Estimation of chlorophyll-a concentration using Landsat 8 in the Cassaffousth reservoir

The physico-chemical and biological composition of a reservoir's effluents directly influences water quality. The values of variables such as high values of concentrations of chlorophyll-a (Chl-a) are indicators of pollution. The objective of this work was to monitor the trophic status and water quality of the Cassaffousth reservoir (Córdoba, Argentina) through the development of statistical models based on field data and satellite information. During 2016 and 2017, samples were taken bimonthly. Seven sampling sites were selected and physico-chemical and biological parameters were assessed. By using regression techniques, Landsat 8 information was related with field data to construct and validate a statistical model to determine the distribution of Chl-a in the reservoir (R2 = 0.87). The generated algorithm was used to generate maps which contained information about the dynamics of Chl-a in the entire reservoir. Remote sensing techniques can be used to expand the knowledge of the dynamics of the Cassaffousth reservoir. Moreover, these techniques can be used as baselines for the development of an early warning system for this and other reservoirs in the region.Fil: Ledesma, María Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Estudios Básicos y Agropecuarios; ArgentinaFil: Bonansea, Matias. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; ArgentinaFil: Ledesma, Claudia. Universidad Nacional de Río Cuarto; ArgentinaFil: Rodríguez, Claudia. Universidad Nacional de Río Cuarto; ArgentinaFil: Carreño, Joel. Universidad Nacional de Río Cuarto; ArgentinaFil: Pinotti, Lucio Pedro. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; Argentin

Granitos anatécticos de las Sierras Pampeanas de Córdoba (Argentina): edades U-Pb SHRIMP y estudio LAICP- MS de elementos traza en circón de metamorfismo y cristalización diacrónicos

In this contribution we present new U-Pb SHRIMP ages and in situ LA-ICP-MS trace element geochemistry of zircon crystals from the Río de los Sauces anatectic granite, Córdoba, Argentina. Notable difference in texture and composition allowed us to identify two zircon populations in a single granite sample that are interpreted as reflecting metamorphic and igneous origins. Zircons regarded as restitic crystals entrained during the melt segregation yielded a slightly older concordia age of 537.1 ± 4.8 Ma (2σ) than those interpreted as igneous, dated at 529 ± 6 (2σ) Ma. Inherited metamorphic zircons are interpreted to represent solid-state growth during high temperature metamorphism of the Pampean orogeny at the onset of the anatexis or metamorphic peak. By contrast, igneous zircons would record the crystallization age of Zr within the Río de los Sauces granite. The textural, compositional and geochronological data of both zircon populations suggest that the inception of the anatexis, the melt segregation and crystallization occurred during a short period of time of 8 myEn este trabajo se aportan nuevos datos de edades U-Pb SHRIMP y análisis in situ LA-ICP-MS de elementos traza de circones provenientes del granito Río de los Sauces, Córdoba, Argentina. A partir de marcadas diferencias texturales y composicionales se pudieron identificar dos poblaciones de circones en una misma muestra del granito, las cuales sugieren orígenes metamórficos e ígneos. Las edades concordia obtenidas en los circones metamórficos e ígneos fueron de 537,1 ± 4,8 Ma (2σ) y 529 ± 6 (2σ) Ma, respectivamente. Se interpreta que los circones metamórficos representan el crecimiento en estado sólido durante el metamorfismo de alta temperatura de la orogenia Pampeana, durante el inicio o el clímax de la anatexia. Por su parte, las edades de los circones ígneos representan la edad de cristalización del granito Río de los Sauces. Los datos texturales, composicionales y geocronológicos de ambas poblaciones de circones sugieren que el inicio de la anatexia, la segregación del fundido y la cristalización ocurrieron durante un periodo breve de tiempo de 8 ma

Evaluating the feasibility of using Sentinel-2 imagery for water clarity assessment in a reservoir

The new Sentinel-2 satellites present a significant scientific opportunity for the study of water quality. The objective of this study was to evaluate the suitability of Sentinel-2 imagery for estimating and mapping Secchi disk transparency (SDT) in Río Tercero reservoir (Córdoba-Argentina). Field observations and a dataset of atmospherically corrected Sentinel-2 images were used to generate and validate an algorithm to estimate water clarity in the studied reservoir. As a real application of the used methodology, the validated algorithm was used to obtain a spatial representation of water clarity in the reservoir during sampling campaigns. Results demonstrate capabilities of Sentinel-2 mission to make a substantial contribution to the current assessment and understanding of aquatic systems by estimating and mapping a water quality characteristic.Fil: Bonansea, Matias. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Estudios Básicos y Agropecuarios; ArgentinaFil: Ledesma, Micaela. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Estudios Básicos y Agropecuarios; ArgentinaFil: Bazán, Raquel. Universidad Nacional de Córdoba; ArgentinaFil: Ferral, Anabella. Comision Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: German, Alba. Comision Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentina. Ministerio de Agua, Ambiente y Servicios Públicos. - Gobierno de la Provincia de Cordoba. Ministerio de Agua, Ambiente y Servicios Publicos.; ArgentinaFil: O Mill, Patricia. Universidad Nacional de Córdoba; Argentina. Ministerio de Agua, Ambiente y Servicios Públicos. - Gobierno de la Provincia de Cordoba. Ministerio de Agua, Ambiente y Servicios Publicos.; ArgentinaFil: Rodriguez, Claudia. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria. Departamento de Estudios Básicos y Agropecuarios; ArgentinaFil: Pinotti, Lucio Pedro. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; Argentina. Universidad Nacional de Córdoba; Argentin

Evaluación de la capacidad biocontroladora de Trichoderma sp. en un cultivo de garbanzo (Cicer arietinum) en la región semiárida de la Provincia de Córdoba

Trabajo Final Integrador (Área de Consolidación Sistemas Agrícolas de Producción Extensivos - Ingeniería Agrónomica) -- UNC- Facultad de Ciencias Agropecuarias, 2018En este trabajo se busca evaluar la capacidad biocontroladora de Trichoderma sp. en un cultivo de garbanzo (Cicer arietinum) en la región semiárida de la provincia de Córdoba. Además, con diferentes formas de aplicación del mismo. Trichoderma spp es un agente biocontrolador fúngico y un estimulante vegetal el cual surge como una alternativa al uso de agroquímicos. Para el estudio se llevó acabo un ensayo experimental con diseño en bloques, en macroparcelas con 3 surcos por tratamiento de 150 metros de longitud y testigos apareados. Los tratamientos consisten en: Semilla Chorreada con Trichoderma sp.; Semilla con Biopolímero; Semilla Testigo; Semilla con Trichoderma sp.; Semilla con Fungicida; Semilla con Trichoderma sp + Chorreado con Trichoderma sp. Durante el transcurso de la prueba se fueron evaluando distintos parámetros como porcentaje de germinación, altura de plántula, plantas por metro cuadrado, incidencia de enfermedades, rendimiento y calibre. Realizados en sucesivas visitas al campo, complementando todo esto con test a laboratorio. Del trabajo se concluyó que el encapsulado de Tirchoderma en semillas con el biopolímero mejoró los parámetros fisiológicos de tamaño de plantas y rendimiento, posicionando al mismo de manera competitiva con respecto al tratamiento con fungicida

Assessing land use and land cover change in Los Molinos reservoir watershed and the effect on the reservoir water quality

Understanding and modelling land use and land cover (LULC) change have become one of the major subjects of interest for environmental management due to the negative effects that human activities generate on the normal functioning and dynamics of freshwater resources. Remote sensing and geographic information systems (GIS) are essential tools for assessing the drivers that cause LULC change and its relationship with lake and reservoir water quality. The objective of this study was to assess the spatial and temporal dynamics of LULC change in the watershed of Los Molinos reservoir (Argentina), and to investigate its relationship with the reservoir's water quality. Four Landsat imagery was used to analyse the LULC change in the studied watershed and in different buffer zones from 1990 to 2020. Further, the Normalized Difference Vegetation Index (NDVI) derived from a MODIS time-series dataset (2001–2020) was used to explain the effects of LULC change on the status of the reservoir. Results showed that the most significant LULC change started two decades ago and it has intensified during the last ten years. This change is related to the intensification of agriculture activities, and to the increasing conversion into urban areas, mainly on the shores of Los Molinos reservoir. During the period 2010–2020, urbanization located in the 1 km buffer zone defined from the shore of the reservoir increased at an annual rate of 18.02%. The degradation trend of LULC in Los Molinos watershed significantly contributed to the degradation of water quality of the reservoir. This was corroborated by analysing the MODIS NDVI time-series, which showed that since 2014 the NDVI trend-line presented an increasing behaviour and extreme values of NDVI, related to algal blooms, were more frequently observed.Fil: Bonansea, Matias. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Bazán, Raquel del Valle. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; ArgentinaFil: German, Alba. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; ArgentinaFil: Ferral, Anabella. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; ArgentinaFil: Beltramone, Giuliana Beatriz. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cossavella, Ana Maria. Universidad Nacional de Córdoba; ArgentinaFil: Pinotti, Lucio Pedro. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente; Argentin

Magma chamber growth models in the upper crust: A review of the hydraulic and inertial constraints

Finite volumes of magma moving in confinement, store hydraulic potential energy for the generation, control and transmission of power. The Pascal´s principle in a hydraulic jack arrangement is used to model the vertical and lateral growth of sills. The small input piston of the hydraulic jack is equivalent to the feeder dike, the upper large expansible piston equivalent to the magmatic chamber and the inertial force of the magma in the dike is the input force. This arrangement is particularly relevant to the case of sills expanding with blunt tips, for which rapid fracture propagation is inhibited. Hydraulic models concur with experimental data that show that lateral expansion of magma into a sill is promoted when the vertical ascent of magma through a feeder dike reaches the bottom contact with an overlying, flat rigid-layer. At this point, the magma is forced to decelerate, triggering a pressure wave through the conduit caused by the continued ascent of magma further down (fluid-hammer effect). This pressure wave can provide overpressure enough to trigger the initial hydraulic lateral expansion of magma into an incipient sill, and still have enough input inertial force left to continue feeding the hydraulic system. The lateral expansion underneath the strong impeding layer, causes an area increase and thus, further hydraulic amplification of the input inertial force on the sides and roof of the incipient sill, triggering further expansion in a self-reinforcing process. Initially, the lateral pressure increase is larger than that in the roof allowing the sill to expand. However, expansion eventually increases the total integrated force on the roof allowing its uplift into either a laccolith, if the roof preserves continuity, or into a piston bounded by a circular set of fractures. Hydraulic models for shallow magmatic chambers, also suggest that laccolith-like intrusions require the existence of a self-supported chamber roof. In contrast, if the roof of magmatic chambers loses the self-supporting capacity, lopoliths and calderas should be expected for more or less dense magmas, respectively, owing to the growing influence of the density contrast between the host rock and the magma.Fil: Aragon, Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: D'eramo, Fernando Javier. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente.; ArgentinaFil: Pinotti, Lucio Pedro. Universidad Nacional de Río Cuarto; ArgentinaFil: Demartis, Manuel. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente.; ArgentinaFil: Tubía Martinez, José María. Universidad del Pais Vasco - Euskal Herriko Unibertsitatea, Campus Bizkaia;Fil: Weinberg, Roberto F.. Monash University; AustraliaFil: Coniglio, Jorge Enrique. Universidad Nacional de Río Cuarto; Argentin

Utilización de imágenes ASTER y Landsat para el monitoreo de la concentración de clorofila-a en el embalse Los Molinos, Córdoba, Argentina

La detección remota se puede utilizar como una herramienta complementaria en el monitoreo de la calidad del agua de los ecosistemas acuáticos. El objetivo de este estudio fue desarrollar modelos para estimar la distribución espacial de la concentración de clorofila-a (Chl-a) en el reservorio de Los Molinos utilizando imágenes Landsat 7 ETM + y ASTER. El embalse de Los Molinos (32 º 49 'S, 64 º 32' W) es un sistema de usos múltiples utilizado como la segunda fuente de suministro de agua para la ciudad de Córdoba. Los parámetros físicos, químicos y biológicos se midieron en el cuerpo de agua coincidiendo con el paso de los satélites por el área de estudio. Usando diferentes técnicas estadísticas, la información satelital se relacionó con los algoritmos de obtención de datos de campo que mejor explicaban la distribución de Chl-a. Estos modelos se validaron y se usaron para construir mapas que brindan información espacialmente rica sobre los patrones de calidad del agua en todo el reservorio. Ambos sensores podrían ser utilizados para la monitorización de Chl-a. El sensor ASTER, con una resolución espacial más alta que ETM +, mostró una mejor relación entre los datos de Chl-a observados y estimados, lo que permite una mejor discriminación de la variación espacial del parámetro analizado. Los modelos generados pueden proporcionar una base para planificar el monitoreo futuro de la calidad del agua en diferentes cuerpos de agua.Remote sensing can be used as a complementary tool in water quality monitoring of aquatic ecosystems. The aim of this study was to develop models to estimate the spatial distribution of chlorophyll-a concentration (Chl-a) in Los Molinos reservoir using Landsat 7 ETM + and ASTER imagery. Los Molinos reservoir (32 º 49 ‘S, 64 º 32’ W) is a multipurpose system used as the second source of water supply for Córdoba’s city. Physical, chemical and biological parameters were measured in the water body coinciding with the passage of the satellites by the study area. Using different statistical techniques, satellite information was related to field data obtaining algorithms that best explained the distribution of Chl-a. These models were validated and used to construct maps providing spatially rich information on patterns of water quality throughout the reservoir. Both sensors could be used for Chl-a monitoring. ASTER sensor, with higher spatial resolution that ETM+, showed a better relationship between observed versus estimated Chl-a data allowing a better discrimination of the spatial variation of the analysed parameter. The gene

Granite emplacement by crustal boudinage: example of the Calmayo and El Hongo plutons (Córdoba, Argentina)

This study deals with the structure and emplacement of the Calmayo and El Hongo trondhjemite plutons (Famatinian belt of Córdoba, Argentina). It provides structural data from the granites and the country rocks and a study of the magnetic fabric in the plutons. New U/Pb geochronological data yield intrusion ages of 512.1 ± 3.4 Ma and 500.6 ± 4.5 Ma for the Calmayo and El Hongo plutons respectively. The El Hongo massif and the southern part of the Calmayo trondhjemite preserve magmatic structures, whereas the northern domain of Calmayo shows the imprint of solid-state deformation. The main foliation in the country rocks outlines a boudin-like pattern at the map scale and the granites are located along boudin necks, suggesting that the emplacement of these trondhjemite plutons was linked to large-scale boudinage of the country rocks.Fil: D'eramo, Fernando Javier. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tubía, José M.. Universidad del País Vasco; EspañaFil: Pinotti, Lucio Pedro. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vegas, Néstor. Universidad del País Vasco; EspañaFil: Coniglio, Jorge Enrique. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Demartis, Manuel. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aranguren, Aitor. Universidad del País Vasco; EspañaFil: Basei, Miguel. Universidade de Sao Paulo; Brasi

Top-down structures of mafic enclaves within the Valle Fértil magmatic complex (Early Ordovician, San Juan, Argentina)

Magmatic structures related to the mechanical interaction between mafic magmas and granitoids have been studied in the Valle Fértil calc-alkaline igneous complex, Argentina. Excepcional outcrops with vertical walls of more than 300 m high allow us the study of three-dimensional geometries of individual blobs of mafic magma as well as the geometry of pipe-like structures in which mafic microgranular enclaves are concentrated in more than 50 times the normal abundance in the granodiorite mass. The shape of enclaves and pipe-like structures are interpreted as the ressult of top-to-down intrusions of a mafic magma into a granodiorite-tonalite mass. These sinking structures are the result of a reverselly stratified magma chamber with gabbros and diorites at the top and granodiorite-tonalite at the bottom. They may account for most of the structures found in microgranular enclaves and magma mingling zones that characterize calc-alkaline batholiths. Synplutonic intrusions from the top is the only plausible mechanism to account for the observed structures. The model may be of general application to calc-alkaline batholiths characterized by the presence of mafic microgranular enclaves. An implication of these reverselly stratified magma chambers is the presence of a petrological inversion which may be the consequence of cold diapirs emplaced below the mantle wedge in a suprasubduction setting

The westward lithospheric drift, its role on the subduction and transform zones surrounding Americas: Andean to Cordilleran orogenic types cyclicity

We investigate the effect of the westerly rotation of the lithosphere on the active margins that surround the Americas and find good correlations between the inferred easterly-directed mantle counterflow and the main structural grain and kinematics of the Andes and Sandwich arc slabs. In the Andes, the subduction zone is shallow and with low dip, because the mantle flow sustains the slab; the subduction hinge converges relative to the upper plate and generates an uplifting doubly verging orogen. The Sandwich Arc is generated by a westerly-directed SAM (South American) plate subduction where the eastward mantle flow is steepening and retreating the subduction zone. In this context, the slab hinge is retreating relative to the upper plate, generating the backarc basin and a low bathymetry single-verging accretionary prism. In Central America, the Caribbean plate presents a more complex scenario: (a) To the East, the Antilles Arc is generated by westerly directed subduction of the SAM plate, where the eastward mantle flow is steepening and retreating the subduction zone. (b) To the West, the Middle America Trench and Arc are generated by the easterly-directed subduction of the Cocos plate, where the shallow subduction caused by eastward mantle flow in its northern segment gradually steepens to the southern segment as it is infered by the preexisting westerly-directed subduction of the Caribbean Plateau.In the frame of the westerly lithospheric flow, the subduction of a divergent active ridge plays the role of introducing a change in the oceanic/continental plate's convergence angle, such as in NAM (North American) plate with the collision with the Pacific/Farallon active ridge in the Neogene (Cordilleran orogenic type scenario). The easterly mantle drift sustains strong plate coupling along NAM, showing at Juan de Fuca easterly subducting microplate that the subduction hinge advances relative to the upper plate. This lower/upper plate convergence coupling also applies along strike to the neighbor continental strike slip fault systems where subduction was terminated (San Andreas and Queen Charlotte). The lower/upper plate convergence coupling enables the capture of the continental plate ribbons of Baja California and Yakutat terrane by the Pacific oceanic plate, transporting them along the strike slip fault systems as para-autochthonous terranes. This Cordilleran orogenic type scenario, is also recorded in SAM following the collision with the Aluk/Farallon active ridge in the Paleogene, segmenting SAM margin into the eastwardly subducting Tupac Amaru microplate intercalated between the proto-Liquiñe-Ofqui and Atacama strike slip fault systems, where subduction was terminated and para-autochthonous terranes transported. In the Neogene, the convergence of Nazca plate with respect to SAM reinstalls subduction and the present Andean orogenic type scenario