Papers by Alejandro Cabello-Pasini
Ciencias Marinas
The effects of temperature, irradiance, and other environmental variables on photosynthesis in se... more The effects of temperature, irradiance, and other environmental variables on photosynthesis in seagrasses are well understood. However, little information is available regarding the effects of the nitrate concentration in seawater on the photosynthetic characteristics of marine vegetation. Thus, the aim of this study was to determine the effect of the nitrate concentration in seawater on the effective quantum yield of the seagrass Cymodocea nodosa. Cymodocea nodosa shoots were incubated under different irradiance levels and with different nitrate concentrations. In contrast, a decrease in transmittance and an exponential increase in the absorptance of the shoots were observed as a function of increasing nitrate levels. Furthermore, the effective quantum yield of photosystem II (ΦPSII) in C. nodosa shoots increased exponentially as the nitrate concentration in the media increased. The ΦPSII values in the shoots decreased as irradiance increased and reached minimum values at solar noo...
Ciencias Marinas
Coralline algae form abundant and ecologically important submerged aquatic vegetation habitats th... more Coralline algae form abundant and ecologically important submerged aquatic vegetation habitats throughout the world. However, algal performance is threatened by climate change and ocean acidification. Previous studies suggest that their photosynthetic performance will be compromised mainly at elevated temperatures. Understanding the impact of diverse climate change scenarios requires a clear and thorough comprehension of the photosynthetic response to temperature gradients. The objective of this study was to evaluate the short-term effect of temperature (10–35 °C) on the gross photosynthesis (GPS), respiration, and electron transport rates (ETRs) of 3 articulated coralline algae (Lithothrix aspergillum, Corallina officinalis, and Bossiella orbigniana) for a better understanding of their metabolism and to investigate the relationship between GPS and ETR as a function of temperature. The results showed that the coralline algal metabolism is highly sensitive to temperature, but respons...
Intra-thallus variation of phenolic compounds, antioxidant activity, and phenolsulphatase activity in Cystoseira tamariscifolia (Phaeophyceae) from southern Spain Variación intratalo de compuestos fenólicos, actividad antioxidante y actividad de la fenolsulfatasa en Cystoseira tamariscifolia (Pha...
Combined effects of marine heatwaves and reduced light on the physiology and growth of the surfgrass Phyllospadix torreyi from Baja California, Mexico
Aquatic Botany, 2022
Ecophysiological responses and self-protective canopy effects of surfgrass (Phyllospadix torreyi) in the intertidal
Marine Environmental Research, 2021
Intertidal seagrasses are subjected to desiccation and direct solar radiation during low tides. I... more Intertidal seagrasses are subjected to desiccation and direct solar radiation during low tides. It is assumed that the canopy structure can self-protect the underlying shoots during these events, although there is no evidence on a physiological basis. The physiological responses of the surfgrass Phyllospadix torreyi were examined when emerged during low tide, on i) shoots overlaying the canopy, and ii) shoots sheltered within the canopy. Leaf water potential and water content decreased in external leaves after emersion, and the higher concentration of organic osmolytes reflected osmoregulation. Additionally, these shoots also exhibited a drastic reduction in carbohydrates after re-immersion, likely from cellular damage. Lipid peroxidation and antioxidant activity increments were also detected, while photosynthetic efficiency strongly diminished from direct exposure to solar radiation. Conversely, the sheltered shoots did not dehydrate and solely accumulated some oxidative stress, likely resulting from the warming of the canopy. In conclusion, the leaf canopy structure buffers physiological stress in the sheltered shoots, thus acting as a self-protective mechanism to cope with emersion.
South African Journal of Enology and Viticulture, 2020
Phenolic compounds are secondary metabolites synthesised in response to biotic or abiotic stress ... more Phenolic compounds are secondary metabolites synthesised in response to biotic or abiotic stress in plants. This stress-induced increase in phenolic compound concentrations is generally activated by internal levels of abscisic acid (ABA). The exogenous application of ABA or calcium chloride on grapevines is also known to increase grape yield and alter the phenolic composition of grapes. Residues of cement industries such as calcium carbonates (CaCO 3 ) are a safe environmental source of calcium that could be used to induce the synthesis of phenolic compounds and act as a yield promoter in grapes and other crops. Consequently, the objective of this study was to evaluate the effect of cement industries' CaCO 3 residues (CaCO 3 R) on the yield and concentration of phenolic compounds in Shiraz grapes. Thirteen phenolic compounds were identified and quantified by HPLC-DAD. Malvidin-3-O-glucoside was the major anthocyanin found in Shiraz grapes, and its concentration increased by more than 200% in CaCO 3 R-treated vines. Similarly, the concentration of cinnamic acid, the main precursor of phenolic compounds, increased by more than 900% in grapes treated with CaCO 3 residues at harvest time. Finally, catechin, epicatechin and procyanidin B1 and B2 increased significantly at harvest time in CaCO 3 R-treated grapes relative to the controls. In general, it was found that foliar application of CaCO 3 residues from the cement industry at véraison induced an increase in yield, and in the concentration and composition of phenolic compounds in grapes.
Regulation of Nitrate Uptake by the Seagrass Zostera marina During Upwelling
Estuaries and Coasts, 2019
Prolonged nitrogen (N) fertilization can impact seagrass survival and productivity; however, the ... more Prolonged nitrogen (N) fertilization can impact seagrass survival and productivity; however, the effects of N enrichment pulses (e.g., upwelling or sediment resuspension) remain poorly understood. This study examined the effects of short-term (1 h) pulsing of nitrate (NO3−) enrichment, simulating an upwelling event, on dissolved inorganic carbon (DIC) and NO3− uptake capacities, critical in controlling eelgrass productivity. Zostera marina dominates submerged vegetation in coastal lagoons influenced by upwelling in the California Current system. Laboratory incubations were conducted in winter (non-upwelling) and spring (upwelling) with shoots collected from San Quintín Bay meadows, Baja California, Mexico, differentially exposed to upwelled NO3−. Results suggest that NO3− enrichment stimulated DIC and NO3− uptake in winter, reflecting the close relationship between carbon metabolism and NO3− assimilation. Eelgrass shoots showed reduced NO3− incorporation in spring; neither NO3− uptake nor photosynthesis increased when exposed to high NO3−. Saturation of spring shoots at lower ambient NO3− concentrations may be interpreted as a physiological strategy to restrict metabolically costly NO3− incorporation during upwelling; this regulation of NO3− uptake strongly contrasts to the apparently full exploitation of this nutrient by seaweeds also dominant within the bay, as indicated in previous works. Despite their reduced NO3− uptake, eelgrass meadows near the bay mouth acquire NO3− at rates up to 4.2 mmol N m−2 day−1. This represents non-trivial water column NO3− removal compared to the estimated oceanic NO3− supply (~ 7.1 mmol m−2 day−1) during upwelling, highlighting the importance of Z. marina beds in controlling the lagoonal N-budget.
Short-term response and recovery of Zostera capricorni photosynthesis after herbicide exposure CMO Macinnis-Ng and PJ Ralph (Gore Hill, Australia)...................... 1 A combined approach of photogrammetrical methods and field studies to determine nutrient retention by submersed macrophytes in...
Preface: San Quintin in 2002
Chlorella Fusca Growth in Swine Wastewater Effluent for the Production of Biofuels
JL Reguzzoni, S. Wyllie-Echeverria, M. Josselyn and RS Alberte. 1991. Assessment of environment suitability for growth of Zostera marina L.(eelgrass) in San Franscisco Bay
Conservation status of Zostera marina populations at Mexican Pacific
ABSTRACT Human activities and global warming are driving major modifications in the world’s ecosy... more ABSTRACT Human activities and global warming are driving major modifications in the world’s ecosystems; the coastal zone being one of the most damaged because less attention. Seagrass meadows constitute coastal communities that have experienced great losses worldwide but remains as one of the most productive. The dominant seagrass in the meadows of the coastal lagoons at Mexican Pacific coast is Zostera marina L. and represent the southern boundary of the species in the northeast Pacific. This species is heavily damaged by human activities mainly fisheries trawling and the lack of an appropriate legal protection and no management plan available. Even when seagrasses are considered as part of the Mexican Official Norm (NOM-022-SEMARNAT-2003) who protects mainly mangrove and wetlands in general and brief mention of seagrasses is made. They are not considered in the species endanger list (NOM-ECOL-059). Pacific coast populations of Z. marina are not only separated geographically but also genetically from populations in the Gulf of California. They are also exposed to different current regimes and environmental conditions. As part of a long term studies of demographic, ecophysiological and phylogeographic studies of Z. marina we are presenting here a review of the conservational status of the populations along the Mexican Pacific over the last 2 decades. Population studies have shown that Z. marina has a mixture of perennial and annual populations around the area but most of historically known sites have started to decline or completely disappear. At least 50% of the historically known sites are not longer present and the other 40% have strong impacts with reduction of their area and density causing severe pressure in the trophic structure. Severe cases, as San Ignacio Lagoon in the Pacific Coast of Baja California and the case of coastal lagoons of the eastern Gulf of California are presented as case study. Zostera marina also displays significant interpopulation differences in morphology, biochemical composition and depth distribution along this coastline that appear to be promoted by variation in climatic conditions. Furthermore, Z. marina displays restricted pollen and seed dispersal, even in areas with strong tidal currents (50 cm s-1). Analyses of molecular variance revealed significant interregional differentiation, but no subregional differentiation. Significant spatial differentiation, assessed using ST values, was observed among all populations. The test for isolation by distance showed a significant correlation between genetic and geographical distances in Gulf of California populations, but not in Pacific coast populations, perhaps because of shifts in currents during El Niño Southern Oscillation events along the Pacific coast. Because of that we strongly suggest that special areas for conservation of Z. marina should be declared along the Mexican Pacific with the development of a management plan based on a scientific agenda.
The effect of reclaimed wastewater on the quality and growth of grapevines
Water Science and Technology, 2008
The effect of the use of treated wastewater on the growth of cabernet sauvignon and merlot grapes... more The effect of the use of treated wastewater on the growth of cabernet sauvignon and merlot grapes from the Guadalupe Valley, Mexico was evaluated. Secondary advanced effluent was used to irrigate the grapevines at a rate of 66 L/vine/week. Wastewater quality results confirmed that all parameters complied with Mexican legislation for crop irrigation as well as reuse in activities in which the public would be in direct or indirect contact with the reclaimed water. Results showed that the number of leaves per shoot and the overall biomass increased in plants irrigated with wastewater and grape production per plant was 20% higher. The concentration of carbohydrates, organic acids and pH were similar in grapes from vines irrigated with wastewater to those irrigated with groundwater. Throughout the experiment, no fecal coliform bacteria were detected in the cultivated grapes. The wastewater caused an increase in the biomass of the grapevines and there was no presence of microbial indicato...
Revista chilena de historia natural, 2001
Seasonal Patterns of Photosynthesis and Light‐Independent Carbon Fixation in Marine MACROPHYTES1
Journal of Phycology, 1997
ABSTRACTThe contribution of light‐independent carbon fixation (LICF) to the overall carbon gain a... more ABSTRACTThe contribution of light‐independent carbon fixation (LICF) to the overall carbon gain and the seasonal patterns of maximum photosynthesis (Pmax and LICF were characterized in a broad taxonomic range of macrophytes from Monterey Bay, California. Pmax and LICF rates (nmol C.g filtered seawater−1.min−1) varied among species and taxonomic groups examined, and as a function of tissue type in the phaeophyte Laminaria setchellii Silva (Phaeophyceae). On average, Pmax values were higher in the Rhodophyta, whereas LICF rates were greater in the Phaeophyceae. LICF rates were generally less than 5% of Pmax in the marine macrophytes studied and, as a consequence, cannot fully compensate for respiratory carbon losses, which usually are greater than 10% of Pmax. All species studied possessed the highest Pmax and LICF rates when irradiance levels were highest and decreased during periods of low incident irradiance. Seasonal patterns of Pmax and LICF in most of the macrophytes from the st...
Phosphoenolpyruvate Carboxykinase from the Marine Diatom Skeletonema costatum and the Phaeophyte Laminaria setchellii. I. Isolation and Biochemical Characterization
Botanica Marina, 2000
Abstract Phosphoenolpyruvate carboxykinase (PEPCK) accounts for the bulk of non-photosynthetic ca... more Abstract Phosphoenolpyruvate carboxykinase (PEPCK) accounts for the bulk of non-photosynthetic carboxylation processes in the marine diatom Skeletonema costatum and the kelp Laminaria setchellii. Activity of the carboxylating enzyme phosphoenolpyruvate carboxylase was undetected in both the diatom and the kelp. The 53-fold purification of diatom PEPCK through gel-filtration and ion-exchange chromatography yielded a 13% recovery of the overall activity. Denaturing gel electrophoresis of diatom PEPCK revealed ...
Phosphoenolypyruvate Carboxykinase from the Marine Diatom Skeletonema costatum and the Phaeophyte Laminaria setchellii. II. Immunological Characterization and Subcellular Localization
Botanica Marina, 2001
Abstract Phosphoenolpyruvate carboxykinase (PEPCK) is responsible for light-independent carbon fi... more Abstract Phosphoenolpyruvate carboxykinase (PEPCK) is responsible for light-independent carbon fixation (LICF) processes in a wide range of marine algae, however, little is known about the intracellular localization of the enzyme among different algal groups. Antibodies against PEPCK recognized polypeptides in electrophoresed samples of cell-free extracts from only non-green phytoplankton and macrophytic Phaeophyta while antibodies against phosphoenolpyruvate carboxylase (PEPC) recognized polypeptides in samples of only ...
Propagule release and recruitment in Porphyra perforata (Rhodophyta) from Baja California, Mexico
Botanica Marina, 2005
Abstract This study determined the effect of irradiance, temperature and photoperiod on the relea... more Abstract This study determined the effect of irradiance, temperature and photoperiod on the release of zygotospores and spermatia in Porphyra perforata from the Pacific coast of Baja California, Mexico. Reproductive blades were placed under controlled conditions of irradiance (5, 75, 150 and 300 μmol photons m− 2 s− 1), photoperiod [8: 16; 12: 12 and 16: 8 light: dark (L: D)] and temperature (15, 18, 21 and 25 C). Peak zygotospore release occurred at 15–18 C and photoperiod of 16: 8 L: D. Reproductive tissue released between 60% and ...
Effect of storms on photosynthesis, carbohydrate content and survival of eelgrass populations from a coastal lagoon and the adjacent open ocean
Aquatic Botany, 2002
Annual variations in density, morphology, pigment levels, carbohydrate levels and photosynthetic ... more Annual variations in density, morphology, pigment levels, carbohydrate levels and photosynthetic characteristics of Zostera marina L.(eelgrass) from a coastal lagoon and from an unprotected area in the open coast were compared to understand the environmental regulation of this species growing near the southern limit of its distribution in the eastern Pacific. From January to April of 1997, light attenuation coefficients at the lagoon and the open coast increased six-fold as a result of sediment resuspension caused by storms in ...
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Papers by Alejandro Cabello-Pasini