CEAZA
Zoning of the Mejillones Peninsula marine protected coastal area of multiple uses, northern Chile.
Ulloa, R., Vargas, A., Hudson, C., & Rivadeneira, M.
Marine protected areas of multiple uses (MPA-MU), are an important management tool to protect biodiversity and regulate the use of coastal marine resources. However, robust conservation plans require an explicit consideration of not only biological but also social components, balancing the protection of biodiversity with a sustainable exploitation of marine resources. Here we applied the decision-making algorithm MARXAN to provide a zoning analysis at the Mejillones Peninsula MPA-MU in northern Chile, one of largest MPA's of the Humboldt Current Marine Ecosystem. We set conservation goals for coarse and fine-filter conservation targets that were crossed out against different threats and pressure factors from human activities across the area. We identified a portfolio of sites for conservation, within the Mejillones Peninsula MPA-MU, representing different ecological systems with different levels of human impacts and vulnerability. These results may serve as a foundational guideline for the future administration of the MPA-MU.
Año: 2013
Palabras claves: MPA-MU, MARXAN, conservation plans, marine coastal ecosystems, northern Chile.
Referencia APA: Ulloa, R., Vargas, A., Hudson, C., & Rivadeneira, M. (2013). Zoning of the Mejillones Peninsula marine protected coastal area of multiple uses, northern Chile. Lat. Am. J. Aquat. Res. vol.41 no.3 Valparaíso jul.
Naturalised grapevines collected from arid regions in Northern Chile exhibit a high level of genetic diversity.
Milla-Tapia, A., Gómez, S., Moncada, X., León, P., Ibacache, A., & Rosas, M. et al.
Over 150 grapevine accessions were collected and characterised using 11 Simple Sequence Repeats (SSR) markers, to determine the genetic diversity and to propose a population structuring. SSR diversity was high, with observed heterozygosity (Ho = 0.87) greater than expected heterozygosity (He = 0.70). Three discrete genetic groups were identified, which did not show any association with geographical distribution. Groups 1 (G1) and G3 had a higher level of genetic diversity and also an important level of heterozygosity.
Año: 2013
Palabras claves: Arid regions; genetic structure; germplasm; naturalised grapevines; Vitis.
Referencia APA: Milla-Tapia, A., Gómez, S., Moncada, X., León, P., Ibacache, A., & Rosas, M. et al. (2013). Naturalised grapevines collected from arid regions in Northern Chile exhibit a high level of genetic diversity. Australian Journal Of Grape And Wine Research, 19(2), 299-310.
Evidencing a large body of ice in a rock glacier, Vanoise Massif, Northern French Alps.
Monnier, S., Camerlynck, C., Rejiba, F., Kinnard, C., & Galibert, P.
The Sachette rock glacier is an active rock glacier located between 2660 and 2480 m a.s.l. in the Vanoise Massif, Northern French Alps (45° 29′ N, 6° 52′ E). In order to characterize its status as permafrost feature, shallow ground temperatures were monitored and the surface velocity measured by photogrammetry. The rock glacier exhibits near-surface thermal regimes suggesting permafrost occurrence and also displays significant surface horizontal displacements (0.6–1.3 ± 0.6 m yr–1). In order to investigate its internal structure, a ground-penetrating radar (GPR) survey was performed. Four constant-offset GPR profiles were performed and analyzed to reconstruct the stratigraphy and model the radar wave velocity in two dimensions. Integration of the morphology, the velocity models and the stratigraphy revealed, in the upper half of the rock glacier, the good correspondence between widespread high radar wave velocities (>0.15–0.16 m ns–1) and strongly concave reflector structures. High radar wave velocity (0.165–0.170 m ns–1) is confirmed with the analysis of two punctual common mid-point measurements in areas of exposed shallow pure ice. These evidences point towards the existence of a large buried body of ice in the upper part of the rock glacier. The rock glacier was interpreted to result from the former advance and decay of a glacier onto pre-existing deposits, and from subsequent creep of the whole assemblage. Our study of the Sachette rock glacier thus highlights the rock glacier as a transitional landform involving the incorporation and preservation of glacier ice in permafrost environments with subsequent evolution arising from periglacial processes.
Año: 2013
Palabras claves: Rock glacier; ground-penetrating radar; ice.
Referencia APA: Monnier, S., Camerlynck, C., Rejiba, F., Kinnard, C., & Galibert, P. (2013). Evidencing a large body of ice in a rock glacier, Vanoise Massif, Northern French Alps. Geografiska Annaler: Series A, Physical Geography, 95(2), 109-123.
Late Holocene summer temperatures in the central Andes reconstructed from the sediments of high-elevation Laguna Chepical, Chile (32° S).
de Jong, R., von Gunten, L., Maldonado, A., & Grosjean, M.
High-resolution reconstructions of climate variability that cover the past millennia are necessary to improve the understanding of natural and anthropogenic climate change across the globe. Although numerous records are available for the mid- and high-latitudes of the Northern Hemisphere, global assessments are still compromised by the scarcity of data from the Southern Hemisphere. This is particularly the case for the tropical and subtropical areas. In addition, high elevation sites in the South American Andes may provide insight into the vertical structure of climate change in the mid-troposphere. This study presents a 3000 yr-long austral summer (November to February) temperature reconstruction derived from the 210Pb- and 14C-dated organic sediments of Laguna Chepical (32°16' S, 70°30' W, 3050 m a.s.l.), a high-elevation glacial lake in the subtropical Andes of central Chile. Scanning reflectance spectroscopy in the visible light range provided the spectral index R570/R630, which reflects the clay mineral content in lake sediments. For the calibration period (AD 1901–2006), the R570/R630 data were regressed against monthly meteorological reanalysis data, showing that this proxy was strongly and significantly correlated with mean summer (NDJF) temperatures (R3 yr = −0.63, padj = 0.01). This calibration model was used to make a quantitative temperature reconstruction back to 1000 BC.
The reconstruction (with a model error RMSEPboot of 0.33 °C) shows that the warmest decades of the past 3000 yr occurred during the calibration period. The 19th century (end of the Little Ice Age (LIA)) was cool. The prominent warmth reconstructed for the 18th century, which was also observed in other records from this area, seems systematic for subtropical and southern South America but remains difficult to explain. Except for this warm period, the LIA was generally characterized by cool summers. Back to AD 1400, the results from this study compare remarkably well to low altitude records from the Chilean Central Valley and southern South America. However, the reconstruction from Laguna Chepical does not show a warm Medieval Climate Anomaly during the 12–13th century, which is consistent with records from tropical South America. The Chepical record also indicates substantial cooling prior to 800 BC. This coincides with well-known regional as well as global glacier advances which have been attributed to a grand solar minimum. This study thus provides insight into the climatic drivers and temperature patterns in a region for which currently very few data are available. It also shows that since ca. AD 1400, long-term temperature patterns were generally similar at low and high altitudes in central Chile.
Año: 2013
Palabras claves:
Referencia APA: de Jong, R., von Gunten, L., Maldonado, A., & Grosjean, M. (2013). Late Holocene summer temperatures in the central Andes reconstructed from the sediments of high-elevation Laguna Chepical, Chile (32° S). Climate Of The Past, 9(4), 1921-1932. http://dx.doi.org/10.5194/cp-9-1921-2013
A kinetic approach to saponin extraction during washing of quinoa ( Chenopodium Quinoa Willd.) seeds.
Quispe-Fuentes, I., Vega-Gálvez, A., Miranda, M., Lemus-Mondaca, R., Lozano, M., & Ah-Hen, K.
The aim of this work was to show that the leaching process of saponins from quinoa (Chenopodium quinoa Willd.) seeds during washing with water, as is generally practiced by people in South America, can be modeled using mathematical expressions related to Fick's second law. Experimental data were obtained through batch extraction with a ratio of quinoa to water of 1:10 under constant agitation for processing time between 15 and 120 min at 20, 30, 40, 50 and 60C. It was found that residual saponin concentration in the quinoa seeds decreased as washing temperature increased. Leaching rate followed the Arrhenius relationship, with calculated effective saponin diffusion coefficient between (5.05 ± 0.15) × 10−10 and (32.50 ± 1.65) × 10−10 m2/s as the temperature increased from 20 to 60C. Several mathematical models to describe the kinetic behavior of the leaching process were analyzed. The modified Henderson–Pabis model had the best fit quality as shown by statistical analysis.
Año: 2013
Palabras claves:
Referencia APA: Quispe-Fuentes, I., Vega-Gálvez, A., Miranda, M., Lemus-Mondaca, R., Lozano, M., & Ah-Hen, K. (2013). A kinetic approach to saponin extraction during washing of quinoa ( Chenopodium Quinoa Willd.) seeds. Journal Of Food Process Engineering, 36(2), 202-210.
Seasonal sediment fluxes forcing supraglacial melting on the Wright Lower Glacier, McMurdo Dry Valleys, Antarctica.
MacDonell, S., Fitzsimons, S., & Mölg, T.
Cold-based glaciers exist in low temperature and low humidity environments in which shortwave radiation is the largest source of energy to the glacier surface and the energy budget is very sensitive to the surface albedo. Consequently, the presence of relatively low volumes of debris on glacier surfaces has a significant impact on the timing, magnitude and rate of ablation at the surface. The aim of this study is to understand how the presence of sediment on the glacier surface at the start of the melt season can affect meltwater generation and delivery on a cold-based glacier. A combination of field measurements, energy balance modelling and chemical mixing modelling were used on the Wright Lower Glacier, McMurdo Dry Valleys, Antarctica, between October 2005 and January 2006 to address this aim. In this system, sediment was transported onto the glacier surface during the winter months (March–October) by foehn winds, which reduced surface albedo at the start of the summer melt season. The areas of the glacier on which sediment accumulated began to melt earlier than other parts of the glacier and experienced a longer melt season. Over the study period, the total ablation on the dirty surfaces was nine times greater than for clean ice. Ablation on the dirty surfaces is dominated by melting, whereas sublimation dominates the clean ice. As the sediment was unevenly distributed over the glacier surface, the variation in melt amount and timing drove the development of a cryoconite hole system. Copyright © 2012 John Wiley & Sons, Ltd.
Año: 2013
Palabras claves: Glacier hydrology; cryoconite hole; glacier energy balance; hydrochemistry.
Referencia APA: MacDonell, S., Fitzsimons, S., & Mölg, T. (2013). Seasonal sediment fluxes forcing supraglacial melting on the Wright Lower Glacier, McMurdo Dry Valleys, Antarctica. Hydrol. Process., n/a-n/a.
Trends in Antarctic ecological research in Latin America shown by publications in international journals.
Stotz, G., Salgado-Luarte, C., Rios, R., Acuña-Rodriguez, I., Carrasco-Urra, F., Molina-Montenegro, M., & Gianoli, E.
Antarctica is a highly interesting region for ecologists because of its extreme climatic conditions and the uniqueness of its species. In this article, we describe the trends in Antarctic ecological research participation by Latin American countries. In a survey of articles indexed by the ISI Web of Science, we searched under the categories “Ecology,” “Biodiversity Conservation” and “Evolutionary Biology” and found a total of 254 research articles published by Latin American countries. We classified these articles according to the country of affiliation, kingdom of the study species, level of biological organization and environment. Our main finding is that there is a steady increase in the relative contribution of Latin American countries to Antarctic ecological research. Within each category, we found that marine studies are more common than terrestrial studies. Between the different kingdoms, most studies focus on animals and most studies use a community approach. The leading countries in terms of productivity were Argentina, Chile and Brazil, with Argentina showing the highest rate of increase.
Año: 2013
Palabras claves: Antarctica; Argentina; Brazil; Chile; research trends; scientific productivity.
Referencia APA: Stotz, G., Salgado-Luarte, C., Rios, R., Acuña-Rodriguez, I., Carrasco-Urra, F., Molina-Montenegro, M., & Gianoli, E. (2013). Trends in Antarctic ecological research in Latin America shown by publications in international journals. Polar Research, 32(0).
Can a breakdown in competition-colonization tradeoffs help explain the success of exotic species in the California flora?
Molina-Montenegro, M., Cleland, E., Watts, S., & Broitman, B.
Determining combinations of functional traits that allow a species to colonize new habitats has been central in the development of invasion ecology. Species able to establish in new communities harbor abilities or traits that allow them to use resources or tolerate stress in ways that native species cannot. Tradeoffs among species functional traits along the competition–colonization (CC) continuum, where competitive ability is a decreasing function of dispersal capacity, may allow invasive species to establish themselves in new habitats. The California flora offers a well-characterized model system to examine whether native and exotic species differ in the distribution of functional traits and to examine whether a breakdown of the CC tradeoff is present. We used a random subset of 1000 plants and examined seed traits and life form characteristics along with their seed size and adult height using the Jepson Manual of the plants of California. To test the hypothesis that active dispersal strategies aid in the success of exotic species, we classified species into four seed types according to the presence/absence of mechanisms associated with efficient dispersal. In addition, for each species we compiled data on seed size and adult plant height. We conducted all comparisons between native and exotic species within the four most speciose families to control for potential taxonomic non-independence. Exotic species had smaller seed size but greater plant height than natives of the same families. On the other hand, exotic species also displayed significantly greater proportions of functional traits that enhanced dispersal ability. Additionally, certain sets of functional traits were significantly associated with exotic species, such as annual life histories with small seeds and high dispersal capacity. In the random subset of the California flora examined, exotics of the most speciose plant families show functional trait combinations that appear to violate the tradeoff structures observed in their California counterparts. Our results suggest that taxonomically controlled comparisons of the CC tradeoff structure between natives and exotic species may shed light of the capacity of those exotic species invasive ability to colonize new habitats.
Año: 2012
Palabras claves:
Referencia APA: Molina-Montenegro, M., Cleland, E., Watts, S., & Broitman, B. (2012). Can a breakdown in competition-colonization tradeoffs help explain the success of exotic species in the California flora?. Oikos, 121(3), 389-395.
Characterization of the interactions between subterranean and superficial fluxes within an Andean catchment as a function of the spatio- temporal variability of climate.
Jourde, H., Blanc, M., Rochette, R., Ruelland, D., Hicks, E., & Oyarzun, R
In the semi-arid region of Norte Chico (Chile), climate variability, mainly controlled by ENSO and LNSO events, generates a high variability of both surface water and groundwater fluxes. Taking the upper Elqui catchment as an example, this study found that, during LNSO events, the abnormally high values of the runoff coefficient may be the consequence of a groundwater contribution to surface water flow. During ENSO events, however, the lower values of the runoff coefficient and the dynamics of the water table level highlight the recharge of the subsurface compartment. For the hydrological years characterized by a high pluviometric index during the 1977–2008 period, three dynamics of interaction between groundwater and surface water are identified : (i) the water table increases before the river discharge, and its logarithmic increase highlights a rapid recharge related to the concomitance of snowmelt and rainfall events ; (ii) the water table increases after the river discharge and its exponential increase shows a progressive intensification of the recharge over time ; and (iii) the water table and the river discharge increase are concomitant. Dynamics (i) and (ii) are observed during the ENSO events, when precipitation occurs over a long time period ; dynamic (iii) is observed during the neutral years, when high intensity precipitations occur over short periods. The analysis of these dynamics and runoff coefficients shows that when the mean annual precipitation is less than 70 mm, the relative equilibrium between runoff and recharge processes is broken, which may generate a high hydrological deficit; this threshold could thus be used as a warning for drought. Finally, the spatial variability of runoff coefficients shows a larger contribution of the subsurface compartment in catchment with a larger proportion of granites, suggesting a mountain front recharge from the alterites in the granitic watershed.
Año: 2012
Palabras claves: hydro-climatic variability, water resource, surface, subsurface interactions, snowmelt, Río Elqui, North-Central Chile.
Referencia APA: Jourde, H., Blanc, M., Rochette, R., Ruelland, D., Hicks, E., & Oyarzun, R. (2012). Caractérisation des interactions entre flux souterrains et superficiels dans un bassin andin en fonction de la variabilité spatio-temporelle du climat. La Houille Blanche, (2), 18-25
Activity patterns and predatory behavior of an intertidal nemertean from rocky shores: Prosorhochmus nelsoni (Hoplonemertea) from the Southeast Pacific.
Caplins, S., Penna-Diaz, M., Godoy, E., Valdivia, N., Turbeville, J., & Thiel, M.
Understanding the impact of environmental stressors on predator activity is a prerequisite to understanding the underlying mechanisms shaping community structure. The nemertean Prosorhochmus nelsoni is a common predator in the mid-intertidal zone on rocky shores along the Chilean coast, where it can reach very high abundances (up to 260 ind m−2) in algal turfs, algal crusts, barnacle crusts, and mixed substrata. Tidal and diurnal scans revealed that the activity of P. nelsoni is primarily restricted to night and early-morning low tides and is relatively low when air temperatures are high. On average, larger worms crawled faster than smaller worms, with their maximum velocity being influenced by substratum type. Their estimated rate of predation is 0.092 prey items nemertean−1 day−1, just below the laboratory rate of ~0.2 amphipods nemertean−1 day−1 previously estimated for this species. P. nelsoni consumes a diverse spectrum of prey items (i.e., amphipods, isopods, decapods, barnacles, and dipterans) and is possibly exerting a significant influence on its prey populations. We suggest that the opportunistic predatory behavior of this intertidal predator is caused by the trade-off between immediate persistence (e.g., avoidance of desiccation) and long-term survival through successful foraging.
Año: 2012
Palabras claves:
Referencia APA: Caplins, S., Penna-Diaz, M., Godoy, E., Valdivia, N., Turbeville, J., & Thiel, M. (2012). Activity patterns and predatory behavior of an intertidal nemertean from rocky shores: Prosorhochmus nelsoni (Hoplonemertea) from the Southeast Pacific. Marine Biology, 159(6), 1363-1374.
Latin American plant sciences: from early naturalists to modern science.
Stoll, A. & Squeo, F.
Editorial
Año: 2012
Palabras claves:
Referencia APA: Stoll, A. & Squeo, F. (2012). Latin American plant sciences: from early naturalists to modern science. Plant Ecology & Diversity, 5(2), 147-151.
Climatic trends and impact of climate change on agriculture in an arid Andean valley.
Fiebig-Wittmaack, M., Astudillo, O., Wheaton, E., Wittrock, V., Perez, C., & Ibacache, A.
Little is known about climate change and its impacts for the arid coastal and mountainous regions in northern Chile. The Elqui river basin, part of the Norte Chico of Chile between 27ºS and 33ºS latitude, is located south of the hyper-arid Atacama desert. Despite water scarcity, agricultural development in this region has been enhanced by agronomic practices and the marketing of valuable products. This paper characterizes the actual climate conditions and presents an overview and analyses of past climate variability, and future possible climate trends, emphasizing those relevant to agriculture. Precipitation shows an important decrease during the first decades of the past century. Runoff shows decreasing trends for the first half of the past century and increases for 1960 to 1985. Drought appears to be increasing. Statistical downscaling was accomplished using the Long Ashton Research Station Weather Generator. Both future periods of 2011 to 2030 and 2046–65 showed trends to higher minimum and maximum temperature. The number of hot days (maximum temperature greater than or equal to 30°C) has a strong increasing trend during October to April. Even though the downscaled results for precipitation do not show trends, the continuation of the present trend of low amounts is a concern. We discuss some implications of climatic changes for agriculture and we emphasize the importance of adaptation, especially to deal with water scarcity.
Año: 2012
Palabras claves:
Referencia APA: Fiebig-Wittmaack, M., Astudillo, O., Wheaton, E., Wittrock, V., Perez, C., & Ibacache, A. (2012). Climatic trends and impact of climate change on agriculture in an arid Andean valley. Climatic Change, 111(3-4), 819-833