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Drought propagation in semi-arid river basins in Latin America: Lessons from Mexico to the Southern Cone

Año: 2018
Categoría: Cuenca del Maipo, Seguridad hídrica, Sequía

Título publicación

Drought propagation in semi-arid river basins in Latin America: Lessons from Mexico to the Southern Cone

Autores: Oertel, M., Meza, F.J., Gironás, J., Scott, C; Rojas, F. Pineda, N.

Revista: Water (2018) 10 (11)

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Abstract

Detecting droughts as early as possible is important in avoiding negative impacts on economy, society, and environment. To improve drought monitoring, we studied drought propagation (i.e., the temporal manifestation of a precipitation deficit on soil moisture and streamflow). We used the Standardized Precipitation Evapotranspiration Index (SPEI), Standardized Streamflow Index (SSI), and Standardized Soil Moisture Index (SSMI) in three drought-prone regions: Sonora (Mexico), Maipo (Chile), and Mendoza-Tunuyán (Argentina) to study their temporal interdependence.

Spatio-temporal estimation of climatic variables for gap filling and record extension using Reanalysis data

Año: 2018
Categoría: Ciencias atmosféricas, Clima, Modelación climática

Título publicación

Spatio-temporal estimation of climatic variables for gap filling and record extension using Reanalysis data

Autores: David Morales-Moraga, Francisco J. Meza, Jorge Gironás, Marcelo Miranda

Revista: Theoretical and Applied Climatology (2018) https://doi.org/10.1007/s00704-018-2653-8

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Abstract

The availability of reliable meteorological records is crucial for the development of a number of environmental studies. Unfortunately, these records are not always complete, usually show errors and/or have an insufficient length. This paper presents a gap filling and data record extension methodology for minimum temperature, maximum temperature, and precipitation.

Decomposition of 2D polygons and its effect in hydrological models

Año: 2018
Categoría: Hidrología, Modelación hidrológica

Título publicación

Decomposition of 2D polygons and its effect in hydrological models

Autores: P. Sanzana, J. Gironás, I. Braud, N. Hitschfeld, F. Branger, F. Rodriguez, M. Fuamba, J. Romero, X. Vargas, J. F. Muñoz, S. Vicuña, A. Mejía

Revista: Journal of Hydroinformatics (2018) - https://doi.org/10.2166/hydro.2018.031

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Abstract

2D non-uniform polygonal meshes allow representation of the impact of landscape elements and small infrastructures on water flows. The initial vectorial mesh, derived from the intersection of several geographical information systems' layers, can have highly non-convex or sliver polygons. These bad-shaped elements compromise accurate numerical flow computation. We propose a flexible divide-and-conquer strategy to decompose polygons into physiographical meaningful parts using shape descriptors to better represent the surface terrain and hydrologic connectivity.

Using a Statistical Preanalysis Approach as an Ensemble Technique for the Unbiased Mapping of GCM Changes to Local Stations

Año: 2018
Categoría: Cambio climático, Clima, Downscaling, Modelación, Modelación climática, Predicción Climática

Título publicación

Using a Statistical Preanalysis Approach as an Ensemble Technique for the Unbiased Mapping of GCM Changes to Local Stations

Autores: Cristián Chadwick, Jorge Gironás, Sebastián Vicuña, Francisco Meza, James McPhee

Revista: Journal of Hydrometeorology (2018) 19: 1447–1465

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Abstract

Accounting for climate change, GCM-based projections and their uncertainty are relevant to study potential impacts on hydrological regimes as well as to analyze, operate, and design water infrastructure. Traditionally, several downscaled and/or bias-corrected GCM projections are individually or jointly used to map the raw GCMs’ changes to local stations and evaluate uncertainty. However, the preservation of GCMs’ statistical attributes is by no means guaranteed, and thus alternative methods to cope with this issue are needed.
 

Exclusion of small mammals and lagomorphs invasion interact with human-trampling to drive changes in topsoil microbial community structure and function in semiarid Chile

Año: 2018
Categoría: Servicios ecosistémicos, Sistemas socio-ecológicos, Medio Ambiente

Título publicación

Exclusion of small mammals and lagomorphs invasion interact with human-trampling to drive changes in topsoil microbial community structure and function in semiarid Chile

Autores: Alfaro, F. D., Manzano, M., Abades, S., Trefault, N., Iglesia, R. de la, Gaxiola, A., Marquet, P., Gutierrez, J., Meserve, P., Kelt, D., Belnap, J., Armesto, J. J.

Revista: Soil Biology and Biochemistry (2018), 124, 1–10

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Abstract

Species losses and additions can disrupt the relationship between resident species and the structure and functioning of ecosystems. Persistent human-trampling, on the other hand, can have similar effects through the disruption of biocrusts on surface soils of semiarid systems, affecting soil stability and fixation of carbon and nitrogen. Here, we tested the interactive and synergistic impacts of the exclusion of native mammalian herbivores and the effects of introduced lagomorphs in a semiarid thorn scrub ecosystem, where soils were subjected to two different trampling intensities (i.e., trampled and non-trampled). We postulated that because of their differential habitat use and fossorial activities, with respect to native small mammals, lagomorphs would have strong negative effects on soil structure, biocrust cover, and biocrust bacterial community structure.

Using the Weather Research and Forecasting (WRF) Model for Precipitation Forecasting in an Andean Region with Complex Topography

Año: 2018
Categoría: Modelación, Modelación climática, MODIS, Ocurrencia de precipitación complejas, Precipitaciones, Predicción Climática

Título publicación

Using the Weather Research and Forecasting (WRF) Model for Precipitation Forecasting in an Andean Region with Complex Topography

Autores: Gonzalo Yáñez-Morroni, Jorge Gironás, Marta Caneo, Rodrigo Delgado, René Garreaud

Revista: Atmosphere (2018), 9(8), 304

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Abstract

The Weather Research and Forecasting (WRF) model has been successfully used in weather prediction, but its ability to simulate precipitation over areas with complex topography is not optimal. Consequently, WRF has problems forecasting rainfall events over Chilean mountainous terrain and foothills, where some of the main cities are located, and where intense rainfall occurs due to cutoff lows.
 

Use of fiber-optic distributed temperature sensing to investigate erosion of the non-convective zone in salt-gradient solar ponds

Año: 2018
Categoría: Estimación Temperatura, Modelación

Título publicación

Use of fiber-optic distributed temperature sensing to investigate erosion of the non-convective zone in salt-gradient solar ponds

Autores: Sarabia, A., Meza, F., Suárez F.

Revista: Solar Energy (2018) 170: 499-509

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Abstract

Salt-gradient solar ponds (SGSPs) collect and store solar radiation as thermal energy. This thermal energy is stored in the pond’s bottom because of the existence of the non-convective zone (NCZ), a layer comprised by a salinity gradient that results in a stable density profile, which suppresses global convection within the pond. As a consequence, the NCZ is the most important layer of an SGSP that must be maintained to sustain the internal structure of the pond and to allow successful thermal energy storage.

Integrating strategic land use planning in the construction of future land use scenarios and its performance: The Maipo River Basin, Chile

Año: 2018
Categoría: Agricultura, Cambio global, Crecimiento urbano, Cuenca del Maipo, Cuencas urbanas, Modelación, Modelo integrado uso de la tierra

Título publicación

Integrating strategic land use planning in the construction of future land use scenarios and its performance: The Maipo River Basin, Chile

Autores:  Lenin Henriquez-Dole, Tomás J. Usón, Sebastián Vicuña, Cristián Henríquez, Jorge Gironás, Francisco Meza

Revista: Land Use Policy 78 (2018): 353:366

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Abstract

The integration of urban, rural, and environmental systems is fundamental for resource management. Strategic land use planning attempts to balance these systems to reach sustainability by incorporating future scenario analyses. However, long-term implications of these strategic land use plans are not easily understood, nor spatially visualized, due to their multidimensional effects. This paper illustrates the integration of political conditionings obtained from a strategic land use plan, into a land change model (LCM) to assess long-term policy impacts using landscape metrics.
 

Soil water content effects on net ecosystem CO2 exchange and actual evapotranspiration in a Mediterranean semiarid savanna of Central Chile

Año: 2018
Categoría: Acacia cavens, Carbono, Evapotranspiración, Servicios ecosistémicos

Título publicación

Soil water content effects on net ecosystem CO2 exchange and actual evapotranspiration in a Mediterranean semiarid savanna of Central Chile

Autores: Meza, F.J., Montes, C., Bravo-Martínez, F., Serrano-Ortiz, P., Kowalski, A.

Revista: Scientific Reports (2018) 8: 8570

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Abstract

Biosphere-atmosphere water and carbon fluxes depend on ecosystem structure, and their magnitudes and seasonal behavior are driven by environmental and biological factors. We studied the seasonal behavior of net ecosystem CO2 exchange (NEE), Gross Primary Productivity (GPP), Ecosystem Respiration (RE), and actual evapotranspiration (ETa) obtained by eddy covariance measurements during two years in a Mediterranean Acacia savanna ecosystem (Acacia caven) in Central Chile.

A rule-based approach for preventive identification of potential conflictive criteria in mining operations in Chile

Año: 2018
Categoría: Impactos, Planificación territorial, Sistemas socio-ecológicos, Vulnerabilidad

Título publicación

A rule-based approach for preventive identification of potential conflictive criteria in mining operations in Chile

Autores: Anahí Ocampo-Melgar, Jorge Gironás, Aida Valls

Revista: Journal of Cleaner Production (2018) 184:559-568

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Abstract

Mining projects, as with many other extractive activities, result in divergent opinions during the planning process which may trigger conflict. Early understanding of stakeholders’ priorities can help with the design of better projects while reducing sources of potential conflict. The objective of this article is to present a rule-based method for decision support to be used in the first stages of the project to identify disagreements in the form of potentially conflictive criteria. The method proposed defines four attributes that should be evaluated for the different relevant criteria subject to potential conflict: the importance of the criterion, the perceived risk, the fairness, and the affected side’s willingness to make dialogue.