Scielo RSS <![CDATA[Investigaciones geográficas]]> http://www.scielo.org.mx/rss.php?pid=0188-461120140003&lang=es vol. num. 85 lang. es <![CDATA[SciELO Logo]]> http://www.scielo.org.mx/img/en/fbpelogp.gif http://www.scielo.org.mx <![CDATA[<b>Editorial</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300001&lng=es&nrm=iso&tlng=es <![CDATA[<b>Evaluación de la exactitud posicional vertical de una nube de puntos topográficos lidar usando topografía convencional como referencia</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300002&lng=es&nrm=iso&tlng=es La exactitud vertical de datos lidar es normalmente establecida por proveedores comerciales en un EMC máximo de 0.150 m. Sin embargo, los resultados de evaluaciones de exactitud en las que se han utilizado datos de campo por lo menos tres veces más exactos que los datos lidar, sugieren que dicha exactitud se observa solo cuando la densidad de los datos lidar es mayor a un punto sobre el terreno por metro cuadrado. Desafortunadamente, el número de estos estudios es limitado y se requiere de la elaboración de otras evaluaciones que confirmen dicha hipótesis. En este estudio se evaluó la exactitud vertical de una nube de puntos topográficos lidar de una densidad de 1.02 puntos sobre el terreno por metro cuadrado, usando como referencia datos recolectados en campo mediante una estación total. Los resultados coinciden con aquéllos de estudios previos, por lo que se sugiere establecer la EPV de la nube de puntos topográficos lidar en 0.200 m para terreno mixto y de cambios constantes y en 0.150 m para terreno con cambios topográficos gentiles. Sin embargo, la EPV no refleja la magnitud del 95% de los errores bajo la presencia de errores sistemáticos, por lo cual es necesario incluir el percentil 95 de los errores en la documentación de datos lidar.<hr/>Lidar is an active remote sensing technology that reduces the cost and time required to collect topographic data. The vertical accuracy of lidar data is normally set by commercial data providers at a maximum root mean square error of 0.150 m. However, the results of accuracy assessments where field data at least three times more accurate than lidar data have been used suggest that that accuracy is only met when the density of the lidar data is higher than 1 ground points per square meter. Unfortunately, the number of these studies is limited and more accuracy assessments are needed in order to establish the vertical accuracy of lidar data. In this paper, the vertical accuracy of a topographic lidar cloud point with a density of 1.02 ground points per square meter is assessed for different types of terrain. Reference data was collected on the field using a total station with millimeter accuracy in order to meet the ASPRS requirements for the accuracy assessment of lidar data. The results suggest that the vertical accuracy of topographic lidar data exceeds the accuracy specifications of commercial data providers and, also, are consistent with previous studies where the vertical accuracy of lidar was assessed under similar conditions. Therefore, it is suggested to set the vertical positional accuracy (EPV, after its Spanish acronym) of the lidar point cloud in 0.200 m for mixed terrain with constant changes and in 0.150 m for areas with smooth topographic changes. However, under the presence of systematic errors, the EVP does not convey the magnitude of 95% of the vertical errors, as intended; therefore, it is recommended to include the 95th error percentile in the documentation of lidar data. <![CDATA[<b>Caracterización de las arenas y arcillas minerales de los depósitos de canal y planicie de inundación del río Portuguesa, Venezuela</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300003&lng=es&nrm=iso&tlng=es Este trabajo investiga la relación entre la mineralogía de sedimentos fluviales, su área fuente y el clima, en un tramo del río Portuguesa en los llanos centro-occidentales venezolanos. Para este estudio se recolectaron los sedimentos más antiguos depositados en la planicie aluvial y los más recientes depositados en el canal actual. Las arenas fueron separadas por tamizado en seco y las arcillas por Bouyoucos (1962); la mineralogía se determinó por Difracción de Rayos X. Los resultados indican que las arenas están compuestas principalmente por cuarzo, formando arenas maduras o cuarzo-arenitas. Su origen se relaciona con la desintegración físico-mecánica de las rocas del orógeno andino y la Cordillera del Interior, probablemente durante el Pleistoceno Tardío. Las arcillas están constituidas por cuarzo y caolinita, con cantidades menores de ilita, muscovita, clorita, vermiculita y montmorillonita. Se postula un origen detrítico para algunos de estos minerales ya que la caolinita, vermiculita y montmorillonita, también pueden ser neoformadas a partir de la alteración química experimentada por las micas y feldespatos durante el Pleistoceno Tardío-Holoceno. Se concluye que el origen y composición de los sedimentos de estos depósitos muestran estrecha relación con su área fuente y las condiciones climáticas que prevalecieron durante el Cuaternario Tardío.<hr/>Portuguesa river floodplain is one of the largest systems in the region of central western Venezuelan llanos. This sub-Orinoco River basin covers an area of 59 500 km² which means about 6.5% of the country. The basin includes two tectonic provinces, and the river and its tributaries flow through a geological mosaic composed of rocks different ages and mineralogical composition. The interest of this paper is to examine the mineralogical composition of sands and clays in the former and present sediments of the lower basin of the river and document the relationship between the mineralogy of river sediment source area and climate variations in this region during the Late Quaternary. Most of the tributaries of the Portuguese river transport sediments from the southern and southeastern ranges of the Andes and the Interior cordillera from the Caribbean range; other small rivers originate and transport sediments from the floodplain and from the oldest foothill terraces. The methodology consisted of collecting ancient sediments deposited in the floodplain and the current channel. For this study, 40 samples of sands associated with different pools of load current bed Portuguesa River and 23 samples of clay from the oldest sediments were collected; by core drilling on bar meanders and paleomeanders in the flood plain of the river. The sand fraction was separated by dry sieving and clays by the Bouyoucos (1962) method with some modifications. Mineralogical analyzes of both fractions was determined by X-ray diffraction for the case of sand the analysis was performed only on whole sample and clays were subjected to three treatments (total, ethylene glycol and heated sample at 550º) to detecting the presence of swelling clays. The results indicate that the sands are mainly composed of quartz, forming mature sand or quartz-arenites with lesser amounts of minerals such as chlorite, muscovite, calcite and albite, among others. Which identified peaks in the diffractograms quartz infer high crystallinity of quartz (3.3º) and a peak of lower intensity (4.2º). Meanwhile, in the clay fraction 13 crystalline mineral phases were determined mainly predominating well crystallized quartz (3.3º) and the well-crystallized kaolin (7.1º), illite (10 Aº) and muscovite (5.0 Aº). The origin of the sands is mainly related with the physical-mechanical disintegration of the rocks of the Venezuelan South Andean Cordillera orogen and the Caribbean range during arid climatic conditions that prevailed at the end of the Late Pleistocene and factors such as transport distance, residence time, pedogenesis, chemical weathering intensity and the source area. One detrital origin for quartz, illite and muscovite reported in the clay fraction, the origin of minerals kaolinite can be inherited from older or soil deposits associated with these fluvial sediments is postulated. However, as kaolinite and montmorillonite, vermiculite, neoformation may have originated from the chemical change experienced by the mica and feldspar, associated with wetter weather conditions, environment and intensely washed acidity conditions that characterize this tropical region. The influence of climate highlighted in the mineralogical evolution of sedimentary deposits reported in this study and suggests that the sediments were deposited from the Early to Late Holocene, under conditions similar to today's most humid tropical climate. It is concluded that the origin and composition of the sands and clays analyzed mainly show a close relationship with the source area of the sediments and factors such as the distance of sediment transport, the residence time in the channel and floodplain, the intensity of chemical weathering and climatic conditions that prevailed during the Late Pleistocene-Holocene. <![CDATA[<b>Geosites selection for touristic purpose at Ibitipoca/MG state park (PEI)</b>: <b>A proposal from numeric evaluation methodologies</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300004&lng=es&nrm=iso&tlng=es A criação de unidades de conservação permite, dentre outros, a valorização do patrimônio natural. Esse processo de valorização está associado à forma como a sociedade percebe o patrimônio, o que, consequentemente, vincula-se ao valor atribuído ao mesmo. O ato de atribuir valor a um patrimônio, seja natural ou cultural, surge, inicialmente, do entendimento da importância desse patrimônio. Esse entendimento, em específico nas unidades de conservação, depende de ações de educação e interpretação ambiental. Esse estudo tem por objetivo principal a seleção de geossítios para uso turístico no Parque Estadual do Ibitipoca, a partir de metodologias de avaliação numérica desses sítios geológicos. Essa seleção é relevante uma vez que direcionará, em estudos posteriores a serem realizados pelos presentes autores, as ações de valorização e divulgação do patrimônio geológico a serem implantadas no parque.<hr/>The creation of conservation units permits, among others, the valuing of the natural patrimony. This valuing process is associated to the way society perceives patrimony, which, consequently, is attached to the value attributed to it. The act of attributing value to a patrimony, be it natural or cultural, emerges, initially, from the understanding of the importance of such patrimony. This understanding, specifically in the conservation units, depends on environmental education and interpretation actions. Such study has as main objective the selection of geosites for touristic purpose at the Ibitipoca State Park, from the numeric evaluation methodology. That selection is relevant once it will direct, in post studies to be held by the current authors, the actions of valuing and publicizing of the geological patrimony to be implemented in the park. <![CDATA[<b>La revisión analítica del estado de arte en los servicios ecosistémicos y ambientales a nivel mundial y de México</b>: <b>un enfoque geográfico</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300005&lng=es&nrm=iso&tlng=es Within a strong international movement for conservation of natural resources, the term of Ecosystem Services (ES) which refers to all benefits that nature offers to society, was introduced at Rio Conference, 1992. After this, the first compensation scheme for ES, as one of the tools of the new environmental policy directed towards the principles of sustainable development, was proposed in Kyoto Protocol, 1997. Its objective is to prevent the reduction of natural resources' availability, and to improve human well-being by means of monetary compensation for conservation activities. Since then, the theme of ES found a global response, which was reflected in the implementation of payment programs and development of studies in many countries worldwide, where it's possible to note the different perspectives of analysis and aspects included, as well as methodology used. In this regard, this paper presents the state of art on ES and Environmental Services research (specific term adopted in public policy) in global and Mexican perspectives. It is based on the review of 1 781 scientific papers published in international peer-viewed journals between 1992 and 2012 (twenty years since Rio Conference). Furthermore, the work provides a sound geographical overview of the main ES topics studied and the relative contribution of papers per region, country and Mexican states. The presentation of results is helped by the construction of multi-scale maps and tables to show the evolution of studies in time and space, where a gradual continuous growth in numbers of publications with different focus and theories is detected, and use of distinct techniques from various disciplines, according to the specific objectives of each research. On the other hand, the social and economic standpoints dominate the global scene, with recent interest in integral analysis and ES compensation schemes. Geographically, ES research appears concentrated in North America, Europe, China and Australia, with social and economic focus of analysis predominat; followed by physical and interdisciplinary approaches. In the relation to the ecosystem function, the biodiversity studies prevail, followed by hydrological and carbon. Developing countries have published moderate or low amounts of papers, but are often the areas of interest for outside research. It is important to highlight that half of the papers are focused on one or more study cases, which allows for better understanding and analysis of local issues. Moreover, applied research combines experiments, sampling, surveys and interviews. It all contributes to providing better quality and more quantity of information for a successful study. In Mexico the situation is similar to the global trends, which is reflected in the growth trend of studies (since implementation of federal payment scheme in 2003) with social and physics focuses predominant and biodiversity and hydrological functions prevailing; and their very sharp heterogeneous territorial distribution and few publications about payment programs. Their spatial distribution appears less consistent with the totals than the distribution of article focus; the geographic allocation of ecosystem services seems more related to each area's history and issues. For example, hydrological services are most studied in states that have problems with water scarcity and distribution: Federal District, Mexico, Baja California and Querétaro. Biodiversity is more the object of study in regions with high levels of species richness or a history of conservation programs, as Chiapas, Michoacán and Veracruz. After this revision it is possible to mention the following challenges: the necessity of a mayor analysis of carbon capture function, development of the focus of economic and interdisciplinary researches, more homogeneous space studies, and in collaboration with institutions from other countries and internal. Also it is important to recognize other problems that limit study achievements, and consequently the general knowledge of the ES and ecosystem functions, for instance lack or misuse of information, scarcity of financial, technical or human resources, shortage of time, safe access to study case territories, as in Mexico, as in many others. We believe that the future of ES is in the endorsement of interdisciplinary publications, focused on analysis of socio-ecological system with a l ong-term vision.<hr/>El término de los servicios ecosistémicos (SE) se introdujo en la Declaración de Río en 1992, dentro de fuerte movimiento internacional por la gestión de los recursos naturales. En aquel entonces, el innovador principio se refirió a las funciones ambientales que mantienen a los sistemas de soporte vital. Para ilustrar esto, la polinización, la producción de oxígeno, la regulación de la temperatura, el almacenamiento, la filtración y la distribución del agua, entre otros, se enumeraron y se tomaron previamente por concedidos hasta que la acción humana los impugne. Los primeros esquemas de compensación por servicios ambientales se propusieron en 1997 como una de las herramientas de la nueva política ambiental dirigida hacia los principios del desarrollo sustentable. Desde entonces, el tema de los SE ha recibido notable respuesta a nivel mundial, que se refleja en la aplicación de programas de pago y en el desarrollo de los estudios en muchos países del mundo. Este trabajo en particular analiza el estado de arte de la investigación llevada a cabo hasta ahora en el tema de SE y servicios ambientales desde la perspectiva global y de México. Lo que se basa en la revisión de 1 781 artículos científicos publicados en revistas arbitradas de corte internacional entre 1992 y 2012. Además, ofrece un enfoque geográfico de análisis de los principales temas estudiados dentro de ES y de la emisión relativa de los artículos por región, país o estado. Los resultados son finalmente presentados y discutidos a la luz de las limitaciones encontradas y los retos a futuro. <![CDATA[<b>Análisis de la sequía y desertificación mediante índices de aridez y estimación de la brecha hídrica en Baja California Sur, noroeste de México</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300006&lng=es&nrm=iso&tlng=es En Baja California Sur (BCS) prevalecen climas muy secos-semicálidos y cálidos, asociados con la tendencia extremosa de las temperaturas diurnas y con la sequedad ambiental. En el estado, la temperatura máxima en verano sobrepasa los 40º C y la mínima oscila de 5 a 12º C, con mínima estatal de 2º C en invierno en la parte alta de la Sierra de La Laguna; solo en la región de Los Cabos se presenta un clima cálido subhúmedo. Debido a que la precipitación en el estado es escasa, oscilando de 310 mm en el sur del estado a 120 mm anuales en la porción norte, las predicciones y escenarios en condiciones de cambio climático apuntan hacia una acentuación de las sequías. Con los valores de temperatura y precipitación correspondientes a los diferentes escenarios de cambio climático para cuatro estaciones consideradas y mediante una modificación escalar del índice de De Martonne, se calcularon los indicadores IDHA índice de Disponibilidad Hidroambiental (IDHA) e índice de Sequía Hidroambiental (ISHA), para determinar su tendencia y la consecuente Brecha Hídrica Estandarizada (BHE), cuantificación innovadora del déficit hídrico, que se propone en este trabajo. El máximo valor de BHE (diez unidades), el cual indica prevalencia de sequía, se observa de febrero a junio en prácticamente todo el estado. Se concluye que el análisis de las tendencias de PP y t y su integración en indicadores biparamétricos constituyen una herramienta confiable para la construcción de escenarios y tendencias de cambio climático.<hr/>In Baja California Sur (BCS), Mexico, dry-semi warm and warm climates prevail associated to an extreme trend of diurnal temperatures and the environmental dryness. In this State, the maximum summer t exceeds 40º C and the minimum varies from 5 to 12º C, with a minimal for the State of 2º C in winter, at the top of the Sierra de La Laguna; only Los Cabos region has a warm humid climate. Because precipitation in the state is low, oscillating from 310 mm in the southern area of the state to 120 mm per year in the northern portion, predictions and scenarios under climate conditions point to an intensification of droughts. The aim of this work was to carry out a comparative analysis of trends of temperature, precipitation and hydro-environmental aridity among contrasting localities of BCS, by means of the application of Aridity Indexes and the determination of the Standardized Water Gap (BHE), through a numerical scale modification of the De Martonne Index. With the values of temperature and precipitation for the different climate change scenarios for four weather stations, the indicators Hydro Environmental Availability Index (IDHA) and Hydro Environmental Drought Index (ISHA) were calculated to determine their trend and the consequent BHE, an innovative quantification of water deficit, which is proposed in this paper. The maximum value of BHE (10 units), indicating prevalence of drought, is observed from February to June in almost the entire state. Results suggest that BHE tend to increase and intensify under climate change conditions, which is more evident from the South towards the North of the State. According to the trends of the indexes IDHA, ISHA and BHE, under six scenarios of climatic change for four regions of BCS, BHE can be estimated with a major significance for the region Gustavo Díaz Ordaz-Vizcaíno, Mulegé County, in the North of the State, where may reach a value BHEmax = 10 and BHEmin = 7.23, values which suggest extreme dryness, corresponding to the maximum values among localities. We conclude that the analysis of trends in PP and t and their integration into bi-parametric indicators are a reliable tool for the construction of scenarios and climate change trends. <![CDATA[<b>Caracterización de la Pequeña Edad de Hielo en el México central a través de fuentes documentales</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300007&lng=es&nrm=iso&tlng=es La Pequeña Edad de Hielo (PEH) es el periodo corto y frío que, de acuerdo con aportes de las últimas décadas, se manifestó en temporalidad e intensidad de manera distinta a lo largo y ancho del planeta. A través de fuentes documentales se busca brindar una aproximación de la forma en que se manifestó la PEH en el México central entre principios del siglo XVII y mediados del XIX, en particular de lo acontecido durante los denominados mínimos Maunder y Dalton. En el ámbito hispanoamericano, los registros de las ceremonias de rogativa, albergados en los archivos civil y eclesiástico de las ciudades que fueron sedes obispales, son la fuente documental más precisa. Los ceremoniales de rogativa dedicados a diversas advocaciones o sus reliquias comenzaban a ganar prestigio en España y ser registrados periódicamente, gracias a cuerpos administrativos más regulados en ayuntamientos y catedrales, hacia la época en que ocurrieron las primeras exploraciones trasatlánticas. Estas manifestaciones públicas de la iglesia católica tenían la finalidad de pedir por buenos temporales (para evitar extremos en precipitación o temperatura), contra las epidemias y por el bienestar de autoridades civiles o eclesiásticas.<hr/>Comparing instrumental climatic sources with proxy data, in order to review existing climatic models and to acknowledge climatic variability in time and space, is widely recognized nowadays. In Mexico the study of past climate along the last 500 hundred years, has mostly been conducted through the analysis of instrumental sources. Studies that have 1877 as time limit, when the first continuous records started to be taken in Mexico City. For the study of climate along the last centuries, documentary sources have proved their accuracy, if compared to physical and biological data, usually modified by human activity. Tree ring information is among biological sources also useful for recent centuries, but in Mexico it is still necessary to have a better regional coverage. The Little Ice Age (LIA) was defined back in the 1930s through information gathered in North America and Western Europe, but much is still unknown about the climatic behavior of lower latitudes in the Northern Hemisphere and the Southern one during LIA. The reconstruction of past climates, through documentary sources started under scientific principles, only until the mid 20th century and it was a task conducted mostly by British and French authors. Emmanuel Le Roy Ladurie, recognized French historian, was the first to reveal to the world in the early 1960s, the documentary source that has resulted more precise for climatic reconstruction within the Hispanic cultural realm: the record of the rogation ceremonies. But it was not until the 1990s, when Spanish researchers like Mariano Barriendos, Javier Martín-Vide or Fernando S. Rodrigo, published and disseminated outside Spain, the climatic data obtained at City Councils and Cathedrals throughout the Iberian peninsula. In Mexico this kind of work started to be achieved by 2001. Rogation ceremonies are a reliable source of ancient climatic variability, because of its public and institutional origin, and their homogeneous information and precise dating. Central Mexico is where most of this sort of research has been conducted in Latin America. The information obtained comes from the City council's and Cathedral archives of the following cities: Mexico City, Puebla, Morelia and Guadalajara (also from Durango in Northwestern Mexico trying to acknowledge climatic patterns in a larger area). With the information obtained, the characteristics and intensity of the Maunder and Dalton minimums in solar spots, coldest spells of LIA, have been acknowledge for Central Mexico. According to Lonnie Thompson and colleagues after their research at the Quelccaya glacier, they were able to define a humid LIA (ca. 1500-1720) and a dry LIA (ca. 1720-1880) for Western South America: the climatic data obtained through the consulting of Rogation ceremonies records recognizes the same pattern for Central Mexico. The minimum Maunder (M.m.) has been proposed to occur worldwide between 1645 and 1715, the data obtained at Mexican City councils and Cathedrals suggest a later beginning (ca. 1660-1680) and hazardous years between 1680 and 1720. The late minimum is more humid than the Dalton minimum (D.m.) in Central Mexico. During M.m., 18 years show excess rainfall, while only 8 years were recorded under such circumstances between 1730 and 1830. Droughts are also less frequent during M.m. and they were usually ended by intense rainfall seasons. The D.m. is usually considered warmer than the M.m. around the planet, however in Central Mexico, the first one is much colder, since nearly 50% of all the frosting sever enough to be registered by City or Cathedral councils took place between 1780 and 1820. Rogation ceremony records have also shown regional differences within Central Mexico, during the D.m. the Western part of this area shows a more humid pattern during its first stage, but after 1800, the Eastern part shows more rainfall than the Western one. Furthermore, rogation ceremony records, because of their precise dating, can show us if rainy seasons were late, if falls and winters were very dry and can even prove the intensity and duration of canículas (mid rain season dry periods common in Mexico, Central America and the Caribbean), warm and dry spells that can compromise summer time food production, specially maize harvesting. <![CDATA[<b>Adaptación a la variabilidad climática entre los caficultores de las cuencas de los ríos Porce y Chinchiná, Colombia</b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300008&lng=es&nrm=iso&tlng=es Este artículo pretende dar cuenta de las prácticas usadas por algunos caficultores de dos cuencas andinas colombianas para enfrentar la variabilidad climática. La información fue recogida a través de entrevistas, observaciones en las fincas y talleres. Los resultados indican que el manejo de la sombra en los cafetales, la renovación con variedades resistentes a la roya, la asociación de cultivos, las coberturas vegetales, la siembra escalonada y la reforestación son estrategias utilizadas para minimizar los efectos de la variabilidad climática. Sin embargo, en una de las cuencas estas estrategias son más frecuentes que en la otra, donde la producción ha cambiado hacia un sistema más tecnificado. Los caficultores utilizan además otras alternativas como el agroturismo, la integración de la mano de obra familiar, la asociatividad comunitaria y gremial, el jornaleo y estrategias de comercialización como los mercados justos y las certificaciones que ayudan a mejorar los precios de venta para resistir los momentos de crisis.<hr/>This article seeks to explain the practices used by small farmers to cope with climate variability and extreme weather events in the basins of the Chinchiná and Porce rivers located on the central Andes in Colombia. The information wasglacie collected through interviews, observations on farms and workshops with farmers. Additionally historical averages on temperature, precipitation and sunshine were compared with those values recorded in 2010 during the transition between El Niño an La Niña events. During the first quarter of 2010 the average temperature in Chinchiná increased by 1.4 Cº and the solar brightness by 14%, while the precipitation experienced a 46% reduction. In contrast, during the second half of the year there was a decrease of 0.8 Cº in temperature, a 31% reduction in solar brightness and an increase in precipitation of 62%. The coffee production in the years 2011 and 2012 was the lowest in the country in the last 35 years despite the cultivated area increased. These changes affected the coffee plantations and substantially decreased grain coffe production. Coffee production in the years 2011 and 2012 was the lowest in the country in the last 35 years despite the cultivated area increase. These fall in coffee production was also a result of the renewal with rust resistant varieties, which at that time had not yet begun to produce. Most of the farmers have 5 hectares or less and are union members in the National Federation of Coffee Growers of Colombia (FNCC), which provides multiple services to them including an extension service with spread of the findings of field investigations carried out by the National Coffee Research Center (CENICAFE). These study results indicates some strategies used by peasants to minimize the effects of climate variability: the shade management in coffee plantations, especially with banana (Musa sp.) and guamo (Inga sp); their renewal with the rust resistant variety named Castillo; the association of crops, particularly coffee, maize and bean; the use of mulches, organic fertilizers and mycorrhizae; a proper fertilization; the cultivation of two-axis coffee plants; the staggered planting of coffee in different plots and the reforestation of hillsides and births water, especially with (Guadua angustifolia), are strategies used to minimize the effects of climate variability. However these strategies are more frequent in Porce than in Chinchiná where sun coffee plantations and intensive agriculture are predominants. The article indicates that adaptation to climate variability is not achieved only by technological measures if do not decrease the sources of vulnerability of the rural population. The farmers are more exposed to the effects of weather because of their poverty, as a result of building on steep slopes, by cause of the volatility in the international price of coffee, by virtue of the exchange rate, due to the lack of a culture of crop insurance and for the lack of generational renewal in agriculture. Additionally peasants in Chinchiná faced threats of earthquakes, eruption of Nevado del Ruiz volcano, susceptibility of volcanic soils to mass removals and glacier melting, an increasingly process accelerated by climate change. This paper also highlights the social, economic and political adaptation strategies to climate variability. We found that the resilience of rural households increases when resorting to agrotourism, integration of family labor, associations, political mobilization for claiming benefits, casual wage labor on other farms, integration to fair markets coffee and coffee certifications that increase the price of This work also highlights the social, economic and political adaptation strategies to climate variability. We found that the resilience of rural households increases when resorting to the agrotourism, integration of family labor, the union associations, political mobilization for claiming benefits, the casual wage labor on other farms, the integration to fair markets of coffee and coffee certifications that increase the price of grain of coffee grain. Not all spontaneous adaptation measures are positive, it is necessary to evaluate the experience of many coffee farms of medium length that were converted to livestock, rural tourism and citrus growing. Since climate change and climate variability has increased the frequency and intensity of extreme weather events, this work also helps to identify vulnerabilities and adaptation of rural populations to climate change and extreme events. <![CDATA[<b>Los transportes y la logística en las cadenas globales de producción del sector de la moda rápida</b>: <b>el caso de la empresa española <i>Inditex</i></b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300009&lng=es&nrm=iso&tlng=es The concept of the global production network expressively covers the spatial interrelationships characteristic of the economy due to the existence of worldwide flows of information, raw materials, components, and finished products. Recent geographical analyses of global production networks in different economic sectors demonstrate that little attention has been paid to the logistical and transport systems through which networks are fully integrated. Nevertheless efficient logistics and transport services are essential to an understanding of their organisational and geographical structure. The supply chains of big fashion retailers provide a good example because the choice of global or local supply depends on whether suppliers rely on efficient transport and logistics systems that let them compensate for higher relative costs compared with developing countries -in the case of local supply- or the costs deriving from their greater distance to the market -in the case of global supply. In addition the challenges presented by the functional and geographical integration of fashion production networks can only be overcome if global retailers manage their logistics efficiently and leverage the differentiated advantages of the modes of transport in relation to time. This paper on Inditex, a Spanish leading group in the fashion sector, analyses how transport and logistics fit into the production network and provide the firm with one of its most notable competitive advantages. We first discuss the dilemmas that fashion retailers face when organising the supply chain and the contribution of logistics and transport to its functional and geographical integration. We then open the study of Inditex by describing the network of shops and manufacturing, presenting the principles of the logistical model, and providing details of the procedures applied for the functional and geographical integration of the chain of production of Zara, the best known of the company's 11 brands. The analysis, based on recent and previously unpublished data on the brand's logistics hub in Zaragoza (northeast Spain), sheds light on the modus operandi of the group and confirms the crucial importance of logistics in all facets of the production model. First, efficient logistics and sufficiently fast transport, allow the company to enjoy short lead times and be present in economically and geographically very disparate markets. Second, the productive structure, combining nearby and distant manufacturing, and both dispersion and concentration spatially and in production, also relies on the effectiveness of the logistical model. On the one hand, better internal and external communication and greater productivity compensate for the company's higher costs of manufacturing in nearby areas. On the other, the vigour of the four clusters of suppliers in Asia (China, Pakistan, Bangladesh, and India) rests on the availability of efficient logistics and transport services, including air transport, which ameliorate the costs of their distance to the company's distribution centres in Spain and other markets. Finally, we offer details of how the Inditex group completely centralises the distribution of its products to shops. The data for the Zara logistics hub in Zaragoza (North East of Spain) illustrate the value given to time in the company's activities and how this consideration influences the organisation of the flows in and out of the hub. Air transport is used to send garments to distant markets and also for the reception of high-fashion-content garments from the Asian clusters and for their quick delivery to various markets despite the distance. The results provide evidence for considering logistics and transport as key facilitators for the Inditex expansion, but we understand that the effects described in the paper can extend to the fast fashion sector as a whole in that the geographical configuration of global networks increasingly depends on the organisational and logistical strategies that the firms adopt in order to meet the needs of time-sensitive customers. At the conclusion we remind that a heavy dependence on energy and the likelihood of fuel price increases threaten the future viability of a logistic model based on the present unrealistic cheapness of fast transport. As establishing the scope and reach of these aspects would require complementary analysis, we finish the paper whith tuh hope of having stimulate interest for a better understanding of the logistical and transport systems within the global production networks in a possible new economic and environmental context.<hr/>El análisis geográfico de las cadenas globales de producción en diferentes sectores económicos ha prestado poca atención a los sistemas logísticos y de transporte que permiten la integración espacial completa de dichas cadenas. Este artículo sobre Inditex, empresa líder en el sector de la moda rápida, sale al paso de dicha carencia, analizando cómo el encaje del transporte y la logística en sus redes de producción otorgan a dicha compañía una de sus principales ventajas competitivas. El texto describe la red de tiendas y fábricas, presenta los principios del modelo logístico y ofrece algunos detalles sobre los procedimientos aplicados para lograr la integración geográfica y funcional de la cadena de producción de Zara, la más conocida de las once marcas de la compañía. Entre otros aspectos, se resalta el creciente uso del transporte aéreo en las cadenas de suministro de productos con alto contenido en moda fabricados en países distantes, así como en la distribución de prendas a los mercados más alejados. También queda patente la importancia de la variable tiempo en la configuración geográfica de las redes globales de este sector rápida. Por ello el artículo concluye señalando la necesidad de prestar una mayor atención a las estrategias organizativas y logísticas que adoptan las empresas para mantener y aumentar su competitividad global en este ámbito. <![CDATA[<b><i>Território na Geografia de Milton Santos</i></b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300010&lng=es&nrm=iso&tlng=es The concept of the global production network expressively covers the spatial interrelationships characteristic of the economy due to the existence of worldwide flows of information, raw materials, components, and finished products. Recent geographical analyses of global production networks in different economic sectors demonstrate that little attention has been paid to the logistical and transport systems through which networks are fully integrated. Nevertheless efficient logistics and transport services are essential to an understanding of their organisational and geographical structure. The supply chains of big fashion retailers provide a good example because the choice of global or local supply depends on whether suppliers rely on efficient transport and logistics systems that let them compensate for higher relative costs compared with developing countries -in the case of local supply- or the costs deriving from their greater distance to the market -in the case of global supply. In addition the challenges presented by the functional and geographical integration of fashion production networks can only be overcome if global retailers manage their logistics efficiently and leverage the differentiated advantages of the modes of transport in relation to time. This paper on Inditex, a Spanish leading group in the fashion sector, analyses how transport and logistics fit into the production network and provide the firm with one of its most notable competitive advantages. We first discuss the dilemmas that fashion retailers face when organising the supply chain and the contribution of logistics and transport to its functional and geographical integration. We then open the study of Inditex by describing the network of shops and manufacturing, presenting the principles of the logistical model, and providing details of the procedures applied for the functional and geographical integration of the chain of production of Zara, the best known of the company's 11 brands. The analysis, based on recent and previously unpublished data on the brand's logistics hub in Zaragoza (northeast Spain), sheds light on the modus operandi of the group and confirms the crucial importance of logistics in all facets of the production model. First, efficient logistics and sufficiently fast transport, allow the company to enjoy short lead times and be present in economically and geographically very disparate markets. Second, the productive structure, combining nearby and distant manufacturing, and both dispersion and concentration spatially and in production, also relies on the effectiveness of the logistical model. On the one hand, better internal and external communication and greater productivity compensate for the company's higher costs of manufacturing in nearby areas. On the other, the vigour of the four clusters of suppliers in Asia (China, Pakistan, Bangladesh, and India) rests on the availability of efficient logistics and transport services, including air transport, which ameliorate the costs of their distance to the company's distribution centres in Spain and other markets. Finally, we offer details of how the Inditex group completely centralises the distribution of its products to shops. The data for the Zara logistics hub in Zaragoza (North East of Spain) illustrate the value given to time in the company's activities and how this consideration influences the organisation of the flows in and out of the hub. Air transport is used to send garments to distant markets and also for the reception of high-fashion-content garments from the Asian clusters and for their quick delivery to various markets despite the distance. The results provide evidence for considering logistics and transport as key facilitators for the Inditex expansion, but we understand that the effects described in the paper can extend to the fast fashion sector as a whole in that the geographical configuration of global networks increasingly depends on the organisational and logistical strategies that the firms adopt in order to meet the needs of time-sensitive customers. At the conclusion we remind that a heavy dependence on energy and the likelihood of fuel price increases threaten the future viability of a logistic model based on the present unrealistic cheapness of fast transport. As establishing the scope and reach of these aspects would require complementary analysis, we finish the paper whith tuh hope of having stimulate interest for a better understanding of the logistical and transport systems within the global production networks in a possible new economic and environmental context.<hr/>El análisis geográfico de las cadenas globales de producción en diferentes sectores económicos ha prestado poca atención a los sistemas logísticos y de transporte que permiten la integración espacial completa de dichas cadenas. Este artículo sobre Inditex, empresa líder en el sector de la moda rápida, sale al paso de dicha carencia, analizando cómo el encaje del transporte y la logística en sus redes de producción otorgan a dicha compañía una de sus principales ventajas competitivas. El texto describe la red de tiendas y fábricas, presenta los principios del modelo logístico y ofrece algunos detalles sobre los procedimientos aplicados para lograr la integración geográfica y funcional de la cadena de producción de Zara, la más conocida de las once marcas de la compañía. Entre otros aspectos, se resalta el creciente uso del transporte aéreo en las cadenas de suministro de productos con alto contenido en moda fabricados en países distantes, así como en la distribución de prendas a los mercados más alejados. También queda patente la importancia de la variable tiempo en la configuración geográfica de las redes globales de este sector rápida. Por ello el artículo concluye señalando la necesidad de prestar una mayor atención a las estrategias organizativas y logísticas que adoptan las empresas para mantener y aumentar su competitividad global en este ámbito. <![CDATA[<b><i>La política de ordenamiento territorial en México</i></b>: <b><i>de la teoría a la práctica</i></b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300011&lng=es&nrm=iso&tlng=es The concept of the global production network expressively covers the spatial interrelationships characteristic of the economy due to the existence of worldwide flows of information, raw materials, components, and finished products. Recent geographical analyses of global production networks in different economic sectors demonstrate that little attention has been paid to the logistical and transport systems through which networks are fully integrated. Nevertheless efficient logistics and transport services are essential to an understanding of their organisational and geographical structure. The supply chains of big fashion retailers provide a good example because the choice of global or local supply depends on whether suppliers rely on efficient transport and logistics systems that let them compensate for higher relative costs compared with developing countries -in the case of local supply- or the costs deriving from their greater distance to the market -in the case of global supply. In addition the challenges presented by the functional and geographical integration of fashion production networks can only be overcome if global retailers manage their logistics efficiently and leverage the differentiated advantages of the modes of transport in relation to time. This paper on Inditex, a Spanish leading group in the fashion sector, analyses how transport and logistics fit into the production network and provide the firm with one of its most notable competitive advantages. We first discuss the dilemmas that fashion retailers face when organising the supply chain and the contribution of logistics and transport to its functional and geographical integration. We then open the study of Inditex by describing the network of shops and manufacturing, presenting the principles of the logistical model, and providing details of the procedures applied for the functional and geographical integration of the chain of production of Zara, the best known of the company's 11 brands. The analysis, based on recent and previously unpublished data on the brand's logistics hub in Zaragoza (northeast Spain), sheds light on the modus operandi of the group and confirms the crucial importance of logistics in all facets of the production model. First, efficient logistics and sufficiently fast transport, allow the company to enjoy short lead times and be present in economically and geographically very disparate markets. Second, the productive structure, combining nearby and distant manufacturing, and both dispersion and concentration spatially and in production, also relies on the effectiveness of the logistical model. On the one hand, better internal and external communication and greater productivity compensate for the company's higher costs of manufacturing in nearby areas. On the other, the vigour of the four clusters of suppliers in Asia (China, Pakistan, Bangladesh, and India) rests on the availability of efficient logistics and transport services, including air transport, which ameliorate the costs of their distance to the company's distribution centres in Spain and other markets. Finally, we offer details of how the Inditex group completely centralises the distribution of its products to shops. The data for the Zara logistics hub in Zaragoza (North East of Spain) illustrate the value given to time in the company's activities and how this consideration influences the organisation of the flows in and out of the hub. Air transport is used to send garments to distant markets and also for the reception of high-fashion-content garments from the Asian clusters and for their quick delivery to various markets despite the distance. The results provide evidence for considering logistics and transport as key facilitators for the Inditex expansion, but we understand that the effects described in the paper can extend to the fast fashion sector as a whole in that the geographical configuration of global networks increasingly depends on the organisational and logistical strategies that the firms adopt in order to meet the needs of time-sensitive customers. At the conclusion we remind that a heavy dependence on energy and the likelihood of fuel price increases threaten the future viability of a logistic model based on the present unrealistic cheapness of fast transport. As establishing the scope and reach of these aspects would require complementary analysis, we finish the paper whith tuh hope of having stimulate interest for a better understanding of the logistical and transport systems within the global production networks in a possible new economic and environmental context.<hr/>El análisis geográfico de las cadenas globales de producción en diferentes sectores económicos ha prestado poca atención a los sistemas logísticos y de transporte que permiten la integración espacial completa de dichas cadenas. Este artículo sobre Inditex, empresa líder en el sector de la moda rápida, sale al paso de dicha carencia, analizando cómo el encaje del transporte y la logística en sus redes de producción otorgan a dicha compañía una de sus principales ventajas competitivas. El texto describe la red de tiendas y fábricas, presenta los principios del modelo logístico y ofrece algunos detalles sobre los procedimientos aplicados para lograr la integración geográfica y funcional de la cadena de producción de Zara, la más conocida de las once marcas de la compañía. Entre otros aspectos, se resalta el creciente uso del transporte aéreo en las cadenas de suministro de productos con alto contenido en moda fabricados en países distantes, así como en la distribución de prendas a los mercados más alejados. También queda patente la importancia de la variable tiempo en la configuración geográfica de las redes globales de este sector rápida. Por ello el artículo concluye señalando la necesidad de prestar una mayor atención a las estrategias organizativas y logísticas que adoptan las empresas para mantener y aumentar su competitividad global en este ámbito. <![CDATA[<b><i>Estudios de geografía humana de México</i></b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300012&lng=es&nrm=iso&tlng=es The concept of the global production network expressively covers the spatial interrelationships characteristic of the economy due to the existence of worldwide flows of information, raw materials, components, and finished products. Recent geographical analyses of global production networks in different economic sectors demonstrate that little attention has been paid to the logistical and transport systems through which networks are fully integrated. Nevertheless efficient logistics and transport services are essential to an understanding of their organisational and geographical structure. The supply chains of big fashion retailers provide a good example because the choice of global or local supply depends on whether suppliers rely on efficient transport and logistics systems that let them compensate for higher relative costs compared with developing countries -in the case of local supply- or the costs deriving from their greater distance to the market -in the case of global supply. In addition the challenges presented by the functional and geographical integration of fashion production networks can only be overcome if global retailers manage their logistics efficiently and leverage the differentiated advantages of the modes of transport in relation to time. This paper on Inditex, a Spanish leading group in the fashion sector, analyses how transport and logistics fit into the production network and provide the firm with one of its most notable competitive advantages. We first discuss the dilemmas that fashion retailers face when organising the supply chain and the contribution of logistics and transport to its functional and geographical integration. We then open the study of Inditex by describing the network of shops and manufacturing, presenting the principles of the logistical model, and providing details of the procedures applied for the functional and geographical integration of the chain of production of Zara, the best known of the company's 11 brands. The analysis, based on recent and previously unpublished data on the brand's logistics hub in Zaragoza (northeast Spain), sheds light on the modus operandi of the group and confirms the crucial importance of logistics in all facets of the production model. First, efficient logistics and sufficiently fast transport, allow the company to enjoy short lead times and be present in economically and geographically very disparate markets. Second, the productive structure, combining nearby and distant manufacturing, and both dispersion and concentration spatially and in production, also relies on the effectiveness of the logistical model. On the one hand, better internal and external communication and greater productivity compensate for the company's higher costs of manufacturing in nearby areas. On the other, the vigour of the four clusters of suppliers in Asia (China, Pakistan, Bangladesh, and India) rests on the availability of efficient logistics and transport services, including air transport, which ameliorate the costs of their distance to the company's distribution centres in Spain and other markets. Finally, we offer details of how the Inditex group completely centralises the distribution of its products to shops. The data for the Zara logistics hub in Zaragoza (North East of Spain) illustrate the value given to time in the company's activities and how this consideration influences the organisation of the flows in and out of the hub. Air transport is used to send garments to distant markets and also for the reception of high-fashion-content garments from the Asian clusters and for their quick delivery to various markets despite the distance. The results provide evidence for considering logistics and transport as key facilitators for the Inditex expansion, but we understand that the effects described in the paper can extend to the fast fashion sector as a whole in that the geographical configuration of global networks increasingly depends on the organisational and logistical strategies that the firms adopt in order to meet the needs of time-sensitive customers. At the conclusion we remind that a heavy dependence on energy and the likelihood of fuel price increases threaten the future viability of a logistic model based on the present unrealistic cheapness of fast transport. As establishing the scope and reach of these aspects would require complementary analysis, we finish the paper whith tuh hope of having stimulate interest for a better understanding of the logistical and transport systems within the global production networks in a possible new economic and environmental context.<hr/>El análisis geográfico de las cadenas globales de producción en diferentes sectores económicos ha prestado poca atención a los sistemas logísticos y de transporte que permiten la integración espacial completa de dichas cadenas. Este artículo sobre Inditex, empresa líder en el sector de la moda rápida, sale al paso de dicha carencia, analizando cómo el encaje del transporte y la logística en sus redes de producción otorgan a dicha compañía una de sus principales ventajas competitivas. El texto describe la red de tiendas y fábricas, presenta los principios del modelo logístico y ofrece algunos detalles sobre los procedimientos aplicados para lograr la integración geográfica y funcional de la cadena de producción de Zara, la más conocida de las once marcas de la compañía. Entre otros aspectos, se resalta el creciente uso del transporte aéreo en las cadenas de suministro de productos con alto contenido en moda fabricados en países distantes, así como en la distribución de prendas a los mercados más alejados. También queda patente la importancia de la variable tiempo en la configuración geográfica de las redes globales de este sector rápida. Por ello el artículo concluye señalando la necesidad de prestar una mayor atención a las estrategias organizativas y logísticas que adoptan las empresas para mantener y aumentar su competitividad global en este ámbito. <![CDATA[<b><i>Urbanización, Sociedad y Ambiente</i></b>: <b><i>experiencias en ciudades medias</i></b>]]> http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S0188-46112014000300013&lng=es&nrm=iso&tlng=es The concept of the global production network expressively covers the spatial interrelationships characteristic of the economy due to the existence of worldwide flows of information, raw materials, components, and finished products. Recent geographical analyses of global production networks in different economic sectors demonstrate that little attention has been paid to the logistical and transport systems through which networks are fully integrated. Nevertheless efficient logistics and transport services are essential to an understanding of their organisational and geographical structure. The supply chains of big fashion retailers provide a good example because the choice of global or local supply depends on whether suppliers rely on efficient transport and logistics systems that let them compensate for higher relative costs compared with developing countries -in the case of local supply- or the costs deriving from their greater distance to the market -in the case of global supply. In addition the challenges presented by the functional and geographical integration of fashion production networks can only be overcome if global retailers manage their logistics efficiently and leverage the differentiated advantages of the modes of transport in relation to time. This paper on Inditex, a Spanish leading group in the fashion sector, analyses how transport and logistics fit into the production network and provide the firm with one of its most notable competitive advantages. We first discuss the dilemmas that fashion retailers face when organising the supply chain and the contribution of logistics and transport to its functional and geographical integration. We then open the study of Inditex by describing the network of shops and manufacturing, presenting the principles of the logistical model, and providing details of the procedures applied for the functional and geographical integration of the chain of production of Zara, the best known of the company's 11 brands. The analysis, based on recent and previously unpublished data on the brand's logistics hub in Zaragoza (northeast Spain), sheds light on the modus operandi of the group and confirms the crucial importance of logistics in all facets of the production model. First, efficient logistics and sufficiently fast transport, allow the company to enjoy short lead times and be present in economically and geographically very disparate markets. Second, the productive structure, combining nearby and distant manufacturing, and both dispersion and concentration spatially and in production, also relies on the effectiveness of the logistical model. On the one hand, better internal and external communication and greater productivity compensate for the company's higher costs of manufacturing in nearby areas. On the other, the vigour of the four clusters of suppliers in Asia (China, Pakistan, Bangladesh, and India) rests on the availability of efficient logistics and transport services, including air transport, which ameliorate the costs of their distance to the company's distribution centres in Spain and other markets. Finally, we offer details of how the Inditex group completely centralises the distribution of its products to shops. The data for the Zara logistics hub in Zaragoza (North East of Spain) illustrate the value given to time in the company's activities and how this consideration influences the organisation of the flows in and out of the hub. Air transport is used to send garments to distant markets and also for the reception of high-fashion-content garments from the Asian clusters and for their quick delivery to various markets despite the distance. The results provide evidence for considering logistics and transport as key facilitators for the Inditex expansion, but we understand that the effects described in the paper can extend to the fast fashion sector as a whole in that the geographical configuration of global networks increasingly depends on the organisational and logistical strategies that the firms adopt in order to meet the needs of time-sensitive customers. At the conclusion we remind that a heavy dependence on energy and the likelihood of fuel price increases threaten the future viability of a logistic model based on the present unrealistic cheapness of fast transport. As establishing the scope and reach of these aspects would require complementary analysis, we finish the paper whith tuh hope of having stimulate interest for a better understanding of the logistical and transport systems within the global production networks in a possible new economic and environmental context.<hr/>El análisis geográfico de las cadenas globales de producción en diferentes sectores económicos ha prestado poca atención a los sistemas logísticos y de transporte que permiten la integración espacial completa de dichas cadenas. Este artículo sobre Inditex, empresa líder en el sector de la moda rápida, sale al paso de dicha carencia, analizando cómo el encaje del transporte y la logística en sus redes de producción otorgan a dicha compañía una de sus principales ventajas competitivas. El texto describe la red de tiendas y fábricas, presenta los principios del modelo logístico y ofrece algunos detalles sobre los procedimientos aplicados para lograr la integración geográfica y funcional de la cadena de producción de Zara, la más conocida de las once marcas de la compañía. Entre otros aspectos, se resalta el creciente uso del transporte aéreo en las cadenas de suministro de productos con alto contenido en moda fabricados en países distantes, así como en la distribución de prendas a los mercados más alejados. También queda patente la importancia de la variable tiempo en la configuración geográfica de las redes globales de este sector rápida. Por ello el artículo concluye señalando la necesidad de prestar una mayor atención a las estrategias organizativas y logísticas que adoptan las empresas para mantener y aumentar su competitividad global en este ámbito.