Search

The out‐of‐sight groundwater and visible but much less extensive surface waters on land constitute a linked terrestrial water system around the planet. Research is crucial for our understanding of these terrestrial water system links and interactions with other geosystems and key challenges of Earth System change. This study uses a scoping review approach to discuss and identify topical, methodological and geographical gaps and priorities for research on these links and interactions of the coupled ground‐ and surface water (GSW) system at scales of whole‐catchments or greater. Results show that the large‐scale GSW system is considered in just a small part (0.4%–0.8%) of all studies (order of 105 for each topic) of either groundwater or surface water flow, storage, or quality at any scale. While relatively many of the large‐scale GSW studies consider links with the atmosphere or climate (8%–43%), considerably fewer address links with: (a) the cryosphere or coastal ocean as additional interacting geosystems (5%–9%); (b) change drivers/pressures of land‐use, water use, or the energy or food nexus (2%–12%); (c) change impacts related to health, biodiversity or ecosystem services (1%–4%). Methodologically, use of remote sensing data and participatory methods is small, while South America and Africa emerge as the least studied geographic regions. The paper discusses why these topical, methodological and geographical findings indicate important research gaps and priorities for the large‐scale coupled terrestrial GSW system and its roles in the future of the Earth System. Plain Language Summary: The water on the land surface (surface water) and that beneath it (groundwater), along with the water that is continuously and increasingly used and managed in human societies, are connected and constitute a coherent natural‐social water system around the world. Many unknowns and open questions remain for how the small‐scale variations add up to large‐scale variability and change of this water system on land, as an integral part of the whole Earth System. Relevant research is crucial for reducing the unknowns and answering the questions, and this study's scoping review aims to assess how they have been addressed in published research so far. The aim is to identify key research gaps and priorities for further research on how the integrated water system on land functions and evolves on large scales, from whole hydrological catchments and in multiple catchments around the world up to global scale. The scoping review results show key research gaps and priorities to be the coupling of surface water and groundwater on land, and the interactions of this coupled water system with other parts and major challenges of the Earth System. Geographically, the gaps and priorities emerge as particularly large and urgent for South America and Africa. Key Points: Coupling of the ground‐surface water system is a key gap in terrestrial water research, particularly at large scalesResearch on terrestrial water interactions with other geospheres and key challenges of Earth System change is rare but impactfulMajor geographic gaps in research on the large‐scale coupled terrestrial water system emerge for South America and Africa [ABSTRACT FROM AUTHOR]

Ants, an ecologically successful and numerically dominant group of animals, play key ecological roles as soil engineers, predators, nutrient recyclers, and regulators of plant growth and reproduction in most terrestrial ecosystems. Further, ants are widely used as bioindicators of the ecological impact of land use. We gathered information of ant species in the Atlantic Forest of South America. The ATLANTIC ANTS data set, which is part of the ATLANTIC SERIES data papers, is a compilation of ant records from collections (18,713 records), unpublished data (29,651 records), and published sources (106,910 records; 1,059 references), including papers, theses, dissertations, and book chapters published from 1886 to 2020. In total, the data set contains 153,818 ant records from 7,636 study locations in the Atlantic Forest, representing 10 subfamilies, 99 genera, 1,114 ant species identified with updated taxonomic certainty, and 2,235 morphospecies codes. Our data set reflects the heterogeneity in ant records, which include ants sampled at the beginning of the taxonomic history of myrmecology (the 19th and 20th centuries) and more recent ant surveys designed to address specific questions in ecology and biology. The data set can be used by researchers to develop strategies to deal with different macroecological and region‐wide questions, focusing on assemblages, species occurrences, and distribution patterns. Furthermore, the data can be used to assess the consequences of changes in land use in the Atlantic Forest on different ecological processes. No copyright restrictions apply to the use of this data set, but we request that authors cite this data paper when using these data in publications or teaching events. [ABSTRACT FROM AUTHOR]

In a jungle environment where jaguars are considered human, systems thinking has evolved in unexpected ways. Although systems thinking is commonly seen as a product of the Western world, other cultures have developed their own versions with unique characteristics. In this article, we explore Amazonian systems thinking, which has similarities to modern Western systems thinking, as well as differences that may inspire the evolution of systems approaches worldwide. We will discuss the contributions of Amazonian systems thinking particularly to find answers to the planet's ecological and sustainability problems, such as climate change and mass extinction of species, among others. We will present the systems thinking that emerged in some Amazonian communities, how it relates to mainstream Western systems thinking, and focus on some unique aspects of Amazonian systems thinking. This paper is based on the ethnographic work of Gerardo Reichel‐Dolmatoff and other anthropologists who have studied Amazonian communities for decades. [ABSTRACT FROM AUTHOR]

Pasturelands are globally extensive, sensitive to climate, and support livestock production systems that provide an essential source of food in many parts of the world. In this paper, we integrate information from remote sensing, global climate, and land use databases to improve understanding of the resilience and resistance of this ecologically vulnerable and societally critical land use. To characterize the effect of climate on pastureland productivity at global scale, we analyze the relationship between satellite‐derived enhanced vegetation index data from MODIS and gridded precipitation data from CHIRPS at 3‐ and 6‐month time lags. To account for the effects of different production systems, we stratify our analysis by agroecological zones and by rangeland versus mixed crop‐livestock systems. Results show that 14.5% of global pasturelands experienced statistically significant greening or browning trends over the 15‐year study period, with the majority of these locations showing greening. In arid ecosystems, precipitation and lagged vegetation index anomalies explain up to 69% of variation in vegetation productivity in both crop‐livestock and rangeland‐based production systems. Livestock production systems in Australia are least resistant to contemporaneous and short‐term precipitation anomalies, while arid livestock production systems in Latin America are least resilient to short‐term vegetation greenness anomalies. Because many arid regions of the world are projected to experience decreased total precipitation and increased precipitation variability in the coming decades, improved understanding regarding the sensitivity of pasturelands to the joint effects of climate change and livestock production systems is required to support sustainable land management in global pasturelands. Plain Language Summary: Pastures, which provide food for livestock, are the most extensive land use on the planet, and their productivity depends on the timing and amount of rainfall they receive. In this paper, we use data on vegetation productivity, rainfall, and land use in order to determine the ability of pastures to remain unaffected by a disturbance and the time required for pastures to recover following a disturbance. To determine the effects of rainfall on pastures, we analyze the relationship between productivity and rainfall at 3‐ and 6‐month time intervals. We also take into account pasture management and whether pastures are located in dry or humid areas of the world. In dry regions, rain from the current season, rain from the last two seasons, and vegetation productivity from the previous growing season explain nearly 70% of current season vegetation productivity. Pastures in Australia are least capable of withstanding rainfall deficits, while pastures in Latin America recover more slowly after drought compared to other regions. Dry regions of the world are predicted to receive less rain less regularly in the coming decades, so improved understanding of the sensitivity of pastures to expected changes in rainfall will help support sustainable management of global pastures. Key Points: In Australia, pasturelands have both low resistance and low resilience relative to other regions across the worldSouthern South America has the lowest resilience globally, which is indicative of slow vegetation recovery after a disturbanceA total of 14.5% of global pasturelands experienced greening or browning trends, with the majority of these locations showing greening [ABSTRACT FROM AUTHOR]

The past forty years have witnessed a rapid expansion of grain and oilseed production in the southern hemisphere, particularly in South America. The growth of southern hemisphere production is significant, not only because it has increased supplies to meet growing world food needs but also because it has effectively shortened the global crop growing cycle from twelve months to six months. In this paper, we develop and analyze a semi‐annual stochastic spatial–temporal equilibrium model of a generic agricultural market with two major exporting regions, North and South, which plant and harvest at different times of the year. As a case study, we calibrate our model parameters to reflect the stylized facts of the global soybean market between 1980 and 2019, with the United States serving as North and Brazil and Argentina serving as South. We find that more balanced production, with both hemispheres producing nearly equal amounts at different times of the year, has, from a global perspective, shortened the traditional crop "season" from twelve months to six months, allowing semi‐annual adjustments to planned production that stabilize supply and prices in all regions while reducing global inventories. [ABSTRACT FROM AUTHOR]

Biodiversity inventories contain important information about species richness, community structure, and composition, and are the first step in developing any conservation and mitigation strategies. The Atlantic Forest of South America is home to around 334 species of small‐, medium‐, and large‐sized mammals, and is currently restricted to less than 12% of its original cover. Here, we present the ATLANTIC MAMMALS, an open data set on information on medium‐ and large‐sized mammal assemblages in the Atlantic Forest of Brazil, Paraguay, and Argentina. A total of 129 studies were compiled, including published and in press peer‐reviewed papers, book chapters, theses and unpublished data. We mapped 244 assemblages, eight orders, 63 genera, and 94 species (24 of which are classified as threatened by the IUCN Red List) distributed in 128 protected and 116 unprotected areas. Species richness of the mammalian assemblages varied from 1 to 39 species (mean 15). The most recorded species in the entire biome was Dasypus novemcinctus, followed by Cerdocyon thous and Procyon cancrivorous. These data can be useful in support of macroecological studies and conservation planning strategies. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. [ABSTRACT FROM AUTHOR]

This paper explores the relationships between proactive environmental strategy (PES) and internationalization in emerging markets multinationals from Latin America (Multilatinas). Drawing on the resource‐based view and institutional theory and using a sample of 86 listed firms during the period 2013–2017, we find that Multilatinas with higher tiers of PES are associated with higher degrees of geographic international diversification. Because adopting PES is directly conditioned by institutional pressures to comply with stakeholders' regulations and expectations, Multilatinas that implement advanced PES will be able to achieve a higher level of international presence in foreign markets. Our results also reveal that board independence positively moderates the relationship between PES and geographic international diversification. Specifically, board independence provides Multilatinas with the opportunity to integrate valuable knowledge and expertise and thus to take advantage of implementing advanced PES to achieve even greater levels of internationalization. This study expands understanding of how environmental strategies influence internationalization of firms in the Latin American business context. [ABSTRACT FROM AUTHOR]

Aim: The efficiency of animal‐mediated seed dispersal is threatened by the decline of animal populations, especially in tropical forests. We hypothesise that large‐seeded plants with animal‐mediated dispersal tend to have limited geographic ranges and face an increased risk of extinction due to the potential decline in seed dispersal by large‐bodied fruit‐eating and seed‐dispersing animals (frugivores). Location: Atlantic Forest, Brazil, South America. Taxon: Angiosperms. Methods: First, we collected dispersal‐related traits (dispersal syndrome, fruit size, and seed size), growth form (tree, climber, and other) and preferred vegetation type (open and closed) data for 1052 Atlantic Forest plant species. Next, we integrated these with occurrence records, extinction risk assessments, and phylogenetic trees. Finally, we performed phylogenetic generalised least squares regressions to test the direct and interactive effects of dispersal‐related traits and vegetation type on geographical range size. Results: Large‐seeded species had smaller range sizes than small‐seeded species, but only for species with animal‐mediated dispersal, not for those dispersed by abiotic mechanisms. However, plants with abiotic dispersal had overall smaller range sizes than plants with animal‐mediated dispersal. Furthermore, we found that species restricted to forests had smaller ranges than those occurring in open or mixed vegetation. Finally, at least 29% of the Atlantic Forest flora is threatened by extinction, but this was not related to plant dispersal syndromes. Main Conclusions: Large‐seeded plants with animal‐mediated dispersal may be suffering from dispersal limitation, potentially due to past and ongoing defaunation of large‐bodied frugivores, leading to small range sizes. Other factors, such as deforestation and fragmentation, will probably modulate the effects of dispersal on range size, and ultimately extinction. Our study sheds light on the relationship between plant traits, mutualistic interactions, and distribution that are key to the functioning of tropical forests. [ABSTRACT FROM AUTHOR]

Pathogen spillover corresponds to the transmission of a pathogen or parasite from an original host species to a novel host species, preluding disease emergence. Understanding the interacting factors that lead to pathogen transmission in a zoonotic cycle could help identify novel hosts of pathogens and the patterns that lead to disease emergence. We hypothesize that ecological and biogeographic factors drive host encounters, infection susceptibility, and cross‐species spillover transmission. Using a rodent–ectoparasite system in the Neotropics, with shared ectoparasite associations as a proxy for ecological interaction between rodent species, we assessed relationships between rodents using geographic range, phylogenetic relatedness, and ectoparasite associations to determine the roles of generalist and specialist hosts in the transmission cycle of hantavirus. A total of 50 rodent species were ranked on their centrality in a network model based on ectoparasites sharing. Geographic proximity and phylogenetic relatedness were predictors for rodents to share ectoparasite species and were associated with shorter network path distance between rodents through shared ectoparasites. The rodent–ectoparasite network model successfully predicted independent data of seven known hantavirus hosts. The model predicted five novel rodent species as potential, unrecognized hantavirus hosts in South America. Findings suggest that ectoparasite data, geographic range, and phylogenetic relatedness of wildlife species could help predict novel hosts susceptible to infection and possible transmission of zoonotic pathogens. Hantavirus is a high‐consequence zoonotic pathogen with documented animal‐to‐animal, animal‐to‐human, and human‐to‐human transmission. Predictions of new rodent hosts can guide active epidemiological surveillance in specific areas and wildlife species to mitigate hantavirus spillover transmission risk from rodents to humans. This study supports the idea that ectoparasite relationships among rodents are a proxy of host species interactions and can inform transmission cycles of diverse pathogens circulating in wildlife disease systems, including wildlife viruses with epidemic potential, such as hantavirus. [ABSTRACT FROM AUTHOR]

The paper examines the influence of the structural breaks on the optimal weights, hedge ratios and hedge effectiveness index (HEI) of risk‐minimizing portfolios composed of S&P500 and selected emerging markets' indices from East Europe, Asia and South America. We employ a bivariate DCC‐EGARCH models without and with structural breaks and we find better estimation features when structural breaks are included in the model. However, we do not find evidence that insertion of structural breaks increases portfolio hedging performances. The differences that exist between optimal weights, hedge ratios and HEI values are so small that tangible economic benefit for international investors do not exist. [ABSTRACT FROM AUTHOR]

Summary: Quinoa is an agriculturally important crop species originally domesticated in the Andes of central South America. One of its most important phenotypic traits is seed colour. Seed colour variation is determined by contrasting abundance of betalains, a class of strong antioxidant and free radicals scavenging colour pigments only found in plants of the order Caryophyllales. However, the genetic basis for these pigments in seeds remains to be identified. Here we demonstrate the application of machine learning (extreme gradient boosting) to identify genetic variants predictive of seed colour. We show that extreme gradient boosting outperforms the classical genome‐wide association approach. We provide re‐sequencing and phenotypic data for 156 South American quinoa accessions and identify candidate genes potentially controlling betalain content in quinoa seeds. Genes identified include novel cytochrome P450 genes and known members of the betalain synthesis pathway, as well as genes annotated as being involved in seed development. Our work showcases the power of modern machine learning methods to extract biologically meaningful information from large sequencing data sets. [ABSTRACT FROM AUTHOR]

Mountainous grasslands in South America, characterized by their high diversity, provide a wide range of contributions to people, including water regulation, soil erosion prevention, livestock feed provision, and preservation of cultural heritage. Prior research has highlighted the significant role of grazing in shaping the diversity and productivity of grassland ecosystems, especially in highly productive, eutrophic systems. In such environments, grazing has been demonstrated to restore grassland plant diversity by reducing primary productivity. However, it remains unclear whether these findings are applicable to South American mountainous grasslands, where plants are adapted to different environmental conditions. To address this uncertainty, we conducted a meta‐analysis of experiments excluding livestock grazing to assess its impact on plant diversity and productivity across mountainous grasslands in South America. In alignment with studies in temperate grasslands, our findings indicated that herbivore exclusion resulted in increased aboveground biomass but reduced species richness and Shannon diversity. The effects of grazing exclusion became more pronounced with longer durations of exclusion; nevertheless, they remained resilient to various climatic conditions, including mean annual precipitation and mean annual temperature, as well as the evolutionary history of grazing. In contrast to results observed in temperate grasslands, the reduction in species richness due to herbivore exclusion was not associated with increased aboveground biomass. This suggests that the processes governing (sub)tropical grassland plant diversity may differ from those in temperate grasslands. Consequently, further research is necessary to better understand the specific factors influencing plant diversity and productivity in South American montane grasslands and to elucidate the ecological implications of herbivore exclusion in these unique ecosystems. [ABSTRACT FROM AUTHOR]

The latitudinal diversity gradient (LDG) hypothesis has been validated for many taxon groups, but so far, stream diatoms have not conformed to this pattern. Research on diatoms that includes data from South America is lacking, and our study aims to address this knowledge gap. Previous studies have successfully explained stream diatom species richness by considering niche dimensionality of physicochemical variables. Moreover, in southwestern South America, the observed biogeographical pattern differs from LDG and has been shown to be determined by historical factors. We used a dataset comprising 373 records of stream diatom communities located between 35° S and 52° S latitude, southwestern South America. The dataset included physicochemical river water variables, climate data, and ice sheet cover from the Last Glacial Maximum. We explored geographical patterns of diatom species richness and evaluated 12 different causal mechanisms, including climate‐related theories, physicochemical and climatical exploratory analyses, historical factors, and niche dimensionality. A metacommunity analysis was conducted to evaluate the possible nested structure due to historical factors. We observed an increase in diatom species richness from south to north. Models containing both physicochemical and climatic predictors explained the highest proportion of variation in the data. Silica, which was correlated with latitude, and flow velocity, which did not show any spatial pattern, were the most important predictors. Historical factors and nested structure did not play any role. Contrary to what has been reported in the literature, we found no support for climate‐related explanations of species richness. Instead, theories related to niche dimensionality and local factors provided better explanations, consistent with previous related research. We suggest that the increase in diatom richness in the north of our study region is due to a higher nutrient supply in these rivers, rather than a due to larger species pool in the area. [ABSTRACT FROM AUTHOR]

Amphibians and reptiles are ectothermic animals and therefore depend on environmental temperatures to maintain their physiological functions. Despite being poorly documented, data on thermal behavioral thresholds to avoid overheating in their habitats are essential to improve the understanding of their thermal ecology and physiology. Here we provide a data set of 312 individual voluntary thermal maximum (VTMax) values, the maximum temperature tolerated by individuals before actively moving to a colder place, for 53 species of amphibians and reptiles of the Atlantic Forest and Cerrado savannas of southeastern South America. Voluntary thermal maximum values were recorded as the body temperature at which the individuals exited a heating box experimental setup. This data set comprises 25 species of 15 genera and eight families of amphibians and 28 species of 24 genera and 12 families of reptiles. Of the total number of individual records, 67.9% derived from the Cerrado and 32.0% derived from the Atlantic Forest ecoregions. Overall, lizards had higher VTMax than amphibians and snakes, and individuals in the Atlantic Forest had overall higher VTMax values than the ones in Cerrado. This data set is the first to compile VTMax values for South American herpetofauna, along with detailed experimental information such as heating rates and time to reach VTMax. This data set provides a baseline for understanding thermal tolerances and requirements of Neotropical ectothermic vertebrate species, which might be useful for future research on the impact of climate change and to test novel ecological hypotheses. There are no copyright or proprietary restrictions except that this data paper should be cited when data are used for publications. In addition, the authors would appreciated being informed of research projects or teaching purposes when these data are used. [ABSTRACT FROM AUTHOR]

Body mass is one of the most important phenotypic attributes in animal ecology and life history. This trait is widely used in the fields of ecology and macroevolution, since it influences physiology, morphological functions, and a myriad of ecological and social interactions. In this data set, our aim was to gather a comprehensive bird and mammal body mass data set from northern South America. We report body mass, discriminated by sex, for 42,022 individual birds and 7,441 mammals representing 1,317 bird species (69% of Colombia's avifauna) and 270 mammal species (51% of Colombian mammals) from the Neotropics. The data were sourced from vouchers collected between 1942 and 2020 and from individuals captured and released at banding stations over the last two decades for birds (2000–2020) and the last decade for mammals (2010–2020), by 10 research groups and institutions in Colombia. This data set fills gaps identified in other similar databases, as it focuses on northern South America, a highly diverse Neotropical region often underrepresented in morphological data sets. We provide wide taxonomic coverage for studies interested in information both at regional and local scales. There are no copyright restrictions; the present data paper should be appropriately cited when data are used for publication. The authors would appreciate learning about research projects, teaching exercises, and other uses given to this data set and are open to contribute in further collaborations using these data. [ABSTRACT FROM AUTHOR]

Copyright of Methods in Ecology & Evolution is the property of Wiley-Blackwell 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.)

Mineral dust accumulated on the ocean floor is an important archive for reconstructing past atmospheric circulation changes and climatological conditions in the source areas. Dust emitted from Southern Hemisphere dust sources is widely deposited over the oceans. However, there are few records of dust deposition over the open ocean, and a large need for extended geographical coverage exists. We present a large data set (134 surface sediment samples) of Late Holocene dust deposition from seafloor surface sediments covering the entire South Atlantic Ocean. Polymodal grain‐size distributions of the lithogenic fraction indicate that the sediments are composed of multiple sediment components. By using end‐member modeling, we attempt to disentangle the dust signal from non‐aeolian sediments. Combined with 230Th‐normalized lithogenic fluxes, we quantified the specific deposition fluxes for mineral dust, crrent‐sorted sediments and ice‐rafted debris (IRD). Although the method could not completely separate the different components in every region, it shows that dust deposition off the most prominent dust source for the South Atlantic Ocean—southern South America—amounts up to approximately 0.7 g cm−2 Kyr−1 and decreases downwind. Bottom‐current‐sorted sediments and IRD are mostly concentrated around the continental margins. The ratio of the coarse to fine dust end members reveals input from north African dust sources to the South Atlantic. The majority of the observations are in good agreement with new model simulations. This extensive and relevant data set of dust grain size and deposition fluxes to the South Atlantic could be used to calibrate and validate further model simulations. Plain Language Summary: Ocean records of mineral dust can be used to reconstruct past climatic changes such as wind strength and aridity in the source regions, and also marine biological productivity. However, in the remote open ocean, dust samples are difficult to obtain and therefore records are sparse. We present a large data set of dust deposition, determined from the top centimeter of ocean floor sediments, covering the entire South Atlantic Ocean. These appeared to be complex mixtures of different sediment types, which we attempted to unmix mathematically. This resulted in four individual components, which are fine and coarse mineral dust, current‐sorted sediments and ice‐rafted debris (IRD). Although the unmixing has its limitations, it shows that the dust deposition off the most prominent dust source for the South Atlantic Ocean—southern South America—is significant and decreases downwind as dust settles during transport across the ocean. Current‐sorted sediments and IRD are mostly concentrated around the continental margins. The results also reveal dust transport across the equator from north African dust sources and show similarities with new model simulations. This extensive and relevant data set of dust grain size and deposition fluxes to the South Atlantic can be used to calibrate and validate further model simulations. Key Points: End‐member (EM) modeling is used to disentangle different sediment components from polymodal grain‐size distributionsCombined with 230Th‐normalized lithogenic fluxes, specific fluxes for dust, current‐sorted sediments and ice‐rafted debris are obtainedThis independent quantification provides more specific dust fluxes compared to global compilations of lithogenic fluxes [ABSTRACT FROM AUTHOR]

Copyright of Regional Science Policy & Practice is the property of Wiley-Blackwell 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.)

Numerical experiments on sensitivity to land surface initializations are frequently conducted to investigate the predictability and uncertainties of hydrometeorological extremes. However, the conventional approaches to soil initialization often assume synchronized extremes over the target region, creating initial conditions that violate the intrinsic spatial pattern of hydrometeorological variability. Here we propose a "Slope" approach to accommodate unsynchronized anomalies, which creates initial conditions of a variable (soil temperature or soil moisture) across a large domain based on the slopes of linear regression between the variable averaged over a small target region and at each grid point in the surrounding regions. Within the target region, the "Slope" approach produces spatial patterns and temporal evolutions of hydrometeorological responses similar to the conventional approach, but generates stronger signals probably due to the nonlocal impact (excluded from the conventional approach). In the surrounding regions, the hydrometeorological responses in the "Slope" approach are consistent with the spatiotemporal variability of the model climate. Slope‐based experiments targeting different adjacent regions produce similar results, suggesting that one ensemble of experiments targeting one region may be sufficient to represent the responses from multiple ensembles each targeting a different region and thus providing the basis for increasing the computational efficiency of some land‐atmosphere interaction studies. While South America is used to demonstrate the concept in this study, the new approach offers the most advantages in regions with spatially unsynchronized or even anti‐phased hydrometeorological extremes. Plain Language Summary: Sensitivity experiments on soil initializations were routinely conducted to study land‐atmosphere interactions in the past two decades. These studies, either imposing soil moisture or temperature anomalies to a small target region and keeping it "normal" elsewhere or imposing similar anomalies across a large domain, cannot account for spatially unsynchronized variations. To address this deficiency, we propose a "Slope" approach to derive the initial conditions based on the slopes of regression between soil temperature or moisture in the target region and its surroundings. Compared to the conventional approaches, the "Slope" approach produces similar hydrometeorological responses over the target region; slight differences exist likely because it also accounts for the nonlocal impact. In the surrounding regions with minimal responses in the conventional approach, the signals in the "Slope" approach are consistent with variabilities from the model climate. In addition, the "Slope" approach can increase the computational efficiency of land‐atmosphere experimental design, since one ensemble of experiments targeting one region can potentially capture the responses from multiple ensembles targeting different adjacent regions. This study uses South America as an example to demonstrate the concept; the advantages of the new approach will be more evident in regions with anti‐phased hydrometeorological extremes. Key Points: A new approach to soil initialization is proposed to account for spatially unsynchronized variability or extremesThe new approach conforms to the intrinsic spatial pattern of hydrometeorological variabilityThe new approach can potentially increase the computational efficiency of experimental design [ABSTRACT FROM AUTHOR]

South America, particularly within its tropical belt, is renowned for its unparalleled high levels of species richness, surpassing other major biomes. Certain neotropical areas harbor fragmented knowledge of insect diversity and face imminent threats from biodiversity loss and climate change. Hence, there is an urgent need for rapid estimation methods to complement slower traditional taxonomic approaches. A variety of algorithms for delimiting species through single‐locus DNA barcodes have been developed and applied for rapid species diversity estimates across diverse taxa. However, tree‐based and distance‐based methods may yield different group assignments, leading to potential overestimation or underestimation of putative species. Here, we investigate the performance of different DNA‐based species delimitation approaches to rapidly estimate the diversity of Polypedilum (Chironomidae, Diptera) in South America. Additionally, we test the hypothesis that significant differences exist in the community structure of Polypedilum fauna between South America and its neighboring regions, particularly the Nearctic. Our analysis encompasses a dataset of 1492 specimens from 598 locations worldwide, with a specific focus on South America. Within this region, we analyzed a subset of 247 specimens reported from 37 locations. Using various methods including the Barcode Index Number (BIN), Bayesian Poisson tree processes (bPTP), multi‐rate Poisson tree processes (mPTP), single‐rate Poisson tree processes (sPTP), and generalized mixed Yule coalescent (sGMYC), we identify molecular operational taxonomic units (MOTUs) ranging from 267 to 520. Our results indicate that the sGMYC method is the most suitable for estimating putative species in our dataset, resulting in the identification of 75 species in the Neotropical region, particularly in South America. Notably, this region exhibited higher species richness in comparison to the Palearctic and Oriental realms. Additionally, our findings suggest potential differences in species composition of Polypedilum fauna between the Neotropical and the adjacent Nearctic realms, highlighting high levels of endemism and species richness in the first. These results support our hypothesis that there are substantial differences exist in species composition between the Polypedilum fauna in South America and the neighboring regions. [ABSTRACT FROM AUTHOR]

Seamounts and ridges are often invoked to explain subduction‐related phenomena such as flat slab generation, but the extent of their involvement remains controversial. An analysis of seismicity in the region of the Pampean flat slab through an application of an automated catalog generation algorithm resulted in 35,924 well constrained local earthquake hypocenters and a total of 12,172 focal mechanisms. Several new features related to the subduction of the Juan Fernandez Ridge (JFR) were discovered, including (a) a series of parallel lineaments of seismicity in the subducted Nazca plate separated by about 50 km and trending about 20°, and (b) a strong spatial correlation between these deeper (>80 km depth) regions of intense seismicity and concentrations of activity in the crust almost directly above it. Focal mechanisms of the deeper events are almost exclusively (∼81%) normal, while those in the crust are predominantly (∼70%) reverse. The deeper lineaments mirror the orientation and spacing of several seamount chains seen on the Nazca plate, suggesting that these patterns are caused by the same types of features at depth. This would imply that relatively minor features persist as slab anomalies long after they are subducted. The correlation of the deeper seismicity that defines these features with seismicity in the mid to lower crust suggests a genetic relation between the two. We postulate that volatiles from the subducted ridges percolate into the South American crust and induce seismicity essentially by fracking it. Plain Language Summary: The ocean floor has many anomalous features such as seamounts and ridges that are believed to have profound consequences for subduction zones. Some of these effects can be illuminated by determining the locations and mechanisms of earthquakes associated with them. Seismic data collected near one of these features, the Juan Fernandez Ridge beneath South America, were analyzed with an automated catalog generation routine to significantly increase the number of well‐constrained earthquake locations from this area. Plots of these new locations reveal patterns in and around the subducted ridge that mirror the distribution of minor ridges on the Nazca plate, suggesting that the consumption of similar ridges is responsible for this activity. Moreover, these patterns are reflected in the patterns of earthquakes in the South American crust directly above them, also suggesting a genetic relationship. We hypothesize that volatiles such as water or carbon dioxide are being released by these subducted ridges, migrating through the South American mantle, and essentially fracking the mid to lower crust by increasing pore pressure. Key Points: Automatically generated catalogs of seismicity in the Pampean flab slab show parallel lineaments of seismicity in the Nazca plateThe lineaments are reflected in the bearing and spacing of seamount chains seen in Nazca plate bathymetryCorrelation of mantle seismicity with that in the crust suggests that subducted ridges release volatiles that induce crustal seismicity [ABSTRACT FROM AUTHOR]

The subduction of an active spreading center generates a clear signature in the temporal evolution of subduction zones. It disrupts the typical arc‐type magmatism and intraplate seismicity, enhances the emplacement of backarc plateau lava and profoundly change the tectonics and topographic relief. These distinct observations are commonly linked to a slab window opening and mantle upwelling. The Chile Triple Junction provides the ideal setup to study the mid‐ocean ridge subduction process where both sides of the spreading center continue to subduct. Here, we use 2‐D numerical petrological‐thermomechanical modeling to focus on transient geodynamic processes caused by mid‐ocean ridge subduction. Model results show slab separation along the ridge axis with the opening of a slab window. During the opening, partial melts from the spreading center migrate toward the subcontinental mantle and high temperatures in the forearc are predicted. The temporal evolution of the modeled temperature is consistent with observed heat flow data, and with magmatism and high‐temperature metamorphism recorded in Chilean forearc rocks. Such migrated partial melts might explain the low viscosity inferred and low seismic velocity anomalies imaged in the slab window beneath South America, and the common geochemical signature of the Chile Ridge, the Taitao Ophiolite and the backarc magmatism. Following slab separation, our models suggest forearc uplift and changes in the stress regime, processes which are consistent with deformation records. Summarizing, our model of the geodynamic evolution of the Chile Ridge subduction provides a consistent framework that explains diverse records of magmatism, metamorphism, deformation and mantle physical properties. Key Points: 2‐D models of mid‐ocean ridge subduction using petrological‐thermomechanical modelingSlab separation leads to the opening of a slab window and the migration of partial melts from the mid‐ocean ridge to the subcontinental mantleModels are consistent with geological, geophysical and geochemical observations in the Chile Triple Junction [ABSTRACT FROM AUTHOR]

Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra‐ and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820–2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell 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 Conservation Biology is the property of Wiley-Blackwell 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 impacts of hot, dry, and compound hot‐dry extremes are significant for societies, economies, and ecosystems worldwide. Such events therefore need to be assessed in the light of anthropogenic climate change so that suitable adaptation measures can be implemented by governments and stakeholders. Here we show a comprehensive analysis of hot, dry, and compound hot‐dry extremes over global land regions using 25 Coupled Model Intercomparison Project Phase 6 models and four future emissions scenarios from 1950 to 2100. Hot, dry, and compound hot‐dry extremes are projected to increase over large parts of the globe by the end of the 21st century. Hot and compound hot‐dry extremes show the most widespread increases and dry extreme changes are sensitive to the index used. Many regional changes depend on the strength of greenhouse‐gas forcing, which highlights the potential to limit the changes with strong mitigation efforts. Plain Language Summary: Heatwaves, drought and their joint occurrences can negatively impact populations, economies, and natural systems worldwide. It is therefore of paramount importance that governments and stakeholders assess the risk from such events and adapt accordingly. In this study we use 25 climate models and four emission scenarios from 1950 to 2100 to assess how hot, dry, and compound hot‐dry extremes are expected to change in the future when compared to current climate conditions. We find that such extremes are projected to increase by the end of the 21st century over large parts of global land areas under the highest‐emission, no‐policy, climate change scenario. Hot and compound hot‐dry extremes show the most widespread increases, whereas dry extreme changes are sensitive and more regionally limited depending on the method by which they are computed. Most of the regional changes in hot, dry, and compound hot‐dry extremes can be reduced with strong climate change mitigation efforts to limit future green‐house gas emissions. Key Points: Hot extremes are projected to increase in frequency and intensity over almost all land areas by the end of the 21st centuryDrought changes depend on measure but increase robustly over central and northern South America, the Mediterranean, and southern AfricaCompound hot and dry extremes are sensitive to the drought measure but projected to increase in most regions globally [ABSTRACT FROM AUTHOR]

Copyright of Ecology & Evolution (20457758) is the property of Wiley-Blackwell 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 interaction of the northern Nazca and southwestern Caribbean oceanic plates with northwestern South America (NWSA) and the collision of the Panama‐Choco arc (PCA) have significant implications on the evolution of the northern Andes. Based on a quantitative kinematic reconstruction of the Caribbean and Farallon/Farallon‐derived plates, we reconstructed the subducting geometries beneath NWSA and the PCA accretion to the continent. The persistent northeastward migration of the Caribbean plate relative to NWSA in Cenozoic time caused the continuous northward advance of the Farallon‐Caribbean plate boundary, which in turn resulted in its progressive concave trench bending against NWSA. The increasing complexity during the Paleogene included the onset of Caribbean shallow subduction, the PCA approaching the continent, and the forced shallow Farallon subduction that ended in the fragmentation of the Farallon Plate into the Nazca and Cocos plates and the Coiba and Malpelo microplates by the late Oligocene. The convergence tectonics after late Oligocene comprised the accretional process of the PCA to NWSA, which evolved from subduction erosion of the forearc to collisional tectonics by the middle Miocene, as well as changes of convergence angle and slab dip of the Farallon‐derived plates, and the attachment of the Coiba and Malpelo microplates to the Nazca plate around 9 Ma, resulting in a change of convergence directions. During the Pliocene, the Nazca slab broke at 5.5°N, shaping the modern configuration. Overall, the proposed reconstruction is supported by geophysical data and is well correlated with the magmatic and deformation history of the northern Andes. Plain Language Summary: The tectonic reconstruction in convergent triple junctions is a particularly challenging task as the relative motion between plates could define highly changing boundaries. Indeed, the resulting interaction between these convergent plates may induce important changes in the disposition of the trenches, and in turn in the three‐dimensional geometry of the subducting plates. Therefore, these highly dynamic conditions throughout geological time may be accommodated by different phases of plate fragmentation and reorganization. These factors could explain the complex spatial‐temporal distribution of subduction‐related magmatism and the different episodes of deformation in the upper plates. This reasoning is validated in the northwestern corner of South America (SA), where the continent has been converging against the Caribbean and Farallon‐derived oceanic plates since Cretaceous time. Additionally, we study the effects of the collision and accretion of the Panama‐Choco arc with SA. To accomplish that, we review the kinematic history of the Farallon/Nazca and Caribbean oceanic plates relative to stable Guiana Craton (SA) and integrate these results with the magmatic and deformation evolution of the northern Andes, which allow us to propose a model of the geometrical evolution of the subducting slabs. The obtained model is additionally constrained by seismological data and published velocity anomalies. Key Points: The tectonics of convergent triple junctions is complicated by the relative plate motion and interaction of the involved platesWe propose a model for the kinematic and geometric evolution of the Farallon/Nazca and Caribbean plates throughout the CenozoicThe interaction between the Caribbean, Nazca and South American plates is closely related to the deformation history in the Northern Andes [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to comparatively evaluate the learning outcomes achieved by first‐year radiography students educated with either virtual reality (VR) simulation training or physical simulation training. The implementation of VR has been proposed to enhance learning in radiography students and provide a more effective and efficient approach to simulation. However, the learning outcomes achieved with this approach have not been widely investigated. Methods: Through stratified randomisation, 188 radiography students were allocated to one of two matched groups: a VR group (using Virtual Medical Coaching's Radiography simulation) and a physical simulation group (using Philips' X‐ray equipment). Both groups were taught 31 radiography views over one 25‐week semester. Both groups were assessed in an Objective Structured Clinical Examination (OSCE), using actors as patients in a physical X‐ray environment. Assessment was conducted by assigning objective count scores for five assessment criteria. Results: The VR group achieved shorter OSCE duration and fewer errors in moving equipment and patient positioning: these results were statistically significant (P < 0.00). There was no significant difference in the frequency of errors in radiographic exposure setting between the VR and the physical simulation group. The current findings concur with the limited number of published studies concerning VR simulation in radiography. Conclusions: The results of this study demonstrated superior effectiveness and efficiency in the VR group. This provides preliminary evidence to introduce VR simulation in the host institution and provide evidence that it may be possible to replace the use of physical simulation across other years of the degree. Further research investigating these possibilities is warranted. [ABSTRACT FROM AUTHOR]

Copyright of People & Nature is the property of Wiley-Blackwell 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.)

Colletotrichum lupini, the causative agent of lupin anthracnose, affects lupin cultivation worldwide. Understanding its population structure and evolutionary potential is crucial to design successful disease management strategies. The objective of this study was to employ population genetics to investigate the diversity, evolutionary dynamics, and molecular basis of the interaction of this notorious lupin pathogen with its host. A collection of globally representative C. lupini isolates was genotyped through triple digest restriction site‐associated DNA sequencing, resulting in a data set of unparalleled resolution. Phylogenetic and structural analysis could distinguish four independent lineages (I–IV). The strong population structure and high overall standardized index of association (r̅d) indicates that C. lupini reproduces clonally. Different morphologies and virulence patterns on white lupin (Lupinus albus) and Andean lupin (Lupinus mutabilis) were observed between and within clonal lineages. Isolates belonging to lineage II were shown to have a minichromosome that was also partly present in lineage III and IV, but not in lineage I isolates. Variation in the presence of this minichromosome could imply a role in host–pathogen interaction. All four lineages were present in the South American Andes region, which is suggested to be the centre of origin of this species. Only members of lineage II have been found outside South America since the 1990s, indicating it as the current pandemic population. As a seedborne pathogen, C. lupini has mainly spread through infected but symptomless seeds, stressing the importance of phytosanitary measures to prevent future outbreaks of strains that are yet confined to South America. [ABSTRACT FROM AUTHOR]

Abstract: Measures of traits are the basis of functional biological diversity. Numerous works consider mean species‐level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait‐based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from −5.83 to −29.75 decimal degrees of latitude and −34.82 to −56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non‐volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. [ABSTRACT FROM AUTHOR]

The global impacts of El Niño on precipitation have been long‐recognized, but more understanding of the mechanisms behind this influence is needed. For instance, previous studies have largely overlooked the potential impacts of El Niño on terrestrial moisture recycling (TMR). We perform a 40‐year forward tracking simulation to derive a global climatology of recycled precipitation and use a composite analysis to investigate how El Niño affects TMR. We identify seven regions where the El Niño impact on TMR is most significant and find that, in these regions, changes in precipitation and TMR are directly related: they increase or decrease together. In addition, we find a marked latitudinal contrast between the Southern Hemisphere, where TMR increases during El Niño, and the Northern Hemisphere and the tropics, where it decreases. Our results indicate that the weakening and strengthening of TMR can be behind precipitation changes caused by El Niño globally. Plain Language Summary: El Niño is recognized as a climate variability phenomenon with significant impacts on precipitation worldwide. However, the mechanisms behind these impacts are not fully understood. Here we use model simulations to argue that one of those mechanisms is the effect of El Niño on terrestrial moisture recycling (TMR), that is, the fraction of precipitation fed by atmospheric moisture originating not in the ocean but on the continents. We show that El Niño significantly affects TMR globally, especially in seven regions of South America, Africa, North America, Europe, and Asia. In these regions, precipitation and TMR increase or decrease together. We find a contrast between the South and North of the planet: during El Niño, TMR increases in the Southern Hemisphere while decreasing in the Northern Hemisphere and the tropics. Overall, our results indicate that TMR weakening or strengthening are previously overlooked mechanisms behind precipitation changes caused by El Niño globally. Key Points: El Niño exerts significant effects on terrestrial moisture recycling worldwideEl Niño's impacts on terrestrial moisture recycling are most significant in seven regions worldwidePrecipitation and terrestrial moisture recycling increase or decrease together due to El Niño [ABSTRACT FROM AUTHOR]

Copyright of Functional Ecology is the property of Wiley-Blackwell 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.)

Since the mid‐20th century, the so‐called Great Acceleration (sensu Steffen et al., 2007, https://doi.org/10.1579/0044-7447(2007)36[614:TAAHNO]2.0.CO;2) has amplified processes of ecosystem degradation, extinction of biological species, displacement of local peoples, losses of languages, and cultural diversity. These losses are still underperceived by the academic community, and by a global society that is disconnected from biocultural diversity. To reconnect society with biocultural diversity, we integrate temporal and spatial dimensions of seasonal cycles, by combining two conceptual frameworks: ecological calendars and the "3Hs" model of the biocultural ethic (sensu Rozzi, 2012, https://doi.org/10.5840/enviroethics20123414). The latter values the vital links between human and other‐than‐human co‐inhabitants, their life habits (e.g., cultural practices of humans or life cycles of other‐than‐human species), and the structure and processes of their shared habitats. This integration enhances an understanding of links between cultural practices and the life cycles of biocultural keystone species. As a synthesis, we use the term biocultural calendars to emphasize their co‐constitutive nature that result from interactions between dynamic biophysical and cultural processes embedded in specific ecosystems and cultures. These calendars link astronomical, biological, and cultural seasonal cycles that sustain life and enhance the integration of Indigenous and scientific knowledge to confront challenges of climate change faced from local to global scales. To illustrate this integration, we examine cultural practices and socio‐environmental changes across four contrasting ethnolinguistic communities in southwestern South America, from southern to northern Chile along a marked climatic gradient to show the broad application of the concept of biocultural calendars. Plain Language Summary: We combine ecological calendars and the biocultural ethic. The first refers to natural or seasonal calendars and focuses on the temporal scale of life cycles and other ecological phenomena observed at a given place. The second emphasizes the vital links among human and non‐human co‐inhabitants, their habits (e.g., cultural practices of humans or life cycles of other‐than‐human species) in shared habitats (the "3Hs" of the biocultural ethic). Close observation of biological and cultural diversity, and their interrelationships (in short, biocultural diversity), synchronizes cultural practices with natural processes at specific places. This synchrony is particularly relevant in the context of climate change because by being locally attuned, communities enhance their capacity to adapt their activities to the variability of temperature, rainfall, and other climatic events. In this article we use the term biocultural calendars to more closely understand the links between different life habits in contrasting habitats and annual seasons. In this way, biocultural calendars provide an understanding of biological and cultural heterogeneity in different seasons and regions of the world that can help us adapt to a rapidly changing world. Key Points: Biocultural calendars are co‐constitutively generated through interactions between dynamic biophysical and cultural processesThe biocultural ethic's 3Hs model values the vital links among human and other‐than‐human co‐inhabitants, their habits, and shared habitatsBiocultural calendars are based on seasonal cycles of keystone species that are part of communities of co‐inhabitants [ABSTRACT FROM AUTHOR]

Livestock production in drylands requires consideration of the ecological applications of ecohydrological redistribution of water. Intensive cattle trampling and the associated increase of surface runoff are common concerns for rangeland productivity and sustainability. Here, we highlight a regional livestock production system in which cattle trails and trampling surrounding an artificial impoundment are purposely managed to enhance redistribution and availability of water for cattle drinking. Based on literature synthesis and field measurements, we first describe cattle production systems and surface water redistribution in the Dry Chaco rangelands of South America, and then develop a conceptual framework to synthesize the ecohydrological impacts of livestock production on these ecosystems. Critical to this framework is the pioshere—a degraded overgrazed and overtrampled area where vegetation has difficulties growing, usually close to the water points. The Dry Chaco rangelands have three key distinctive characteristics associated with the flat sedimentary environment lacking fresh groundwater and the very extensive ranching conditions: (1) cattle drinking water is provided by artificial impoundments filled by runoff, (2) heavy trampling around the impoundment and its adjacent areas generates a piosphere that favors runoff toward the impoundment, and (3) the impoundment, piosphere, and extensive forage areas are hydrologically connected with a network of cattle trails. We propose an ecohydrological framework where cattle transit and trampling alter the natural water circulation of these ecosystems, affecting small fractions of the landscape through increased runoff (compaction in piosphere and trails), surface connectivity (convergence of trails to piosphere to impoundment), and ponding (compaction of the impoundment floor) that operate together making water harvesting and storage possible. These effects have likely generated a positive water feedback on the expansion of livestock in the region with a relatively low impact on forage production. We highlight the role of livestock transit as a geomorphological agent capable of reshaping the hydrology of flat sedimentary rangelands in ways that can be managed positively for sustainable ranching systems. We suggest that the Dry Chaco offers an alternative paradigm for rangelands in which cattle trampling may contribute to sustainable seminatural production systems with implications for other dry and flat rangelands of the world. [ABSTRACT FROM AUTHOR]

Drake Passage is a key region for transport between the surface and interior ocean, but a mechanistic understanding of this exchange remains immature. Here, we present wintertime, submesoscale‐resolving hydrographic transects spanning the southern boundary of the Antarctic Circumpolar Current and the Polar Front (PF). Despite the strong surface wind and buoyancy forcing, a freshwater lens suppresses surface‐interior exchange south of the PF; ventilation is instead localized to the PF. Multiple lines of the analysis suggest submesoscale processes contribute to ventilation at the PF, including small‐scale, O(10 km), frontal structure in water mass properties below the mixed layer and modulation of a surface eddy diffusivity at sub‐50 km scales. These results show that ventilation is sensitive to both submesoscale properties near fronts and non‐local processes, for example, sea‐ice melt, that set stratification and mixed layer properties. This highlights the need for adaptive observing strategies to constrain Southern Ocean heat and carbon budgets. Plain Language Summary: Drake Passage is a region of the Southern Ocean between the southern tip of South America and the Antarctic Peninsula. Due to its relative accessibility as compared to the rest of the polar ocean, it is the most frequently occupied region of the Southern Ocean. Most occupations by ships in Drake Passage acquire measurements at 20–100 km spacing or "mesoscale" resolution. Here, we present data collected by piloted robotic underwater vehicles that sampled across the southern section of Drake Passage with submesoscale, or 1–10 km, resolution in wintertime. These novel observations indicate that while the southernmost region of Drake Passage is strongly stratified in density, the Polar Front (PF), one of the major dynamical features of the Southern Ocean, is more weakly stratified. The reduced stratification at the PF presents a pathway for the localized exchange of water between the surface and interior ocean. In addition, this study finds that the PF is eddy‐suppressing, meaning that the mean flow of the PF can transport oceanic properties away before they can be stirred. These findings have implications for the estimation of carbon fluxes between the atmosphere and the Southern Ocean, a vital part of the climate system. Key Points: High‐resolution hydrographic sections across the Drake Passage provide insight into spatial variability in surface‐interior exchangeWintertime observations suggest ventilation is spatially localized to the Polar Front and influenced by submesoscale processesA mixing length estimate shows modulation at submesoscales and mixing suppression in the upper layers of the Polar Front [ABSTRACT FROM AUTHOR]

Premise: Pilosocereus (Cactaceae) is an important dry forest element in all subregions and transitional zones of the neotropics, with the highest diversity in eastern Brazil. The genus is subdivided into informal taxonomic groups; however, most of these are not supported by recent molecular phylogenetic inferences. This lack of confidence is probably due to the use of an insufficient number of loci and the complexity of cactus diversification. Here, we explored the species relationships in Pilosocereus in more detail, integrating multilocus phylogenetic approaches with the assessment of the ancestral range and the effect of geography on diversification shifts. Methods: We used 28 nuclear, plastid, and mitochondrial loci from 54 plant samples of 31 Pilosocereus species for phylogenetic analyses. We used concatenated and coalescent phylogenetic trees and Bayesian models to estimate the most likely ancestral range and diversification shifts. Results: All Pilosocereus species were clustered in the same branch, except P. bohlei. The phylogenetic relationships were more associated with the geographic distribution than taxonomic affinities among taxa. The genus began diversifying during the Plio‐Pleistocene transition in the Caatinga domain and experienced an increased diversification rate during the Calabrian age. Conclusions: We recovered a well‐supported multispecies coalescent phylogeny. Our results refine the pattern of rapid diversification of Pilosocereus species across neotropical drylands during the Pleistocene and highlight the need for taxonomic rearrangements in the genus. We recovered a pulse of diversification during the Pleistocene that was likely driven by multiple dispersal and vicariance events within and among the Caatinga, Cerrado, and Atlantic Forest domains. [ABSTRACT FROM AUTHOR]

This study investigates lateral variations in density contrast across the 660‐km discontinuity, which is critical for understanding mantle convection and composition. We produce a global map of density jump, with values ranging from 3.8% to 9.3%, at the mineralogical phase boundary by applying inversions of amplitude variations with offset to underside S reflections. Our observations reveal a global average velocity jump of 4.1% and a density jump of 5.3%, favoring a pyrolitic bulk composition. Near major subduction zones, most notably the western Pacific and South America, we identify reduced density jumps in regions of depressed 660‐km discontinuity, consistent with basalt fractions greater than 30% in a mechanically mixed mantle. The causal association between density jump and compositional changes is further supported by a moderate correlation between lateral variations in density jump and those of water content anomalies. Plain Language Summary: The Earth's mantle is subdivided by a solid‐to‐solid phase change of the mineral olivine near 660 km depth with sharp increases in seismic velocity and density. The physical properties of this phase boundary directly impact our understanding of mass and heat transfer from the Earth's deep mantle to the surface. In this study, we analyze an up‐to‐date data set of bottom‐side reflections, also known as SS precursors, to estimate global variations in density jump at the base of the upper mantle. We find reduced density jumps near regions where oceanic lithospheres are being recycled into the deep mantle. Lateral variations in density contrast show a moderate correlation with the estimated water content in the mantle transition zone (400–700 km depth). Key Points: We use an amplitude‐versus‐offset inversion of SS precursors to constrain density properties of the 660‐km discontinuityWe map global variations in density jump across the 660‐km discontinuityLateral variations in density jump reflect compositional variations and are correlated with transition zone water distribution [ABSTRACT FROM AUTHOR]

We describe the model performance of a new global coupled climate model configuration, CM4‐MG2. Beginning with the Geophysical Fluid Dynamics Laboratory's fourth‐generation physical climate model (CM4.0), we incorporate a two‐moment Morrison‐Gettelman bulk stratiform microphysics scheme with prognostic precipitation (MG2), and a mineral dust and temperature‐dependent cloud ice nucleation scheme. We then conduct and analyze a set of fully coupled atmosphere‐ocean‐land‐sea ice simulations, following Coupled Model Intercomparison Project Phase 6 protocols. CM4‐MG2 generally captures CM4.0's baseline simulation characteristics, but with several improvements, including better marine stratocumulus clouds off the west coasts of Africa and North and South America, a reduced bias toward "double" Intertropical Convergence Zones south of the equator, and a stronger Madden‐Julian Oscillation (MJO). Some degraded features are also identified, including excessive Arctic sea ice extent and a stronger‐than‐observed El Nin∼ $\tilde{\mathrm{n}}$o‐Southern Oscillation. Compared to CM4.0, the climate sensitivity is reduced by about 10% in CM4‐MG2. Plain Language Summary: A sophisticated cloud microphysical scheme, along with a mineral dust and temperature‐dependent ice nucleation scheme, have been implemented in a new configuration of the Geophysical Fluid Dynamics Laboratory's most recent climate model (CM4.0). This microphysical scheme predicts both mass and number concentrations of cloud drops, ice crystals, rain, and snow, and treats aerosol‐cloud interactions more consistently. The ice nucleation on mineral dust aerosol in large‐scale clouds is represented more realistically. Centennial‐scale global coupled atmosphere‐ocean‐land‐sea ice simulations from this new configuration compare favorably with observations—with improved subtropical stratocumulus clouds and better tropical intraseasonal variability (i.e., the 30‐ to 90‐day Madden‐Julian Oscillation). The new configuration also reduces the magnitude of future global warming in response to anthropogenic emissions. Key Points: The performance of two‐moment microphysics with prognostic precipitation and an ice nucleation scheme in CM4.0: CM4‐MG2, is documentedThe overall performance of CM4‐MG2 is comparable to or better than CM4.0, based on a set of Model Intercomparison Project Phase 6 Diagnosis, Evaluation, and Characterization of Klima and historical simulationsNotable improvements include enhanced coastal stratocumulus and a stronger Madden‐Julian Oscillation. CM4‐MG2 has a lower climate sensitivity than CM4.0 [ABSTRACT FROM AUTHOR]

Copyright of Ecology & Evolution (20457758) is the property of Wiley-Blackwell 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.)

Summary: The biogeography of neotropical fungi remains poorly understood. Here, we reconstruct the origins and diversification of neotropical lineages in one of the largest clades of ectomycorrhizal fungi in the globally widespread family Russulaceae.We inferred a supertree of 3285 operational taxonomic units, representing worldwide internal transcribed spacer sequences. We reconstructed biogeographic history and diversification and identified lineages in the Neotropics and adjacent Patagonia.The ectomycorrhizal Russulaceae have a tropical African origin. The oldest lineages in tropical South America, most with African sister groups, date to the mid‐Eocene, possibly coinciding with a boreotropical migration corridor. There were several transatlantic dispersal events from Africa more recently. Andean and Central American lineages mostly have north‐temperate origins and are associated with North Andean uplift and the general north–south biotic interchange across the Panama isthmus, respectively. Patagonian lineages have Australasian affinities. Diversification rates in tropical South America and other tropical areas are lower than in temperate areas.Neotropical Russulaceae have multiple biogeographic origins since the mid‐Eocene involving dispersal and co‐migration. Discontinuous distributions of host plants may explain low diversification rates of tropical lowland ectomycorrhizal fungi. Deeply diverging neotropical fungal lineages need to be better documented. [ABSTRACT FROM AUTHOR]

Despite strong historical biogeographical links between benthic faunal assemblages of the Magellan region of South America and the Antarctic Peninsula, very few studies have documented contemporary movement and gene flow in or out of the Southern Ocean, especially across the Antarctic Polar Front (APF). In fact, oceanographic barriers such as the APF and Antarctica's long geologic isolation have substantially separated the continents and facilitated the evolution of endemic marine taxa found within the Antarctic region. The Southern Ocean benthic sea slug complex, Doris "kerguelenensis," are a group of direct‐developing, simultaneous hermaphrodites that lack a dispersive larval stage. To date, there are 59 highly divergent species known within this complex. Here, we provide evidence to show intraspecific genetic connectivity occurs across the APF for multiple species within the D. "kerguelenensis" nudibranch species complex. We addressed questions of genetic connectivity by examining the phylogeographic structure of the three best‐sampled D. "kerguelenensis" species and another three trans‐APF species using the protein coding mtDNA gene, cytochrome oxidase I. We also highlight alternative refugia uses among species with the same life history traits (i.e., benthic and direct developers) and for some species, extremely large distributions are established (e.g., circumpolarity). By improving our sampling of these nudibranchs, we gain better insight into the population structure and connectivity of the Antarctic region. This work also demonstrates how difficult it is to make generalizations across Antarctic marine species, even among ecologically‐similar, closely related species. [ABSTRACT FROM AUTHOR]

We review recent research about the development of creativity in South America focusing on studies of individual differences in creativity and educational and developmental studies of children and adolescents' creativity. Most South American researchers are influenced by mainstream psychometric approaches, although computational and cultural approaches are also considered. Two main areas of inquiry are: (a) the relationship between creativity and other constructs, and (b) the structural and cultural inhibitors of creativity in school. Studies conducted beyond the school shed light on the role resilience has in fostering creativity. The lack of studies testing interventions aimed at promoting creativity is concerning. There is also a surprising lack of observational studies related to the pedagogy of creativity. Last but not least, there is a need to advance research on other factors, in addition to the educational ones, that may play a role in fostering creativity in South America. [ABSTRACT FROM AUTHOR]

Global biodiversity is organised into biogeographic regions that comprise distinct biotas. The contemporary factors maintaining differences in species composition between regions are poorly understood. Given evidence that populations with sufficient genetic variation can adapt to fill new habitats, it is surprising that more homogenisation of species assemblages across regions has not occurred. Theory suggests that expansion across biogeographic regions could be limited by reduced adaptive capacity due to demographic variation along environmental gradients, but this possibility has not been empirically explored. Using three independently curated data sets describing continental patterns of mammalian demography and population genetics, we show that populations near biogeographic boundaries have lower effective population sizes and genetic diversity, and are more genetically differentiated. These patterns are consistent with reduced adaptive capacity in areas where one biogeographic region transitions into the next. That these patterns are replicated across mammals suggests they are stable and generalisable in their contribution to long‐term limits on biodiversity homogenisation. Understanding the contemporary processes that maintain compositional differences among regional biotas is crucial for our understanding of the current and future organisation of global biodiversity. [ABSTRACT FROM AUTHOR]

Semipalmated sandpipers are Arctic breeding shorebirds that migrate to South America during the non‐breeding season. Little work has been done to understand the daily movements, foraging habits and metabolic state of this species on stationary nonbreeding grounds. Our work was conducted at the Banco dos Cajuais Western Hemisphere Shorebird Reserve Network (WHSRN) site in Northeast Brazil. We captured semipalmated sandpipers in February and March 2019 and 2020 and attached nanotags to monitor their daily movements. Blood samples were taken to measure plasma triglycerides (an index of fattening rate). We also conducted behavioral observations on foraging birds. Using tracking data we determined that most semipalmated sandpipers appeared to use sunrise/sunset as an indicator for movement between salina and tidal flat habitats, and a smaller portion used tidal height. We found birds spent similar amounts of time foraging on tidal flats and in salinas, though different foraging modes were used. Plasma triglyceride measures suggest semipalmated sandpipers had not started preparing to migrate when sampled. We successfully tracked semipalmated sandpipers to North America during northward migration in 2020, detecting eight within the United States. Tracking results suggest many stopped elsewhere in South America to fuel for migration, though some may have fueled at the Banco dos Cajuais. By demonstrating substantial use of both natural and altered habitats in the region by migrant semipalmated sandpipers, these data highlight the need for broader conservation measures throughout coastal regions of South America. [ABSTRACT FROM AUTHOR]

The Caribbean plate is an enclosed oceanic basin whose formation and evolution are controversial. In the most commonly accepted model, the Caribbean plate is mainly composed of the Caribbean Large Igneous Province (CLIP) and the buoyant characteristic of this oceanic plateau resisted subduction and allowed an eastward migration to its present position north of South America. In this study, we integrate a broad range of geophysical and geomorphological data to define structural elements and present‐day tectonics of the Caribbean plate and the surrounding region. We present a Bouguer gravity anomaly map and a new crustal thickness map that documents large areas of normal‐thickness oceanic crust within the Venezuela and Colombia basins of the Caribbean plate. Selected cross sections of seismicity and P‐wave anomalies from a seismic tomographic model depict the present‐day geometry of subducting oceanic plates within the Caribbean region. We observe that rather than resisting subduction, as expected for the thick crust of a buoyant large igneous province, the subduction of the Caribbean plate can be traced to a depth of 600 km beneath NW South America. This, together with the crustal thickness map, implies that a significant area of the Caribbean plate, including the subducted portion, is composed of normal‐thickness oceanic crust. As proposed by the Pacific origin model, the Caribbean plate likely migrated eastward from the Pacific Ocean as an oceanic plate mostly with normal‐thickness crust and limited portions of the crust thickened by hot spot volcanism (CLIP). Plain Language Summary: The Caribbean plate and northern South America are studied using topography and multiple geophysical data sets, including gravity, magnetics, crustal thickness, seismicity, and seismic images of the upper mantle. These data sets were used to analyze crustal properties as well as the past and present interaction of tectonic plates in this region. Our results show large areas of ocean crust with normal thickness within the Caribbean plate. Seismicity in the circum‐Caribbean subduction zones rarely exceeds 200 km in depth, whereas seismic imaging shows subducting slabs reach a depth of 600 km or more. This implies that subduction has been long‐lived at these active margins. These results also show that the Caribbean plate is subducting beneath NW South America, something that would not be expected for the thick crust of a buoyant large igneous province. As proposed by the Pacific origin model, the Caribbean plate migrated eastward from the Pacific Ocean as an oceanic plate mostly with normal‐thickness crust and limited portions of the crust thickened by hot spot volcanism. Key Points: A new crustal thickness map and gravity maps reveal large areas of normal‐thickness oceanic crust within the Caribbean plateP‐wave seismic tomography images show that the subducted Caribbean plate reaches 660 km depth, but slab seismicity terminates at 200 kmCombined seismicity, gravity, and magnetic maps reveal the active tectonics of the circum‐Caribbean accretionary and magmatic boundary [ABSTRACT FROM AUTHOR]

The Madden Julian Oscillation (MJO) is the main source of intraseasonal variability in the tropics. MJO modulates rainfall in remote areas in the Southern Hemisphere by exciting tropical and extratropical wave trains. We use newly released reanalysis data to analyze how the Quasi‐Biennial Oscillation (QBO) can influence the MJO's effects over the Southern Hemisphere, focusing on precipitation anomalies over South America. The anomalies in the intensity of the South Atlantic Convergence Zone (SACZ) and precipitation over Southeastern South America during MJO phases 1 and 4 are intensified during the easterly QBO. The extratropical wave train excited by the anomalous convection over the maritime continent during MJO phase 4 is affected by the QBO, with a stronger, better‐defined pattern during westerly QBO. The conclusions are supported by a perturbation experiment of a case study, conducted using a high‐top atmospheric global climate model where the QBO and MJO are controlled. Plain Language Summary: Subseasonal to seasonal prediction remains challenging in the current forecast models. Previous studies have shown that the Quasi‐Biennial Oscillation (QBO) can influence the intensity and development of the Madden Julian Oscillation (MJO). Here, the consequences of this modulation on the remote effects of the MJO in the Southern Hemisphere are analyzed using reanalysis and perturbation experiments in an atmospheric global climate model. The rainfall anomalies related to the MJO in South America are more intense and widespread during easterly QBO over the South Atlantic Convergence Zone and southern Brazil than during westerly QBO. Thus, the inclusion of the state of the QBO in the estimate of the expected rainfall associated with the MJO is crucial to improve forecasts in the region. Key Points: The Quasi‐Biennial Oscillation (QBO) modulates the impacts of the Madden Julian Oscillation (MJO) in the Southern HemisphereMJO‐related rainfall anomalies in the South Atlantic Convergence Zone are intensified during easterly QBOEThe extratropical wave train forced by the anomalous convection in MJO phase 4 is intensified under QBOW [ABSTRACT FROM AUTHOR]

The El Niño‐Southern Oscillation (ENSO) strongly influences phytoplankton in the tropical Pacific, with El Niño conditions suppressing productivity in the equatorial Pacific (EP) and placing nutritional stresses on marine ecosystems. The Geophysical Fluid Dynamics Laboratory's (GFDL) Earth System Model version 4.1 (ESM4.1) captures observed ENSO‐chlorophyll patterns (r = 0.57) much better than GFDL's previous ESM2M (r = 0.23). Most notably, the observed post‐El Niño "chlorophyll rebound" is substantially improved in ESM4.1 (r = 0.52). We find that an anomalous increase in iron propagation from western Pacific (WP) subsurface to the cold tongue via the equatorial undercurrent (EUC) and subsequent post‐El Niño surfacing, unresolved in ESM2M, is the primary driver of chlorophyll rebound. We also find that this chlorophyll rebound is augmented by high post‐El Niño dust‐iron deposition anomalies in the eastern EP. This post‐El Niño chlorophyll rebound provides a previously unrecognized source of marine ecosystem resilience independent from the La Niña that sometimes follows. Plain Language Summary: In the tropical Pacific, year‐to‐year changes in chlorophyll, a proxy for the phytoplankton base of ocean food webs, is dominated by the El Niño–Southern Oscillation. El Niño, triggered by westerly wind anomalies and subsequent redistributions of upper ocean heat content, can sharply reduce the regional supply of nutrients limiting phytoplankton growth. A new Earth System Model captures not only the onset and extent of chlorophyll anomalies during El Niño events, but also a pronounced post‐El Niño "chlorophyll rebound" that produces positive equatorial Pacific chlorophyll anomalies in the summer following El Niño events. This post‐El Niño chlorophyll rebound is primarily driven by positive iron anomalies propagated from the subsurface western Pacific to the surface eastern Pacific cold tongue via the Equatorial Undercurrent. High post‐El Niño dust deposition anomalies arising from dry land conditions in Central and South America augment the post‐El Niño chlorophyll rebound. This post‐El Niño chlorophyll rebound provides a key source of resilience to marine ecosystems in the equatorial Pacific. Key Points: The observed post‐El Niño chlorophyll anomaly, "chlorophyll rebound," in the equatorial Pacific is successfully simulated in GFDL‐ESM4.1This rebound is primarily driven by surfacing high iron anomalies propagated from western Pacific via Equatorial UndercurrentHigh dust‐iron deposition anomalies arising from dry land conditions augment the post‐El Niño chlorophyll rebound [ABSTRACT FROM AUTHOR]

The D″ region consists of many different structures on many length‐scales and here we test whether an inhomogeneous scattering region could potentially explain two of these seismic observables, namely PKP precursors, which are generated by scattering near the core‐mantle boundary, and reflections of a seismic discontinuity in the lowermost mantle. The focus of this study is on modeling PKP precursors and lower mantle reflections. Testing different heterogeneity models with a range of correlation lengths and velocity perturbations for D″, we find that some of our models can produce both waves. Comparing our synthetic seismograms to real data for precursors in adjacent locations beneath the mid‐Atlantic near South America we find the best fitting model with correlation length of 10 km and velocity perturbation of 5% with a gradual increase of scattering defined by a taper from 200 to 400 km above the core‐mantle boundary. Plain Language Summary: The lowest 300 km of the Earth's mantle (called D″ layer) consists of many different structures that range from small‐scale features such as scatterers to large‐scale structures such as large regions with lower seismic velocity than the surrounding mantle. The structures are visible with a range of seismic waves but many studies are restricted to only one wavetype. In this study, we focus on two seismic waves that are usually associated with different structures. First, PKP precursors that are P waves scattered at small‐scale features in the lowermost mantle and second the PdP wave that reflects off the D″ boundary which is associated with a sharp velocity change. We compute synthetic seismic data assuming a scattering region in D″, testing models of different scatterer sizes and strength and find that some of these models can in fact produce both wavetypes. Additionally, we find a best fitting model by comparing the synthetics with real earthquake data imaging the lower mantle beneath the mid‐Atlantic near South America. We thereby show that perhaps some structures in the lowermost mantle, previously interpreted as different features, are in fact related. This may help to improve our knowledge of the geodynamical processes in the lower mantle. Key Points: We show that PKP precursors and PdP reflections can be produced by the same heterogeneity structure in the lowermost mantle (D″ layer)Our heterogeneity models consist of scatterers of different correlation lengths (10, 50 km) and velocity perturbations (1%, 3%, 5%)Best fitting model for PKP precursors that also generates PdP reflections has a correlation length of 10 km and velocity changes of 5% [ABSTRACT FROM AUTHOR]