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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]

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]

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]

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]

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]

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.)

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]

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]

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]

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]

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.)

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]

Identification and validation of atmospheric extremes are essential to monitoring climate change, to addressing engineering and safety concerns, and to promoting technological advancement. An international World Meteorological Organization evaluation committee has critically adjudicated and recommended acceptance of two lightning megaflash events (horizontal mesoscale lightning discharges of >100 km in length) as new global extremes using analysis of Geostationary Lightning Mapper data. The world's greatest extent for an individual lightning flash is a single flash that covered a horizontal distance of 709 ± 8 km (441 ± 5 mi) across parts of southern Brazil on 31 October 2018. The greatest duration for a single lightning flash is 16.730 ± 0.002 s from a flash that developed continuously over northern Argentina on 4 March 2019. Plain Language Summary: Analysis of new satellite data has identified lightning extremes for horizontal distance (709 km) and greatest duration (16.730 s). Key Points: Analysis of new satellite data identifies far‐larger lightning flashes (termed "megaflashes"; flashes > 100 km) than previously detectedTwo megaflash events are identified from space that exceed global lightning extremes (horizontal length, duration) by a factor of twoThe new megaflash extremes: horizontal distance is 709 km on 31 October 2018 (Brazil); duration is 16.730 s on 4 March 2019 (Argentina) [ABSTRACT FROM AUTHOR]

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Copyright of Cuadernos de Investigación Geográfica is the property of Universidad de la Rioja, Servicio de Publicaciones 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.)

In this work we analyze potential environmental drivers of malaria cases in Northwestern Argentina. We inspect causal links between malaria and climatic variables by means of the convergent cross mapping technique, which provides a causality criterion from the theory of dynamic systems. Analysis is based on 12 years of weekly malaria P. vivax cases in Tartagal, Salta, Argentina—at the southern fringe of malaria incidence in the Americas—together with humidity and temperature time-series spanning the same period. Our results show that there are causal links between malaria cases and both maximum temperature, with a delay of five weeks, and minimum temperature, with delays of zero and twenty two weeks. Humidity is also a driver of malaria cases, with thirteen weeks delay between cause and effect. Furthermore we also determined the sign and strength of the effects. Temperature has always a positive non-linear effect on cases, with maximum temperature effects more pronounced above 25°C and minimum above 17°C, while effects of humidity are more intricate: maximum humidity above 85% has a negative effect, whereas minimum humidity has a positive effect on cases. These results might be signaling processes operating at short (below 5 weeks) and long (over 12 weeks) time delays, corresponding to effects related to parasite cycle and mosquito population dynamics respectively. The non-linearities found for the strength of the effect of temperature on malaria cases make warmer areas more prone to higher increases in the disease incidence. Moreover, our results indicate that an increase of extreme weather events could enhance the risks of malaria spreading and re-emergence beyond the current distribution. Both situations, warmer climate and increase of extreme events, will be remarkably increased by the end of the century in this hot spot of climate change. [ABSTRACT FROM AUTHOR]

Amphibians are the most vulnerable vertebrates to biodiversity loss mediated by habitat destruction, climate change and diseases. Informed conservation management requires improving the taxonomy of anurans to assess reliably the species' geographic range. The genus Odontophrynus that is geographically refined to Argentina, Bolivia, Brazil, Uruguay and Paraguay includes currently 12 nominal species with many populations of uncertain taxonomic assignment and subsequently unclear geographic ranges. In this study, we applied integrative taxonomic methods combining molecular (mitochondrial 16S gene), allozyme, morphological and bioacoustic data to delimit species of the genus Odontophrynus sampled from throughout Argentina where most species occur. The combined evidence demonstrates one case of cryptic diversity and another of overestimation of species richness. The populations referred to as O. americanus comprise at least three species. In contrast, O. achalensis and O. barrioi represent junior synonyms of the phenotypically plastic species O. occidentalis. We conclude that each of the four species occurring in Argentina inhabits medium to large areas. The Red List classification is currently "Least Concern". We also propose a phylogenetic hypothesis for the genus and associated genera Macrogenioglottus and Proceratophrys (Odontophrynidae). [ABSTRACT FROM AUTHOR]

Background. Climate change is one of the greatest threats to biodiversity, pushing species to shift their distribution ranges and making existing protected areas inadequate. Estimating species distribution and potential modifications under climate change are then necessary for adjusting conservation and management plans; this is especially true for endangered species. An example of this issue is the huemul (Hippocamelus bisulcus), an endemic endangered deer from the southern Andes Range, with less than 2,000 individuals. It is distributed in fragmented populations along a 2,000 km latitudinal gradient, in Chile and Argentina. Several threats have reduced its distribution to <50% of its former range. Methods. To estimate its potential distribution and protected areas effectiveness, we constructed a species distribution model using 2,813 huemul presence points throughout its whole distribution range, together with 19 bioclimatic layers and altitude information from Worldclim. Its current distribution was projected for years 2050 and 2070 using five different Global Climate Models estimated for scenarios representing two carbon Representative Concentration Routes (RCP)RCP4.5 and RCP6.0. Results. Based on current huemul habitat variables, we estimated 91,617 km² of suitable habitat. In future scenarios of climate change, there was a loss of suitable habitat due to altitudinal and latitudinal variation. Future projections showed a decrease of 59.86-60.26% for the year 2050 and 58.57-64.34% for the year 2070 according to RCP4.5 and RCP6.0, respectively. Protected areas only covered only 36.18% of the present distribution, 38.57-34.94% for the year 2050 and 30.79-31.94% for 2070 under climate change scenarios. Discussion. Modeling current and future huemul distributions should allow the establishment of priority conservation areas in which to focus efforts and funds, especially areas without official protection. In this way, we can improve management in areas heavily affected by climate change to help ensure the persistence of this deer and other species under similar circumstances worldwide. [ABSTRACT FROM AUTHOR]

A streamflow drought climatology was developed over the Central Andes of Argentina, a semi-arid region highly vulnerable to climatic variations, based on the analysis of daily historical streamflow records. A threshold level approach was applied on a daily basis for three different severity levels in order to depict the main characteristics of droughts – number of drought events, mean duration and mean severity – over the period 1957–2014. Based on three annual indices that summarize the frequency of drought events, their duration and severity, we identified the main regional dry periods and the main modes of variability through an empirical decomposition. These modes are linked to La Niña conditions on inter-annual time scales and the Pacific Decadal Oscillation for the decadal variations, showing the influence of the tropical Pacific Ocean in the development of streamflow drought conditions and its relevance for potential predictability of hydroclimatic variations over the region. [ABSTRACT FROM AUTHOR]

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Climate change has led to an increase in extreme weather events and desertification of vast areas of southern Argentina. Water shortages are a major concern, and this problem is expected to be exacerbated in the future. An exploration program was undertaken to investigate the groundwater occurrence in areas of the Chubut River basin in order to provide new supply options for pastoral farming. The investigation involved the drilling of exploration holes and construction of bores for long-term monitoring. Water quality and hydraulic test data were also collected. Findings from the study indicate that alluvial sediments extend to a maximum of 45 m below the surface, and are underlain by a sequence of clays and subordinated sands that exceed 100 m in thickness. The bulk of groundwater lies within the shallow sediments, which act as an unconfined aquifer. Hydraulic conductivities up to 10 m/day were estimated from pumping tests, although granulometric analyses indicate that higher values may occur. Chemical characterization indicates that waters are typically fresh, low in sodium, and largely suitable for stock-grazing or horticulture. Anomalous salinities at one of the sites are likely due to the effects of a nearby waste dump. Even though further work is required, the study contributes to a better understanding of the dynamics of the hydrogeological system in the basin under a warming climate, and provides useful information for the expansion of economic activities in remote communities of Argentina. [ABSTRACT FROM AUTHOR]

We analyze the influence of climate change on soybean yields in a multivariate time-series framework for a major soybean producer and exporter—Argentina. Long-run relationships are found in partial systems involving climatic, technological, and economic factors. Automatic model selection simplifies dynamic specification for a model of soybean yields and permits encompassing tests of different economic hypotheses. Soybean yields adjust to disequilibria that reflect technological improvements to seed and crops practices. Climatic effects include (a) a positive effect from increased CO 2 concentrations, which may capture accelerated photosynthesis, and (b) a negative effect from high local temperatures, which could increase with continued global warming. [ABSTRACT FROM AUTHOR]

The core crop region of the Humid Pampa is one of the most productive agricultural lands around the world and depends highly on climate conditions. This study assesses climate variability, climate extremes, and observed and projected climate changes there, using 1911–2019 observations and CMIP5 model simulations. Since 1970, the annual mean temperature has risen by 1 °C and the mean annual minimum and maximum temperatures by 2 and 0.5 °C, respectively. The frequency of warm days and nights increased, and cold days and nights decreased. Heatwaves became longer and more intense, and cold waves decreased with less frost events. Annual precipitation increased by 10% from 1911, mainly in summer, and years with excess precipitation outnumbered those with a deficit. Both intense precipitation events and consecutive dry days grew, suggesting more annual precipitation falling on fewer days. Projections show a warming of 1 °C by 2035, regardless of the scenario. From then on until 2100, mean temperature will increase by 2 and 3–3.5 °C in the RCP4.5 and RCP8.5 scenarios, respectively. Annual precipitation will grow 8 and 16% from current values by 2100 in the RCP4.5 and RCP8.5 scenarios, respectively. No major precipitation changes are projected in the RCP2.6 scenario. [ABSTRACT FROM AUTHOR]

Eucalyptus grandis and E. dunnii have high productive potential in the South of Brazil, Uruguay, and central Argentina. This is based on the similarity of the climate and soil of these areas, which form an eco-region called Campos. However, previous results show that these species have differences in their distribution caused by the prioritization of Uruguayan soils for forestry, explained by the particular conditions of each site. In this study, the site variables (climate, soil, and topography) that better explain the distribution of both species were identified, and prediction models of current and future distribution were adjusted for different climate change scenarios (years 2050 and 2070). The distribution of E. grandis was associated with soil parameters, whereas for E. dunnii a greater effect of the climatic variables was observed. The ensemble biomod2 model was the most precise with regard to predicting the habitat for both species with respect to the simple models evaluated. For E. dunnii, the average values of the AUC, Kappa, and TSS index were 0.98, 0.88, and 0.77, respectively. For E. grandis, their values were 0.97, 0.86, and 0.80, respectively. In the projections of climatic change, the distribution of E. grandis occurrence remains practically unchanged, even in the scenarios of temperature increase. However, current distribution of E. dunnii shows high susceptibility in a scenario of increased temperature, to the point that most of the area currently planted may be at risk. Our results might be useful to political government and foresters for decision making in terms of future planted areas. [ABSTRACT FROM AUTHOR]

Sorghum is the world's fifth major cereal in terms of production and acreage. It is expected that its growth will be affected by the increase in air temperature, an important component of global climate change. Our objective was to use the Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model to (a) evaluate the impact of climate warming on forage and grain sorghum production in Argentina and (b) to analyze to what extent yield changes were associated with changes in water or nitrogen stress days. For model calibration, we used previous information related to the morpho-physiological characteristics of both sorghum types and several soil parameters. We then used multiyear field data of sorghum yields for model validation. Yield simulations were conducted under three possible climate change scenarios: 1, 2, and 4 °C increase in mean annual temperature. ALMANAC successfully simulated mean yields of forage and grain sorghum: root mean square error (RMSE): 2.6 and 1.0 Mg ha−1, respectively. Forage yield increased 0.53 Mg ha−1, and grain yield decreased 0.27 Mg ha−1 for each degree of increase in mean annual temperature. Yields of forage sorghum tended to be negatively associated with nitrogen stress (r = −0.94), while grain sorghum yield was negatively associated with water stress (r = −0.99). The information generated allows anticipating future changes in crop management and genetic improvement programs in order to reduce the yield vulnerability. [ABSTRACT FROM AUTHOR]