first summarizes recent research in geography focused on the territorial expansion of mining as an accumulation-by-disposession process. The second describes the methodology used for collecting and analyzing two indicators that support the results: number of titles and surface area granted. Thirdly, the assumptions and aspects of the increase in mining surface at a national scale are reviewed . It is discussed that mining expansion constitutes a capital-accumulation approach based on the dispossession of extensive areas of the subsoil, the evolution of which was driven directly by the amendments led by the federal government to the legal framework related to the ownership and exploitation of mineral resources, as well as the growing presence of junior Canadian mining companies. Finally, the article analyzes the behavior and effects of the mining concessions granted over the past seventeen years in the State of Morelos, showing that the concessions to extract metallic minerals grew substantially during the boom that took place between years 2004 and 2013, under a mechanism in which mining companies and private entities were free to decide where, when, and how to explore and exploit minerals, as well as to whom to sell their concession titles. All this took place regardless of the local needs, and even at the expense of these needs; the current and foreseeable land use was not considered either, and the communities affected were not previously consulted. This indicates that the territorial expansion of mining in Morelos has operated through the dispossession of the last remaining collective richness that had not been exploited: rivers, aquifers, hills, springs, Natural Protected Areas, and archaeological sites. As part of this territorial expansion, also addressed are the events that occurred as a result of the attempt to develop an open-pit mine called "Cerro Jumil" in the vicinity of the Xochicalco Archaeological Zone (selected as a World Heritage site in 1999). This mining project undertaken by the company Esperanza Resources, a subsidiary of the Canadian mining company Alamos Gold, triggered the Morelos Movement Against Mining Concessions of Precious Metals (MMCMMP), whose social resistance actions managed to frustrate the implementation of the project, and thereby changed the course of the potential effects that the mining company sought to minimize, even when these were evident given its proximity not only to the archaeological site, but also to the city of Cuernavaca, the political capital of the state of Morelos. It is concluded, therefore, that social repudiation is the only barrier that has managed to restrain the expansion of mining activities in this State, which evidences the need to modify the mechanisms regulating the issuance of mining concession titles in Mexico by the government.

Landslides are geomorphological processes that occur continuously in the Earth's relief and are caused by natural and anthropic factors. Such phenomena have set off a series of major economic and social disasters. To mitigate these hazards, it is necessary to determine the causes, spatial patterns, and factors that produce this gravitational phenomenon.In Mexico, a large number of landslides have occurred in recent years, many of them in the Trans-Mexican Volcanic Belt. These gravitational phenomena have been addressed by gathering historical or multitemporal inventories and using various heuristic, statistical, and deterministic methods to produce landslide susceptibility maps. However, there are few geomorphological studies that relate the area and frequency of these processes with the susceptibility of landforms.This research is based on studies of the stream system of La Cienega river watershed on the estern flank of Nevado de Toluca volcano, Mexico. The climatic, topographic, and geological conditions make the study area prone to episodic landslides and debris flows that pose a threat for people living along the stream system.  For example, in 1940 rainfalls triggered landslides on the upper portions of La Cienega watershed. Landslide sediments increased the destructive power of a debris flow that caused loss of life and property at the town of Santa Cruz in the municipality of Tenango del Valle, State of Mexico.  As a result of this event, the local inhabitants rebuilt the village, named Santa Cruz Pueblo Nuevo thereafter; however, the village was relocated with no proper planning in the lower part of the watershed on an alluvial fan, which is prone to further landslides and debris flows. Despite of their importance, there is a lack of landslide inventories to support the assessment of landslide susceptibility in the watershed.  Our work focuses on two secondary streams located in the southern portion of La Ciénega watershed. These secondary streams are referred as La Cieneguilla 1 (ASC1) and La Cieneguilla 2 (ASC2). In both tributaries, a detailed landslide inventory and a geomorphological map were carried out to determine the landslide susceptibility of the various landforms.The analytical methodology encompasses four main stages to assess landslide susceptibility. During the first stage, background information was gathered to provide an overall characterization of landslide processes across the watershed. Background information includes geology, land use, climate and hydrology, landslide maps and reports currently available, etc. In the second stage, a single historic landslide inventory map was elaborated using sets of satellite images from different times, supplemented with fieldwork. One hundred seventy-nine landslides were mapped and documented in the GIS. During the third stage, a geomorphological map was built from interpretation of aerial photographs, a digital elevation model (MDE), geology, and morphometric maps. The geomorphological map allowed to highlight the major landforms in the watershed. The fourth stage stablished landslide susceptibility by landform using landslide frequency and area. This method follows and adapts the Landslide Hazard Protocol of the Washington State Department of Natural Resources.    The results show that debris slides are the most frequent processes along the two secondary streams, with the potential to affect the village of Santa Cruz Pueblo Nuevo and other rural areas. Three of the fourteen major landforms located along the two secondary rivers show the highest landslide susceptibility. In these landforms, factors such as steep slopes, geological faults, and slope morphology influence the abundance and distribution of landslides.

Population aging is the most important demographic phenomenon in Mexico in the twenty-first century (Ham, 2003; Ordorica, 2012); it will be predominantly urban, and its socio-spatial dimension is just starting to be investigated in detail (Garrocho and Campos, 2005, 2016; Negrete, 2003; Zamorano et al., 2012). This article aims to set the methodological bases to analyze this demographic phenomenon, using several indices such as segregation, marginalization and the multifunctionality evidenced spatially, in order to estimate the spatial of elderly people in the Mexico City Metropolitan Area (MCMA).In this sense, the main objectives of the proposal are to: 1) estimate the multifunctionality of the segregation areas of highly-marginalized elderly people in the MCMA; 2) identify critical areas due to low multifunctionality; and, 3) outline socio-spatial policy measures aimed at improving the multifunctionality conditions and welfare of the elderly population living in these critical areas.To carry out this research, the work is divided into four sections. The first addresses the theoretical approach, showing three perspectives to explain the issue of spatial segregation and marginalization through three basic approaches: (i) New Urbanism; (ii) Compact and Smart City; and (iii) Assets , vulnerability and opportunity structure (AVEO).The second section proposes a methodology to explain how diversity and density of access to goods and services is expressed spatially through the concept of multifunctionality, understood as the diversity of opportunities in the everyday space to access and use ordinary goods and services (Batty et al., 2004), available for a specific group in the population (elderly people), assuming there is more than one activity or role in a given area and at the same time (coincidence in time and space: Batty et al., 2004). In this regard, we built a profile for elderly people according to their daily needs of access to goods and services.The most important idea underlying this methodological proposal is the transportation cost to be borne by elderly people to access and use key goods and services. This cost is not only economic, but also includes other dimensions such as commuting time, effort, or risk, which can be more important than economic costs in the scale of everyday space, particularly for the population of elderly persons (Cascetta et al., 2014; Garrocho y Campos, 2016).The cost of the above implications was explored through the concept of threshold distance, which considers the distances that elderly people can cover comfortably by walking. This threshold models the functional organization of the everyday space, and shows, through an analysis of  displacement networks, the feasibility to reach goods and services.The third section discusses the main results, analyzing the effects of multifunctionality as a spatial capital factor based on the information on segregation indices for elderly people presented by Garrocho y Campos (2006), as well as the marginality index (Conapo, 2017) in the MCMA. This analysis helped to know the degrees of both indices and the delimitation of areas of priority attention.From this, the results are identified and correlated at a human scale, micropolitana (neighborhood) scale, in order to explain the results at a delegation and/or municipality level to subsequently identify neighborhoods, revealing their spatial structure in relation to the analysis of the indices (segregation and marginalization) and their multifunctionality.Finally, section four deals with the findings and contributions from this work, highlighting the importance of establishing urban public policies specific to elderly persons.This work localized areas with various degrees of segregation, exclusion and multifunctionality, which reveal diferences in spatial patterns between the periphery and the center of the MCMA. This first diagnosis identifies priority areas for the implementation of public policies for elderly persons, and also gives an overview of the diversity and density expressed in multifunctionality, which is reflected in the different levels of spatial capital for this population sector.This research seeks to show the usefulness of methods involving a spatio-temporal approach over traditional (non-spatial) approaches for the study of aging at the urban scale.

The development strategies that have been adopted in Latin America and the Caribbean have led to serious damage for heritage and life. Therefore, we analyze the major risks and the preservation potential of UNESCO World Heritage sites, to propose new approaches for preserving the heritage in Latin America. Methodologically, the research involves two analytical stages: i) definition of the issues with risk potential in the region (approaches and connections); ii) risk (R) identification and heritage preservation potential (PP) in Latin America (summary table for sites in Peru, Mexico, Cuba, Panama and Brazil). The empirical analysis (seven sites in five countries) produces variables that may promote the development of risk management policies for sites and life, as well as reinforce the territorial heritage and territory of exception concepts in alternative preservation practices in Latin America and the Caribbean. When considering the major risks, unavoidable losses, and the existence of potential preservation sites in the continent identified from the cases investigated, it is obvious that risk management policies on patrimonial praxis have the capability to develop a less instrumental and functional rationale, becoming more human. Tourism (from theoretical and practical perspectives) can be perceived as an alternative for social development and not only as a threat. The empirical evidence across the continent reveals variations in the tourism status of each site, correlated with the contents of the uses of the territory: formal households vs slums, local trade or tourism, spatial policy of collective ownership vs private property. The generalization of abstract criticism of tourism is irrelevant, leads to the loss of local potential, hinders the importance of popular power in territorial-heritage issues; powerful criticism is derived from specific analyzes. Supporting tourist practices that involve popular stakeholders — that are connected materially and emotionally with the territory — will lead to the minimization of damages related to the uses of heritage and the spatial stigma.