Matanza River Research Articles

Developmental reaction norms vary among families of lizards in response to multivariate nest environments

Developmental plasticity is the capacity of a single genotype to express multiple phenotypes in response to different early‐life environments. Such responses are defined by reaction norms, which may vary among individuals or populations. Variation in developmental reaction norms allows natural selection to operate on plasticity and is rarely examined in vertebrates. We quantified variation in embryonic developmental plasticity within and between populations using the brown anole lizard. We captured lizards from two islands in the Matanzas River (Florida, USA) and incubated their eggs under one of two multivariate treatments that mimicked the temperature, moisture and substrates of nest sites in either a shaded or open habitat. We measured hatchling morphology, performance, and physiology to quantify variation in family‐level reaction norms. We observed evidence of family‐level variation in reaction norms for morphology but not for performance or physiology, indicating an opportunity for natural selection to shape plasticity in hatchling body size. Overall, the results indicate that multiple abiotic conditions in natural nests combine to increase or reduce phenotypic variation, and that family‐level variation in reaction norms provides a potential for natural selection to shape plasticity.

"We've Got to Be Awful Careful or We're Going to Lose It": Documenting Life Along Florida's Matanzas River

"We've Got to Be Awful Careful or We're Going to Lose It": Documenting Life Along Florida's Matanzas River

Ultrastructural Alterations in Lepocinclis acus (Euglenophyta) Induced by Medium with High Organic Matter Content

Ultrastructural changes induced by exposure to excess of organic matter were studied in Lepocinclis acus (ex Euglena acus). The cells isolated from the Matanza River, Buenos Aires, Argentina, were grown in soil water medium. When transferred to medium enriched with Bacteriological Peptone OXOID®, marked body deformation and a significant shortening and widening of the cells was observed. These changes were unexpected in a species with quite rigid cells, a condition previously shown in studies of the pellicle fine structure. Transmission electron microscopy observations suggest that cellular deformation might be facilitated by an increase in strip number, whereas in the original strips normal ultrastructure was maintained. An increase in number and volume of paramylon grains and vacuoles, as well as the presence of membrane whorls in vacuoles was observed. The fine structure of organisms grown in medium with and without organic matter enrichment was compared, and the systematic and ecological importance of morphological changes triggered by cell deformation was discussed.

Arsenic in the health of ecosystems: spatial distribution in water, sediment and aquatic biota of Pampean streams.

A survey of arsenic and phosphorus in Pampean streams of Buenos Aires province was performed. Nitrates and ammonia were also determined. Stream water was sampled as well as stream sediment and filamentous algae. Results show that 32 streams exceeded the arsenic recommended guidelines for human consumption of 10μgL-1 and six exceeded recommended values for aquatic organisms' protection of 50μgL-1. The average concentration found was 36.54μgL-1 and areas with more concentration of As are located in the southern region of the province, in streams that are tributaries of the Atlantic Ocean. Other regions with high As concentration are the Matanza River tributaries and the Arrecifes River tributaries. No differences of As concentration was found between stream sediments. Also, no seasonal pattern of As concentration was observed in one stream sampled during a year, but a positive correlation between As and the conductivity (p=0.0002) and pH (p=0.01) of the streams was found. Also, As bioaccumulation was detected for all the algae sampled, but no correlation between As accumulated and As in the stream water was found. Ammonia levels exceeded recommended guidelines for human consumption in the Argentinean law in 30 streams. The characterization performed in this study provides relevant information on the distribution of arsenic and its origin and mobility.

Life on the leading edge: Phenology and demography of the red mangrove Rhizophora mangle L. at the northern limit of its expanding range

Mangroves are expanding northward along the eastern coast of Florida and invading saltmarsh communities along the tributaries and main channels of rivers that flow into the Intracoastal Waterway system. To investigate R. mangle’s demography, reproductive effort and survivorship of offspring were monitored for three years along the Matanzas River, northern Florida. Flowering was delayed, fruit production was year-round and hypocotyl production covered a longer period than for populations further south. If a propagule survived to the recruit stage, the individual was more likely to produce branches. In addition, if the propagule recruited in mud and in the low intertidal zone, then the individual was more likely to survive to the juvenile stage. Those propagules that eventually developed into juveniles had remained within one meter of the parent, had recruited in a vertical position and had larger hypocotyls. Two adults contributed 79% of the propagules that survived to the branched stage. These successful adults become the islands from which the population persists and expands along the leading edge of its distribution.

Seminavis norae comb. nov. is the correct name for Seminavis recta

Cymbella (Encyonema) grossestriata var. recta Frenguelli (1938: 303) was described by Joaquín Frenguelli (1883–1958) from the Matanza river estuary in Buenos Aires, Argentina. It was subsequently transferred to the genus Navicula Bory (1822b: 128) by Metzeltin et al. (2005: 138), who elevated Frenguelli’s variety to species level. The authors provided evidence that the taxon was not related to Cymbella grossestriata O. Müller (1905: 154) and did not belong to either Cymbella C.A. Agardh (1830: 1) or Encyonema Kützing (1833: 589).

Spatial conservation prioritization to conserve biodiversity in response to sea level rise and land use change in the Matanzas River Basin, Northeast Florida

Sea level rise and land use change are likely to be some of the most fundamental and important challenges for biodiversity conservation in low-lying coastal areas in the 21st century. To protect biodiversity in coastal areas, there is an urgent need to identify conservation priorities in response to sea level rise and land use change. In this study, an integrated modeling process using a geomorphological model, species habitat models, and conservation prioritization is developed to identify conservation priorities in the face of sea level rise and land use change. We present a case study in the Matanzas River Basin of Northeast Florida that utilizes this integrated modeling approach with data for 38 focal species. We incorporate species-specific connectivity requirements in the analysis and compare the conservation priorities with existing conservation datasets including current conservation areas and the Florida Ecological Greenways Network (FEGN). Results show that current reserves are not adequate to protect some of the most important conservation priorities in response to sea level rise but the updated FEGN does serve as a good foundation to inform future conservation decisions relevant to sea level rise. To protect the top 10% conservation priorities, approximately 11,700, 10,900 and 15,200 acres of additional land will need to be acquired for the 0.5, 1.0, and 2.5m sea level rise scenarios respectively.

Integrating conservation costs into sea level rise adaptive conservation prioritization

Biodiversity conservation requires strategic investment as resources for conservation are often limited. As sea level rises, it is important and necessary to consider both sea level rise and costs in conservation decision making. In this study, we consider costs of conservation in an integrated modeling process that incorporates a geomorphological model (SLAMM), species habitat models, and conservation prioritization (Zonation) to identify conservation priorities in the face of landscape dynamics due to sea level rise in the Matanzas River basin of northeast Florida. Compared to conservation priorities that do not consider land costs in the analysis process, conservation priorities that consider costs in the planning process change significantly. The comparison demonstrates that some areas with high conservation values might be identified as lower priorities when integrating economic costs in the planning process and some areas with low conservation values might be identified as high priorities when considering costs in the planning process. This research could help coastal resources managers make informed decisions about where and how to allocate conservation resources more wisely to facilitate biodiversity adaptation to sea level rise.

Sea-Level Rise, Inundation, and Marsh Migration: Simulating Impacts on Developed Lands and Environmental Systems

ABSTRACT Linhoss, A.C.; Kiker, G.; Shirley M., and Frank K., 2015. Sea-level rise, inundation, and marsh migration: simulating impacts on developed lands and environmental systems. Sea-level rise is expected to affect natural and urban areas by shifting habitats and inundating infrastructure. To plan for a sustainable future, it is important to identify both human and ecological vulnerabilities to sea-level rise. Here, we simulate impacts to urban, developed lands and environmental systems from sea-level rise by analyzing land cover (surface cover) and land use (land purpose) in the Matanzas River study area in NE Florida. The Sea Level Affecting Marshes Model (SLAMM) simulated land-cover change through wetland migration under three sea-level rise scenarios. Parcel data, including land use classification and land valuation, was overlaid on the simulated, future land cover. Our analysis describes a 2- to 5-km-wide longitudinal band along the NE coast of Florida of expected land-cover change where sea-level...

Ultrastructural alterations in Phacus brachykentron (Euglenophyta) due to excess of organic matter in the culture medium

Morphological and ultrastructural changes induced by exposure to excess of organic matter were analyzed in Phacus brachykentron (Pochm.). The cells were isolated from sites in Matanza River, Buenos Aires, Argentina, which have a high degree of organic matter contamination coming from waste waters discharges of the meat industry. Master strains were cultured on soil water medium and a toxicity bioassay was performed. As a result of the enriched medium, several morphological and ultrastructural cellular alterations were observed by optical, scanning, and transmission electron microscopy. Among these, we can point out changes in cell dimensions, remarkable widening of some pellicle bands, increased number and volume of paramylon grains, displacement of the nucleus from the central to the lateral position, some chloroplasts with their thylakoids disordered, and cell lysis. The response to organic enrichment was very fast, i.e. during the 48h of the bioassay. Therefore, any significant increase of organic matter would rapidly affect wild euglenoids. Our results suggest that the alterations observed, such as the presence of large intracellular paramylon bodies or the deformation of euglenoid cells in natural samples, have the potential to be used as environmental bioindicators.

Fall and winter estuarine recruitment of bluefish Pomatomus saltatrix: selectivity for large lipid-rich prey increases depleted energy levels

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 492:235-252 (2013) - DOI: https://doi.org/10.3354/meps10471 Fall and winter estuarine recruitment of bluefish Pomatomus saltatrix: selectivity for large lipid-rich prey increases depleted energy levels Francis Juanes1,2,*, Peter J. Clarke1, John Murt1 1Department of Environmental Conservation, University of Massachusetts, Amherst, Massachusetts 01002, USA 2Present address: Department of Biology, University of Victoria, Victoria, British Columbia V8W 3N5, Canada *Email: juanes@uvic.ca ABSTRACT: The early life history of bluefish Pomatomus saltatrix follows a complex cycle with several migrations to and from estuarine nurseries. In contrast to spring and summer, little is known about fall and winter estuarine habitat use of juvenile bluefish. Here, we examined fall and winter estuarine ecology of juvenile bluefish in the Matanzas River Estuary in northeastern Florida over a 2 year period. Three distinct intra-annual cohorts of young-of-the-year (YOY), and age 1+ fish were identified through size frequencies and verified with otoliths. Estuarine recruitment was first observed in late October by spring-spawned and age 1+ fish, followed by summer-spawned YOY, and finally by the fall-spawned cohort with no new recruitment after February. Interannual differences in the timing of estuarine entry were likely due to variation in shelf cooling. A peak in relative abundance was observed in December. The highest relative abundances were found near the sandy inlets. Fish dominated the diet of all bluefish cohorts, mugilids by age 1+ and spring-spawned YOY bluefish, and engraulids by summer- and fall-spawned YOY. In contrast to previous studies, YOY and age 1+ bluefish were strongly selective for Mugil spp. prey. Bluefish lipid content increased over the fall and winter, peaking in January. A comparison of prey lipid levels across 30 potential prey species showed that Mugil spp. had the highest lipid content, 5 to 6× higher than lipid levels in other common prey items. We conclude that juvenile bluefish use Florida estuaries during the fall and winter to increase depleted lipids through selective feeding. Year class strength and cohort survival may be strongly related to the availability of selected prey items during this time. KEY WORDS: Juvenile recruitment · Winter ecology · Lipid dynamics · Predator–prey Full text in pdf format PreviousNextCite this article as: Juanes F, Clarke PJ, Murt J (2013) Fall and winter estuarine recruitment of bluefish Pomatomus saltatrix: selectivity for large lipid-rich prey increases depleted energy levels. Mar Ecol Prog Ser 492:235-252. https://doi.org/10.3354/meps10471 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 492. Online publication date: October 31, 2013 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2013 Inter-Research.

Factors Controlling Phytoplankton Biomass in a Subtropical Coastal Lagoon: Relative Scales of Influence

Patterns in phytoplankton biomass are essential to understanding estuarine ecosystem structure and function and are the net result of various gain and loss processes. In this study, patterns in phytoplankton biomass were explored in relation to a suite of potentially regulating factors in a well-flushed, subtropical lagoon, the Matanzas River Estuary (MRE) in northeast Florida. We examined temporal variability in water temperature, light availability, nutrient concentrations, phytoplankton productivity, and phytoplankton standing stock over 8 years (2003–2010) and explored relationships among variables through correlation analysis. Laboratory experiments in the spring and summer of 2009 quantified phytoplankton growth rates, nutrient limitation potential, and zooplankton grazing rates. The potential influence of oyster grazing was also examined by scaling up population metrics and filtration rate estimates. Results indicated that phytoplankton biomass in the study area was relatively low mainly due to a combination of low temperature and light availability in the winter and consistent tidal water exchange and bivalve grazing throughout the year. Relatively low levels of phytoplankton standing stock and small inter-annual variability within the MRE reflect a balance between gain and loss processes which provide a degree of resilience of the system to natural and anthropogenic influences.

Application of the biotic ligand model for regulatory purposes to selected rivers in Argentina with extreme water‐quality characteristics

The biotic ligand model (BLM) was used to assess copper (Cu) bioavailability, toxicity, water-effect ratios (WER), and Cu site-specific water-quality criteria (SSWQC) in the Matanza River and Pilcomayo River, Argentina, where anthropogenic inputs and natural phenomena have led to high concentrations of chemical species capable of reducing metal toxicity: Sodium, total hardness, alkalinity, dissolved organic carbon, and suspended particulate matter (SPM), as well as other metals. The purpose of this study was to evaluate the feasibility of developing Cu-SSWQC from a modified scenario of the BLM-Monte-Carlo method model. The response of the BLM model in these rivers, with water quality near its application boundary conditions, was evaluated during the 2003 to 2004 hydrological cycle. Cu toxicity tests were conducted with Daphnia magna as the test organism. The BLM (Version ap08) toxicity estimates for D. magna were within a factor of 2 of the line of perfect agreement with toxicity test results, although highly variable relevant water-quality parameters showed that mean estimates were more than 2 times the mean 50% effective concentration (EC50) derived from the corresponding toxicity tests. Suspended particulate matter was an important sink for Cu added to unfiltered water of the Pilcomayo River, but it also exerted some toxic effect. Minimums WER, estimated with a modified scenario of the BLM-MONTE, ranged from 1.5 (Pilcomayo River, at Misión La Paz) up to 11 (Matanza River, at Route 3). The corresponding Cu-SSWQC values were 30 and 105 microg/L, respectively.

Ultrastructure and X-ray microanalysis of Euglena gracilis (Euglenophyta) under chromium stress

I. Rocchetta, P.I. Leonardi, G.M. Amado Filho, M. del Carmen Ríos de Molina and V. Conforti. 2007. Ultrastructure and X-ray microanalysis of Euglena gracilis (Euglenophyta) under chromium stress. Phycologia 46: 300–306. DOI: 10.2216/06-49.1The effect of chromium on the biology of Euglena gracilis was studied. The ultrastructural modifications caused by this metal and its location within the cell were analyzed by TEM and EDXA, respectively. The effects of chromium on protein, pigment, and lipid contents were also studied in order to evaluate the metabolic responses to metal exposure. Two strains of Euglena gracilis, UTEX 753 (from the Culture Collection of Texas University) and MAT (isolated from the Matanza River), were used in this research. Both were grown in photoauxotrophic and photoheterotrophic conditions and exposed to different metal concentrations. In all treated cells, increases in total protein and lipid contents, changes in chlorophyll amount, and alterations in fine structure were observed, especially with the higher concentration tested. In photosynthetic treated cells, assays showed chloroplast thylakoid disorganization, the presence of cytoplasm lipid globules, and several vacuoles with electron-dense inclusions and remnants of membranes inside. Nuclei presented lobulations, and eventually total fragmentation in some cells treated with the highest chromium concentration was seen, suggesting that chromium cytotoxicity leads to cellular death. The EDXA spectrum showed well-defined Cr and S peaks in the vacuoles containing electron-dense inclusions and remnants of membranes from autotrophic MAT samples. These results indicate that the different defense mechanisms against chromium depend on strain type and culture conditions. The S peak detected in MAT would suggest that sulfur-rich proteins groups play an important role in the detoxification system inducing metal-complex accumulation into vacuoles.

Heavy Metals in Sediments and Runoff Waters in Soils of the Matanza River Basin, Argentina

Soil profiles near watercourses that drain rural areas with agricultural lands and pastures, as well as recreational zones and densely populated industrial centers, are directly influenced by human activities. Therefore, these soils condition the contamination dynamics of the aforementioned watercourses in a remarkable way. The present study deals with soils belonging to a first order subbasin. Pedons representative of positive areas located in slopes (B) and of alkaline sites close to the alluvial plane (T) were selected as study sites. In both cases, the land is used for extensive farming. Composite samples of the upper 5 cm of both soil types were treated either with vermicompost or phosphate fertilizer to study the effect of the addition of these elements on the runoff dynamics of heavy metals. Experiments using a rainfall simulator that formed drops on runoff microplots containing soil samples were carried out under laboratory conditions. The runoff obtained was analyzed for lead (Pb), zinc (Zn), cadmium (Cd), and nickel (Ni), both dissolved and particulate, following the Community Bureau of Reference (BCR) adaptation of the sequential extraction procedure. From these results, it was concluded that the use of high amounts of organic amendment produced important effects on the surface condition of the soils that determine a highly significant reduction in the delivery of suspended solids to watercourses. Amendments, however, may release heavy metals that flow through runoff avenues either as particulate or dissolved forms. Most of the heavy metal concentration is represented by the sediments produced by the runoff and not by the concentration of dissolved elements in runoff waters.

Molecular approach to microbial diversity studies in the heavily polluted Matanza River

The moss flora of the Fuegian region is fairly well-known and the unexplored areas are relatively few. The compilation of all the records scattered over more than two centuries of exploration and studies in Tierra del Fuego and the Malvinas Islands resulted in the recognition of 369 species, 3 subspecies and 29 varieties distributed in 119 genera. A few taxa newly recorded for the region are: Fallaciella Crum, Campylopus subnitens Kaal., Dicranoweisia mackayi (Broth. & Dix.) Broth., Didymodon andreaeoides Card. & Broth., Fallaciella gracilis Crum, and Philonotis polymorpha (Müll. Hal ) Kindb. Acroschisma wilsonii (Hook. f.) A. Jaeger is a new species for the Argentine territory

Formas geoquímicas de metales pesados en sedimentos del Río Matanza y principales afluentes

Geochemical forms of heavy metals in sediments from the Matanza River and its main affluents. Sequential fractionation was applied to partition heavy metals in river sediments taken from the Matanza-Riachuelo basin. Although there was observed a considerable variation among the heavy metals in the proportion of various fractions, Pb showed a similar distribution pattern between the four sampling sites. The organic matter/sulfides fractions of this metal strongly dominated over the other fractions. The speciation of Cu showed a relative high percentage of carbonates and organic mater/sulfides fractions. Zinc showed a high proportion of Fe-Mn oxides. Cadmium was only detected in Cañuelas stream sediments and existed in the exchangeable and carbonates fraction showing a high potential mobility of this element.

Aeromonas salmonicida subsp. pectinolytica subsp. nov., a new pectinase-positive subspecies isolated from a heavily polluted river.

Aeromonas strains which phenotypically and genetically belong to the Aeromonas salmonicida species but that according to their phenotypic properties constitute a new subspecies have been isolated from the water of a heavily polluted river, the Matanza river, situated near the central district of Buenos Aires city. These strains were ascribed to the A. salmonicida species by using 65 biochemical tests and by DNA-DNA hybridization. They produce acid from -sorbitol, an unusual biochemical property found in a few members of the A. salmonicida species. They also utilize urocanic acid and do not ferment L-rhamnose or utilize LD-lactate, and are elastase- and gluconate-negative. The DNA relatedness was over 70%, the current limit accepted for the phylogenetic definition of a species, to the described A. salmonicida subspecies and nearly 100% within the new group of Aeromonas strains. Phenotypic differentiation from other A. salmonicida subspecies was readily achieved using the following characteristics: growth at 37 degrees C, melanin production, indole and Voges-Proskauer assays, growth on KCN broth, mannitol and sucrose fermentation and gas from glucose. A remarkable property of the strains of the new group was their ability to degrade polypectate, an unusual feature among Aeromonas species in general. The complete 16S rRNA gene of one strain of the new group was sequenced. Comparison with rDNA sequences of Aeromonas members available in databases revealed a close relationship between this strain and strains belonging to A. salmonicida subsp. salmonicida, masoucida and achromogenes, in agreement with the biochemical data. Since the new A. salmonicida strains constitute a tight genomic group that can be identified by phenotypic properties it was concluded that they represent a new subspecies for which the name Aeromonas salmonicida subsp. pectinolytica is proposed. The type strain of A. salmonicida subsp. pectinolytica is 34melT (= DSM 12609T).

Kluyvera bacteriophage Kvp1: a new member of the Podoviridae family phylogenetically related to the coliphage T7

A DNA containing bacteriophage, Kvpl, was isolated from the water of a very polluted river, the Matanza river, near the central district of Buenos Aires City. This bacteriophage infects bacteria belonging to the Kluyvera cryocrescens species (strain 21g) isolated from the same river. Kvpl is a lytic bacteriophage and its propagation characteristics are: burst size 30, latent period 13 min and rise period 10 min. Morphologically, kvpl is a small icosahedral bacteriophage, 59.1 nm in diameter, which possesses a short wedge-shaped tail. Its buoyant density in ClCs is 1.517 g/cm 3. Kvpl DNA is linear, double stranded and approximately 40 000 bp in size. The viral particle is composed of at least nine proteins. SDS-PAGE patterns of these proteins and of those produced during the host infection, in addition to its morphological and genomic characteristics, suggested that Kvpl is similar to the relationship to the coliphage. Taking this into account, the partial sequence of the phage RNA polymerase was used to construct phylogentic relationships between Kvpl and other related phages. To our knowledge, Kvpl is the first bacteriophage described which uses as host a member of the Kluyvera bacterial genus.

DISCUSSION OF “Hydrodynamic Behavior of the Puelche Aquifer in Matanza River Basin,” by Miguel P. Auge, September‐October 1986 issue, v. 24, no. 5, pp. 636–642

DISCUSSION OF “Hydrodynamic Behavior of the Puelche Aquifer in Matanza River Basin,” by Miguel P. Auge, September‐October 1986 issue, v. 24, no. 5, pp. 636–642