The Mapping and Characterization of Product and Recreation Ecosystem Services in the Nahuelbuta Mountain Range

Ecosystem services are the benefits that people derive from natural ecosystems. The characterization and quantification of ecosystem services contribute to the sustainable management of natural resources. Forests are ecosystems that provide multiple services, including non-timber forest product provision services and cultural recreation services. In this context, the study focused on the analysis and evaluation of the ecosystem services of the Cordillera de Nahuelbuta through the mapping and quantification of these services. We analyzed how the degree of naturalness of forest formations influences the generation of these services. The stock of non-timber forest products was estimated by concentrating on fruits, seeds and fungi. The results show that the area harbors up to 36 species that provide non-timber forest products in the forested areas of the temperate mixed forest of Nahuelbuta of Nothofagus dombeyi and N. obliqua and the coastal temperate laurifolius of Aextoxicon punctatum and Laurelia sempervirens. In relation to the recreation service, there was a high potential for recreation and ecotourism in the area, especially the sectors of Caramávida, Trongol and Nahuelbuta National Park which present an appropiate combination of attributes for recreation such as singular resources, scenic beauty, accessibility and tourism attractiveness. The results reveal the need for an urgent and adequate protection of those core areas where the largest provision of the analyzed ecosystem services is concentrated

Assessment of the IMERG Early-Run Precipitation Estimates over South American Country of Chile

Accurate rainfall measurement is a challenge, especially in regions with diverse climates and complex topography. Thus, knowledge of precipitation patterns requires observational networks with a very high spatial and temporal resolution, which is very difficult to construct in remote areas with complex geological features such as desert areas and mountains, particularly in countries with high topographical variability such as Chile. This study evaluated the performance of the near-real-time Integrated Multi-satellite Retrievals for GPM (IMERG) Early product throughout Chile, a country located in South America between 16°S–66°S latitude. The accuracy of the IMERG Early was assessed at different special and temporal scales from 2015 to 2020. Relative Bias (PBIAS), Mean Absolute Error (MAE), and Root-Mean-Squared Error (RMSE) were used to quantify the errors in the satellite estimates, while the Probability of Detection (POD), False Alarm Ratio (FAR), and Critical Success Index (CSI) were used to evaluate product detection accuracy. In addition, the consistency between the satellite estimates and the ground observations was assessed using the Correlation Coefficient (CC). The spatial results show that the IMERG Early had the best performance over the central zone, while the best temporal performance was detected for the yearly precipitation dataset. In addition, as latitude increases, so do errors. Also, the satellite product tends to slightly overestimate the precipitation throughout the country. The results of this study could contribute towards the improvement of the IMERG algorithms and open research opportunities in areas with high latitudes, such as Chile

Mapeo y caracterización servicio ecosistémico de provisión y recreación en la cordillera de Nahuelbuta (37º30’’ - 38º00’’ Sur)

Ecosystem services are the benefits that people derive from natural ecosystems. The characterization and quantification of ecosystem services contribute to the sustainable management of natural resources. Forests are ecosystems that provide multiple services, including non-timber forest product provision services and cultural recreation services. In this context, the study focused on the analysis and evaluation of the ecosystem services of the Cordillera de Nahuelbuta through the mapping and quantification of these services. We analyzed how the degree of naturalness of forest formations influences the generation of these services. The stock of non-timber forest products was estimated by concentrating on fruits, seeds and fungi. The results show that the area harbors up to 36 species that provide non-timber forest products in the forested areas of the temperate mixed forest of Nahuelbuta of Nothofagus dombeyi and N. obliqua and the coastal temperate laurifolius of Aextoxicon punctatum and Laurelia sempervirens. In relation to the recreation service, there was a high potential for recreation and ecotourism in the area, especially the sectors of Caramávida, Trongol and Nahuelbuta National Park which present an appropiate combination of attributes for recreation such as singular resources, scenic beauty, accessibility and tourism attractiveness. The results reveal the need for an urgent and adequate protection of those core areas where the largest provision of the analyzed ecosystem services is concentrated.Los servicios ecosistémicos son los beneficios que las personas obtienen de los ecosistemas naturales. La caracterización y cuantificación de los servicios ecosistémicos contribuyen a la gestión sustentable de los recursos naturales. Los bosques son ecosistemas que otorgan múltiples servicios, entre los que se destacan servicios de provisión de productos forestales no maderables y servicios culturales de recreación. En este contexto el estudio se enfocó en el análisis y evaluación de los servicios ecosistémicos de la Cordillera de Nahuelbuta a través del mapeo y cuantificación de dichos servicios. Se analizó cómo influye el grado de naturalidad de las formaciones boscosas en la generación de estos servicios. Se estimó el stock de productos forestales no maderables concentrándose en frutos, semillas y hongos. Los resultados arrojan que el área alberga hasta 36 especies que proveen productos forestales no maderables en las formaciones boscosas de Bosque mixto templado de Nahuelbuta de Nothofagus dombeyi y N. obliqua y el Bosque laurifolio templado costero de Aextoxicon punctatum y Laurelia sempervirens. En relación al servicio de recreación se estimó un alto potencial de recreación y ecoturismo en la zona, en especial los sectores de Caramávida, Trongol y Parque Nacional Nahuelbuta los cuales presentan una adecuada combinación de atributos para la recreación tales como recursos singulares, belleza escénica, accesibilidad y capacidad de atracción turística. Los resultados revelan la necesidad de una urgente y adecuada protección de aquellas áreas núcleos en donde se concentra la mayor provisión de los servicios ecosistémicos analizados

Respuesta hidrológica de una cuenca de meso escala frente a futuros escenarios de expansión forestal

A global level more than half of the water generated through the process of runoff is used by man. In south-central Chile the watersheds have been subjected to intensive processes of land use changes, including expansion of forest plantations with exotic species. This study evaluates the hydrological effects of future scenarios for forest expansion in a basin of mesoscale (4.340 km2) using the SWAT model. The scenarios were constructed through logistic regression model forest development planning to the years 2018, 2028 and 2038. The results of the validation process show that the model has good capacity to represent the hydrology of the watershed under analysis. Simulations indicate a decreasing trend in flows especially in the dry season. For some scenarios, decreasing summer flows exceed 50% respect to the base period. This decreasing trend is consistent with those reported by other authors in basins of small and meso-scale.A nivel global más de la mitad del agua generada a través del proceso de escorrentía es usada por el hombre. En el centro-sur de Chile las cuencas hidrográficas han sido sometidas a intensas transformaciones territoriales, incluyendo la forestación masiva con especies exóticas. Este estudio evalúa el efecto hidrológico de futuros escenarios de expansión forestal en una cuenca de meso escala (4.340 km²) utilizando el modelo SWAT. Los escenarios fueron construidos a través del modelo de regresión logística proyectando el desarrollo forestal hacia los años 2018, 2028 y 2038. Los resultados muestran una tendencia a la disminución de los caudales, especialmente en la época de estiaje. Para algunos escenarios la disminución de los caudales de verano supera el 50% respecto al periodo base. Esta tendencia decreciente de los caudales, producto del aumento de la cobertura forestal, es consistente con la reportada por otros autores en cuencas de pequeña y meso-escala

Evaluación de desempeño de métodos de relleno de datos pluviométricos en dos zonas morfoestructurales del Centro Sur de Chile

Una de las principales preocupaciones de los científicos al trabajar con datos temporales es la calidad de la información. Los datos meteorológicos, que son entradas de modelos y predicciones hidroclimáticas, generalmente carecen de series completas. El uso de técnicas de relleno frecuentemente ignora las características orográficas del área de estudio y la precisión del método, produciendo alteraciones en los resultados con importantes consecuencias. El objetivo de este trabajo es evaluar los métodos de relleno de datos pluviométricos razón normal y modelo de regresión lineal (LRM, por sus siglas en inglés), por medio de un análisis del error de estimación aplicado a un registro de 32 años de precipitaciones en dos unidades morfoestructurales distintas localizadas en la región del Biobío, Centro Sur de Chile: la planicie costera y el valle central. Los resultados evidenciaron que el método de Razón Normal presenta menor variabilidad en los errores de estimación y una mejor aproximación a los datos reales para ambas zonas

Una revisión de inundaciones fluviales en Chile, período 1574-2012: causas, recurrencia y efectos geográficos

A literature review of river floods from 1574 to 2012, allows us to analyze and identify the causes or trigger factors, recurrence periods, spatial distribution and geographical effects of flooding within continental Chile. Five types of flooding are identified, based on the triggering factor: volcanic processes, snow/glacial processes, landslides, anthropic interventions and rainfalls. Rainfall is responsible for 71% of flooding events during the period studied. We were able to spatial patterns at a national level, allowing us to define five homogenous zones. The area with the most frequent events corresponds to the Mediterranean climatic domain, which has been characterized by intense storms and environmental changes over the last three decades. An increase in catastrophic flooding from the second half of the 20th century to the present was observed, primarily associated with nivo-glacial processes and human interventions.Una revisión bibliográfica de inundaciones fluviales históricas en el período 15742012 a través de diferentes publicaciones, permite analizar, explicar y sistematizar causas o factores detonantes, periodos de recurrencia, distribución y efectos geográficos de las inundaciones acaecidas en Chile continental. Según el factor detonante se identifican 5 tipos principales de inundaciones asociadas a: procesos volcánicos, procesos nivoglaciares, deslizamientos, intervenciones antrópicas y precipitaciones; estas últimas causan el 71% de las inundaciones en el período analizado. A nivel nacional, se observa un patrón zonal de los tipos de eventos dividido en 5 áreas homogéneas, cuya mayor recurrencia se concentra en el dominio climático mediterráneo, consistente con montos pluviométricos intensos y cambios ambientales ocurridos durante las últimas tres décadas. Se constata un incremento de inundaciones catastróficas, relacionadas principalmente con procesos nivoglaciares e intervenciones antrópicas, desde la segunda mitad del siglo XX a la fecha

Assessment of Future Land Use/Land Cover Scenarios on the Hydrology of a Coastal Basin in South-Central Chile

Land use and land cover (LULC) change is one of the clearest representations of the global environmental change phenomenon at various spatial and temporal scales. Chile is worldwide recognized to have areas dedicated to non-native forest plantations that specifically in coastal range show high environmental and economic deterioration, questioning the sustainability of the forestry industry. Currently, there are no studies in Chile that reveal the real effects of the LULC change on the water balance at basin or sub-basin scales associated with future scenarios, which might contribute to territorial decision-making and reveal the real magnitude of the effects of these dynamics. In this study, in order to study LULC dynamics in a coastal basin in South-Central Chile, we assessed and analyzed the effects of future LULC change scenarios on the hydrological processes by generating future synthetic land cover maps from Landsat (Landsat 5 TM and Landsat 8 OLI) image datasets. The hydrological model Soil Water Assessment Tool (SWAT) was calibrated and validated, using hydroclimatic time series, to simulate discharges and other hydrological components over those future LULC scenarios. The LULC future scenarios were projected using combined Markov chain analysis (CA–Markov) and cellular automata algorithms for the near (2025), middle (2035) and far (2045) future. The results revealed that the effects on the different components of the water balance of the basin are not as significant except in the soil water transfer in percolation (increase 72.4%) and groundwater flow (increase 72.5%). This trend was especially observed in sub-basins with non-native forest plantations that dominated land cover in the year 2035, in which an increase of 43.6% in percolation and groundwater flows resulted in increased aquifer recharge and water storage, mainly offset by a decrease of 27% in the evapotranspiration. This work demonstrates the importance of evaluating the impacts of the dynamics of LULC on the hydrological response of a coastal basin, and also on how the land use governance and policy are closely linked to that of water resources

Vulnerable areas determination based on seismic response at Chile center region

Chile is one of most seismic countries in the world. In the past 100 years, more than 8 major seismic events occurred in Chile, with the coastal area of central Chile being one of the most affected Since 2007, nearly 2,306 earthquakes were recorded in this area with magnitudes varying between 1.9 and 6.9 in the Ritcher and Mercalli scales. The earthquakes’ impact on the engineering structures depends on several factors, such as: the depth of the wave, wave type, geomorphological aspects of the rock, and soil properties. Chile central region of is a very important economics area, but at the same time, very vulnerable. The cities existing on this area, are installed in coastal plains, limited by Coastal Mountains and Pacific Ocean. Most of the seismic activity episodes recorded by Nacional Seismological center (CSN) is on the ocean. The present research aims to identify the regions vulnerable to significant seismic activities based on the average shear wave velocity on the upper 30m (Vs30) and using Geographic Information Systems. The Vs30 values were measured by the United Stated Geological Service (USGS). This analysis is based on the topography, geological units classified by Chilean norms NCh433, NCh2369, and law decree 61/ 2011. The analysis indicated that last epicenter city, Cobquecura, is the low vulnerable area, considering high Vs30 values and low number of habitants. Cities as Concepción, Talcachuano, San Pedro de la Paz, Coronel y Hualpén are more vulnerable because low Vs30 values, and high population. This factor can be associated to river mouths and floodplains presents in this area

Urban growth patterns in the Chilean Patagonia: the case of Coyhaique city

State policies and real estate market destined to people with more economic power, have orientated the recent development of many Chilean cities, reinforcing old urban patterns and creating new ones. Even though these processes have been described and analyzed for many cities and metropolitan areas of Central Chile, there hasn’t been enough evidence about the urban development in Southern Chilean cities; such is the case of Coyhaique, located in Chilean Patagonia. From this perspective this work aims to identify and analyze the urban growth patterns in the city, in a territorial context characterized, besides other aspects, for geographical fragmentation, isolation, dispersion of towns and concentration of population, services and facilities inside the regional capital. The urban growth pattern was analyzed using historical reviews about the evolution since the foundation in 1929. The methods used were GIS and photo interpretation of satellite images of different periods. Finally, urban growth estimation was made based on technical studies.Las políticas de Estado junto con la importante oferta/demanda de productos inmobiliarios para población de mayor ingreso han orientado el desarrollo reciente de varias ciudades chilenas, originando nuevas formas urbanas. Si bien estos procesos han sido descritos y analizados para varias ciudades y áreas metropolitanas de Chile central, no existen suficientes antecedentes empíricos que den cuenta de la realidad del desarrollo urbano de las ciudades más australes del país, como el caso de Coyhaique en la Patagonia chilena. Este trabajo pretende identificar y analizar los patrones de urbanización de esta ciudad, en un contexto territorial caracterizado, entre otros aspectos, por la fragmentación geográfica, el aislamiento, dispersión de los centros poblados y concentración de la población en la capital regional. Se analiza la evolución y factores explicativos que dan cuenta de su rápido proceso de urbanización y, sobre la base de documentos técnicos, históricos y geográficos, se presentan estimaciones futuras del crecimiento de la ciudad