Miguel Angel Huerta-Diaz | Universidad Autonoma de Baja California (original) (raw)

Papers by Miguel Angel Huerta-Diaz

Millimeter-scale resolution of trace metal distributions in microbial mats from a hypersaline env... more Millimeter-scale resolution of trace metal distributions in microbial mats from a hypersaline environment in Baja California, Mexico

Frontiers in Marine Science

The Gulf of Mexico (GoM) is one of the most dynamic marginal seas in the world owing to the intru... more The Gulf of Mexico (GoM) is one of the most dynamic marginal seas in the world owing to the intrusion of the Loop Current and the shedding of anticyclonic eddies (LCE) that travel westward across the Gulf. However, the impacts of these mesoscale dynamics on the supply and removal of bioessential trace metals in surface waters remain unclear. We study the impact of mesoscale eddies on the distribution of dissolved nickel (Ni), a biologically active element scarcely studied in the region. The vertical distribution of Ni was determined in the deep-water region of the GoM during summer of 2017, when two anticyclonic LCE (Quantum and Poseidon) were present. Nutrient-like profiles of Ni in the GoM resemble those from the Atlantic Ocean, but they showed high spatial variability within the first 1000 m, which was associated with the impact of mesoscale eddies. Similarly to subtropical gyres, macronutrients were almost depleted in surface waters, while Ni never fell below 1.51 nmol kg-1, sug...

Journal of Geophysical Research: Oceans, 2017

The magnitude and temporal variability of mineral dust deposition and its associated Fe and Mn in... more The magnitude and temporal variability of mineral dust deposition and its associated Fe and Mn inputs to coastal waters of the California Current System (CCS) has been scarcely investigated. Here we report a 5 year time series (April 2010 to December 2014) of mineral dust (Fdust), Fe (FFe), and Mn (FMn) fluxes to the coastal zone of the southern CCS. Atmospheric deposition displayed a strong seasonal trend, with lowest Fdust, FFe, and FMn during the warm season (May–October), a period dominated by strong moisture‐laden winds of oceanic origin. In contrast, the highest Fdust, FFe, and FMn were recorded during the cool season (November–April), a period characterized by strong winds devoid of moisture coming from the mainland. Our analysis suggests that Santa Ana Wind events could contribute with ∼15%, 20%, and 24%, respectively, to the total annual input of dust, Fe and Mn to the region. Besides, atmospheric soluble Fe inputs are equivalent to between 11% (warm season) and 35% (cool s...

Geochimica et Cosmochimica Acta

Scientific Reports

Seabirds are known to play an important role in the geochemical cycling of macronutrients; howeve... more Seabirds are known to play an important role in the geochemical cycling of macronutrients; however, their role in cycling elements of environmental interest has not been investigated. Guano is an important source of marine-derived nutrients and trace metals in seabird nesting areas, but most of the available information on this topic is derived from local studies. In the present study, we used a bioenergetic model to estimate the amounts of cadmium (Cd), mercury (Hg) and lead (Pb) that are deposited via faecal material in seabird colonies worldwide. The findings showed that the seabirds excreted 39.3 Mg (Mg = metric ton or 1000 kg) of Cd, 35.7 Mg of Hg and 27.2 Mg of Pb annually. These amounts are of the same order of magnitude as those reported for other fluxes considered in the geochemical cycling of these elements (e.g. sea-salt spray, cement production, soil loss to oceans). Most of the deposition occurs in circumpolar zones in both hemispheres and, interestingly, high proportio...

Marine Pollution Bulletin

Maó (Minorca) is a narrow and semi-enclosed harbour impacted by historic urban and industrial met... more Maó (Minorca) is a narrow and semi-enclosed harbour impacted by historic urban and industrial metal pollution. We analyse and compare surficial and long-term sediment records along the Harbour to assess the sources and historical trends in pollution. Trace metal concentrations (Al, Ca, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sr and Zn) measured in sediments of Maó were of the same order of magnitude than those reported in other anthropogenically impacted areas of the Mediterranean Sea. Mercury was the only element that presented significantly higher concentrations in the harbour than other sites (up to 2 orders of magnitude higher). Although surficial concentrations of some metals (e.g. Hg, Pb, Cu and Zn) showed levels lower than those presented in the oldest sedimentary record, they showed concentrations above those recommended for acceptable sediment quality. Enrichment factors (EF) calculations support the anthropogenic origin of these metals in the Maó harbour; however, some variations ...

Estuarine, Coastal and Shelf Science, 2014

Even though several studies on the geochemical processes occurring in mangrove soils and sediment... more Even though several studies on the geochemical processes occurring in mangrove soils and sediments have been performed, information on the diversity of Archaea and their functional roles in these ecosystems, especially in subsurface environments, is scarce. In this study, we have analyzed the depth distribution of Archaea and their possible relationships with the geochemical transformations of Fe and Mn in a sediment core from a tropical mangrove creek, using 16S rRNA gene profiling and sequential extraction of different forms of Fe and Mn. A significant shift in the archaeal community structure was observed in the lower layers (90e100 cm), coinciding with a clear decrease in total organic carbon (TOC) content and an increase in the percentage of sand. The comparison of the archaeal communities showed a dominance of methanogenic Euryarchaeota in the upper layers (0e20 cm), whereas Crenarchaeota was the most abundant taxon in the lower layers. The dominance of methanogenic Euryarchaeota in the upper layer of the sediment suggests the occurrence of methanogenesis in anoxic microenvironments. The concentrations of Feoxyhydroxides in the profile were very low, and showed positive correlation with the concentrations of pyrite and degrees of Fe and Mn pyritization. Additionally, a partial decoupling of pyrite formation from organic matter concentration was observed, suggesting excessive Fe pyritization. This overpyritization of Fe can be explained either by the anoxic oxidation of methane by sulfate and/or by detrital pyrite tidal transportation from the surrounding mangrove soils. The higher pyritization levels observed in deeper layers of the creek sediment were also in agreement with its Pleistocenic origin.

Marine Pollution Bulletin, 2005

The soft tissue of Mytilus californianus has the capacity to decrease its Cd concentration in the... more The soft tissue of Mytilus californianus has the capacity to decrease its Cd concentration in the order of days. However, for medium-term (months) pollution surveys it is necessary to find alternative structures capable of integrating Cd concentrations during longer periods of time. The recently deposited nacreous layer of the shell of M. californianus is proposed as such a structure. Daily variability of Cd concentration in the soft tissue and in the recently deposited nacreous layer of a natural population of mussels was compared during a period of 26 days in organisms collected from an upwelling zone of British Columbia. Statistical analysis of the Cd concentrations indicated that the nacreous layer presented less significant differences between days than the associated soft tissue. Only one shell sample showed significant differences in Cd concentrations, probably related to environmental conditions and stress arising from mussel population density. Experimental results carried out in the laboratory confirmed that the recently deposited nacreous layer of M. californianus is a better medium-term indicator of Cd in seawater, especially at low concentration exposures of this element, those similar to the ones encountered in natural environments.

SEPM Journal of Sedimentary Research, 1992

... This precludes the use of relatively simple diagenetic models in interpretation of the data t... more ... This precludes the use of relatively simple diagenetic models in interpretation of the data to be presented. METHODS Sediment cores were collected either from the R/V Longhorn or associated smaller craft during three cruises in September, 1985, July, 1986 and May, 1988. ...

Bulletin of Environmental Contamination and Toxicology, 2006

Regional Studies in Marine Science

Bulletin of Environmental Contamination and Toxicology, 2021

This study analyzed 27 surface sediment samples from the Tamaulipas Continental shelf to determin... more This study analyzed 27 surface sediment samples from the Tamaulipas Continental shelf to determine the spatial–temporal distribution of V and Cd (spring–summer 2016; summer 2017). Average V concentrations (99 ± 18 mg g −1 ) were similar to that previously reported values for the area, while average Cd concentrations reflect uncontaminated sediments at surface level of the shelf. Inputs of V and Cd may be related to hydrocarbon and anthropogenic contributions from South and North of the Gulf of Mexico. The variability shown by both elements results from the hydrodynamics and hydrology of the area produced by local currents, eddies of the Loop Current, resuspension of fine sediments and contribution of terrigenous material. Considering that both metals showed significant differences (Shapiro–Wilk, p = 0 ), baseline concentrations could not be established, instead a reference interval of 79–122 µg g −1 for V and 0.121–0.258 µg g −1 for Cd in sediments from the Tamaulipas platform is suggested.

Journal of Water Process Engineering, 2021

Abstract This study aimed to investigate the adsorption performance of a macroalgae-based biocomp... more Abstract This study aimed to investigate the adsorption performance of a macroalgae-based biocomposite as a biosorbent of water-soluble hydrocarbons (WSH) like BTEXN (benzene, toluene, ethylbenzene, xylenes, and naphthalene) on packed bed columns. The effects of the inlet flow rate (0.3–1.1 mL/min), using naphthalene as a model, were analyzed and the operation parameters are described. The registered breakthrough volume increased from 12 to 52 mL at an EBCT of 4 and 20 min, respectively. The breakthrough curves profiles of the competitive biosorption of BTEXN were modeled by five well-accepted dynamic adsorption models known as Thomas, Clark, Dose-Response, BDST, and Yoon-Nelson. The biocomposite swelling degree and the external mass transfer limitations are the main factors influencing the adsorption process at different inlet fluxes, a result that was corroborated by the linearized Yoon-Nelson model. In the case of multicomponent systems, the hydrocarbon hydrophobicity determined the composite selectivity (N > X > E > T > B), with breakthrough volume values from 7.51 to 14.33 mL for natural water, and from 12.14 to 28.66 mL for deionized water. Finally, the evaluated biocomposite showed to be adequate for the continuous biosorption of water-soluble hydrocarbons.

Applied Geochemistry, 2020

Trace metal distribution and speciation studies in hypersaline systems are scarce because of the ... more Trace metal distribution and speciation studies in hypersaline systems are scarce because of the difficulty in measuring low metal concentrations in high salinity (S) waters. In this study, dissolved molybdenum (Mo D) was measured in samples collected in the hypersaline Ojo de Liebre Lagoon and evaporation ponds of the Guerrero Negro saltern, Baja California Peninsula, Mexico. Mo D was extracted from these hypersaline waters with a modification of a method originally developed to measure this element in natural waters (S < 36). In general, Mo D concentrations ranged from 42 to 241 nM along the hypersaline gradient, well below those predicted from simple seawater evaporation, indicating non-conservative behavior of Mo D relative to salinity. The magnitude of the removal process was reflected in both the high calculated Mo D fluxes toward the sediment/microbial mat (2.2 ton yr À 1), and the very short residence time of Mo D (4.1 yr) in the water column of the evaporation ponds. These findings suggest that sediments/microbial mats and also gypsum from current hypersaline environments act as important, but as yet unquantified, Mo D sinks. Removal of Mo D in hypersaline environments may have been especially important during the geological past, when these environments were more prevalent and extensive, and thus capable of influencing the global Mo cycle as well as, indirectly, the nitrogen cycle.

Science of The Total Environment, 2016

Dinoflagellate algal blooms have increased over time in coastal areas • Vertical and temporal var... more Dinoflagellate algal blooms have increased over time in coastal areas • Vertical and temporal variability of Cd p , Cd d , PO 4 3-, and Cd d /PO 4 3was investigated • High Cd d and Cd p seawater concentrations were associated with L. polyedrum abundance • A decoupling in the behavior of Cd and PO 4 3was associated with bloom development • An abundance threshold of~10 6 cells L-1