CEAZA
Seasonal evolution of penitente glaciochemistry at Tapado Glacier, Northern Chile.
Sinclair, K. & MacDonell, S.
This study uses stable isotopes and major ions to examine the seasonal evolution of penitentes on the surface of Tapado Glacier, in the Norte Chico region of the Chilean Andes. A snow pit was sampled in November 2011, and penitentes were sampled during the summer (December 2011 and January 2012). The major ion load of the winter snowpack is dominated by Ca2+ (60%), SO42− (16%) and NO3− (13%), and there is little influence from marine air masses at the site, with most SO42−, Mg2+, Ca2+ and Na+, derived from non-sea salt sources. During the early ablation season we observe increases in stable isotope ratios and major ion concentrations (particularly lithic ions Na+, Mg2+ and Ca2+) in the upper reaches of penitentes, which is attributed to sublimation and the aeolian deposition of dust particles. In the late-summer, melt replaces sublimation as the dominant ablation process and results in smoothing of the stable isotope profile and the elution of major ions within the penitente snow and ice matrix. Copyright © 2015 John Wiley & Sons, Ltd.
Año: 2016
Palabras claves: Abiotic stress, adaptation, Andean crop, genetic variability, halophyte crop, nutritional properties, salinity.
Referencia APA: Sinclair, K. & MacDonell, S. (2016). Seasonal evolution of penitente glaciochemistry at Tapado Glacier, Northern Chile. Hydrol. Process., 30(2), 176-186.
Variability of 14C reservoir age and air–sea flux of CO2 in the Peru–Chile upwelling region during the past 12,000years.
Carré, M., Jackson, D., Maldonado, A., Chase, B., & Sachs, J.
The variability of radiocarbon marine reservoir age through time and space limits the accuracy of chronologies in marine paleo-environmental archives. We report here new radiocarbon reservoir ages (ΔR) from the central coast of Chile (~ 32°S) for the Holocene period and compare these values to existing reservoir age reconstructions from southern Peru and northern Chile. Late Holocene ΔR values show little variability from central Chile to Peru. Prior to 6000 cal yr BP, however, ΔR values were markedly increased in southern Peru and northern Chile, while similar or slightly lower-than-modern ΔR values were observed in central Chile. This extended dataset suggests that the early Holocene was characterized by a substantial increase in the latitudinal gradient of marine reservoir age between central and northern Chile. This change in the marine reservoir ages indicates that the early Holocene air–sea flux of CO2 could have been up to five times more intense than in the late Holocene in the Peruvian upwelling, while slightly reduced in central Chile. Our results show that oceanic circulation changes in the Humboldt system during the Holocene have substantially modified the air–sea carbon flux in this region.
Año: 2016
Palabras claves: Humboldt system; Reservoir age; Shell middens; Deglaciation; Radiocarbon; CO2.
Referencia APA: Carré, M., Jackson, D., Maldonado, A., Chase, B., & Sachs, J. (2016). Variability of 14C reservoir age and air–sea flux of CO2 in the Peru–Chile upwelling region during the past 12,000years. Quaternary Research, 85(1), 87-93.
Quinoa – a Model Crop for Understanding Salt-tolerance Mechanisms in Halophytes.
Ruiz, K., Biondi, S., Martínez, E., Orsini, F., Antognoni, F., & Jacobsen, S.
Quinoa (Chenopodium quinoa Willd.) is an ancient Andean crop that produces edible seeds and leaves. Quinoa's tolerance to salinity and other types of abiotic stresses provides it with high potential in a world where scarcity of water and increased soil salinization are important causes of crop failures. Due to its traditionally broad cultivation area (from Colombia to southern Chile), there is a wide range of quinoa cultivars adapted to specific conditions displaying a broad genetic variability in stress tolerance. In addition, being practically unique as a halophytic seed-producing crop with amazing nutritional properties, it is ideal as a model species for investigating morphological, cellular, physiological, and bio-molecular mechanisms of salinity tolerance. This review summarizes current knowledge of genotype-dependent variability in salinity responses and adaptive salt-tolerance mechanisms in quinoa. These include anatomical features and physiological aspects, such as osmotic adjustment through accumulation of ions, osmoprotectants, and sodium loading, transport, and storage, including the activity and gene expression of plasma and vacuolar membrane transporters. Finally, current knowledge regarding the effect of salinity on the nutritional properties of quinoa is discussed.
Año: 2016
Palabras claves: Abiotic stress, adaptation, Andean crop, genetic variability, halophyte crop, nutritional properties, salinity.
Referencia APA: Ruiz, K., Biondi, S., Martínez, E., Orsini, F., Antognoni, F., & Jacobsen, S. (2016). Quinoa – a Model Crop for Understanding Salt-tolerance Mechanisms in Halophytes. Plant Biosystems - An International Journal Dealing With All Aspects Of Plant Biology, 150(2), 357-371.
Molecular characterization of an inhibitor of NF-κB in the scallop Argopecten purpuratus: First insights into its role on antimicrobial peptide regulation in a mollusk.
Oyanedel, D., Gonzalez, R., Flores-Herrera, P., Brokordt, K., Rosa, R., Mercado, L., & Schmitt, P.
Inhibitors of nuclear factor kappa B (IκBs) are major control components of the Rel/NF-κB signaling pathway, a key regulator in the modulation of the expression of immune-related genes in vertebrates and invertebrates. The activation of the Rel/NF-κB signaling pathway depends largely in the degradation of IκB proteins and thus, IκBs are a main target for the identification of genes whose expression is controlled by Rel/NF-κB pathway. In order to identify such regulation in bivalve mollusks, the cDNA sequence encoding an IκB protein was characterized in the scallop Argopecten purpuratus, ApIκB. The cDNA sequence of ApIκB is comprised of 1480 nucleotides with a 1086 bp open reading frame encoding for 362 amino acids. Bioinformatics analysis showed that ApIκB displays the conserved features of IκB proteins. The deduced amino acid sequence consists of a 39.7 kDa protein, which has an N-terminal degradation motif, six ankyrin repeats and a C-terminal phosphorylation site motif. Phylogenetic analysis revealed a high degree of identity between ApIκB and other IκBs from mollusks, but also to arthropod cactus proteins and vertebrate IκBs. Tissue expression analysis indicated that ApIκB is expressed in all examined tissues and it is upregulated in circulating hemocytes from scallops challenged with the pathogenic Gram-negative bacterium Vibrio splendidus. After inhibiting ApIκB gene expression using the RNA interference technology, the gene expression of the antimicrobial peptide big defensin was upregulated in hemocytes from non-challenged scallops. Results suggest that ApIκB may control the expression of antimicrobial effectors such as big defensin via a putative Rel/NF-κB signaling pathway. This first evidence will help to deepen the knowledge of the Rel/NF-κB conserved pathway in scallops.
Año: 2016
Palabras claves: Signaling pathway; NF-κB pathway; Inhibition of nuclear factor kappa B; Antimicrobial peptide; Big defensin; Immunoregulation; Scallop; RNA interference.
Referencia APA: Oyanedel, D., Gonzalez, R., Flores-Herrera, P., Brokordt, K., Rosa, R., Mercado, L., & Schmitt, P. (2016). Molecular characterization of an inhibitor of NF-κB in the scallop Argopecten purpuratus: First insights into its role on antimicrobial peptide regulation in a mollusk. Fish & Shellfish Immunology, 52, 85-93.
Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile.
Garavelli, L., Colas, F., Verley, P., Kaplan, D., Yannicelli, B., & Lett, C.
In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future.
Año: 2016
Palabras claves: Fecundity, Hydrodynamics, Biophysics, Chile (country), Biological transport, Death rates, Marine biology.
Referencia APA: Garavelli, L., Colas, F., Verley, P., Kaplan, D., Yannicelli, B., & Lett, C. (2016). Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile. PLOS ONE, 11(1), e0146418.
South Pacific Integrated Ecosystem Studies meeting: toward conservation and sustainable use of marine resources in the South Pacific.
Parada, C., Frusher, S., Bustamante, R., Di Lorenzo, E., Bernal, P., & Cryer, M.Dunn, A., Garreaud, R., Gutierrez, M., Jennings, S., Montecinos, A., Neira, S., Quiñones, R.A., Takahashi, K., Tascheri, R., Yannicelli, B.
The South Pacfic region represents the world’s largest oceanic water mass and plays a signficant role in the earth’s climate systems. This region also contains the
largest group of island nations, most of whom are dependent on marine resources for their livelihoods. Several of the largest coastal and oceanic fisheries also
occur in this region (FAO, 2014). In addition, for the countries associated with the southern Pacfic Ocean region, the sea provides signficant social , cultural and
economic benfits, with many countries being heavily reliant on both coastal and oceanic marine resources (Bell et al., 2013). Increasing coastal populations and
climate change are expected to augment human demands on already fully exploited or over-exploi ted marine resources, threatening both food security and
sustainable livelihoods (Bell et al., 2011). Therefore, it is imperative that the science that describes and predicts linked biophysical and human systems is understood and developed to meet these needs. Climate change will have many impacts on marine ecosystems, with implications for end users including individuals, local communities, industries and governments. Improved scientfic support for policy and management decision-making in the face of these potential impacts is essential.
Año: 2016
Palabras claves:
Referencia APA: Parada, C., Frusher, S., Bustamante, R., Di Lorenzo, E., Bernal, P., & Cryer, M.Dunn, A., Garreaud, R., Gutierrez, M., Jennings, S., Montecinos, A., Neira, S., Quiñones, R.A., Takahashi, K., Tascheri, R., Yannicelli, B. (2016). South Pacific Integrated Ecosystem Studies meeting: toward conservation and sustainable use of marine resources in the South Pacific. Fish. Oceanogr., 25, 1-4.
Interannual variability in temporal patterns of Chlorophyll–a and their potential influence on the supply of mussel larvae to inner waters in northern Patagonia (41–44°S).
Lara, C., Saldías, G., Tapia, F., Iriarte, J., & Broitman, B.
Environmental forcing of biophysical processes can have deep influences on patterns of supply of planktonic larvae to benthic communities in coastal marine ecosystems. We investigated the role of environmental forcing following a recent interannual decrease in larval supply in the Inner Sea of Chiloé (41–45°S) using direct observations and environmental time series over the period 2003–2014. To examine the temporal structure of larval supply and potential associations with environmental forcing (approximated using satellite chlorophyll-a and sea surface temperature), we used wavelet analysis and lagged correlations to test the hypothesis of an association between larval availability and changes in the seasonal cycle of chlorophyll-a concentration, sea surface temperature, and relevant climate variability (Pacific Decadal Oscillation, El Niño-Southern Oscillation and Southern Annular Mode). Our results indicate that a weakening in the annual cycle of chlorophyll-a concentration and abnormally cold sea surface temperature during 2009–2010 can be related to the observed disruption in larval supply to the Inner Sea of Chiloé starting during the 2010–2011 season. The potential influence of climate variability is further discussed as the spatial extent and temporal persistence observed suggest that other ecological processes might have also been affected, and consequently, we suggest a link to transient large-scale climatic forcing.
Año: 2016
Palabras claves: Inner Sea of Chiloé; Mussel larvae; Chlorophyll-a; Sea surface temperature.
Referencia APA: Lara, C., Saldías, G., Tapia, F., Iriarte, J., & Broitman, B. (2016). Interannual variability in temporal patterns of Chlorophyll–a and their potential influence on the supply of mussel larvae to inner waters in northern Patagonia (41–44°S). Journal Of Marine Systems, 155, 11-18.
Effects of temperature and ocean acidification on shell characteristics of Argopecten purpuratus: implications for scallop aquaculture in an upwelling-influenced area.
Lagos, N., Benítez, S., Duarte, C., Lardies, M., Broitman, B., & Tapia, C. et al.
Coastal upwelling regions already constitute hot spots of ocean acidification as naturally acidified waters are brought to the surface. This effect could be exacerbated by ocean acidification and warming, both caused by rising concentrations of atmospheric CO2. Along the Chilean coast, upwelling supports highly productive fisheries and aquaculture activities. However, during recent years, there has been a documented decline in the national production of the native scallop Argopecten purpuratus. We assessed the combined effects of temperature and pCO2-driven ocean acidification on the growth rates and shell characteristics of this species farmed under the natural influence of upwelling waters occurring in northern Chile (30°S, Tongoy Bay). The experimental scenario representing current conditions (14°C, pH ~8.0) were typical of natural values recorded in Tongoy Bay, whilst conditions representing the low pH scenario were typical of an adjacent upwelling area (pH ~7.6). Shell thickness, weight, and biomass were reduced under low pH (pH ~7.7) and increased temperature (18°C) conditions. At ambient temperature (14°C) and low pH, scallops showed increased shell dissolution and low growth rates. However, elevated temperatures ameliorated the impacts of low pH, as evidenced by growth rates in both pH treatments at the higher temperature treatment that were not significantly different from the control treatment. The impact of low pH at current temperature on scallop growth suggests that the upwelling could increase the time required for scallops to reach marketable size. Mortality of farmed scallops is discussed in relation to our observations of multiple environmental stressors in this upwelling-influenced area.
Año: 2016
Palabras claves: Calcification, Shell growth, Scallop farming, Upwelling, Chile.
Referencia APA: Lagos, N., Benítez, S., Duarte, C., Lardies, M., Broitman, B., & Tapia, C. et al. (2016). Effects of temperature and ocean acidification on shell characteristics of Argopecten purpuratus: implications for scallop aquaculture in an upwelling-influenced area. Aquaculture Environment Interactions, 8, 357-370.
Artificial breakwaters as garbage bins: Structural complexity enhances anthropogenic litter accumulation in marine intertidal habitats.
Aguilera, M., Broitman, B., & Thiel, M.
Coastal urban infrastructures are proliferating across the world, but knowledge about their emergent impacts is still limited. Here, we provide evidence that urban artificial reefs have a high potential to accumulate the diverse forms of litter originating from anthropogenic activities around cities. We test the hypothesis that the structural complexity of urban breakwaters, when compared with adjacent natural rocky intertidal habitats, is a driver of anthropogenic litter accumulation. We determined litter abundances at seven sites (cities) and estimated the structural complexity in both urban breakwaters and adjacent natural habitats from northern to central Chile, spanning a latitudinal gradient of ∼15° (18°S to 33°S). Anthropogenic litter density was significantly higher in coastal breakwaters when compared to natural habitats (∼15.1 items m−2 on artificial reefs versus 7.4 items m−2 in natural habitats) at all study sites, a pattern that was temporally persistent. Different litter categories were more abundant on the artificial reefs than in natural habitats, with local human population density and breakwater extension contributing to increase the probabilities of litter occurrence by ∼10%. In addition, structural complexity was about two-fold higher on artificial reefs, with anthropogenic litter density being highest at intermediate levels of structural complexity. Therefore, the spatial structure characteristic of artificial reefs seems to enhance anthropogenic litter accumulation, also leading to higher residence time and degradation potential. Our study highlights the interaction between coastal urban habitat modification by establishment of artificial reefs, and pollution. This emergent phenomenon is an important issue to be considered in future management plans and the engineering of coastal ecosystems.
Año: 2016
Palabras claves: Artificial reefs; Anthropogenic litter; Rocky intertidal; Structural complexity; Shoreline.
Referencia APA: Aguilera, M., Broitman, B., & Thiel, M. (2016). Artificial breakwaters as garbage bins: Structural complexity enhances anthropogenic litter accumulation in marine intertidal habitats. Environmental Pollution, 214, 737-747.
Hydrologic Landscape Characterization for the Pacific Northwest, USA.
Leibowitz, S., Comeleo, R., Wigington, P., Weber, M., Sproles, E., & Sawicz, K.
We update the Wigington et al. (2013) hydrologic landscape (HL) approach to make it more broadly applicable and apply the revised approach to the Pacific Northwest (PNW; i.e., Oregon, Washington, and Idaho). Specific changes incorporated are the use of assessment units based on National Hydrography Dataset Plus V2 catchments, a modified snowmelt model validated over a broader area, an aquifer permeability index that does not require preexisting aquifer permeability maps, and aquifer and soil permeability classes based on uniform criteria. Comparison of Oregon results for the revised and original approaches found fewer and larger assessment units, loss of summer seasonality, and changes in rankings and proportions of aquifer and soil permeability classes. Differences could be explained by three factors: an increased assessment unit size, a reduced number of permeability classes, and use of smaller cutoff values for the permeability classes. The distributions of the revised HLs in five groups of Oregon rivers were similar to the original HLs but less variable. The improvements reported here should allow the revised HL approach to be applied more often in situations requiring hydrologic classification and allow greater confidence in results. We also apply the map results to the development of hydrologic landscape regions.
Año: 2016
Palabras claves: Hydrologic classification; hydrologic cycle; watersheds; rivers/streams; runoff; geospatial analysis; National Hydrography Dataset, NHD; Pacific Northwest.
Referencia APA: Leibowitz, S., Comeleo, R., Wigington, P., Weber, M., Sproles, E., & Sawicz, K. (2016). Hydrologic Landscape Characterization for the Pacific Northwest, USA. JAWRA Journal Of The American Water Resources Association, 52(2), 473-493. 1688.12402
Climatic characteristics of the semi-arid Coquimbo Region in Chile.
Montecinos, S., Gutiérrez, J., López-Cortés, F., & López, D.
The climate of the Coquimbo Region, north-central Chile is driven by atmospheric, oceanic and orographic factors. The southeast Pacific anticyclone, the cold Humboldt Current and the rugged topography that characterize the zone, determine thermally induced wind regimes and the formation of low stratocumulus along the coastline. Low precipitation and high solar radiation cause important climatic altitudinal gradients, especially on temperature and humidity, thus different climatic areas can be identified in the region. We summarized the general climatic characteristics of the study area and analyzed meteorological data to understand the behavior of the environmental variables. We used mesoscale modeling to evaluate the spatial characteristics of the mean air temperature, humidity and wind. These atmospheric variables present a strong elevation gradient. The particular topographic characteristics of the region favor the development of a thermally induced wind regime, where land and sea breezes and valley winds are observed.
Año: 2016
Palabras claves: Atmospheric modeling; Semi-arid zones; Desert.
Referencia APA: Montecinos, S., Gutiérrez, J., López-Cortés, F., & López, D. (2016). Climatic characteristics of the semi-arid Coquimbo Region in Chile. Journal Of Arid Environments, 126, 7-11.
Water deficit stress-induced changes in carbon and nitrogen partitioning in Chenopodium quinoa Willd.
Bascuñán-Godoy, L., Reguera, M., Abdel-Tawab, Y., & Blumwald, E.
Water deficit stress followed by re-watering during grain filling resulted in the induction of the ornithine pathway and in changes in Quinoa grain quality.
The genetic diversity of Chenopodium quinoa Willd. (Quinoa) is accompanied by an outstanding environmental adaptability and high nutritional properties of the grains. However, little is known about the biochemical and physiological mechanisms associated with the abiotic stress tolerance of Quinoa. Here, we characterized carbon and nitrogen metabolic changes in Quinoa leaves and grains in response to water deficit stress analyzing their impact on the grain quality of two lowland ecotypes (Faro and BO78). Differences in the stress recovery response were found between genotypes including changes in the activity of nitrogen assimilation-associated enzymes that resulted in differences in grain quality. Both genotypes showed a common strategy to overcome water stress including the stress-induced synthesis of reactive oxygen species scavengers and osmolytes. Particularly, water deficit stress induced the stimulation of the ornithine and raffinose pathways. Our results would suggest that the regulation of C- and N partitioning in Quinoa during grain filling could be used for the improvement of the grain quality without altering grain yields.
Año: 2016
Palabras claves: C and N partitioning, Grain nutritional quality, Ornithine pathway, Quinoa, ROS scavengers, Stress recovery, Source and sink interactions, Water deficit stress.
Referencia APA: Bascuñán-Godoy, L., Reguera, M., Abdel-Tawab, Y., & Blumwald, E. (2016). Water deficit stress-induced changes in carbon and nitrogen partitioning in Chenopodium quinoa Willd. Planta, 243(3), 591-603.