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Genetic differentiation between humpback whales (Megaptera novaeangliae) from Atlantic and Pacific breeding grounds of South America

Autores:

Cypriano-Souza, A. L., Engel, M. H., Caballero, S., Olavarría, C., Flórez-González, L., Capella, J., Steel, D., Sremba, A., Aguayo, A., Thiele, D., Baker, C. S. and Bonatto, S. L.

Resumen:

Humpback whales wintering in tropical waters along the Atlantic and Pacific coasts of the South American continent are thought to represent distinct populations or “stocks.” Here we present the first analysis of genetic differentiation and estimates of gene flow between these breeding stocks, based on both mitochondrial DNA (mtDNA) control region sequences (465 bp) and 16 microsatellite loci from samples collected off Brazil (n = 277) and Colombia (n = 148), as well as feeding areas near the western Antarctic Peninsula (n = 86). We found significant differentiation between Brazilian and Colombian breeding grounds at both mtDNA (FST = 0.058) and microsatellite (FST = 0.011) markers and corroborated previous studies showing genetic similarity between humpbacks from Colombia and those from Antarctic Peninsula feeding areas. Estimates of long-term gene flow between Brazil and Colombia were low to moderate, asymmetrical, and mostly mediated by males. Assignment procedures detected some cases of interchange and individuals of admixed ancestry between breeding grounds, indicating limited mixing of individuals between these stocks. Overall, results highlight the differentiation of humpback whale breeding populations with adjacent feeding grounds. This appears to be a remarkable example of fidelity to seasonal habitat in the absence of any contemporary barriers.

Año: 2017

Palabras claves: Megaptera novaeangliae; population genetic structure; microsatellites; mtDNA; migration; individual assignment

Referencia APA: Cypriano-Souza, A. L., Engel, M. H., Caballero, S., Olavarría, C., Flórez-González, L., Capella, J., Steel, D., Sremba, A., Aguayo, A., Thiele, D., Baker, C. S. and Bonatto, S. L. (2017). Genetic differentiation between humpback whales (Megaptera novaeangliae) from Atlantic and Pacific breeding grounds of South America. Mar Mam Sci, 33: 457–479. doi:10.1111/mms.12378

La quinua, un modelo de sistema agroalimentario saludable y sostenible

Autores:

Enrique Alfonso Martinez Mosqueira

Resumen:

Nuestro planeta vive cambios sociales y climáticos acelerados y de magnitudes sin precedentes. En particular desde la Revolución Industrial del siglo XVIII. Entre ellos, la agricultura y su industrialización significó que el trabajo de la tierra dejó de ser una actividad agroalimentaria benéfica e inocua y se tornó agresiva y erosiva. Hoy es parte importante de la degradación de la biodiversidad y de los cambios climáticos planetarios, contribuyendo en forma importante a incrementar los gases de efecto invernadero. La pequeña agricultura que no ha sido contaminada con las prácticas de aceleración de la productividad ni con el uso extremo de agroquímicos produce aun un 70% de la alimentación mundial y es un patrimonio vivo que no debe perderse. Entre ellos está la gente y el cultivo de la quinua, una planta de las culturas andinas. Este libro busca dar a conocer sus sorprendentes propiedades nutricionales y las formas en que este cultivo puede contribuir a ser un modelo para la salud de la tierra, de las plantas, de los campesinos y de los consumidores. Formando a su vez un sistema económico también más justo y más saludable para todos: un sistema agroalimentario más sostenible.

Año: 2017

Palabras claves: agricultura ecológica, cambio climático, desarrollo sustentable, nutrición, quinua, salud, sostenibilidad, economía transparente

Referencia APA: Martínez Mosqueira, E. (n.d.). La quinua, un modelo de sistema agroalimentario saludable y sostenible.

Surface winds off Peru-Chile: Observing closer to the coast from radar altimetry

Autores:

Astudillo, O., Dewitte, B., Mallet, M., Frappart, F., Rutllant, J., Ramos, M., Bravo, L., Goubanova, K. and Illig, S.

Resumen:

The near-shore surface mesoscale atmospheric circulation in the upwelling systems off Peru and Chile is influential on the Sea Surface Temperature through Ekman transport and pumping. There has been a debate whether or not the so-called “wind drop-off”, that is a shoreward decrease of the surface wind speed near the coast, can act as an effective forcing of upwelling through Ekman pumping. Although the wind drop-off has been simulated by high-resolution atmospheric models, it has not been well documented due to uncertainties in the scatterometry-derived wind estimates associated with land contamination. Here we use the along-track altimetry-derived surface wind speed data from ENVISAT, Jason-1, Jason-2, and SARAL satellites, to document the spatial variability of the mean wind drop-off near the coast as estimated from the inversion of the radar backscattering coefficient. The data are first calibrated so as to fit with the scatterometer observations of previous and current satellite missions (QuikSCAT, ASCAT). The calibrated data are then analyzed near the coast and a wind drop-off scale is estimated. The results indicate that the wind drop-off takes place all along the coast, though with a significant alongshore variability in its magnitude. Differences between products are shown to be related both to the differences in repeat cycle between the different altimetry missions and to the peculiarities of the coastline shape at the coastal latitudes of the incident tracks. The relative contribution of Ekman pumping and Ekman transport to the total transport is also estimated indicating a comparable contribution off Chile while transport associated to Ekman pumping is on average ~ 1.4 larger than Ekman transport off Peru. Despite the aliasing effect associated with the weak repetitivity of the satellite orbit and the high frequency variability of the winds in this region, the analysis suggests that the seasonal cycle of the surface winds near the coast could be resolved at least off Peru.

Año: 2017

Palabras claves: Satellite altimetry, Peru-Chile upwelling system, Coastal surface winds, Wind drop-off

Referencia APA: Astudillo, O., Dewitte, B., Mallet, M., Frappart, F., Rutllant, J., Ramos, M., Bravo, L., Goubanova, K. and Illig, S. (2017). Surface winds off Peru-Chile: Observing closer to the coast from radar altimetry. Remote Sensing of Environment, 191, pp.179-196.

Dynamic Interactions among Boundaries and the Expansion of Sustainable Aquaculture

Autores:

Broitman, B., Halpern, B., Gelcich, S., Lardies, M., Vargas, C., Vásquez-Lavín, F., Widdicombe, S. and Birchenough, S.

Resumen:

Aquaculture is the fastest growing food production system in the world, generating more than half of the global seafood harvested today. These type of activities are crucial to provide key nutritional components for humanity in the future as populations worldwide are increasing and the demands for securing food resources are imperative. Multiple socio-ecological factors such as weak regulations and focus on maximizing production limit production and threaten the sustainable growth of aquaculture. We present a novel policy framework to evaluate and pursue growth in aquaculture considering four boundaries: biological productivity, environmental constraints to that productivity, policy that inhibits or promotes different kinds of aquaculture, and social preferences that determine aquaculture markets. Using a range of scenarios, we have shown that sustainable growth in aquaculture requires simultaneous consideration of all four boundaries and the potential interactions between all of these options. Our proposed conceptual framework shows that to further expand the boundaries of aquaculture production, the policy focus must remain flexible to enable the adaptation of from single-boundary approaches. Our approach takes account of the current boundaries, helping to consider the adaptive policy, which is deemed as a necessary tool for considering the dynamic interactions among boundaries, thus addressing the problem of defining the evolving limits of sustainable aquaculture.

Año: 2017

Palabras claves: sustainability, aquaculture research, socioecology, molusks, fishes

Referencia APA: Broitman, B., Halpern, B., Gelcich, S., Lardies, M., Vargas, C., Vásquez-Lavín, F., Widdicombe, S. and Birchenough, S. (2017). Dynamic Interactions among Boundaries and the Expansion of Sustainable Aquaculture. Frontiers in Marine Science, 4.

Context-dependent functional dispersion across similar ranges of trait space covered by intertidal rocky shore communities

Autores:

Valdivia, N., Segovia-Rivera, V., Fica, E., Bonta, C., Aguilera, M., & Broitman, B.

Resumen:

Functional diversity is intimately linked with community assembly processes, but its large-scale patterns of variation are often not well understood. Here, we investigated the spatiotemporal changes in multiple trait dimensions (“trait space”) along vertical intertidal environmental stress gradients and across a landscape scale. We predicted that the range of the trait space covered by local assemblages (i.e., functional richness) and the dispersion in trait abundances (i.e., functional dispersion) should increase from high- to low-intertidal elevations, due to the decreasing influence of environmental filtering. The abundance of macrobenthic algae and invertebrates was estimated at four rocky shores spanning ca. 200 km of the coast over a 36-month period. Functional richness and dispersion were contrasted against matrix-swap models to remove any confounding effect of species richness on functional diversity. Random-slope models showed that functional richness and dispersion significantly increased from high- to low-intertidal heights, demonstrating that under harsh environmental conditions, the assemblages comprised similar abundances of functionally similar species (i.e., trait convergence), while that under milder conditions, the assemblages encompassed differing abundances of functionally dissimilar species (i.e., trait divergence). According to the Akaike information criteria, the relationship between local environmental stress and functional richness was persistent across sites and sampling times, while functional dispersion varied significantly. Environmental filtering therefore has persistent effects on the range of trait space covered by these assemblages, but context-dependent effects on the abundances of trait combinations within such range. Our results further suggest that natural and/or anthropogenic factors might have significant effects on the relative abundance of functional traits, despite that no trait addition or extinction is detected.

Año: 2017

Palabras claves: community assembly; desiccation; environmental filtering; functional beta-diversity; functional traits; marine; mesoscale; seasonal

Referencia APA: Valdivia, N., Segovia-Rivera, V., Fica, E., Bonta, C., Aguilera, M., & Broitman, B. (2017). Context-dependent functional dispersion across similar ranges of trait space covered by intertidal rocky shore communities. Ecology And Evolution, 7(6), 1882-1891. http://dx.doi.org/10.1002/ece3.2762

Species-specific responses to ocean acidification should account for local adaptation and adaptive plasticity

Autores:

Vargas, C., Lagos, N., Lardies, M., Duarte, C., Manríquez, P., & Aguilera, V., Broitman, B., Widdicombe, S., & Dupont, S.

Resumen:

Global stressors, such as ocean acidification, constitute a rapidly emerging and significant problem for marine organisms, ecosystem functioning and services. The coastal ecosystems of the Humboldt Current System (HCS) off Chile harbour a broad physical–chemical latitudinal and temporal gradient with considerable patchiness in local oceanographic conditions. This heterogeneity may, in turn, modulate the specific tolerances of organisms to climate stress in species with populations distributed along this environmental gradient. Negative response ratios are observed in species models (mussels, gastropods and planktonic copepods) exposed to changes in the partial pressure of CO2 (pCO2pCO2) far from the average and extreme pCO2pCO2 levels experienced in their native habitats. This variability in response between populations reveals the potential role of local adaptation and/or adaptive phenotypic plasticity in increasing resilience of species to environmental change. The growing use of standard ocean acidification scenarios and treatment levels in experimental protocols brings with it a danger that inter-population differences are confounded by the varying environmental conditions naturally experienced by different populations. Here, we propose the use of a simple index taking into account the natural pCO2pCO2 variability, for a better interpretation of the potential consequences of ocean acidification on species inhabiting variable coastal ecosystems. Using scenarios that take into account the natural variability will allow understanding of the limits to plasticity across organismal traits, populations and species.

Año: 2017

Palabras claves:

Referencia APA: Vargas, C., Lagos, N., Lardies, M., Duarte, C., Manríquez, P., & Aguilera, V., Broitman, B., Widdicombe, S., & Dupont, S. (2017). Species-specific responses to ocean acidification should account for local adaptation and adaptive plasticity. Nature Ecology & Evolution, 1(4), 0084. http://dx.doi.org/10.1038/s41559-017-0084

Molecular characterization of endophytic fungi associated with the roots of Chenopodium quinoa inhabiting the Atacama Desert, Chile.

Autores:

González-Teuber, M., Vilo, C., & Bascuñán-Godoy, L.

Resumen:

Plant roots can be highly colonized by fungal endophytes. This seems to be of particular importance for the survival of plants inhabiting stressful habitats. This study focused on the Identification of the fungal endophytic community associated with the roots of quinoa plants (Chenopodium quinoa) growing near the salt lakes of the Atacama Desert, Chile. One hundred endophytic fungi were isolated from healthy quinoa roots, and the internal transcribed spacer (ITS) region was sequenced for phylogenetic and taxonomic analysis. The isolates were classified into eleven genera and 21 distinct operational taxonomic units (OTUs). Despite a relatively high diversity of root endophytic fungi associated with quinoa plants, the fungal community was dominated by only the Ascomycota phyla. In addition, the most abundant genera were Penicillium, Phoma and Fusarium, which are common endophytes reported in plant roots. This study shows that roots of C. quinoa harbor a diverse group of endophytic fungi. Potential roles of these fungi in plant host tolerance to stressful conditions are discussed.

Año: 2017

Palabras claves: Fungal endophytes; Quinoa; Internal transcribed spacer; Phylogenetic analysis; Atacama Desert

Referencia APA: González-Teuber, M., Vilo, C., & Bascuñán-Godoy, L. (2017). Molecular characterization of endophytic fungi associated with the roots of Chenopodium quinoa inhabiting the Atacama Desert, Chile. Genomics Data, 11, 109-112. http://dx.doi.org/10.1016/j.gdata.2016.12.015

Rootstock effect on irrigated grapevine yield under arid climate conditions are explained by changes in traits related to light absorption of the scion

Autores:

Bascuñán-Godoy, L., Franck, N., Zamorano, D., Sanhueza, C., Carvajal, D., & Ibacache, A.

Resumen:


The purpose of this study was to investigate the mechanisms underlying the effect of rootstocks on table grapevines grown under irrigated conditions in the arid North macro-zone of Chile.

Grapevine cv. Red Globe grafted onto three rootstocks (Harmony, Saint George and Salt Creek) were studied Structural and physiological parameters were monitored at different phenological stages under optimal production conditions.

An outstanding yield increment brought about by the rootstocks Harmony and Salt Creek was correlated with increased individual leaf and specific leaf area, pruning weight (proxy for total leaf area), photosynthesis per unit leaf mass, sugar in leaves and root carbon reserves. In addition, these high yielding rootstocks induced higher contents of light-harvesting chlorophyll a/b protein of photosystem II and total chlorophyll in the leaves of the scion. No correlations of yield with traits involved in water use (relative water content or instantaneous water use efficiency) were observed.

The effects of rootstocks on the light capture capacity of the scion directly affected carbon assimilation and storage and, accordingly, yield. Therefore, the identified traits are valuable targets for screening and selecting yield efficient rootstocks for irrigated table grape production in arid zones.

Año: 2017

Palabras claves: Grapevine rootstock, Light capture, Photo synthesis, Pruning weight, Red Globe, Yield

Referencia APA: Bascuñán-Godoy, L., Franck, N., Zamorano, D., Sanhueza, C., Carvajal, D., & Ibacache, A. (2017). Rootstock effect on irrigated grapevine yield under arid climate conditions are explained by changes in traits related to light absorption of the scion. Scientia Horticulturae, 218, 284-292. http://dx.doi.org/10.1016/j.scienta.2017.02.034

Genotype by environment interactions, heritabilities and genetic correlations for productive traits of Haliotis rufescens

Autores:

Farías, W., Winkler, F., & Brokordt, K.

Resumen:

A critical aspect of a selective breeding program is whether responses of traits of interest are similar in different environments. The magnitude of the genotype by environment interaction (GEI) together with heritability (h2) accounts for this aspect. Despite the economic significance of abalones and the interest in genetic improvement programs for their cultivation, only one previous study has reported GEI estimations for this group of mollusks. The objective of the present study was to estimate h2 and the existence of GEI for growth traits of Haliotis rufescens cultivated in Chilean farms with different environmental and management conditions. A total of 2 cohorts (2007 and 2009) of 50 and 42 families of full sibs (FS), respectively, were used. Replicates of each FS family of the 2007 cohort were distributed in two farms in the northern region of the country and were evaluated after 1 and 2 years of cultivation. For the 2009 cohort, replicates of each family were distributed in a farm in the northern region and a farm in the southern region of the country. The estimated h2 values were significant for all traits, with the length and width of the shell and total weight varying primarily by cohort between 0.22–0.62, 0.16–0.58 and 0.40–0.53, respectively. The genetic correlations (rG) between traits were all higher than 0.82. The expected correlated responses for improving the total weight using the shell length as a selection criterion predict a selection gain (14–51%) similar to what would be obtained by selecting directly for weight (16–51%) in all environments examined. Thus, indirect selection by shell length and the direct use of total weight as a selection criterion would yield similar effects in terms of the increase in weight. High rG, not significantly different from 1, were observed for the analyzed traits between replicates of the families in any of the farms compared, both within the northern region and between the northern and southern regions of the country. These high rG were indicative of non-significant GEI for the analyzed traits. Therefore, results suggest that one selective breeding program could provide improved red abalone for the industry in Chile with consistent results between farms located in different environments.

Año: 2017

Palabras claves: Abalone, Aquaculture, Breeding, Heritability, Genetic correlation, Genotype by environment interaction

Referencia APA: Farías, W., Winkler, F., & Brokordt, K. (2017). Genotype by environment interactions, heritabilities and genetic correlations for productive traits of Haliotis rufescens. Aquaculture, 473, 407-416. http://dx.doi.org/10.1016/j.aquaculture.2017.02.030

Future snow? A spatial-probabilistic assessment of the extraordinarily low snowpacks of 2014 and 2015 in the Oregon Cascades

Autores:

Sproles, E., Roth, T., & Nolin, A.

Resumen:

In the Pacific Northwest, USA, the extraordinarily low snowpacks of winters 2013–2014 and 2014–2015 stressed regional water resources and the socialenvironmental system. We introduce two new approaches to better understand how seasonal snow water storage during these two winters would compare to snow water storage under warmer climate conditions. The first approach calculates a spatial-probabilistic metric representing the likelihood that the snow water storage of 2013–2014 and 2014–2015 would occur under +2◦C perturbed climate conditions. We computed snow water storage (basin-wide and across elevations) and the ratio of snow water equivalent to cumulative precipitation (across elevations) for the McKenzie River basin (3041 km2), a major tributary to the Willamette River in Oregon, USA. We applied these computations to calculate the occurrence probability for similarly low snow water storage under climate warming. Results suggest that, relative to +2
◦C conditions, basin-wide snow water storage during winter 2013–2014 would be above average, while that of winter 2014–2015 would be far below average. Snow water storage on 1 April corresponds to a 42 % (2013–2014) and 92 % (2014–2015) probability of being met or exceeded in any given year. The second approach introduces the concept of snow analogs to improve the anticipatory capacity of climate change impacts on snow-derived water resources. The use of a spatial-probabilistic approach and snow analogs provide new methods of assessing basin-wide snow water storage in a non-stationary climate and are readily applicable in other snow-dominated watersheds.

Año: 2017

Palabras claves:

Referencia APA: Sproles, E., Roth, T., & Nolin, A. (2017). Future snow? A spatial-probabilistic assessment of the extraordinarily low snowpacks of 2014 and 2015 in the Oregon Cascades. The Cryosphere, 11(1), 331-341. http://dx.doi.org/10.5194/tc-11-331-2017

Surface water quality in a sulfide mineral-rich arid zone in North-Central Chile: Learning from a complex past, addressing an uncertain future

Autores:

Flores, M., Núñez, J., Oyarzún, J., Freixas, G., Maturana, H., & Oyarzún, R.

Resumen:

This study presents an analysis of up to 30 years of hydrological variables and selected water quality parameters (pH, SO4, Fe, Cu, and As) in the upper area of the Elqui River basin in North‐Central Chile. A correlation analysis determined statistically significant positive relationship for SO4‐Cu, Fe‐As, and Fe‐Cu. In terms of historical behaviour, no statistically significant
trends were detected for precipitation or temperature. In contrast, for flow, there is an overall decreasing pattern for the entire area of study, although only in one case this trend was statistically significant. Along with the aforementioned analysis, a characterization of the flow‐water quality relationships is considered for the time period analyzed. Although erratic behaviours were confirmed, a negative (i.e., inverse) flow‐concentration relationship was identified for SO4, a positive (i.e., direct) relationship for Fe, and undefined relationships for As and Cu were obtained.
From these analyses and based on previous studies on projections regarding climate change for the Andean region, and in particular for the upper Elqui zone, an estimation of the possible effects of the change in water regimes on water quality in the area of study is developed. It is likely that a decrease in surface flow, as a consequence of climate change could translate into improvements in water quality in terms of Fe and eventually As and Cu, but into an impairment in the case of
SO4. In any case, this is a complex situation that demands special attention in the face of industrial activities that could be developed in tributaries like the Claro River, which currently play an important role in depurating or diluting contaminants in the waters of the Elqui River. Finally, it should be noted that this study addresses an issue that goes beyond the local interest and could be used as a reference to compare other transitional environments containing sulphide ores or areas of hydrothermal alterations, which are considered to be highly vulnerable to climate change and variability.

Año: 2016

Palabras claves: acid rock drainage, Andean river, arid zone, Coquimbo region

Referencia APA: Flores, M., Núñez, J., Oyarzún, J., Freixas, G., Maturana, H., & Oyarzún, R. (2016). Surface water quality in a sulfide mineral-rich arid zone in North-Central Chile: Learning from a complex past, addressing an uncertain future. Hydrological Processes, 31(3), 498-513. http://dx.doi.org/10.1002/hyp.11086

Effects of elevated carbon dioxide and temperature on locomotion and the repeatability of lateralization in a keystone marine mollusc

Autores:

Domenici, P., Torres, R., & Manríquez, P.

Resumen:

Recent work has shown that the behaviour of marine organisms can be affected by elevated PCO2 , although little is known about the effect of multiple stressors. We therefore investigated the effect of elevated PCO2 and temperature on locomotion and behaviour during prey searching in the marine gastropod Concholepas concholepas, a predator characteristic of the southeastern Pacific coast. Movement duration, decision time, route finding and lateralization were measured using a T-maze tank with a prey positioned behind a barrier. Four treatments, representing present day and near-future scenarios of ocean acidification and warming were used in rearing the individuals for 6 months. Regardless of the treatment, no significant differences were found in relative and absolute lateralization before and after exposure for 6 months. However, relative lateralization was not repeatable for animals tested after 6 months at elevated PCO2 at both experimental temperatures, whereas it was repeatable in individuals kept at the present day level of PCO2. We suggest that these effects may be related to a behavioural malfunction caused by elevated PCO2. Movement duration, decision time and route finding were not repeatable. However, movement duration and decision time increased and route finding decreased in elevated PCO2 (at 15°C), suggesting that elevated PCO2 has negative effects on the locomotor and sensory performance of C. concholepas in the presence of a prey odour, thereby decreasing their ability to forage efficiently.

Año: 2017

Palabras claves: Ocean acidification, Temperature, Gastropod locomotion, Lateralization, Route finding, Concholepas concholepas.

Referencia APA: Domenici, P., Torres, R., & Manríquez, P. (2017). Effects of elevated carbon dioxide and temperature on locomotion and the repeatability of lateralization in a keystone marine mollusc. The Journal Of Experimental Biology, 220(4), 667-676. http://dx.doi.org/10.1242/jeb.151779