Search

The demand for mountain water resources is increasing, and their availability is threatened by climate change, emphasizing the urgency for effective protection and management. The upper Sali-Dulce watershed holds vital significance as it contributes the majority of the Sali-Dulce water resources, supporting a densely populated dry region in Northwestern Argentina, covering an area of 24,217 km 2 . However, the potential impact of climate change and land use/land cover change on water yield in this watershed remains uncertain. This study employs the InVEST Annual Water Yield model to analyze the average water yield in the watershed and evaluate its potential changes under future scenarios of climate and land use/land cover change. InVEST was calibrated using data from multiple river gauges located across the watershed, indicating satisfactory performance (R 2  = 0.751, p-value = 0.0054). Precipitation and evapotranspiration were the most important variables explaining water yield in the area, followed by land use. Water yield showed a notable concentration in the montane area with 40% of the watershed accounting for 80% of the water yield, underscoring the importance of conserving natural land cover in this critical zone. Climate change scenarios project an increase in water yield ranging from 21 to 75%, while the effects of land cover change scenarios on water yield vary, with reforestation scenarios leading to reductions of up to 15% and expansions in non-irrigated agriculture resulting in increases of up to 40%. Additionally, water yield distribution may become more concentrated or dispersed, largely dependent on the type of land cover. The combined scenarios highlight the pivotal role of land cover in adapting to climate change. Our findings provide valuable insights for designing future studies and developing policies aimed at implementing effective adaptation strategies to climate change within the Salí-Dulce watershed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study analyzes the weather-related health damage of present and future extreme temperatures in Argentina. Focusing on mortality, short-term impacts of temperature are obtained by regressing monthly mortality rates on inter-annual monthly weather variability. For this purpose, a countrywide panel dataset at the municipal level was constructed from the universe of deaths between 2010 and 2019, and daily meteorological records from the ERA5 weather dataset. Then, NASA Earth Exchange Global Daily Downscaled Projections (NEX-GDDP) are used to project future mortality by 2085 under two climate scenarios. Finally, present and future mortality-related economic damages are assessed using the Value of a Statistical Life. The results show that one additional day of extreme temperatures increase all-cause mortality rates relative to mild weather and that the impact of hotter-than-average temperatures is greater in magnitude than that of colder ones. Substantial heterogeneity exists between causes of death and age groups, with older people facing greater risks, while the results for gender are inconclusive. All days of extreme cold in a year generate damage equivalent to 0.64% of GDP, while heat damage is 0.11% of GDP. The total damage by extreme temperatures adds up to 0.75% of the 2019 GDP. When future temperatures are valued, the total damage increases by an additional 1.45% under scenario RCP8.5 because the lower mortality occurring on cold days only partially offsets the increase in the number of hot days. On the contrary, if temperature changes were to be mild (i.e., under scenario RCP4.5), overall mortality would be lower at the national level and the corresponding damages would decrease by 0.02%., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

This paper evaluates whether exposure to natural disasters very early in the life of a person has persistent effects on her human development outcomes in the case of Argentina. Using the microdata of the 2010 National Census of Population and the Disaster Inventory System's (DesInventar) records of the occurrence of natural disasters, we estimate a differences in differences model, exploiting geographical variation (between districts of Argentina) and temporal variation (between birth cohorts) in the occurrence of natural disasters. Fixed effects are considered by cohorts and districts, as well as control variables. We find that exposure to natural disasters during the first year of life significantly reduces the number of years of schooling achieved in 0.03 years and increases the chances of being unemployed when adult. Importantly, we find that the personal experience of a natural disaster goes beyond individual outcomes, increasing the chances of living in a multidimensionally poor household when adult. Exposure to natural disasters during gestation also has significant detrimental impact on these outcomes. In the context of climate change, in which an increase in the frequency and severity in the occurrence of natural disasters is expected, our results are a call of attention, indicating that it is of outmost importance to design and implement public policies towards increasing the country's preparedness and resilience to natural disasters. [ABSTRACT FROM AUTHOR]

Biodiversity loss remains one of the most pressing issues for global governance. This situation can be seen in Argentina and Chile through the effects of biodiversity loss caused by the introduction and expansion of beavers in Southern Patagonia. This case is interesting because, despite the Beagle conflict (i.e., the border dispute) between these countries some decades ago, nowadays Argentina and Chile are facing shared environmental problems and both are actively seeking solutions. The main question in this paper is, how did Argentina and Chile search for a solution to shared environmental problems caused by the expansion of beavers in Southern Patagonia? This paper tackles this question and presents the results of the conducted qualitative research. The results indicate that, in order to understand what Argentina and Chile are doing to achieve a solution to their shared environmental problems, research cannot be exclusively focus on domestic affairs. Instead, this issue requires taking into account how international dimensions influenced domestic policies. As this paper argues, in Argentina and Chile, international cooperation is a method of influencing biodiversity governance through funds granted by international organizations and international expert recommendations. [ABSTRACT FROM AUTHOR]

During the 20th century, there has been an ongoing agricultural expansion and global warming, two of the main determinants influencing biodiversity changes in Argentina. The red hocicudo mouse (Oxymycterus rufus) inhabits subtropical grasslands and riparian habitats and has increased its abundance in recent years in central Argentina agroecosystems. This paper describes the long‐term temporal changes in O. rufus abundance in Exaltación de la Cruz department, Buenos Aires province, Argentina, in relation to weather fluctuations and landscape features, as well as analyzes the spatio‐temporal structure of captures of animals. We used generalized liner models, semivariograms, the Mantel test, and autocorrelation functions for the analysis of rodent data obtained from trappings conducted between 1984 and 2014. O. rufus showed an increase in abundance across the years of study, with its distribution depending on landscape features, such as habitat types and the distance to floodplains. Capture rates showed a spatio‐temporal aggregation, suggesting expansion from previously occupied sites. O. rufus was more abundant at lower minimum temperatures in summer, higher precipitation in spring and summer, and lower precipitations in winter. Weather conditions affected O. rufus abundance, but there was local variation that differed from global patterns of climate change. [ABSTRACT FROM AUTHOR]

In this paper we review the growing evidence of anthropogenic landscapespresent in the semi-deciduous neotropical forest biomes of eastern NW Argentina,which have remained relatively neglected in favour of arid to semi-arid western Andean regions. The evidence gathered in de El Alto-Ancasti provides animportant case study where multidisciplinary methodologies have beenapplied to sites that document the emergence and variability in food productionstrategies across the eastern Andean forests and grasslands of NWArgentina. We discuss evidence offarming structures from archaeological surveys, plant management from phy-tolith analysis, and the tempo and nature of settlement from archaeological excavations undertaken at a variety of sites in the El Alto Ancasti mountainrange. We suggest that the communities that inhabited this region during thefirst millennium AD (ca. 1500–1000 BP) established a strategy of 'overlappingpatchworks' of food production that were able to contend with considerableseasonal variability. We argue that, through the use of cross-channelling, low river areas, erosion control techniques and the establishment of mesothermal crops,including maize, legumes, and tubers, throughout the region, these societies adopted flexible strategies to adapt to life in a region prone to climatic change [ABSTRACT FROM AUTHOR]

This paper explores how significant are the ecological and climatic variables to influence the stable isotopes of guanacos. Lama guanicoe bone collagen carbon and nitrogen stable isotope ratios are assumed as a macro regional average value in west Argentina, mostly as a baseline to model archaeological human diet. If stable isotopes on mammals reflex ecology and climate, we need to know how those variables influence mammals bone stable isotope ratio. This paper analyses the 13C/12C and 15 N/14N ratio on bone collagen on 122 guanacos from Northwest Patagonia during the Holocene. The results confirm significant variation in both isotopes between Monte and Andean-Patagonian specimens. Guanacos from Monte shows higher δ13C and δ15N than those from Andean-Patagonian. Temporal trends indicate variation through Holocene but this variation is not spatially homogeneous. In this paper we suggest that Medieval Climatic Anomaly had stronger effect in Monte desert than in Patagonia desert, generating driest and/or hottest conditions between 1250 and 600 years BP. Those variations need to be considered to reconstruct human diet at least during the second part of the Holocene. [ABSTRACT FROM AUTHOR]

This paper deals with the hydrological variability effects on the primary commercial fish species inhabiting the main channel and the floodplain of the large Paraná River in its middle reaches in Argentina. Analysing more than eight decades (1935–2016) of information on the most frequent and abundant commercial species in conjunction with hydrological levels and temperature, our results show that spring–summer floods of a certain magnitude (c. 6 m) and durations (> 80 days) are crucial for sustaining commercial fisheries. Moreover, the frequency of these floods was modulated by the decadal climatic fluctuations that have occurred over the past 100 years in the Paraná Basin. An insight into the probable incidence of some anthropogenic influences is also provided. [ABSTRACT FROM AUTHOR]

Copyright of Anales de Derecho is the property of Servicio de Publicaciones de la Universidad de Murcia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of PsyEcology is the property of Sage Publications Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Mosquito-borne diseases (e.g., transmitted by Aedes aegypti) affect almost 700 million people each year and result in the deaths of more than 1 million people annually. Methods: We examined research undertaken during the period 1951–2020 on the effects of temperature and climate change on Ae. aegypti, and also considered research location and between-country collaborations. Results: The frequency of publications on the effects of climate change on Ae. aegypti increased over the period examined, and this topic received more attention than the effects of temperature alone on this species. The USA, UK, Australia, Brazil, and Argentina were the dominant research hubs, while other countries fell behind with respect to number of scientific publications and/or collaborations. The occurrence of Ae. aegypti and number of related dengue cases in the latter are very high, and climate change scenarios predict changes in the range expansion and/or occurrence of this species in these countries. Conclusions: We conclude that some of the countries at risk of expanding Ae. aegypti populations have poor research networks that need to be strengthened. A number of mechanisms can be considered for the improvement of international collaboration, representativity and diversity, such as research networks, internationalization programs, and programs that enhance representativity. These types of collaboration are considered important to expand the relevant knowledge of these countries and for the development of management strategies in response to climate change scenarios. [ABSTRACT FROM AUTHOR]

Many habitat-specialist organisms occur in distinct, patchy habitat, yet do not occupy all patches, and an important question is why apparently suitable habitat remains unoccupied. We examined factors influencing patch occupancy in near-threatened, little-known Diademed Plovers (Phegornis mitchellii), arguably the bird most specialized to life in High Andean peatlands. Andean peatlands are well-suited to occupancy modelling because they are discrete patches of humid habitat within a matrix of high-altitude steppe. We hypothesized that Diademed Plovers occupy preferably larger and more humid peatlands, and avoid peatlands used for grazing by llamas and vicuñas, which may trample vegetation and nests. From December 2021 to February 2022 (breeding season), we conducted plover occupancy surveys (2–4) on 40 peatlands at Lagunas de Vilama, a landscape of arid steppe and wetlands above 4,500 m in NW Argentina. We measured peatland size, grazing pressure, topographic and remotely-sensed variables that correlate with humidity, and incorporated these as covariates in occupancy models. Occupancy models showed that more than 50% of the studied peatlands were used by Diademed Plovers and most showed signs of reproduction, highlighting the importance of the Vilama Wetlands for Diademed Plover conservation. Within peatlands, Diademed Plovers were most often associated with headwaters. The top ranked occupancy model included constant detection, random spatial effects, and a single occupancy covariate: mean NDWI (Normalized Difference Water Index, an index correlated with water content and humidity) over the previous three years. Contrary to our prediction, Diademed Plovers preferred less water-saturated peatlands (lower NDWI), possibly to avoid nest flooding. This may be especially important in wet years, like the year when we conducted our surveys. Neither peatland size nor grazing by llamas and vicuñas affected peatland use by Diademed Plovers, suggesting that llama grazing at current levels may be compatible with plover conservation. For organisms that specialize on humid habitats, such as peatlands, factors affecting occupancy may vary temporally with variation in climate, and we recommend follow-up surveys across multi-year timescales to untangle the impact of climate on animals' use of humid habitats. [ABSTRACT FROM AUTHOR]

Background: Eco-anxiety is increasingly recognized as a shared experience by many people internationally, encompassing fear of environmental catastrophe and anxiety about ecological crises. Despite its importance in the context of the changing climate, measures for this construct are still being developed in languages other than English. Methods: To contribute to global eco-anxiety research, we translated the Hogg Eco-Anxiety Scale (HEAS) into Spanish, creating the HEAS-SP. We validated this measure in samples from both Argentina (n = 990) and Spain (n = 548), performing measurement invariance and confirmatory factor analyses. Internal consistency of the scale and score stability over time were investigated through reliability analyses. Differences in eco-anxiety across sociodemographic variables were explored through Student's t-tests and Pearson's r tests. Results: The four-factor model of the HEAS-SP comprising affective and behavioural symptoms, rumination, and anxiety about personal impact demonstrated excellent model fit. We found good internal consistency for each subscale, and established measurement invariance between Spanish and Argentine samples, as well as across genders and participants' age. Spanish participants reported higher scores on the affective symptoms and personal impact anxiety factors compared to the Argentinian sample. Also, men reported lower levels than women on the subscales of affective symptoms, rumination, and personal impact anxiety. It was found that the relationship between both age and personal impact anxiety and age and affective symptoms varies significantly depending on the gender of the individuals. Younger participants tended to report higher scores on most dimensions of eco-anxiety. Conclusions: These findings enhance the global initiative to investigate, explore and therefore comprehend eco-anxiety by introducing the first valid and reliable Spanish-language version of this psychometric instrument for its use within Spanish and Argentinian populations. This study augments the body of evidence supporting the robust psychometric properties of the HEAS, as demonstrated in prior validations for Australian, Turkish, Portuguese, German, French, and Italian populations. [ABSTRACT FROM AUTHOR]

The paper addresses vulnerability to Global Environmental Change of rural producers of Mendoza River basin, in Argentina. Vulnerability is a complex phenomenon that is generated at the intersection of environmental, social and economic dimensions. From a qualitative study based on in-depth interviews with producers of the study area, the paper explain the processes affecting actors (exposures / sensitivities) and the practices (adaptations) they develop to address these phenomena. The main idea is that hydroclimatological events act on a number of previous, long-term vulnerabilities defined by access to resources. Also it shows that resources are critical to the development of adaptive capacities, but finds that "availability of resources" and "capacity building" are not phenomena always related by a linear and direct causality. That is, sometimes the mere existence of resources is not enough to foster adaptive capacities. Noting some capacities gaps, the article identifies critical factors that could improve rural actors' capacities and could strengthen them to cope with future global climate events and other factors that affect their living conditions. [ABSTRACT FROM AUTHOR]

The annual amount of precipitation inputs received by a site during a full year is considered a dominant spatial and temporal control of primary productivity and other related process in arid to subhumid ecosystems. However, to be effectively used by plants, these inputs have to escape runoff, favoured by large and less frequent precipitation events, and evaporation losses, favoured by small and more frequent events. Thus, available water for plant transpiration is not only influenced by the annual sum of precipitation events but also by their frequency-size distribution. In this paper, we characterize this distribution and its association to total annual precipitation inputs through space (five sites along a tenfold precipitation gradient across 1000 km) and time (1961-2010) in the plains of central Argentina. We decomposed total precipitation into two structural components, which are the frequency and mean size of events, showing that they have similar contributions (log-log slopes ≈ 0·5) explaining precipitation shifts in space. Over time, however, we found a preponderance of mean event size explaining precipitation fluctuations, particularly towards wetter sites (log-log slopes increasing from 0·61 to 0·88). The relative variability of event sizes, independent of their mean size (i.e. inequality), was numerically characterized with Gini coefficients derived from Lorenz curves, which showed highly constant values in space and time. Assuming fixed event-size thresholds for evaporation and runoff, and ignoring other controls beyond precipitation structure, the proportion of water potentially available for plant transpiration grew with total precipitation, raising from 0·45 to 0·71 from the driest to the wettest sites, but displaying stronger responses to total precipitation in time, particularly in drier sites. No long-term trends in any of the precipitation structure variables were detected. Response functions of frequency and mean size of events to annual precipitation together with Lorenz curves appeared to be robust descriptors of precipitation regimes that, not requiring any a priori assumptions, are useful to assess how spatial and temporal shifts in total precipitation may concurrently affect its relative availability for plant transpiration. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In recent decades, multiple flood events have had a devastating impact on soybean production in Argentina. Recent advances suggest that the frequency and intensity of destructive flood events on the Argentinian Pampas will increase under pressure from climate change. This paper provides bottom-up insight into the flood risk for soybean production systems under climate change and the suitability of adaptation strategies in two of the most flood-prone areas of the Pampas region. The flood risk perceptions of soybean producers were explored through interviews, translated into climatic indicators and then studied using a multi-model climate data analysis. Soybean producers perceived the present flood risk for rural accessibility to be of the highest concern, especially during the harvest and sowing seasons when heavy machinery needs to reach soybean lots. An analysis of climatic change projections found a rising trend in annual and harvest precipitation and a slight drying trend during the sowing season. This indicates that the flood risk for harvest accessibility may increase under climate change. Several adaptation strategies were identified that can systemically address flood risks, but these require collaborative action and cannot be undertaken by individual producers. The results suggest that if cooperative adaptation efforts are not made in the short term, the continued increase in flood risk may force soybean producers in the case study locations to shift away from soybean towards more robust land uses. [ABSTRACT FROM AUTHOR]

Soil moisture and meteorological variables are strongly related to each other through different fluxes, constituting a complex network of interactions and feedbacks. Therefore, a better understanding of the temporal and spatial variability of soil moisture and its relationship with meteorological variables acquires a particular interest, especially under climate change conditions. Based on the gap in studies addressing this topic in Argentina, this study aimed to evaluate soil moisture content (SMC) and water deficit (DEF) annual trends between 1990 and 2019 and the contribution of different meteorological variables to those trends. To this end, simulations of SMCand DEF were performed by using a hydrological balance model, driven by meteorological observations of 51 sites distributed throughout Argentina. Since precipitation (PP) and potential evapotranspiration (PE) modulate the simulated soil moisture, annual PP and PE trends were also evaluated to assess the importance of these variables on the observed soil moisture changes. Furthermore, the regional contribution of the meteorological variables to the PE trends was assessed by means of a detrended method. Trends detected in SMC and DEF suggest an increase towards drier conditions in some areas of the country. Changes in PE were the main responsible for changes in SMC and DEF and were more relevant than changes in PP. In sites located in the center and east of the country, maximum and mean temperatures had a greater impact on PE. In sites located in the west of the country, changes in PE were mainly controlled by increases in wind speed and decreases in humidity. Examining the spatio-temporal variability of soil water and the meteorological variables that influence soil water is indispensable to assess climate-induced changes and propose feasible climate change adaptation strategies. [ABSTRACT FROM AUTHOR]

Reference evapotranspiration (ETo) is a variable used to characterize the evaporative demand of the atmosphere and its impact on the water balance. During the last decades, significant ETo variabilities have been observed, especially at mid‐latitudes. These variabilities respond mainly to local variations in their physical drivers, such as solar radiation, vapour pressure deficit or wind speed. In this study, the annual and seasonal ETo estimates are generated using the Penman–Monteith method (FAO). Surface weather stations for the Argentine territory and reanalysis data for southern South America of the last four decades (1981–2020) are used. Contributions of both aerodynamic (ETaero) and radiative (ETrad) effects are evaluated to analyse their driving role. Significant positive ETo trends are observed from reanalysis data throughout Argentina, especially on the central east side of the Andes Mountain range with values up to 10 mm·year−1. Most of these ETo changes respond to positive trends in air temperature in the study area, while those in the central Andes also respond to negative trends in dew point temperatures. On the other hand, the increase in energy availability through positive trends in net surface radiation produced a slightly higher ETo in the northern regions of the country. Regional ETo values have shown to be more sensitive to variations in air temperature in the northeastern areas, although changes in humidity and solar radiation could also play a role. In a context of climate change, given that temperature and rainfall are expected to increase in the central and northeastern region of the country and decrease along the eastern side of the Andes Mountains in the coming decades, the characteristics observed over the 1981–2020 period are expected to intensify in the near future. [ABSTRACT FROM AUTHOR]

Copyright of Cultural Studies of Science Education is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Patagonia features the most extensive glaciers of the Southern Hemisphere, excluding Antarctica, and a vast inventory of glacial landforms, so it is thought to have played a key role in (paleo)glacier studies since the late 19th century. However, no systematic attempts to characterize the specific research trends and the scientific community focused on Patagonian cryosphere have been conducted so far. To fill this gap, we analyzed the metadata associated to 305 articles compiled from the Web of Science database following a bibliometric approach covering the period between 1976 and 2020. Our results point to an irregular but net increase on the number of contributions on Patagonian (paleo)glaciers. Mass balance analyses based on satellite data of present-day glaciers and the reconstruction of past glacier activity by dating glacial landforms formed during the Last Glacial Termination, were the most addressed topics during the analyzed period. Patagonian (paleo)glacier studies are mostly published in generic Earth Sciences publications, followed by Quaternary and glaciological journals. Most of the studies were led by scientists from the United Kingdom, followed by Chile, Argentina and United States. In terms of collaborations, these studies can be divided into two main clusters, one composed by researchers from United States, Chile and Argentina institutions, and another mostly composed by British researchers. So far, the most prolific authors are nearly equally distributed in nationality, yet gender inclusion and international collaborations are still caveats that must be solved. Even though our query on the Web of Science missed highly influential (so-called) grey literature, such as local scientific journals and technical reports, the reviewed scientific literature unambiguously indicates that Patagonia is a privileged location for (paleo)glaciers studies worldwide and that it will continue offering vast opportunities to tackle critical questions related to global cryosphere and past-to-present climate changes. • Patagonia is a privilege site for studying present and past glacier dynamics and the evolution of climate changes at hemispheric and global scale. • Glacier dynamics during the 20th century and and the Last Glacial Termination are the most common topics addressed in past decades in the WOS. • Patagonian (paleo)glacier studies has contributed to the development or improvement of diverse analytical techniques. • United Kingdom, United States, Chile and Argentina produced the largest number of WOS-listed papers on (paleo)glaciers in past decades. • The related scientific community is fairly heterogeneous. Although, inclusion and international collaboration issues still need to improve. [ABSTRACT FROM AUTHOR]

Mitigating climate change requires a global transition from fossil fuels to a "green economy" driven by renewable energies. This shift has fostered massive investments in mining resources, notably lithium in South America, needed to store renewable energies. These mining ventures often produce harmful externalities where lithium is located. In Argentina, a major producer, striking variation has occurred in the fortunes of lithium-mining projects. In some instances, mining companies offered concessions that mitigated environmental damage and improved local socioeconomic conditions. In others, companies made minimal concessions, and in a third set they halted projects in response to local resistance. Why do mining ventures result alternatively in negotiated, unnegotiated, or aborted extraction? The article proposes a new typology of modes of extraction together with a multilevel explanatory framework that centers on the strengths and strategies of transnational mining companies, subnational governments, and local communities in setting the terms for extracting lithium. [ABSTRACT FROM AUTHOR]

The precise environmental mechanisms controlling Quaternary glacial cycles remain ambiguous. To address this problem, it is critical to better comprehend the drivers of spatio-temporal variability in ice-sheet evolution by establishing reliable chronologies of former outlet-glacier advances. When spanning multiple glacial cycles, such chronologies have the capacity to contribute to knowledge on the topic of interhemispheric phasing of glaciations and climate events. In southern Argentina, reconstructions of this kind are achievable, as Quaternary expansions of the Patagonian Ice Sheet have emplaced a well-preserved geomorphological record covering several glacial cycles. Moreover, robust ice-sheet reconstructions from Patagonia are powerful barometers of former climate change, as Patagonian glaciers are influenced by the Southern Westerly Winds and the Antarctic Circumpolar Current coupled to them. It is essential to better constrain former shifts in these circulation mechanisms as they may have played a critical role in pacing regional and possibly global Quaternary climate change. Here, we present a new set of cosmogenic 10 Be and 26 Al exposure ages from pre-Last Glacial Cycle moraine boulder, glaciofluvial outwash cobble, and bedrock samples. This dataset constitutes the first direct chronology dating pre-Last Glacial Maximum (LGM) glacier advances in northern Patagonia and completes our effort to date the entire preserved moraine record of the Río Corcovado valley system (43 ∘ S, 71 ∘ W). We find that the outermost margins of the study site depict at least three distinct pre-Last Glacial Cycle stadials occurring around 290–270, 270–245, and 130–150 ka. Combined with the local LGM chronology, we discover that a minimum of four distinct Pleistocene stadials occurred during Marine Isotope Stages 8, 6, and 2 in northern Patagonia. Evidence for Marine Isotope Stage 4 and 3 deposits were not found at the study site. This may illustrate former longitudinal and latitudinal asynchronies in the Patagonian Ice Sheet mass balance during these Marine Isotope Stages. We find that the most extensive middle-to-late Pleistocene expansions of the Patagonian Ice Sheet appear to be out of phase with local summer insolation intensity but synchronous with orbitally controlled periods of longer and colder winters. Our findings thus enable the exploration of the potential roles of seasonality and seasonal duration in driving the southern mid-latitude ice-sheet mass balance, and they facilitate novel glacio-geomorphological interpretations for the study region. They also provide empirical constraints on former ice-sheet extent and dynamics that are essential for calibrating numerical ice-sheet and glacial isostatic adjustment models. [ABSTRACT FROM AUTHOR]

Favorable climate and soils for rainfed crop production, together with a relatively low population density, results in 70–90% of Argentina grain production being exported. No assessment to date has tried to estimate the potential for extra grain production for soybean, wheat and maize, which account for 78% of total harvested area, by yield gap closure on existing cropland area and its impact at a global scale. The objectives of this paper are (i) to estimate how much additional grain could be produced without expanding crop area by closing yield gaps in Argentina, (ii) to investigate how this production and yield gaps varies across regions and years, and (iii) to analyze how these inter-annual variations are related to El Niño—Southern Oscillation phenomenon (ENSO). Production increase on existing crop area was assessed for soybean, wheat and maize by quantifying the yield gap (Yg), that is, the difference between water-limited yield potential (Yw) and actual yield (Ya). A bottom-up approach was followed to estimate Yw and Yg, in which these parameters were first estimated for specific locations in major crop producing areas and subsequently up-scaled to country level based on spatial distribution of crop area and climate zones. Locally-calibrated crop simulation models were used to estimate Yw at each selected location based on long-term weather data and dominant soil types and management practices. For the analyzed period, the national level Yg represented 41% of Yw for both wheat and maize and 32% of the Yw for soybean. If farmers had closed Yg from these levels to 20% of Yw, Argentina could have increased soybean, wheat and maize production by a respective 7.4, 5.2, and 9.2 Mt, without expanding cropland area. This additional production would have represented an increase of 9%, 4%, and 9% of soybean, wheat, and maize global exports. This potential grain surplus was, however, highly variable because of the ENSO phenomenon: attainable soybean production was 12 Mt higher in favorable “El Niño” years compared with unfavorable “La Niña” years. Interestingly, Yg tended to be higher in wet years, suggesting that farmers do not take full advantage of years with favorable conditions for rainfed crop production. Regional variation in Yg was found in Argentina highlighting the usefulness of this work as a framework to target research and, ultimately, reduce gaps in areas where current yields are well below their potential. [ABSTRACT FROM AUTHOR]

This paper presents the first study of nonmarine ostracods recovered from the Danian of the upper Yacoraite Formation (Balbuena IV sequence) Salta Basin. Six species were identified: Ilyocypris triebeli , Ilyocypris argentiniensis , Neuquenocypris (Alleniella)? sp. 1; Neuquenocypris (Alleniella)? sp. 2; Penthesilenula sp. and four indeterminate species. The ostracod fauna shows fluctuations in abundance, diversity, and preservation associated with different phases of the paleolake evolution. This distribution, clearly delineated by the depositional facies, corroborates previous geochemical analyses and high-resolution sequence stratigraphy developed for the section. In general, the most abundant occurrences of ostracods coincide with high-frequency transgressive tracts of the lake system, which form long-term wettest interval of the upper Yacoraite Formation. • First study with ostracods for the Balbuena IV sequence of the Yacoraite Formation, Salta Basin, Argentina. • Six nonmarine ostracods species are identified. • Temporal distribution of ostracods is in agreement with U/Pb radiometric dating. • Ostracod abundance is correlated with the climatic fluctuations of the dry and wet periods of the paleolake. [ABSTRACT FROM AUTHOR]

The objective of the present paper is to recognize and reconstruct, from the analysis of pollen recovered from sedimentary cores, the predominant plant communities and their variations during the Holocene in Corrientes Argentina, in order to infer changes in climatic conditions, vegetation and paleoenvironmental evolution in the northeast of Argentina. For this study, lakes located in the central region of Corrientes province were selected, comprising part of the western margin of the Iberá Wetland. The palynological analysis of the paleocommunities shows, in a first stage of the mid Holocene, the predominance of marsh grasslands and hygrophilous communities that indicates humid to sub‐humid environmental conditions. In a later stage of the mid Holocene, the paleocommunities show a characteristic association of wetlands, which together with the presence of Typha sp., would indicate sub‐humid to humid conditions and waterlogged or flooded soils with slow‐moving water. For the late Holocene, the paleocommunities show, initially, the presence of a grass‐dominated herbaceous steppe, indicating environmental disturbances, which in the fossil record could reflect the combination of intense wind action under a dry climate. In a later stage, the frequency and variety of species characteristic of humid environments increase, dominated by marshy‐herbaceous species, in addition to the development of the hygrophilous forest. Consequently, since the mid Holocene, the main climate factors responsible for the observed changes in wetland conditions were the location and intensity of the Atlantic and Pacific anticyclones in addition to changes in sea level. These forces mainly affected the distribution of precipitation, causing significant changes in the vegetation communities. [ABSTRACT FROM AUTHOR]

Copyright of Ecologia Austral is the property of Asociacion Argentina de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The lithium extractive industry is expanding, as technological and economic shifts associated with climate change mitigation goals drive global demand for lithium-ion batteries. This article explores the case of the 'Lithium Triangle', a region of Latin America (spanning Bolivia, Chile and Argentina) that contains the world's largest reserves, and where environmental conflicts associated with lithium mining have proliferated. Emphasising the centrality of discourse in resource governance, we analyse the discursive strategies employed by institutional actors seeking to promote and render acceptable lithium extraction in the region. We argue that such strategies reproduce imaginaries of prosperity and modernisation long attached to oil and mineral wealth, while at the same time introducing a novel association of mining with high-tech industries, 'green jobs' and 'climate-friendly' extraction, seeking to obscure the social and ecological costs of lithium production. This inaugurates an era of 'green extractivism', whereby intensive resource exploitation is framed not only as compatible with climate change, but indeed as necessary to its mitigation. Our findings contribute to ongoing conversations regarding post-fossil fuel 'transitions', by highlighting the contradictory character of mitigation strategies that rely on mineral-intensive development. [ABSTRACT FROM AUTHOR]

Climatic change effects and the processes of urban growth caused environmental deterioration in the city of Buenos Aires. This situation alters the natural hydrological cycle and the hydrograph of floodwaters in urbanizing watersheds will modify, presenting flows higher peak and shorter rise times as it progresses. On the other hand, the global warming has caused an increase in mean annual precipitation and extreme values generated by storms of connective type, in the central region and North of Argentina. One of the possibilities to mitigate these effects is the implementation of extensive green roofs systems in terraces of buildings and houses built that help to reduce runoff factor. The objective of this paper was: to determine the reduction of surface runoff and water quality delivered for different types of green roofs with different types of vegetation implanted in normal rainfall in the city of Buenos Aires. The results of the study that was carried out along one year, showed that the retention capacity of the tested lots varied, depending upon precipitation, type of vegetation and coverage. For the range of 21 and 41 mm the retention ratesreached between 63% and 68%, with rainfall between 42 and 60 mm are observed percentages of retention from 31% to 39%. For the range of 61 to 80 mm the retention percentage was similarly to the range previously analyzed, 25% to 38%, and finally analyzing rainfall greater than 90 mm, the percentage of retention varies between 16% and 22%. The Aptenia cordifolia presented minors values of retention in all ranges except the first. The results of the test showed that green roofs system represent a good alternative in the integrated management of water runoff in urban watersheds. [ABSTRACT FROM AUTHOR]

Background and Aims The acquisitive–conservative axis of plant ecological strategies results in a pattern of leaf trait covariation that captures the balance between leaf construction costs and plant growth potential. Studies evaluating trait covariation within species are scarcer, and have mostly dealt with variation in response to environmental gradients. Little work has been published on intraspecific patterns of leaf trait covariation in the absence of strong environmental variation. Methods We analysed covariation of four leaf functional traits [specific leaf area (SLA) leaf dry matter content (LDMC), force to tear (Ft) and leaf nitrogen content (Nm)] in six Poaceae and four Fabaceae species common in the dry Chaco forest of Central Argentina, growing in the field and in a common garden. We compared intraspecific covariation patterns (slopes, correlation and effect size) of leaf functional traits with global interspecific covariation patterns. Additionally, we checked for possible climatic and edaphic factors that could affect the intraspecific covariation pattern. Key Results We found negative correlations for the LDMC–SLA, Ft–SLA, LDMC–Nm and Ft–Nm trait pairs. This intraspecific covariation pattern found both in the field and in the common garden and not explained by climatic or edaphic variation in the field follows the expected acquisitive–conservative axis. At the same time, we found quantitative differences in slopes among different species, and between these intraspecific patterns and the interspecific ones. Many of these differences seem to be idiosyncratic, but some appear consistent among species (e.g. all the intraspecific LDMC–SLA and LDMC–Nm slopes tend to be shallower than the global pattern). Conclusions Our study indicates that the acquisitive–conservative leaf functional trait covariation pattern occurs at the intraspecific level even in the absence of relevant environmental variation in the field. This suggests a high degree of variation–covariation in leaf functional traits not driven by environmental variables. [ABSTRACT FROM AUTHOR]

Introduction: Cold-adapted bumblebees are vulnerable to climate change (CC). South American Bombus dahlbomii, the southernmost bumblebee worldwide, has strongly declined since the 1990s and may be particularly susceptible to current and future CC. Aims/methods: We asked (1) whether current CC had a role in the observed decline of this species and (2) how projected CC would affect the future distribution of B. dahlbomii. We used a comprehensive record of occurrences for B. dahlbomii and species distribution models (SDMs) to build maps of (1) predicted current climatic suitability using pre-1990s and post-1990s occurrences, and (2) projected current and future climatic suitability under future (2080–2100) RCP 8.5 scenarios predicted by the 5th IPCC Report. Results and discussion: SDMs did not show changes in species climatic suitability pre-1990 vs. post-1990, suggesting no significant role of CC on the observed decline of the species at this time scale. However, a moderate range reduction of 13% and 14% of the ~ 0.041º grid cells was predicted by 2080–2100 under the 70% and 100% consensus models, respectively. Implications for insect conservation: Identifying the threats to B. dahlbomii allows for prioritizing conservation efforts. Short-term threats imposed by invasive bumblebees deserve urgent attention. The potential synergies between this threat and CC need to be understood to better predict the fate of this species. Binational cooperation should guarantee connectivity between climatically suitable areas in Argentina and Chile. [ABSTRACT FROM AUTHOR]

We report gymnospermous wood found in sandstone and siltstone beds of the Upper Triassic Hilario Formation, Sorocayense Group at Hilario Creek located in San Juan province, Argentina. The identified xylotaphoflora comprises Baieroxylon cicatricum (Ginkgoales) and a new species of Protophyllocladoxylon (Coniferales), it constitutes the first reports of these taxa from the Triassic in Argentina. Protophyllocladoxylon hilarioense sp. nov. differs from the other species by the following combination of anatomical characters: radial pits araucarian, mixed and some with abietinian tendency, uni-biseriate; contiguous, separated; tangential pits uni-biseriate; cross-field pits are simple elliptic, oblique, one to two in number and low uni-biseriate rays. The growth rings in the reported woods show a gradual transition from earlywood to latewood, suggesting little change in the climatic conditions experienced during their growth. The type of growth rings observed is consistent with a humid but seasonally dry subtropical climate. These woods are representatives of the arboreal stratum of a mesophytic association [ABSTRACT FROM AUTHOR]

In most nations across the world, the fundamental goal of economic policy is to achieve sustainable economic growth. Economic development, on the other hand, may have an influence on climate change and global warming, which are major worldwide concerns and problems. Thus, this research offers a new perceptive on the influence of renewable and nonrenewable energy consumption on CO2 emissions in Argentina utilizing data from the period between 1965 and 2019. The current research applied the wavelet tools to assess these interconnections. The outcomes of these analyses reveal that the association between the series evolves over both frequency and time. The current analysis uncovers notable wavelet coherence and significant lead and lag connections in the frequency domain, while in the time domain, contradictory correlations are indicated among the variables of interest. From an economic perspective, the outcomes of the wavelet analysis affirm that in the medium and long term, renewable energy consumption contributes to environmental sustainability. Furthermore, in the medium term, trade openness mitigates CO2, although in the long term, no significant connection was found. Moreover, both nonrenewable energy and economic growth contribute to environmental degradation in the short and long term. Finally, the frequency domain causality outcomes reveal that in the long term, economic growth, trade openness, and nonrenewable energy can predict CO2 emissions. The present analysis offers an innovative insight into the interconnection and comovement between CO2 and trade openness, renewable energy utilization, and GDP in the Argentinean economy. The findings from this research should be of interest to economists, researchers, and policymakers. [ABSTRACT FROM AUTHOR]

Biodiversity loss due to climate change is one of the most critical current environmental problems. Global warming is causing substantial species-range shifts and local extirpations, especially for species with restricted distribution ranges. Studies of impact of the climate change on species ranges and environmental suitability have become a fundamental tool for evaluating conservation strategies. However, one important limitation of these approaches is that only species with an adequate number of spatially distinct occurrence records can be modelled, generally excluding threatened rare species from the analyses, a situation referred to as the 'rare species modelling paradox'. To overcome this limitation, we analysed the effect of climate change on the richness of threatened endemic plants of Argentina employing a macroecological modelling approach, using three different modelling techniques (generalized linear mixed models – GLMM, generalized additive models – GAM, and boosted regression trees – BRT), four general circulation models, two representative CO2 concentration pathways (RCPs), and two time periods (2050 and 2070). We identified grid cells with the greatest decline in numbers of threatened endemics, determined species composition in these cells and characterized their vulnerability using three indices. A loss of species richness is observed in ca 83% of the cells, and both protected areas and hotspots of threatened species show significant decrease in future species richness. We identified 32 most affected cells under future climatic projections, including a total of 370 threatened endemic species and exhibiting high beta diversity values (high dissimilarity) among most of the cells. Cells with the highest vulnerability were located along the Central Andes of northwestern Argentina, along the Southern Andean Yungas, High Monte and Central Andean Puna ecoregions, and including a total of 118 threatened endemics (15% of those registered for Argentina) with greater representation of Asteraceae, Apocynaceae, Cactaceae and Iridaceae. However, coverage of protected area network is less than 5% for each of these cells. Our results highlight the urgent need for both in situ and ex situ conservation policies and strategies for the vascular flora of Argentina. [ABSTRACT FROM AUTHOR]

The environmental crisis and more recently climate emergency have driven news media outlets to create editorial brands that specifically cover these topics. To make itself heard in a market for environmental news that is increasingly dominated by global media outlets, La Nación (Argentina) has leveraged its reporting on the topic by developing a novel editorial brand focused on environmental data journalism: "Proyecto Naturaleza." Through the lens of data journalism and collaborative journalism, this article relies on methods such as participant observation and in-depth interviews to understand the practices, norms, and routines adopted by La Nación to produce data journalism focused on environmental topics. The results indicate three specific pillars for such journalism: climate change, biodiversity, and audience participation. The team sets an agenda based on these topics in light of annual events or large celebrations, resulting in a calendar of proposed activities (the production of data stories or crowdsourcing actions). The data team holds meetings with different individuals and organizations from different sectors to identify distinct perspectives on environmental issues to discuss undertakings and collaborate as needed with these actors. La Nación also emphasizes involving audiences on a deeper level, transforming their traditional role as passive recipient into active participant. [ABSTRACT FROM AUTHOR]

High glacial mountain environments around the world are important water reservoirs and are extremely sensitive to the effects of climate change. Considering that climate change affects snow accumulation and glacial melting, it is essential to understand the runoff generation and hydrological dynamics in these type of systems. Andean glaciers have shown a retreating and thinning pattern since the start of the 21st century. Regarding this, the stable isotopic composition of waters is useful to assess the contributions from different sources (i.e., glaciers, precipitation, and tributaries' inputs) to rivers. Several Patagonian mountain rivers have Andean glaciers in their headwaters, one of which is the Manso River. In this basin, over the last 30 years, the Ventisquero Negro Glacier (Manso Glacier's regenerated tongue) experienced a rapid thinning and recession that generated a proglacial lake, called Manso proglacial Lake. In this study, topographic effects upon the stable isotopic composition of river waters (δ2H and δ18O) are recognized, particularly, the altitude effect. The stable isotope composition of the Manso River varies downstream, evolving to a composition more enriched in heavy isotopes in the lower basin, likely due to altitude effects and the progressive evaporation that mainly occurs in the lakes' surfaces that the river crosses. Results show that glacial meltwater is the major water contributor in the upper basin during early fall. In the rest of the basin the stable isotopic composition of the Manso River is mainly controlled by the lakes' isotopic signatures and is highly influenced by two tributary rivers. The concordance between isotopic models and hydrological data demonstrates that stable isotopes constitute a valuable tool to quantify the contribution of different water sources. This has the potential to be particularly useful in areas where discharge data is unavailable. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mountain ecosystems are characterized by steep environmental gradients. Species with broad elevation distribution are exposed to contrasting climatic conditions along their gradients. In response to those changes, species might develop ecotypes adapted to the local climate. Early regeneration is the most critical stage for plant populations and, therefore, withstands strong selection pressures. Previous studies showed a unimodal pattern of intraspecific variability in fitness components among Polylepis australis populations along their elevation gradient in the mountains of central Argentina. Whether this variability is the result of local populations' adjustments to their respective site remains unknown. We tested the hypothesis that P. australis populations from different elevations would be locally adapted to their local environments, where they would perform better than populations from other elevations (origins). We applied an experimental approach by establishing common gardens at three contrasting elevations. Seeds and saplings of P. australis populations from the low, mid- and high elevation belts of the species distribution gradient (i.e. three origins) were reciprocally sown and transplanted in three elevation sites (low, mid- and high). Seed germination success, sapling growth and mortality were monitored for three years. Our main results show that the origin of populations influenced germination success and sapling growth, whereas sapling mortality was marginally affected. Populations of both elevation extremes seem to be more adjusted to local conditions than the population from the intermediate elevation, probably due to the harsher environmental conditions for plant regeneration typical of the lower and upper elevation belts of semiarid mountains. Finally, our results strongly suggest that temperature rise due to climate change in this mountain area might have negative effects on the regeneration of P. australis populations. [ABSTRACT FROM AUTHOR]

Central Argentina from the Pampean flat‐slab segment to northern Patagonia (27°–41°S) represents a classic example of a broken retroarc basin with strong tectonic and climatic control on fluvial sediment transport. Combined with previous research focused on coastal sediments, this actualistic provenance study uses framework petrography and heavy‐mineral data to trace multistep dispersal of volcaniclastic detritus first eastwards across central Argentina for up to ca. 1,500 km and next northwards for another 760 km along the Atlantic coast. Although detritus generated in the Andes is largely derived from mesosilicic volcanic rocks of the cordillera, its compositional signatures reflect different tectono‐stratigraphic levels of the orogen uplifted along strike in response to varying subduction geometry as well as different character and crystallization condition of arc magmas through time and space. River sand, thus, changes from feldspatho‐litho‐quartzose or litho‐feldspatho‐quartzose in the north, where sedimentary detritus is more common, to mostly quartzo‐feldspatho‐lithic in the centre and to feldspatho‐lithic in the south, where volcanic detritus is dominant. The transparent‐heavy‐mineral suite changes markedly from amphibole ≫ clinopyroxene > orthopyroxene in the north, to amphibole ≈ clinopyroxene ≈ orthopyroxene in the centre and to orthopyroxene ≥ clinopyroxene ≫ amphibole in the south. In the presently dry climate, fluvial discharge is drastically reduced to the point that even the Desaguadero trunk river has become endorheic and orogenic detritus is dumped in the retroarc basin, reworked by winds and temporarily accumulated in dune fields. During the Quaternary, instead, much larger amounts of water were released by melting of the Cordilleran ice sheet or during pluvial events. The sediment‐laden waters of the Desaguadero and Colorado rivers then rushed from the tract of the Andes with greatest topographic and structural elevation, fostering alluvial fans inland and flowing in much larger valleys than today towards the Atlantic Ocean. Sand and gravel supply to the coast was high enough not only to promote rapid progradation of large deltaic lobes but also to feed a cell of littoral sediment transport extending as far north as the Río de la Plata estuary. [ABSTRACT FROM AUTHOR]

We describe new remains of notoungulates from the Cerro Azul Formation (late Miocene) in La Pampa Province and reassign others previously studied, helping to precise the taxonomic diversity of 25 fossiliferous localities of this formation. Geomorphological context previously described for the area provides data to place some localities in a temporal sequence. The following Notoungulata are recognised: Protypotherium minutum (Interatheriidae), Paedotherium minor, Tremacyllus impressus, Hemihegetotherium achataleptum, H. torresi, and Hemihegetotherium sp. (Hegetotheriidae), Typotheriopsis silveyrai, T. chasicoensis, and Pseudotypotherium subinsigne (Mesotheriidae), and Pisanodon nazari, Hemixotodon chasicoensis, and cf. Stenotephanos plicidens (Toxodontidae). This study allows adding new localities to the biochronological sequence previously proposed based on the evolutionary pattern of the octodontoid rodents. Chasicoan and early Huayquerian (as herein considered) faunal assemblages present higher diversity of notoungulates than those assigned to late Huayquerian. Some localities lack a representation of taxa significant enough to precise their biochronological position within the late Miocene. The difference in the notoungulates representation along the Chasicoan–Huayquerian ages may be due to climatic changes that affected the centre of Argentina from late Miocene to early Pliocene. [ABSTRACT FROM AUTHOR]

Copyright of Ciência & Trópico (03042685) is the property of Fundacao Joaquim Nabuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spatially resolved estimates of change in soil organic carbon (SOC) stocks are necessary for supporting national and international policies aimed at achieving land degradation neutrality and climate change mitigation. In this work we report on the development, implementation and application of a data‐driven, statistical method for mapping SOC stocks in space and time, using Argentina as a pilot. We used quantile regression forest machine learning to predict annual SOC stock at 0–30 cm depth at 250 m resolution for Argentina between 1982 and 2017. The model was calibrated using over 5,000 SOC stock values from the 36‐year time period and 35 environmental covariates. We preprocessed normalized difference vegetation index (NDVI) dynamic covariates using a temporal low‐pass filter to allow the SOC stock for a given year to depend on the NDVI of the current as well as preceding years. Predictions had modest temporal variation, with an average decrease for the entire country from 2.55 to 2.48 kg C m−2 over the 36‐year period (equivalent to a decline of 211 Gg C, 3.0% of the total 0–30 cm SOC stock in Argentina). The Pampa region had a larger estimated SOC stock decrease from 4.62 to 4.34 kg C m−2 (5.9%) during the same period. For the 2001–2015 period, predicted temporal variation was seven‐fold larger than that obtained using the Tier 1 approach of the Intergovernmental Panel on Climate Change and United Nations Convention to Combat Desertification. Prediction uncertainties turned out to be substantial, mainly due to the limited number and poor spatial and temporal distribution of the calibration data, and the limited explanatory power of the covariates. Cross‐validation confirmed that SOC stock prediction accuracy was limited, with a mean error of 0.03 kg C m−2 and a root mean squared error of 2.04 kg C m−2. In spite of the large uncertainties, this work showed that machine learning methods can be used for space–time SOC mapping and may yield valuable information to land managers and policymakers, provided that SOC observation density in space and time is sufficiently large. Highlights: We tested the use of machine learning for space–time mapping of soil organic carbon (SOC) stock.Predictions for Argentina from 1982 to 2017 showed a 3% decrease of the topsoil SOC stock over time.The machine learning model predicted a greater temporal variation than the IPCC Tier 1 approach.Accurate machine learning SOC stock prediction requires dense soil sampling in space and time. [ABSTRACT FROM AUTHOR]

The interaction of tectonics and climate is considered the main determining factor in the development of different depositional systems (from aeolian to alluvial to lacustrine environments) in intermontane basins. The role of these allogenic controls forces the paleoenvironmental evolution of intermontane basins. In this work, we analyse a Miocene (15–11.5 Ma) synorogenic and volcaniclastic succession of an intermontane basin of the Northpatagonian Andean foreland region. The evolution of the infill was synchronously developed with the Andean uplift and, consequently, with the rain shadow effect generation. A detailed sedimentological and stratigraphic analysis allowed to define eight facies associations, which are lateral and vertical stacked into three different depositional systems. Alluvial depositional systems occurred between 15 and 14.6 Ma, deltaic–lacustrine systems took place between 14.6 and 12.75 Ma, and a reinstatement of alluvial depositional systems occurred between 12.75 and 11.5 Ma. These variations in the depositional systems were contrasted with synchronous tectonic and climatic changes and some considerations about the role of these allogenic controls were discussed to unravel their influence on the paleoenvironmental evolution. The onset of the deltaic–lacustrine depositional system was related to a tectonic reconfiguration whereas the reinstatement of the alluvial depositional system was associated with a regional aridization. Additionally, since the composition of the succession is mainly volcaniclastic, the explosive volcanism is considered and discussed as an extra allogenic control on the evolution of the basin. [ABSTRACT FROM AUTHOR]

1. Because of global climate change and its consequences, estimating the physiological responses of ectothermicorganisms to temperature is of high priority. The thermal increase and changes in fire frequency are some of the consequences of global warming, which could challenge the physiological performance and thermal tolerance of individuals. 2. The present study estimates the thermal parameters from field individuals of the tarantula Grammostola vachoni. To achieve this, we determined the critical thermal limits for locomotor performance, the thermal optimum, and the preferred temperatures. We also calculate the thermal performance breadth and thermal tolerance zone. 3. Temperature strongly affected the locomotor performance of spiders; the sprint speeds were significantly different between temperatures, and at 5 °C and 25 °C the parameter was significantly different between females and juveniles. The preferred temperature showed a mean value of 26.5 °C, and females preferred lower temperature than juveniles. Grammostola vachoni showed a wide thermal tolerance range (close to 43 °C) and thermal performance breadth (B80), an index defined as the range of temperatures at which performance is at least 80% of the maximum. 4. For G. vachoni, these large breadths in the sprint speed represent a substantial buffer against future increases in habitat temperature and shows that the locomotor performance of this species is an adaptable parameter. Understanding the impact of warming in performances is important to make predictions about if this species can remain ecologically viable while facing global change, given the massive worldwide declines in arthropod populations. [ABSTRACT FROM AUTHOR]

The apparently regular and favourable climate that characterizes the Holocene as an interglacial period shows, however, important climatic instability well documented in the Northern Hemisphere. These fluctuations from colder to warmer or wetter to drier affected both biodiversity and human societies in the last 12,000 years, although the impact in Southern America is still poorly known. We are here investigating the biodiversity of small mammal faunas, more sensitive to climatic changes than large mammals, combining taphonomic and palaeoecological data in the Argentine Pampas to better understand the global nature and effect of these Holocene climatic fluctuations. This paper is pioneering applying in this region palaeoecological methodologies practised in European sites, such as the chorotype classification and biomes overlap analyses. The Pampean Region is an ecotone with a confluence of three climatic regions where any change in climatic conditions should be easily detected. Our results, based on the palaeoecological requirements of small mammals, do not indicate severe changes, and most of the sites show climatic stability except for one of them, in which a possible trend towards present conditions (temperate/humid) can be inferred. • New palaeoecological methodologies are applied to the Pampean Region. • Microfauna is the best climatic indicator if multiproxy interpretations are considered. • Cave vs. open-air sites influence the composition of fossil small mammal assemblages. • Human activities in the past can distort palaeoecological interpretations. • Noticeable climatic events in the Northern hemisphere are soften/absent in the South. [ABSTRACT FROM AUTHOR]

The Araucaria Mixed Forests (AMF) are subtropical conifer-hardwood mixed forests that are part of the Atlantic forest floristic dominion in Brazil and Argentina. The AMF is dominated by the conifer Araucaria angustifolia (hereafter araucaria), accompanied by a diversity of angiosperms. Its distribution largely corresponds to the 13°C isotherm and is associated with overall lower temperature, frost-prone, and wetter climates than neighboring vegetation types. Palynological research and bioclimatic modelling have yielded somewhat conflicting results but suggest intense forest-grassland dynamics, with grasslands possibly dominating the landscape during the drier and colder last glacial maximum. Araucaria is a cultural keystone species whose distribution has been greatly fostered by Amerindian activity in the last few millennia. Angiosperms form a lower layer beneath araucaria canopies, and they seem to be geographically structured into a wetter and colder eastern and a drier and hotter western portion. Araucaria attain large sizes and high longevity but is unable to regenerate under the shade cast by angiosperm canopies and need large-scale disturbances for successfully complete their life-cycles. This cycle has been synthesised in the non-equilibrium Lozenge model of forest dynamics. Regeneration opportunities arise from the frequent multiple treefall gaps produced by the tornado and windstorm-prone climate of subtropical South America and by the grazing-, fire-, and nurse-plant successional dynamics of the forest-grassland mosaic. Dispersal is mediated by a complex web of interactions with birds and mammals. A review of the dynamics of southern Oceanic Temperate Forests indicates that the dynamics of the AMF fits a prevailing pattern in these forests that corresponds to the Lozenge model. Deforestation and degradation by logging and cattle grazing have impacted most of the AMF original range. Similarly to what happened to Agathis australis in New Zealand, the establishment of commercial plantations still need incentives and research to thrive and produce large-scale environmental benefits. [ABSTRACT FROM AUTHOR]

Understanding the drivers of greenhouse gas (GHG) emissions is one of the most critical global environmental challenges to mitigate the increasing global temperature. Nitrous oxide (N2O) emissions are highly variable in space and time and are controlled by multiple proximal drivers, that is, those that affect N2O emissions directly and in short timescales, and distal or indirect drivers that influence emissions over long timescales. Here we present a quantification of N2O emissions in grasslands and forests throughout the Pampas and the Semiarid Chaco in Argentina and reveal distal and proximal drivers, analyzing them in both spatial and temporal models. We measured N2O emissions, soil and climate variables monthly in nine sites over two years. Mean annual temperature and the following soil properties: phosphorous availability, carbon:nitrogen ratio, clay and sand percentages were the main distal drivers controlling N2O emissions in the spatial model, while among proximal drivers, only soil nitrate contents were positively related to N2O emissions. When considering the seasonal variability of N2O emissions (temporal model), we found that emissions were positively related to proximal drivers, such as soil nitrate and soil temperature. Our results show that soil N2O emission drivers differ between spatial and temporal models in natural grasslands and forests, explaining up to 85 and 56% of variations in N2O emissions, respectively. Temperature increased N2O emissions in both spatial and temporal models; therefore, future global warming may increase background emissions from natural ecosystems with important positive feedbacks on the earth system warming. [ABSTRACT FROM AUTHOR]

Aims: Trithrinax campestris is one of the palm species with the southernmost distribution in the Neotropics. Despite that the vegetation types in which T. campestris occurs are nowadays heavily threatened by land use and land cover changes, their floristic composition and structure are still to be documented. In order to characterize T. campestris habitats, the aim of this study was to describe the floristic composition of the vegetation types in which this palm occurs and their relationships with different environmental factors. Study area: The survey was conducted in central Argentina in an area comprising the southern extreme of the distribution of T. campestris in the following phytogeographic areas: Espinal, Lowland and Mountain Chaco. Methods: Following the Braun-Blanquet approach we collected 92 floristic relevés recording a total of 601 vascular plant species. Vegetation was classified through the ISOPAM hierarchical analysis. Bioclimatic and elevation data were related to the floristic data through the ISOMAP ordination. Remote-sensed images (Landsat TM, ETM+ and OLI) were used to characterize the fire frequency in the 92 stands. Results: Four vegetation types that differed in floristic composition and in diagnostic species were discriminated: 1.1 Celtis tala/Sida rhombifolia closed forest; 1.2 Aspidosperma quebracho-blanco/Prosopis kuntzei open forest; 2.1 Jarava pseudoichu/Vachellia caven open savanna; and 2.2 Acalypha variabilis/Nassella cordobensis scrubland. The ISOMAP ordination showed that differences in floristic composition were related to elevation, topography and climatic variables. Out of the 92 stands, only 21 showed the occurrence of fires during the period 1999-2018. Conclusions: Our results evidenced that vegetation types (forests, savannas and scrublands) comprising T. campestris developed in a wide range of environmental conditions. This is the first study that focuses on all vegetation types in which T. campestris occurs in central Argentina and it is relevant for conservation and sustainable management of the only native palm species in the flora of this part of the country. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos de Desarrollo Rural is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Viscacha rats (genus Tympanoctomys Yepes, 1942) are ecologically, physiologically, and behaviorally unusual octodontid rodents endemic to the Monte and Patagonian desert biomes of Argentina. The geographic ranges of the different species of Tympanoctomys have been described in general terms but have not been associated with spatial and climate data. Within species, populations are patchily distributed and genetically distinct. We investigated the predicted distribution of Tympanoctomys and the influence of climate fluctuations on their geographic range in historical, current, and future, scenarios. Our objectives were to characterize the environmental niche of the genus, propose a paleoclimatic context for the oldest fossils, characterize the environmental niches for T. barrerae and T. kirchnerorum , and forecast potential future distributions for these taxa. Ecological niche models were constructed using occurrence records from 1941 to the present wherein we identified several precipitation and temperature variables as important predictors of the geographic distributions of the genus, and the species T. barrerae and T. kirchnerorum. Based on our models' results, we hypothesize that the distribution of Tympanoctomys has contracted from historical to modern times. At the species level, T. kirchnerorum likely experienced the most dramatic change, suffering a large contraction of its historical distribution resulting in its limited present distribution. Given these findings, projected future climate fluctuations and global warming are expected to affect the distributions and persistence of these species. [ABSTRACT FROM AUTHOR]

Glacial and periglacial basins contain the largest reserves of fresh water in the world. These areas are extremely sensitive to global warming and climate change. The dry Andes of South America are characterized by large periglacial areas. This study focuses on the water isotopic composition and hydrochemistry of a typical periglacial environment of the Andes, in the Vallecitos catchment (2400–5500 m a.s.l.), Cordillera Frontal, Argentina. Detailed fieldwork was conducted between 2013 and 2017 with 240 samples collected for major ions and physicochemical parameters, and 67 samples analysed for 2H and 18O. The chemical composition of precipitation is typical Ca-HCO3, while streams and groundwaters are Ca-MgSO4 type. The isotope content of precipitation shows a wide dispersion. The snow samples are in general more depleted than the rainfall. Some springs vary their composition seasonally, associated to the melting of perennial snow patches. In general, all samples from the upper basin present depleted isotope contents related to recharge at higher altitudes, whereas samples from the lower basin show more enriched values. Intermediate compositions reflect the melting of snow and degrading ice-rich permafrost. These results will give a better understanding of the dynamics of water to manage water resources. [ABSTRACT FROM AUTHOR]