Revista Geográfica de Chile Terra Australis <p><strong><span style="vertical-align: inherit;"><span style="vertical-align: inherit;">ISSN 0378-8482 versión impresa</span></span></strong></p> <p><strong><span style="vertical-align: inherit;"><span style="vertical-align: inherit;">ISSN 0719-9562 versión en línea</span></span></strong></p> <table width="100%" cellspacing="4" cellpadding="4" border="0"> <tbody> <tr> <td width="26%"> <p><img src="/public/site/images/admin/cover-terra-australis-small.JPG"></p> </td> <td width="74%"> <p><em><span style="vertical-align: inherit;"><span style="vertical-align: inherit;">Revista Geográfica de Chile Terra Australis</span></span></em><span style="vertical-align: inherit;"> <span style="vertical-align: inherit;">is a peer-reviewed, open access, electronic journal published jointly by the Instituto Geográfico Militar and the Disaster Risk Management Observatory of the Universidad Bernardo O'Higgins. The journal publishes high quality hypothesis-selected and purely descriptive studies that improve our understanding of Earth Sciences at all kinds of spatial scales (local, regional or global).</span></span></p> </td> </tr> </tbody> </table> en-US <p>The articles in Revista Geográfica de Chile Terra Australis are published under&nbsp;<a href="" target="_blank" rel="noopener">Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0)</a>.</p> <p><a href=""><img src="/public/site/images/admin/Screenshot_2021-03-24_Creative_Commons_—_Attribution-NonCommercial_4_0_International_—_CC_BY-NC_4_0.png" width="201" height="60"></a></p> (Fabiola Barrenechea Riveros) (Denisse Candia Cruz) Thu, 31 Dec 2020 00:00:00 -0300 OJS 60 Effects of Climate Change on the glaciers of the Nevados de Chillán Volcanic Complex <p class="western" style="margin-bottom: 0.28cm; line-height: 100%;" align="justify"><span style="font-family: Arial, serif;"><span style="font-size: small;"><span lang="en">Global scale climate change is affecting different ecosystems, including glaciers, main freshwater reserve on the planet. The main objective of this work was to determine the surface changes in the glacial coverings of the Nevados de Chillán-Volcanic Complex and relate them to meteorological variations to understand the effects of climate change on this type of ecosystem. Through a multitemporal analysis of Landsat TM and OLI images from 3 different periods (1999, 2009 and 2019), a spectral analysis was performed based on two indexes: 1) Normalized Difference Vegetation Index (NDVI) and 2) Normalized Difference Snow Index (NDSI). As for the two meteorological variables analyzed, precipitation and ambient temperature, the monthly averages were considered during the same dates from which the satellite images were obtained. The results obtained in this investigation indicate a superficial decrease in the temporal evolution of glaciers when analyzing the spectral indexes. In the two meteorological variables analyzed, variations were observed that support the hypothesis of how climate change is contributing to the melting of glaciers with the increase in environmental temperatures and the decrease in rainfall in the area of study. The work carried out highlights the notable decrease in glacial surfaces and how climate change could be directly related to this process.</span></span></span></p> <p class="western" style="margin-bottom: 0.28cm; line-height: 100%;" align="justify">&nbsp;</p> Carlo Cristian Lara Peña, Muller De Moraes ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Short Life Climate Pollutants (ccvc). A vehicle for improving air quality and mitigating Climate Change <p>This report attempts to constitute a solution to the so-called climate change through other alternatives. The proposal by the author, although not the only one, is to reduce short-lived climate pollutants (SLCPs), essentially linked to the increasing use of different activities. This expression emphasizes the short time of life that some pollutants usually remain in the atmosphere, <em>contrary sensu</em> of others that remain centuries to disappear. This is the purpose of this report. At the same time, some mitigation measures are proposed for these short-lived pollutants that could of course be expanded and perfected by those who have the decision-making power in these matters. The document concludes with suggestions on the next steps that could be taken in this matter whose concern is of all humanity. The document is part of a larger report prepared by the author.</p> Daniel Oscar Lipp ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Validation of digital elevation models in the Central Andes of Chile <p>This study validated the vertical exactitude and accuracy of seven digital elevation models DEM (SRTM X-SAR, SRTMv3 void voided 1 arcsec, SRTMv3 void filled 3 arcsec, SRTM GL1 Ellip, Aster GlobalDEM v3 2019/08. Alos World 3D 30m v21 2018/04,TamDEMx), considering both regional and local scale in middle/ higher mountain areas of the central Andes of Chile. Exactitude and Accuracy were determined using metrics and/or statistical tests reviewed by the National Institute of Standardization (INN), tests that considered the elevation data of 149 ground control acquired trough several GNSS surveys, and 1825 gcp provided by IceSat-2 mission records. At the regional scale, the results of the error estimation between the observed and the predicted value indicate that the DEM SRTM X-SAR is the most precise and vertically accurate set (21,3 m of exactness equivalent to 85% of exactitude; RMSEz = 21,7 m of precision equivalent to 86.8% of accurate). However, the band layout does not allow calculations that ensure the completeness of an area greater than 2500 sqkm. Then, the next option is the DEM Alos World 3D 30m v21 2018/04 (22,5 m of exactness representing 90% of exactitude; RMSEz = 23 m equivalent to 92% of accurate). Locally, and first considering the entire area and all IceSat-2 data, and then only those measurements in stable zones, in both cases the Alos World 3d is the most exactly and vertically accurately DEM, followed by the DEM AsterGDEMv3 19/08. The poorest indicators belong to the DEM TamDEMx</p> Diego Alfonso Soza ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Impact analysis of 2014 fire in the Vergel, Valparaíso Region <p>In Valparaíso, during the month of April 2014, a forest fire spread through seven hills of the commune of the same name, affecting more than 1,000 hectares and 2,900 homes, and is known as "The Great Fire of Valparaíso" because of the impact it had on the population and the environment.</p> <p>The purpose of this study is to analyze the impact of the fire in a sector of the population of El Vergel on the hill of La Cruz, which is an area close to the initial focus of the fire, which presents favorable geomorphological characteristics for the propagation of the flames, product of the abrupt slopes, zones of urban-rural interface and an urbanistic disorder that has been increasing, leaving more exposed the buildings of the sector.</p> <p>To carry out the research, the method of multi-temporal study was used from images captured at different times by an airborne photogrammetric sensor, from which different products were generated as georeferenced mosaics and planimetry of the area, from which an analysis was made with geospatial information system programs, managing to quantify and assess the damage caused by the disaster, as well as the reconstruction of buildings, to finally determine the high-risk areas and mitigation measures implemented after the event.</p> <p>This research methodology is available to different public or private organizations to be replicated not only for forest fires, but for any type of disaster.</p> Fernando González Aliste, Yonathan Quintana Jara ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Alexander Von Humboldt's Cosmos in the Dialectic of Enlightenment <p>In the process of conformation of modern sciences, Geography passed through an epistemological construction process, founded on the Kantian difference between “the celestial order above me” and “the moral order inside me”. Circumstance that implied the recognition of a strict control over time and space, consolidated as of the domination of the representations field, whose main spatial expression is the Cosmos by Alexander Von Humboldt. Part of the modern state consolidation, and constitutive element of the Enlightenment’s mythical ideals, colonial domination and abstract language construction that allows to homogenize reality. Here we explore the particularities of the process, as of the importance of Cosmos.</p> Gabriel Petatán ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Multi-temporal analysis of soil changes for the Thomas Van Der Hammen Forest Reserve - Bogotá <p>In this article, the purpose is to monitor the Thomas van der Hammen forest reserve, the largest urban forest reserve in Colombia between 1977 and 2017. The analysis focuses on the change that occurs in land cover for the northern zone of the city of Bogotá, especially to observe and identify the causes and the specific areas from which the urban expansion of the towns to the north of the city and two of its neighboring municipalities (Chía and Cota) begins to be generated. This study frames a special relevance due to the context of change of government in Bogotá focused on a change in the land use plan and the possible urbanization of said reserve. To carry out this multitemporal analysis, various satellite images (Spot, RapidEye and Landsat) were classified in established periods of time and thus compare the information over time and quantify both the land cover and the area of ​​change per period and accumulated. The study shows as the most impressive result the accelerated increase in construction land, which went from 500 hectares in 1977 to more than 5,100 hectares in 2017, which allows concluding the existence of a critical change that entails a direct impact on the structure. ecological reserve and where concepts such as the sustainable development of the Colombian capital are tested.</p> José Leonardo Hurtado, Diego Mauricio Pulido, Iván Alberto Lizarazo ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Digital Soil Mapping: An option for Chile <p>The current soil mapping produced by CIREN, covers a part of the current needs of the country related to soils of agricultural and forestry aptitude; at detail scales, however, there is a lack of soil studies and associated mapping related to such particular ecosystems as highland soils, wetland water soils, high mountain soils, soils of remote regions and island territories, both in detail and in thematic recognition and mapping. It is understood that this involves a high cost for field activities, however, digital soil mapping is able to cover a series of aspects related to the extension and spatial distribution of soils as predictive models for the growing demand in ecological and environmental aspects. Through the SCORPAN model, it is possible to generate a cartography that represents soil classes and thematic properties. Pedotransfer functions allow to estimate unknown variables through known soil properties, fitting to regression models. The capture of terrain morphological records together with soil samples that analyze physical, chemical and biological properties allow the use of these records as training data to validate the transfer functions.</p> <p>This trial seeks to reflect the importance of applying digital soil mapping models in Chile for better resource management.</p> Mauricio Calderón ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Effects of the transformation of the north-south axis to Autopista Central in Santiago de Chile <p>Autopista Central is a route that has undergone a metamorphosis throughout the last half of the twentieth century, since its genesis as a street with two lanes in the fifties to be a "free flow"&nbsp; concessionary highway, available only for those who can afford it. This modality responds to the principles of the neoliberal economic model implanted in the country, in the seventies.</p> <p>&nbsp;</p> <p>The present study focuses on inquiring into the territorial conflicts that have brought the transformation of the road from public to private use in an area of influence of five hundred meters, looking at it from a local scale above of a regional one. A point of view that is contrary to what the state looks at it, because the implementation of large-scale infrastructure in the middle of the capital city, positions itself as a banner of economic growth, however, the project does not consider the protection of the surrounding community social welfare, which is affected by spatial biases, as well as health and safety problems.</p> Renata Paz Porcell Lizama ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Determination of Altitude Correction Factors for Digital Elevation Models <p>Using Digital Elevation Models (DEMs) imparts a necessity for checking its accuracy and precision, due to their variety of applications, whether in private or public projects. For this purpose, understanding the contribution of geodesy as a basic science, oriented towards the results earth measurements and calculations, is revealed. Therefore, vertical accuracy this study aims determinate from assignment and altimetric comparison between 4 geometric levelling considering 3 open source DEMs: SRTM, ASTER GDEM and PALSAR. Also, worlds standard geopotential models (EGM-96 and EGM-2008) were analyzed to verify specific vertical reference system adjustment for each model. Then, the objective proposed in the present work describes a methodology for determination of local altitudinal correction factors, conditioned by the use of an observation equation, which allows determining more probable values, based on the principle of Least Squares, this means, the equation was implemented, and factors were obtained to correct the vertical altimeter accuracy.</p> <p>Regarding the analysis, this was carried out based on a set of 132 samples, which are located close to a 116 km linear trajectory</p> Rodrigo Esteban González ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 Assessment of vegetation aptitude to accomodate organic beekeeping <p>The aptitude offered by land vegetation to accommodate organic beekeeping was assessed in the Santuario Apícola Paz de Aculeo, located in the Metropolitan Region of Chile. A multicriteria analysis methodology combining geomatics and remote sensing was designed. For this purpose, critical vegetation variables for forage selection by the bee populations were valued on the main vegetation units cadastrated for the study area. Thereafter, they were subject to a lineal combination that hypothesized several weighting scenarios. The afore-mentioned enabled to classify the units according to their aptitude to accommodate the beekeeping, which were further characterized according to their vegetation vigor throughout the phenological cycle; derived from NDVI (normalized difference vegetation index) composites, as well as to their topographic variability; derived from a DEM (digital elevation model). The results show that no matter the scenario supposed, the vegetation units of the study area can be divided into five aptitude classes, with those embracing the highest aptitude (1 and 2) as the most prevailing; being distributed at variable altitudes of generally southwest aspect. Although the NVDI composites yielded differences between classes, those were small and non-significant, as a variance analysis pointed out. This study seeks to approximate the management and planning of the beekeeping productive system of local scale to the geotechnologies usage. Further efforts could apply a similar methodology on more complex and heterogeneous vegetation areas with the aim of proving its versatility.</p> Marco Antonio Peña, Diego Arce Zegers ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300 EDITORIAL <div class="page" data-page-number="1" data-loaded="true"> <div class="textLayer"> <div>&nbsp;</div> <div>&nbsp;</div> <div>En el mundo globalizado en el que vivimos, cada vez toma mayor relevancia el manejo oportuno y eficiente de los datos disponibles en los diferentes medios y plataformas que la tecnología&nbsp;nos ofrece,&nbsp;así, el adecuado análisis y uso de ellos permitirá generar la información necesaria para adoptar las mejores decisiones dentro de un escenario de incertidumbre determinado.</div> <div>En este contexto, es posible comprender la existencia de una gran variedad de datos alojados en esta inmensa red de fuentes interconectadas y el potencial que conlleva lograr relacionarlos&nbsp;y transformarlos&nbsp;en</div> <div>información útil,&nbsp;asimismo, también es posible dimensionar la ventaja que nos entrega uno de los&nbsp; componentes que&nbsp;intrínsecamente poseen dichos datos y que bien utilizados, permiten que dicha información se represente de una manera espacial, más amigable y gráfica, consiguiendo el acceso a ella de un mayor número de personas.</div> <div>Es en este punto donde las disciplinas de las geociencias comienzan a tener preponderancia al momento de identificar, ubicar, cuantificar y representar de manera clara y precisa,&nbsp;la información&nbsp;disponible,&nbsp;por lo que</div> <div>no resulta difícil de entender que disciplinas como la geoestadística, geografía, cartografía,&nbsp;geomensura, geomática, entre otras, aporten desde sus particulares perspectivas&nbsp;en el análisis&nbsp;de&nbsp;la información obtenida,</div> <div>permitiendo con ello entregar una mirada distinta a los métodos tradicionales de análisis en busca de la optimización en la toma de decisiones.</div> </div> </div> <div class="page" data-page-number="3" data-loaded="true">&nbsp;</div> Instituto Geográfico Militar ##submission.copyrightStatement## Thu, 31 Dec 2020 00:00:00 -0300