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Quinoa biodiversity and sustainability for food security under climate change.

Autores:

Ruiz, K., Biondi, S., Oses, R., Acuña-Rodríguez, I., Antognoni, F., & Martinez-Mosqueira, E. et al.

Resumen:

Climate change is rapidly degrading the conditions of crop production. For instance, increasing salinization and aridity is forecasted to increase in most parts of the world. As a consequence, new stress-tolerant species and genotypes must be identified and used for future agriculture. Stress-tolerant species exist but are actually underutilized and neglected. Many stress-tolerant species are indeed traditional crops that are only cultivated by farmers at a local scale. Those species have a high biodiversity value. Besides, the human population will probably reach nine billion within coming decades. To keep pace with population growth, food production must increase dramatically despite the limited availability of cultivable land and water. Here, we review the benefits of quinoa, Chenopodium quinoa Willd., a seed crop that has endured the harsh bioclimatic conditions of the Andes since ancient times. Although the crop is still mainly produced in Bolivia and Peru, agronomic trials and cultivation are spreading to many other countries. Quinoa maintains productivity on rather poor soils and under conditions of water shortage and high salinity. Moreover, quinoa seeds are an exceptionally nutritious food source, owing to their high protein content with all essential amino acids, lack of gluten, and high content of several minerals, e.g., Ca, Mg, Fe, and health-promoting compounds such as flavonoids. Quinoa has a vast genetic diversity resulting from its fragmented and localized production over the centuries in the Andean region, from Ecuador to southern Chile, and from sea level to the altiplano. Quinoa can be adapted to diverse agroecological conditions worldwide. Year 2013 has therefore been declared the International Year of Quinoa by the United Nations Food and Agriculture Organization. Here, we review the main characteristics of quinoa, its origin and genetic diversity, its exceptional tolerance to drought and salinity, its nutritional properties, the reasons why this crop can offer several ecosystem services, and the role of Andean farmers in preserving its agrobiodiversity. Finally, we propose a schematic model integrating the fundamental factors that should determine the future utilization of quinoa, in terms of food security, biodiversity conservation, and cultural identity.

Año: 2014

Palabras claves: Agrobiodiversity, Quinoa, Food security, Food quality, Stress tolerance, Andean farmers, Sustainability.

Referencia APA: Ruiz, K., Biondi, S., Oses, R., Acuña-Rodríguez, I., Antognoni, F., & Martinez-Mosqueira, E. et al. (2014). Quinoa biodiversity and sustainability for food security under climate change. A review. Agronomy For Sustainable Development, 34(2), 349-359.

Water Quality Assessment of the Mining-Impacted Elqui River Basin, Chile.

Autores:

Ribeiro, L., Kretschmer, N., Nascimento, J., Buxo, A., Rötting, T., & Soto, G., Soto, M., Oyarzún, J., Maturana, H., Oyarzún, R.

Resumen:

Multivariate data analysis techniques were used to identify the interrelationships between the physical–chemical analyses of 22 parameters sampled monthly from 1991 to 2007 at 16 monitoring stations along the Elqui river and its tributaries to characterize the scale of the geogenic and anthropogenic impacts on the river’s water quality. Principal component analysis was used to identify the differences and similarities between variables in the watershed. Factorial indices, computed to highlight the sections of the river and tributaries more influenced by hydrothermal, mining or agricultural activities, made it possible to synthesize groups of parameters with similar characteristics into a single value.

Año: 2014

Palabras claves: Acid drainage, Arid zones, Elqui river, Mining pollution, PCA.

Referencia APA: Ribeiro, L., Kretschmer, N., Nascimento, J., Buxo, A., Rötting, T., & Soto, G., Soto, M., Oyarzún, J., Maturana, H., Oyarzún, R. (2014). Water Quality Assessment of the Mining-Impacted Elqui River Basin, Chile. Mine Water And The Environment, 33(2), 165-176.

EltonTraits 1.0: Species-level foraging attributes of the world’s birds and mammals.

Autores:

Wilman, H., Belmaker, J., Simpson, J., de la Rosa, C., Rivadeneira, M., & Jetz, W.

Resumen:

Species are characterized by physiological, behavioral, and ecological attributes that are all subject to varying evolutionary and ecological constraints and jointly determine species' role and function in ecosystems. Attributes such as diet, foraging strata, foraging time, and body size, in particular, characterize a large portion of the “Eltonian” niches of species. Here we present a global species-level compilation of these key attributes for all 9993 and 5400 extant bird and mammal species derived from key literature sources. Global handbooks and monographs allowed the consistent sourcing of attributes for most species. For diet and foraging stratum we followed a defined protocol to translate the verbal descriptions into standardized, semiquantitative information about relative importance of different categories. Together with body size (continuous) and activity time (categorical) this enables a much finer distinction of species' foraging ecology than typical categorical guild assignments allow. Attributes lacking information for specific species are flagged, and interpolated values based on taxonomy are provided instead. The presented data set is limited by, among others, these select cases missing observed data, by errors and uncertainty in the expert assessment as presented in the literature, and by the lack of intraspecific information. However, the standardized and transparent nature and complete global coverage of the data set should support an array of potential studies in biogeography, community ecology, macroevolution, global change biology, and conservation. Potential uses include comparative work involving these traits as focal or secondary variables, ecological research on the trait or trophic structure of communities, or conservation science concerned with the loss of function among species or in ecosystems in a changing world. We hope that this publication will spur the sharing, collaborative curation, and extension of data to the benefit of a more integrative, rigorous, and global biodiversity science.

Año: 2014

Palabras claves: Bird; body size; diet; eco-informatics; foraging; function; mammal; mass; niche; stratum; traits; vertebrate.

Referencia APA: Wilman, H., Belmaker, J., Simpson, J., de la Rosa, C., Rivadeneira, M., & Jetz, W. (2014). EltonTraits 1.0: Species-level foraging attributes of the world's birds and mammals. Ecology, 95(7), 2027-2027.

Nutritional status affects the capacity of the snail Concholepas concholepas to synthesize Hsp70 when exposed to stressors associated with tidal regimes in the intertidal zone.

Autores:

Jeno, K. & Brokordt, K.

Resumen:

Synthesis of the heat shock protein Hsp70 is one of the most important physiological mechanisms that intertidal organisms possess to counteract damage to macromolecules caused by stressors associated with the tidal cycle. However, the synthesis and activity of Hsp70 involves an elevated energetic cost. We evaluated the effect of the nutritional status (fed vs. starved for 2 weeks) of juvenile Concholepas concholepas mollusc on their capacity to synthesize Hsp70 during emersion (i.e. low tide) and immersion (i.e. high tide) at high temperatures (24 °C, e.g. summer conditions) and at low temperatures (7 °C, e.g. winter conditions). In addition, we evaluated whether Hsp70 is induced directly upon exposure to stress (emersion) or during recovery (re-immersion). Starvation decreased the content of stored energy substrates of juveniles as well as their ability to synthesize Hsp70 during emersion under thermal stress, especially at high temperatures. Additionally, analysis of environmental factors associated with laboratory simulation of tidal regimes indicated that juveniles in starvation, in contrast to fed juveniles, did not significantly increase their levels of Hsp70 during cold emersion (7 °C) or warm emersion (24 °C) or upon re-immersion. Induction of Hsp70 occurred during exposure to stress (low-tide conditions) and not when juveniles returned to “normal” conditions (high-tide conditions). Thus, the synthesis of Hsp70 for the juveniles of this intertidal snail species was coordinated and adapted to the tidal cycle, and the species responds in a similar way to hot and cold emersion conditions. The observed levels of Hsp70 reflect the ability of the individual to synthesize these proteins, which is dependent on the nutritional status of the individual.

Año: 2014

Palabras claves:

Referencia APA: Jeno, K. & Brokordt, K. (2014). Nutritional status affects the capacity of the snail Concholepas concholepas to synthesize Hsp70 when exposed to stressors associated with tidal regimes in the intertidal zone. Marine Biology, 161(5), 1039-1049.

Glacier meltwater flow paths and storage in a geomorphologically complex glacial foreland: The case of the Tapado glacier, dry Andes of Chile (30°S).

Autores:

Pourrier, J., Jourde, H., Kinnard, C., Gascoin, S., & Monnier, S.

Resumen:

The Tapado catchment is located in the upper Elqui river basin (4000–5550 m) in northern Chile. It comprises the Tapado glacial complex, which is an assemblage of the Tapado glacier and the glacial foreland (debris-covered glacier, rock glacier, and moraines). Although the hydrological functioning of this catchment is poorly known, it is assumed to actively supply water to the lower semi-arid areas of the Elqui river basin. To improve our knowledge of the interactions and water transfers between the cryospheric compartment (glacier, debris-covered glacier, and rock glacier) and the hydrological compartment (aquifers, streams), the results of monitoring of meteorological conditions, as well as discharge, conductivity and temperature of streams and springs located in the Tapado catchment were analyzed. The hydrological results are compared to results inferred from a ground penetrating radar (GPR) survey of the underground structure of the glacial foreland. Water production from the Tapado glacier was shown to be highly correlated with daily and monthly weather conditions, particularly solar radiation and temperature. The resulting daily and monthly streamflow cycles were buffered by the glacial foreland, where underground transfers took place through complex flow paths. However, the development of a thermokarst drainage network in a portion of the glacial foreland enabled rapid concentrated water transfers that reduced the buffer effect. The glacial foreland was shown to act as a reservoir, storing water during high melt periods and supplying water to downstream compartments during low melt periods. GPR observations revealed the heterogeneity of the internal structure of the glacial foreland, which is composed of a mixture of ice and rock debris mixture, with variable spatial ice content, including massive ice lenses. This heterogeneity may explain the abovementioned hydrological behaviors. Finally, calculation of a partial hydrological budget confirmed the importance of the Tapado catchment in supplying water to lower areas of the Elqui river basin. Water production from, and transfer through, cryospheric compartments, and its subsequent interactions with hydrological compartments are key processes driving the summer water supply from the Tapado catchment.

Año: 2014

Palabras claves: Cryosphere hydrology; Debris-covered glacier; Rock glacier; Thermokarst; Water transfers; Semiarid Andes.

Referencia APA: Pourrier, J., Jourde, H., Kinnard, C., Gascoin, S., & Monnier, S. (2014). Glacier meltwater flow paths and storage in a geomorphologically complex glacial foreland: The case of the Tapado glacier, dry Andes of Chile (30°S). Journal Of Hydrology, 519, 1068-1083.

Daidzein and Genistein contents in seeds of quinoa (Chenopodium quinoa Willd.) from local ecotypes grown in arid Chile.

Autores:

Lutz, M., Martínez, A., & Martínez, E.

Resumen:

The contents of bioactive compounds of quinoa (Chenopodium quinoa Willd.) are poorly known. We analyzed two isoflavones (daidzein and genistein) by HPLC in three local ecotypes of quinoa seeds from three different geographical and genetic regions in Chile: (a) Extreme North, with prevailing conditions of high temperature and dryness (local ecotype R49); (b) Center, with milder climate (local ecotype UdeC9); and (c) South, with cold, humid environment (local ecotype BO78). Genetic-driven differences among cultivars were tested by homogenizing the culture conditions of the three seed sources. In addition, seven commercial samples of quinoa purchased at local food markets were analyzed and compared to our experimental harvested seeds. In all samples daidzein content was higher than genistein (P < 0.05). The northern ecotype R49 exhibited higher content of isoflavones compared with the other two (UdeC9 and BO78), all grown under the same experimental conditions. Daidzein ranged from 1.15 (R49) to 0.70 (BO78) mg/100 g, while genistein varied from 0.25 (R49) to 0.05 (UdeC9) mg/100 g. Ecotype R49 had 1.6 and 1.7 fold higher daidzein contents than UdeC9 and BO78, respectively (P < 0.05). In the commercial samples, the daidzein/genistein ratio ranged from 25.2 to 3.9, daidzein ranged from 2.05 to 0.78 mg/100 g, and genistein ranged from 0.41 to 0.04 mg/100 g. To the best of our knowledge, this is the first report on the contents of daidzein and genistein in quinoa seeds. The study demonstrates that, besides its well-recognized nutritional value, quinoa possesses an excellent potential as a source of these health-promoting bioactive compounds.

Año: 2013

Palabras claves: Quinoa; Daidzein; Genistein; Isoflavones; Ecotypes.

Referencia APA: Lutz, M., Martínez, A., & Martínez, E. (2013). Daidzein and Genistein contents in seeds of quinoa (Chenopodium quinoa Willd.) from local ecotypes grown in arid Chile. Industrial Crops And Products, 49, 117-121.

Importance of geochemical factors in determining distribution patterns of aquatic invertebrates in mountain streams south of the Atacama Desert, Chile.

Autores:

Alvial, I., Orth, K., Durán, B., Álvarez, E., & Squeo, F.

Resumen:

The ecology of macroinvertebrate communities in arid regions is still poorly understood. Here we examined how the community structure varied at spatial and temporal scales in streams and tributaries of the Huasco River in semi-arid region of Northern Chile. We expected that macroinvertebrate distribution may be responding to natural processes of mineralization described for Chilean semiarid basins. The relationships among biotic and abiotic variables were assessed through multivariate techniques (principal component analysis, non-metric multidimensional scaling, canonical correspondence analysis), and a two-way analysis of similarity was used to evaluate differences between basins and years (2007, 2008, and 2009). Significant differences in community structure and physical–chemical variables between basins (Del Carmen and Del Tránsito) were found, but not between years. Altitude, Mn, Al, Ca, Na, HCO3, and dissolved oxygen were the variables that best accounted for the communities distribution. In particular, high metals concentration in El Transito basin should determine low density and diversity of macroinvertebrates. Chironomidae, Ephydridae, and Glossiphoniidae were associated to waters with high metals content and acidic pH, whereas Baetidae, Hydroptilidae, and Blephariceridae were associated to sites with more favorable physical–chemical conditions. These results contribute to understand the ecological patterns of macroinvertebrates in arid regions and should lead to conservation and monitoring plans for this remote place.

Año: 2013

Palabras claves: Huasco basin, Desert climate, Macroinvertebrates, Biomonitoring, Habitat variables, Handling editor: Koen Martens

Referencia APA: Alvial, I., Orth, K., Durán, B., Álvarez, E., & Squeo, F. (2013). Importance of geochemical factors in determining distribution patterns of aquatic invertebrates in mountain streams south of the Atacama Desert, Chile. Hydrobiologia, 709(1), 11-25.

Estimating Spatial Distribution of Air Temperature from Meteorological Stations Using Atmospheric Model.

Autores:

Montecinos, S., Bascuñán-Godoy, L., Salinas, P., Astudillo, O., & Lopez, D.

Resumen:

Planning agricultural procedures needs to take into account meteorological conditions. However, because of high associated costs, the density of meteorological stations is often not enough to cover all the cultivated or potentially cultivated areas. In this article we present a methodology to estimate seasonal maximum and minimum mean temperature in cultivated area using data registered in a sole or a few meteorological stations. The procedure is based on mesoscale modeling, which allows meteorological variables to be spatially distributed considering synoptic data and local characteristics.

Simulated daily cycle of temperature was compared with data registered at six meteorological stations located in the cultivated floor of the semiarid Limari Valley (Chile, 31°S). Although in some cases the simulated temperature differs in about 2°C with the observed one, a good fit between model results and experimental data was observed. Using the simulated seasonal minimum and maximum mean temperature fields, maps of temperature differences with respect to a reference station were drawn. In order to observe the influence of the orography on the lapse rate around a station, the methodology was applied for two reference stations located in places with different orographic characteristics. Results for winter and summer seasons are shown.

These generated maps can be used by farmers and agricultural planners to obtain information of seasonal minimum and maximum mean temperature from a station in any site of the cultivated area. This technique is a good alternative to obtain meteorological information at low costs, contributing to territorial planning for climate resilient agriculture sustainability.

Año: 2013

Palabras claves:

Referencia APA: Montecinos, S., Bascuñán-Godoy, L., Salinas, P., Astudillo, O., & Lopez, D. (2013). Estimating Spatial Distribution of Air Temperature from Meteorological Stations Using Atmospheric Model. Journal Of Agricultural Science, 5(2).

Positive interactions between the lichen Usnea antarctica (Parmeliaceae) and the native flora in Maritime Antarctica.

Autores:

Molina-Montenegro, M., Ricote-Martínez, N., Muñoz-Ramírez, C., Gómez-González, S., Torres-Díaz, C., Salgado-Luarte, C., & Gianoli, E.

Resumen:

Eight out of 13 species were positively associated with cushions of the widespread lichen U. antarctica, while only one species (U. aurantiaco-atra) showed a negative association with U. antarctica. Survival of Deschampsia was enhanced when growing associated with U. antarctica cushions. Our results indicate that cushions ameliorated the extreme conditions of Antarctic islands through increased temperature and soil moisture, decreased radiation and evaporative water loss and increased nutrient availability.

Año: 2013

Palabras claves: Antarctica; Deschampsia antarctica ; Facilitation; Global warming; Lichens; Mosses; Nurse effect.

Referencia APA: Molina-Montenegro, M., Ricote-Martínez, N., Muñoz-Ramírez, C., Gómez-González, S., Torres-Díaz, C., Salgado-Luarte, C., & Gianoli, E. (2013). Positive interactions between the lichen Usnea antarctica (Parmeliaceae) and the native flora in Maritime Antarctica. J Veg Sci, 24(3), 463-472. http://dx.doi.org/10.1111/j.1654-1103.2012.01480.x

Environmental Hypoxia Reduces the Escape Response Capacity of Juvenile and Adult Scallops Argopecten purpuratus.

Autores:

Brokordt, K., Pérez, H., & Campos, F.

Resumen:

Natural beds and cultures of the scallop Argopecten purpuratus are exposed to hypoxia periodically because they are located near upwelling zones. We evaluated the effects of environmental hypoxia on juvenile and adult scallops' escape responses and recovery capacities using 3 different hypoxic cycle (i.e., a gradual decrease and increase of dissolved oxygen) trials. Trials 1 and 2 consisted of single (1-day) hypoxic cycles; trial 3 included exposure to several consecutive daily hypoxic cycles over 7 days, which occurs in the natural environment. Trial 1 evaluated the combined effects of energy demands from escape responses and metabolism on escape responses. during environmental hypoxia. Trial 2 evaluated only the effect of environmental hypoxia on the escape responses. Before and after the hypoxic cycles, the scallops were exposed to their main predator, the sea star Meyenaster gelatinosus. We evaluated 6 indicators of the scallops' escape response: reaction time, the total number of claps, duration of the clapping response until exhaustion, clapping speed, the proportion of claps, and recovery clapping rate after a recuperation of 5 min or 10 min (for juveniles and adults, respectively). The combined effect of functional and environmental hypoxia (trial 1) affected both juvenile and adult escape responses, with a reduction in their number of claps (15% and 25%, respectively), the clapping rate in juveniles (17%), and the clapping time in adults (19%). However, environmental hypoxia alone (trial 2) affected juvenile escape responses only, with a reduction in their number of claps (18%) and clapping rate (17%). After hypoxic exposure in trial 3, adults only showed a reduced escape capacity (clap number and clapping time of 16% and 17%, respectively), although both adult and juvenile scallops had a reduced capacity to recuperate their initial clap number (18% and 23%, respectively) and clapping rate (21% and 17%, respectively). Recovery capacity was associated with a strong reduction in phasic muscle carbohydrates during this period. Overall, hypoxia reduced the escape capacity of A. purpuratus, which may implicate a higher vulnerability to predation (for natural populations) and a decreased physiological status to support other stress factors (for cultured or natural populations).

Año: 2013

Palabras claves: Hypoxia, scallops, escape response, Argopecten purpuratus.

Referencia APA: Brokordt, K., Pérez, H., & Campos, F. (2013). Environmental Hypoxia Reduces the Escape Response Capacity of Juvenile and Adult Scallops Argopecten purpuratus. Journal Of Shellfish Research, 32(2), 369-376

Wind effects on snow cover in Pascua-Lama, Dry Andes of Chile.

Autores:

Gascoin, S., Lhermitte, S., Kinnard, C., Bortels, K., & Liston, G.

Resumen:

We present the first application of a distributed snow model (SnowModel) in the instrumented site of Pascua-Lama in the Dry Andes (2600–5630 m above sea level, 29° S). A model experiment was performed to assess the effect of wind on the snow cover patterns. A particular objective was to evaluate the role of blowing snow on the glacier formation. The model was run using the data from 11 weather stations over a complete snow season. First, a cross-validation of the meteorological variables interpolation model (MicroMet submodel) was performed to evaluate the performance of the simulated meteorological forcing. Secondly, two SnowModel simulations were set up: one without and the other with the wind transport submodel (SnowTran-3D). Results from both simulations were compared with in situ snow depth measurements and remotely sensed snow cover data. The inclusion of SnowTran-3D does not change the fact that the model is unable to capture the small-scale snow depth spatial variability (as captured by in situ snow depth sensors). However, remote sensing data (MODIS daily snow product) indicate that at broader scales the wind module produced an improved representation of the snow distribution near the glaciers (2-D correlation coefficient increased from R = 0.04 to R = 0.27). The model outputs show that a key process is the sublimation of blowing snow, which amounts to 18% of the total ablation over the whole study area, with a high spatial variability. The effect of snow drift is more visible on the glaciers, where wind-transported snow accumulates preferentially. Net deposition occurred for 43% of the glacier grid points, whereas it is only 23% of non-glacier grid points located above the minimum glacier altitude (4475 m).

Año: 2013

Palabras claves: Snow; Glacier; Wind; Sublimation; Andes; MODIS.

Referencia APA: Gascoin, S., Lhermitte, S., Kinnard, C., Bortels, K., & Liston, G. (2013). Wind effects on snow cover in Pascua-Lama, Dry Andes of Chile. Advances In Water Resources, 55, 25-39.

Barotropic and baroclinic semidiurnal tidal currents in two contrasting coastal upwelling zones of Chile.

Autores:

Bravo, L., Ramos, M., Sobarzo, M., Pizarro, O., & Valle-Levinson, A.

Resumen:

Current velocity observations from the continental shelves of Coquimbo (~30°S) and Concepcion (~36°30'S), central Chile, were analyzed to evaluate the role of water column stratification and shelf width on baroclinic semidiurnal tidal currents. Semidiurnal barotropic currents off both zones were typically < 5 cm/s, but depth-dependent semidiurnal flows could exceed 10 cm s-1 during stratified conditions. Both zones are recognized as pronounced upwelling centers, with maximum upwelling-favorable winds in spring and summer, respectively. At the northern zone, stratification was mainly controlled by temperature differences between surface and bottom waters with maximum stratification during summer. The southern zone showed more stratification during winter because of freshwater input from local rivers. Consequently, greater variability in the baroclinic semidiurnal currents was observed during summer at the northern continental shelf and in winter at the south. In both regions, much of the semidiurnal variability was consistent with an internal wave's first baroclinic mode of wavelengths of ~10–13 km. Nevertheless, during the period of maximum energy fluxes off the north, the second baroclinic mode (wavelength ~7 km) was also important and matched periods of low upwelling index (relaxation of upwelling favorable winds). Typical energy fluxes during summer integrated in the water column, related to the semidiurnal internal tides were 0.12 W/m of the northern site and 0.1 W/m off the southern site. Possible sites of internal wave generation off the south were the Biobío submarine canyon and the slope/shelf break, while off the north, the generation site was the slope/shelf break.

Año: 2013

Palabras claves: Baroclinic waves; semidiurnal; energy flux.

Referencia APA: Bravo, L., Ramos, M., Sobarzo, M., Pizarro, O., & Valle-Levinson, A. (2013). Barotropic and baroclinic semidiurnal tidal currents in two contrasting coastal upwelling zones of Chile. J. Geophys. Res. Oceans, 118(3), 1226-1238