A5002176368- Plant Water Relations and Carbon Dynamics
- CO2 Sequestration and Geologic Interactions
- Geothermal Energy Systems and Applications
- Soil Science and Environmental Management
- Groundwater flow and contamination studies
- Plant and soil sciences
- Botanical Research and Applications
- Tree-ring climate responses
- Plant Diversity and Evolution
- Ecology and Vegetation Dynamics Studies
- Climate change and permafrost
- Climate variability and models
- Soil Carbon and Nitrogen Dynamics
- Groundwater and Isotope Geochemistry
- Hydraulic Fracturing and Reservoir Analysis
- Groundwater and Watershed Analysis
- Botany and Geology in Latin America and Caribbean
- Forest ecology and management
- Atmospheric and Environmental Gas Dynamics
- Plant Taxonomy and Phylogenetics
- Botany, Ecology, and Taxonomy Studies
- Environmental and Ecological Studies
- Nuclear Engineering Thermal-Hydraulics
- Plant responses to elevated CO2
- Scarabaeidae Beetle Taxonomy and Biogeography
Universitat Politècnica de Catalunya
2021-2023
Consejo Superior de Investigaciones Científicas
2023
Universitat Autònoma de Barcelona
2023
Simón Bolívar University
1992-2019
Universidad de Salamanca
2016-2017
Instituto Venezolano de Investigaciones Científicas
2014
Petroleum of Venezuela (Venezuela)
2014
Baker Hughes (United States)
2011
Ecologists have long sought to understand the factors controlling structure of savanna vegetation. Using data from 2154 sites in savannas across Africa, Australia, and South America, we found that increasing moisture availability drives increases fire tree basal area, whereas reduces area. However, among continents, magnitude these effects varied substantially, so a single model cannot adequately represent woody biomass regions. Historical environmental differences drive regional variation...
Abstract High-temperature aquifer thermal energy storage (HT-ATES) systems can help in balancing demand and supply for better use of infrastructures resources. The aim these is to store high amounts heat be reused later. HT-ATES requires addressing problems such as variations the properties aquifer, losses uplift surface. Coupled thermo-hydro-mechanical (THM) modelling a good tool analyse viability cost effectiveness understand interaction processes, flux, groundwater flow ground...
This work assesses the vulnerability of groundwater to pollution in a zone characterized by fissured aquifers. Information from area was analysed using geographic information systems determine series key parameters: depth water table, net recharge, aquifer-averaged characteristics, soil-averaged topography, impact unsaturated and hydraulic conductivity. Parameter maps are used calculate five different degrees area. Finally, potential environmental impacts human activities map. method...
Atmospheric carbon dioxide (CO2) and ammonia (NH2) exchanges were determined in the Trachypogon savannas of Orinoco Llanos using energy balance approach. Total dry mass separate values plant parts used for a growth analysis community measurements nitrogen content. During period, net assimilation (P40) ranged from 0.102 to 0.127 MJ m−2 d−1 (6.6–7.9 g d−1). These figures similar mean crop rate measured approach (2.8–6.9 Analysis daily trend CO2 assimilated by showed low total conversion...
Land use changes in the savannas of Orinoco lowlands have resulted a mosaic vegetation. To elucidate how these affected carbon exchanges with atmosphere, we measured CO2 fluxes by eddy covariance and soil efflux systems along disturbance gradient beginning cultivated tall-grass Andropogon field (S1) extending over three savanna sites increasing woody cover growing above native herbaceous The included (S2), tree (S3) woodland (S4). During wet season, maximum diurnal net ecosystem exchange...
Detrended Canonical Correspondence Analysis (DCCA) was used to describe the relationship between savanna environments and vegetation community composition in Orinoco Basin. TWINSPAN derived three major types of vegetation, each with its own floristic physiognomic features. The first group reflected a plant association species Trachypogon occurring moderately infertile soils low water availability high bulk density. This is distributed mostly on hilltops dissected plains northern savannas....
The present work envisages the possible geometry of a contaminated plume groundwater near hospital facilities by combining GIS (Geographic Information System) and geophysical methods. rock underlying soil thin sedimentary cover study area is moderately fractured quartzite, which makes aquifers vulnerable to pollution. methodology used calculate that would be affected effluent source residual water, based on algorithms consider ground surface mapping (slopes, orientations, accumulated costs...
Abstract Waterflooding is an improved oil recovery (IOR) method commonly used worldwide. Some of the world's largest waterfloods are found on Lake Maracaibo, in western Venezuela. One such project Bachaquero-02 (Bach-02) which was initiated 1967 as a peripheral water injection unconsolidated sandstone reservoir with average permeability 350 mD and gravity 15° API. This waterflood has been subject various studies that include conventional assessments, integrated full field simulation studies....
In the Orinoco lowlands, savannas have been often replaced by pastures composed of C4 grass, Brachiaria decumbens Stapf. We addressed following questions: (1) How does replacement native vegetation affect CO2 exchange on seasonal and annual scales? (2) do biophysical constraints change when landscape is transformed? To assess how these changes carbon exchange, we determined simultaneously fluxes eddy covariance, soil efflux a chamber-based system in B. herbaceous savanna stands. Measurements...
In order to assess the thermo-hydraulic modelling capabilities of various geothermal simulators, a comparative test suite was created, consisting set cases designed with conditions relevant low-enthalpy range operations within European HEATSTORE research project. an effort increase confidence in usage each simulator, used as benchmark by 10 simulators diverse origin, formulation, and licensing characteristics: COMSOL, MARTHE, ComPASS, Nexus-CSMP++, MOOSE, SEAWATv4, CODE_BRIGHT, Tough3,...
The incidence of termite mounds was determined in twenty-six sites the Trachypogon savannas at Orinoco Llanos, including a wide range physionomic types. A multiple discriminate analysis utilized to analyze ecological variables as best indicators given area's suitability for support terrestrial Velocitermes and/or Nasutitermes species. included physical attributes (texture, ineffective soil mass, water holding capacity, and infiltration rate), chemical (cation exchange base saturation,...
We analyzed the eddy covariance measurements of momentum, mass, and energy taken daily throughout five consecutive seasonal courses (i.e. 840 d after planting) a pineapple [Ananas comosus (L.) Merr. cv. Red Spanish] field growing in Orinoco lowlands. This provides an opportunity for micrometeorological studies because flat windy site; weather including ENSO effects Crassulacean Acid Metabolism (CAM) physiology crop were additional attributes. Soil CO2 flux was quantified added to net...
Bulk precipitation was daily collected and individual pH measured at the Trachypogon savannas, Venezuela, over a consecutive 3-year period. The volume-weighted mean as calculated, were 5.8, 5.6 5.8 for 1981, 1982 1983, respectively. annual variation of ranged from 4.9 to 6.9: 4.8 6.3 5.4 6.8 units in However, this savanna area, which is relatively remote heavy sources industrial pollution, proportion rains with < 5.0, occurring mainly onset end wet season, 2.0,3.0 0.0%
Changes in land use the Orinoco lowlands affect daily trends of energy and water vapor fluxes. We analyzed these fluxes along a disturbance gradient beginning from cultivated tall-grass Andropogon field (S1) extending over three savanna sites with increasing woody cover herbaceous vegetation. The encompass (S2), tree (S3) woodland (S4). In wet season, there were differences radiation budget: seasonally averaged albedo for S1 (0.17) exceeded that S2-S4 (0.13-0.14). Eddy covariance indicate...