Longitudinal connectivity is the main attribute of river ecosystems and is essential for the main... more Longitudinal connectivity is the main attribute of river ecosystems and is essential for the maintenance of aquatic biota. When longitudinal connectivity decreases in a river network, abundance of some fish species decreases, and local extinctions may occur. Such abundance decreases and extinctions affect local assemblage structure (alpha diversity) and result in a high degree of dissimilarity among local assemblages (higher beta diversity). Specific ecological mechanisms that are behind these biodiversity changes induced by connectivity loss remain poorly understood. Here, we assessed the effects of fragmentation at the local and basin level, as well as local environmental variables on local fish diversity patterns in eight Andean river basins in central Chile (32–39° S). The results indicated that fish assemblages inhabiting pool habitats in highly fragmented basins were characterized by significantly lower species richness and alpha diversity mainly driven by absence of fish spec...
Crotalus enyo es una vibora de cascabel endemica de la peninsula de Baja California, Mexico. La h... more Crotalus enyo es una vibora de cascabel endemica de la peninsula de Baja California, Mexico. La historia natural de esta especie es poco conocida, por lo cual el objetivo de este estudio fue determinar la dieta de C. enyo en la Region del Cabo, que presenta condiciones particularmente distintas al resto de la peninsula. Se analizaron los contenidos estomacales de 24 especimenes obtenidos durante 2010-2013, y se identificaron las presas ingeridas. La dieta de C. enyo consiste en roedores (83.34%) y lagartijas (16.66%), y aunque presenta una dieta diversa, los datos sugieren que C. enyo es un depredador especialista en la Region del Cabo. No se encontro diferencia en la composicion de la dieta entre sexos, sitios de captura y temporadas. Este estudio documenta tres nuevos elementos en la dieta de C. enyo : el Huico Garganta Naranja ( Aspidocelis hyperythra), el Garrobo del Cabo ( Ctenosaura hemilopha ) y la Lagartija Espinosa de Hunsaker ( Sceloporus hunsakerii )
Journal of The South African Institute of Mining and Metallurgy, 2002
The Modified Zincexi?½ Process, developed by Ti?½cnicas Reunidas, is highly flexible dealing with... more The Modified Zincexi?½ Process, developed by Ti?½cnicas Reunidas, is highly flexible dealing with a wide range of pregnant leach solutions. No matter if those solutions are produced from primary or secondary raw materials, and/or are based on conventional leaching, pressure leaching, heap leaching or bio leaching the result is always high-purity zinc product. The zinc solvent extraction unit within the process is a very effective barrier for impurities and a buffer for the composition of the pregnant liquor. This unit achieves an extremely pure aqueous extract that can be converted into different final products. All of them are characterized by fulfilling the highest purity standards. Also, there is the possibility to adapt the global process to a wide range of pregnant liquor compositions and various production capacities up to a zinc production limit over 150 000 t/a with a single solvent extraction plant.
Se documenta por primera vez el amplexo heteroespecífico entre Triprion petasatus e Incilius vall... more Se documenta por primera vez el amplexo heteroespecífico entre Triprion petasatus e Incilius valliceps en la localidad de Pisté, Yucatán México. Este comportamiento ha sido documentado con anterioridad en otros anfibios, muchos de ellos también reproductores explosivos que aprovechan los cuerpos de agua temporales, en sitios con una marcada estación de secas.
Intermittent rivers and ephemeral streams (IRES) are increasingly studied because of their often-... more Intermittent rivers and ephemeral streams (IRES) are increasingly studied because of their often-unique aquatic and terrestrial biodiversity, biogeochemical processes and associated ecosystem services. This study is the first to examine the hydrological, physicochemical and taxonomic variability during the dry-wet transition of an intermittent river in the Chilean Mediterranean Zone. Based on 30-years of river monitoring data and the TREHS tool, the hydrology of the river was characterised. Overall, the river shows a significant reduction in streamflow (−0.031 m3/s per year) and a substantial increase of zero flow days (+3.5 days per year). During the transition of hydrological states, variations were observed in the environmental conditions and invertebrate communities. During the drying phase, abundance, richness, and diversity were highest, while species turn-over was highest during base flow conditions. The disconnected pools and the flow resumption phases were characterised by ...
Paleolimnological reconstructions from the mid and high latitudes in the Southern Hemisphere are ... more Paleolimnological reconstructions from the mid and high latitudes in the Southern Hemisphere are still relatively scarce. Anthropogenic impacts have evidenced trophic state changes and an increase in cyanobacterial blooms in the lacustrine system of San Pedro de la Paz in the last decades. Here, we reconstructed primary production and sedimentological changes spanning the past 2500 years in two coastal lakes in Mediterranean Chile. A multiproxy approach including sedimentological, biogenic silica, carbon and nitrogen isotopes and fossil pigments analysis in sediment cores was performed in Laguna Grande (LGSP) and Laguna Chica de San Pedro (LCSP). A marked change in the sedimentology of the lakes, likely related to the terrigenous sediment inputs derived by a transition from an arid condition in the mid-Holocene to a more humid condition in the late Holocene that favoured arboreal forest establishment at 100 BC–AD 150. A period of low primary production was identified between 850 to ...
The most robust evidence indicating that petroleum migrates in the Gulf of Mexico (GoM) is the pr... more The most robust evidence indicating that petroleum migrates in the Gulf of Mexico (GoM) is the presence of oil slicks at the surface of the sea coming from naturally sourced oil at the sea bottom. The mechanisms for oil migration in the GoM involve the interplay of several variables (including faults, pressure, salt diapirism, etc.) These are not fully understood locally, let alone regionally, and are not well constrained to basin evolution. The use of numerical models helps to represent and visualize oil migration from the source to the traps and or seeps but it is limited by the lack of a complete geological picture. However, despite these limitations, numerical models are an important means of estimating the timing of oil migration. Salt movement through time has a huge influence on the patterns of oil migration and re-migration. The underlying geometries of Allochthonous Salt can help focus oil to an up dip trap or in turn result in the breaching of a trap. Subsequent salt withd...
Longitudinal connectivity is the main attribute of river ecosystems and is essential for the main... more Longitudinal connectivity is the main attribute of river ecosystems and is essential for the maintenance of aquatic biota. When longitudinal connectivity decreases in a river network, abundance of some fish species decreases, and local extinctions may occur. Such abundance decreases and extinctions affect local assemblage structure (alpha diversity) and result in a high degree of dissimilarity among local assemblages (higher beta diversity). Specific ecological mechanisms that are behind these biodiversity changes induced by connectivity loss remain poorly understood. Here, we assessed the effects of fragmentation at the local and basin level, as well as local environmental variables on local fish diversity patterns in eight Andean river basins in central Chile (32–39° S). The results indicated that fish assemblages inhabiting pool habitats in highly fragmented basins were characterized by significantly lower species richness and alpha diversity mainly driven by absence of fish spec...
Crotalus enyo es una vibora de cascabel endemica de la peninsula de Baja California, Mexico. La h... more Crotalus enyo es una vibora de cascabel endemica de la peninsula de Baja California, Mexico. La historia natural de esta especie es poco conocida, por lo cual el objetivo de este estudio fue determinar la dieta de C. enyo en la Region del Cabo, que presenta condiciones particularmente distintas al resto de la peninsula. Se analizaron los contenidos estomacales de 24 especimenes obtenidos durante 2010-2013, y se identificaron las presas ingeridas. La dieta de C. enyo consiste en roedores (83.34%) y lagartijas (16.66%), y aunque presenta una dieta diversa, los datos sugieren que C. enyo es un depredador especialista en la Region del Cabo. No se encontro diferencia en la composicion de la dieta entre sexos, sitios de captura y temporadas. Este estudio documenta tres nuevos elementos en la dieta de C. enyo : el Huico Garganta Naranja ( Aspidocelis hyperythra), el Garrobo del Cabo ( Ctenosaura hemilopha ) y la Lagartija Espinosa de Hunsaker ( Sceloporus hunsakerii )
Journal of The South African Institute of Mining and Metallurgy, 2002
The Modified Zincexi?½ Process, developed by Ti?½cnicas Reunidas, is highly flexible dealing with... more The Modified Zincexi?½ Process, developed by Ti?½cnicas Reunidas, is highly flexible dealing with a wide range of pregnant leach solutions. No matter if those solutions are produced from primary or secondary raw materials, and/or are based on conventional leaching, pressure leaching, heap leaching or bio leaching the result is always high-purity zinc product. The zinc solvent extraction unit within the process is a very effective barrier for impurities and a buffer for the composition of the pregnant liquor. This unit achieves an extremely pure aqueous extract that can be converted into different final products. All of them are characterized by fulfilling the highest purity standards. Also, there is the possibility to adapt the global process to a wide range of pregnant liquor compositions and various production capacities up to a zinc production limit over 150 000 t/a with a single solvent extraction plant.
Se documenta por primera vez el amplexo heteroespecífico entre Triprion petasatus e Incilius vall... more Se documenta por primera vez el amplexo heteroespecífico entre Triprion petasatus e Incilius valliceps en la localidad de Pisté, Yucatán México. Este comportamiento ha sido documentado con anterioridad en otros anfibios, muchos de ellos también reproductores explosivos que aprovechan los cuerpos de agua temporales, en sitios con una marcada estación de secas.
Intermittent rivers and ephemeral streams (IRES) are increasingly studied because of their often-... more Intermittent rivers and ephemeral streams (IRES) are increasingly studied because of their often-unique aquatic and terrestrial biodiversity, biogeochemical processes and associated ecosystem services. This study is the first to examine the hydrological, physicochemical and taxonomic variability during the dry-wet transition of an intermittent river in the Chilean Mediterranean Zone. Based on 30-years of river monitoring data and the TREHS tool, the hydrology of the river was characterised. Overall, the river shows a significant reduction in streamflow (−0.031 m3/s per year) and a substantial increase of zero flow days (+3.5 days per year). During the transition of hydrological states, variations were observed in the environmental conditions and invertebrate communities. During the drying phase, abundance, richness, and diversity were highest, while species turn-over was highest during base flow conditions. The disconnected pools and the flow resumption phases were characterised by ...
Paleolimnological reconstructions from the mid and high latitudes in the Southern Hemisphere are ... more Paleolimnological reconstructions from the mid and high latitudes in the Southern Hemisphere are still relatively scarce. Anthropogenic impacts have evidenced trophic state changes and an increase in cyanobacterial blooms in the lacustrine system of San Pedro de la Paz in the last decades. Here, we reconstructed primary production and sedimentological changes spanning the past 2500 years in two coastal lakes in Mediterranean Chile. A multiproxy approach including sedimentological, biogenic silica, carbon and nitrogen isotopes and fossil pigments analysis in sediment cores was performed in Laguna Grande (LGSP) and Laguna Chica de San Pedro (LCSP). A marked change in the sedimentology of the lakes, likely related to the terrigenous sediment inputs derived by a transition from an arid condition in the mid-Holocene to a more humid condition in the late Holocene that favoured arboreal forest establishment at 100 BC–AD 150. A period of low primary production was identified between 850 to ...
The most robust evidence indicating that petroleum migrates in the Gulf of Mexico (GoM) is the pr... more The most robust evidence indicating that petroleum migrates in the Gulf of Mexico (GoM) is the presence of oil slicks at the surface of the sea coming from naturally sourced oil at the sea bottom. The mechanisms for oil migration in the GoM involve the interplay of several variables (including faults, pressure, salt diapirism, etc.) These are not fully understood locally, let alone regionally, and are not well constrained to basin evolution. The use of numerical models helps to represent and visualize oil migration from the source to the traps and or seeps but it is limited by the lack of a complete geological picture. However, despite these limitations, numerical models are an important means of estimating the timing of oil migration. Salt movement through time has a huge influence on the patterns of oil migration and re-migration. The underlying geometries of Allochthonous Salt can help focus oil to an up dip trap or in turn result in the breaching of a trap. Subsequent salt withd...
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Papers by Gustavo Diaz