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The presence of cryptic species can hinder effective conservation planning and implementation, as has been the case for speciose groups of freshwater fishes that are difficult to differentiate due to conserved morphologies. The West Texas shiner Notropis megalops and the Texas shiner Notropis amabilis are a cryptic pair of leuciscids (minnows) that co‐occur in spring‐fed tributaries of the Rio Grande in Texas and Mexico. Both N. megalops and N. amabilis are listed as Species of Greatest Conservation Need by the Texas Parks and Wildlife Department. Notropis amabilis is widespread and listed as apparently secure by Texas Parks and Wildlife Department whereas N. megalops has a very limited distribution and has not been ranked by Texas Parks and Wildlife Department because of data deficiency. Morphological differences between these species have been described; however, proper identification in situ remains problematic. Furthermore, given their range of overlap there is potential for hybridization, and limited genetic data have been collected comparing the species. Therefore, reduced representation genomic and mitochondrial sequencing data were used to reassess the distinctness of the species, screen for hybridization, and characterize their relative frequencies throughout their range of overlap. Genomic analyses recovered two distinct genetic groups corresponding to the species (F'CT = 0.89) with no evidence of admixture or introgression. The species were found to co‐occur at three sampling locations, two in the Devils River and one in the Pecos, but not in equal frequencies. Overall, these results provide data and tools for further research on N. megalops needed for accurate conservation policies and management practices. [ABSTRACT FROM AUTHOR]

Tomato production on a global scale is under persistent pressure due to the devastating impact of Phthorimaea absoluta Meyrick (Lepidoptera: Gelechiidae), the South American tomato leaf miner. To combat this devastating pest, we explored the potential of plant-mediated RNA interference (RNAi) as a novel strategy for its management. Using transgenic techniques, we developed RNAi constructs (p35S::dsAChE1, p35S::dsSEC23) targeting crucial genes, AChE1 and SEC23, in P. absoluta. These genes play pivotal roles in insect physiology and development. The transformation of tomato cultivar Rio Grande was carried out with these RNAi constructs using Agrobacterium tumefaciens. The results demonstrated a significant reduction in transcript levels of both AChE1 and SEC23 in P. absoluta. Silencing AChE1 resulted in substantial mortality rates, reduced larval weight gain, and deformities, highlighting its pivotal role in insect survival. SEC23 gene silencing also induced mortality and influenced insect physiology. Furthermore, we explored the susceptibility of AChE1 to organophosphate insecticides, revealing its relevance in insecticide susceptibility. These findings support the potential of AChE1 and SEC23 as valuable targets for RNAi-based control of P. absoluta for the first time, providing multifaceted insights into insect physiology and insecticide susceptibility, thereby offering valuable insights for the development of effective strategies to mitigate the impact of this destructive pest.

The lower Rio Grande and Pecos River of the southwest United States have been heavily modified by human activities, profoundly impacting the integrity of their aquatic wildlife. In this context, we focused our study on the population genomics of the Rio Grande Cooter (Pseudemys gorzugi), a freshwater turtle of increasing conservation concern, residing in these two rivers and their tributaries. The genetic data revealed two distinct populations: one in the Pecos and Black Rivers of New Mexico and another in the Rio Grande and Devils River of Texas, with admixed individuals identified at the confluence of the Rio Grande and Pecos River. In addition to having a smaller geographic range, we found lower observed heterozygosity, reduced nucleotide diversity, and a smaller effective population size (N e) in New Mexico population. Our results depict a significant isolation-by-distance pattern across their distribution, with migration being notably infrequent at river confluences. These findings are pivotal for future conservation and restoration strategies, emphasizing the need to recognize the unique needs of each population. [ABSTRACT FROM AUTHOR]

Limiting resources are often unevenly distributed among competing consumers, as larger, more aggressive, fast growing, early emerging, or rapidly reproducing species disproportionately exploit food or habitat. In such cases, asymmetric competition can occur (i.e., when limited resources are divided up unequally among individuals or species), resulting in stronger negative effects for some species and comparatively weaker effects for others. We hypothesize that the accessibility of food web pathways influences asymmetric competition among stream fishes. To test this hypothesis, we studied the interactions of invasive brown trout (Salmo trutta) with native Rio Grande sucker (Catostomus plebeius or Pantosteus plebeius) and Rio Grande chub (Gila pandora) in mountain streams of New Mexico, USA, from 2020 to 2021. Our study found support for the hypothesis that the accessibility of food web pathways drives asymmetric competition in mountain stream fishes, as native chub and sucker grew at slower rates than invasive brown trout across all observed body sizes. Our conclusion is evidenced by (1) strong diet overlap driven by benthic macroinvertebrates that (2) were important in fueling the growth of native fishes but were also (3) disproportionately exploited by trout. Because trout fed on small aquatic invertebrates, large crayfish, other fish, and inputs of terrestrial prey, they could incorporate energy from differing food web pathways, whereas native fishes were mostly limited to small benthic prey (and chubs fed on terrestrial arthropods). As trout, chub, and sucker competed for small benthic prey, trout could also incorporate other sources of food, whereas chub and sucker had fewer options. Although two or more species may compete for one resource, their rates of growth and production are also dependent on, and fueled by, other food web pathways. Our work demonstrates that such food web pathways help explain differences in growth and production between invasive and native fishes. Our findings show that tracking energy flows through the different food web pathways provides a useful and intuitive means of describing the important sources of food (i.e., the trophic basis of production) that fuel growth and production and sheds light on the processes that drive asymmetric competition. [ABSTRACT FROM AUTHOR]

This essay contributes to literature on the intersections of white settler colonialisms, racial capitalism, and U.S.-Mexico borderlands history by tracing the web of spatial, temporal, and legal power relations that produced El Paso, Texas' seemingly legitimate possession of stolen Mexican territory known as "El Chamizal" in the El Paso-Cd. Juárez borderlands. This land theft became the Chamizal Dispute: an international land and boundary conflict between the U.S. and Mexico caused by the meandering Río Grande that defines the "fixed" international border between El Paso, Texas and Cd. Juárez, Chihuahua. In the 1860s, multiple shifts in the Rio Grande "relocated" El Chamizal north of this river/boundary. Soon thereafter, and despite Mexico's sustained claim to and jurisdiction over this land, recently arrived Anglo American settlers incorporated El Chamizal into the nascent City of El Paso. In 1964, the U.S. and Mexico finally agreed to resolve this conflict by virtue of the landmark Chamizal Treaty, which ceded 630-acres of El Paso to Cd. Juárez as El Chamizal. Contrary to what dominant state accounts and the mainstream historical literature on this settlement would have us believe, however, this ceded land includes only a fraction of the original contested terrain. El Chamizal therefore remains a stolen tract of land nestled within the heart of El Paso. Drawing on oral histories, court testimonies and affidavits, and an array of binational records, this essay demonstrates that this ongoing theft is not a finite or complete project. Rather, the process hinges on a fragile web of spatial, white settler temporal, and legal practices of concealment/denial anchored to a colonial rumor that refuses to open this region to the mystery and wonder of the Río Grande's "wayward life, beautiful experiment in how to live." [ABSTRACT FROM AUTHOR]

Abstract Limiting resources are often unevenly distributed among competing consumers, as larger, more aggressive, fast growing, early emerging, or rapidly reproducing species disproportionately exploit food or habitat. In such cases, asymmetric competition can occur (i.e., when limited resources are divided up unequally among individuals or species), resulting in stronger negative effects for some species and comparatively weaker effects for others. We hypothesize that the accessibility of food web pathways influences asymmetric competition among stream fishes. To test this hypothesis, we studied the interactions of invasive brown trout (Salmo trutta) with native Rio Grande sucker (Catostomus plebeius or Pantosteus plebeius) and Rio Grande chub (Gila pandora) in mountain streams of New Mexico, USA, from 2020 to 2021. Our study found support for the hypothesis that the accessibility of food web pathways drives asymmetric competition in mountain stream fishes, as native chub and sucker grew at slower rates than invasive brown trout across all observed body sizes. Our conclusion is evidenced by (1) strong diet overlap driven by benthic macroinvertebrates that (2) were important in fueling the growth of native fishes but were also (3) disproportionately exploited by trout. Because trout fed on small aquatic invertebrates, large crayfish, other fish, and inputs of terrestrial prey, they could incorporate energy from differing food web pathways, whereas native fishes were mostly limited to small benthic prey (and chubs fed on terrestrial arthropods). As trout, chub, and sucker competed for small benthic prey, trout could also incorporate other sources of food, whereas chub and sucker had fewer options. Although two or more species may compete for one resource, their rates of growth and production are also dependent on, and fueled by, other food web pathways. Our work demonstrates that such food web pathways help explain differences in growth and production between invasive and native fishes. Our findings show that tracking energy flows through the different food web pathways provides a useful and intuitive means of describing the important sources of food (i.e., the trophic basis of production) that fuel growth and production and sheds light on the processes that drive asymmetric competition.

Este trabalho tem por objetivo realizar um estudo comparativo da legislação sobre o patrimônio cultural das cidades do Rio Grande, Jaguarão e Pelotas, localizadas no Rio Grande do Sul. A cidade do Rio Grande foi o berço da colonização portuguesa no extremo sul do Brasil, tendo como marco a instalação de um forte em 19 de janeiro de 1737. Por conta de sua posição estratégica, ficou sendo o centro comercial da província, principalmente a partir de meados do século XIX, com um processo de industrialização que permitiu a constituição de um patrimônio arquitetônico diversificado. A partir da década de 1980 o município passou a legislar sobre a proteção de seu patrimônio cultural, movimento similar ao ocorrido em outras cidades da região sul do estado, como Pelotas e Jaguarão. O estudo comparativo destas legislações, permitirá constituir um panorama de como se apresenta a política de preservação nestes municípios.

Freshwater fishes are among the most imperiled organismal groups in the world and efforts to conserve many species are hindered by a lack of basic information pertaining to the diet habits and trophic relationships of various fish species. The purpose of this study was to fill knowledge gaps pertaining to the feeding habits and trophic ecology of Rio Grande chub (Gila pandora) and Rio Grande sucker (Catostomus plebeius) to aid in their conservation and protection. Specifically, we conducted (1) a literature review of the feeding habits of Rio Grande chub and Rio Grande sucker to summarize existing information and (2) a field study to quantify the describe the feeding habits and trophic relationships of these chub and sucker species. Review of previously published literature revealed no empirical diet studies for Rio Grande chub and only two studies for Rio Grande sucker. Statements about the diet habits of each fish species were vague and repeated through published gray and peer-reviewed literature. Findings from our field study provided far greater detail about each species diet composition and diet overlap. Rio Grande chub primarily fed on aquatic macroinvertebrates whereas Rio Grande sucker primarily consumed stream periphyton, and to a lesser degree, benthic macroinvertebrates. Both species selected aquatic Coleoptera larvae relative to prey availability. Our findings provide a clearer understanding of the feeding habits and trophic relationships and can be used to guide restoration or enhancement efforts to help maintain and improve the viability of their populations. [ABSTRACT FROM AUTHOR]

Understanding the intermittent hydraulic connectivity between ephemeral streams and alluvial aquifers is a key challenge for managing water resources in arid environments. The lower Rio Grande flows for short, discontinuous periods during the irrigation season through the Mesilla Basin in southeastern New Mexico and southwestern Texas. Hydraulic connections between the Rio Grande and the Rio Grande alluvial aquifer in the Mesilla Basin vary spatially and temporally and are not well understood. Self-potential (SP) monitoring and time-lapse electric resistivity tomography (ERT) were therefore performed along linear cross-sections spanning the riverbed and flood plain for more than 4 months to monitor the transient hydraulic connection between the river and the alluvial aquifer by measuring time-lapse changes in the electric potential field in the riverbed and flood plain. The monitoring period began on 21 May 2022, when the riverbed was completely dry, continued through the irrigation season while streamflow was provided by reservoir releases from upstream dams, and ended on 4 October 2022, when the riverbed was again dry. SP monitoring data show (1) a background condition in the dry riverbed consisting of (a) a positive electric potential anomaly with a maximum amplitude of about +100 mV attributed predominantly to a subsurface vertical salt concentration gradient and (b) diurnal electric potential fluctuations with amplitudes of 40,000–90,000 mV attributed to near-surface heat conduction driven by weather variability, in addition to (2) a streaming potential anomaly during the irrigation season with a maximum amplitude of about −3500 mV whose transient behavior clearly exhibited a change from the background anomaly to depict exclusively losing streamflow conditions that persisted through the irrigation season. Time-lapse ERT monitoring results depict rapid infiltration of streamflow into the subsurface and imply the river and Rio Grande alluvial aquifer established a full hydraulic connection within a few hours after streamflow arrival at the monitoring site. SP monitoring data show an apparent transition from hydraulic connection to disconnection at the end of the irrigation season and indicate that the transitional phase between connection and disconnection may last substantially longer than the transition from disconnection to connection. The combination of SP and ERT monitoring demonstrated herein shows the potential for broader applications of time-lapse monitoring of hydraulic intermittency and near-surface heat fluxes in different rivers. [ABSTRACT FROM AUTHOR]

Invasive predators pose a critical threat to native taxa. Body size plays an important role in mediating the interactions of predator and prey. For piscivorous fishes, increased predator body size can be accompanied by the selection of increasingly larger prey or may reflect a mix of small and large prey. Knowledge of such interactions helps determine how predation affects population vital rates. Here, we assessed the predatory effects of invasive Brown Trout (Salmo trutta) on populations of native Rio Grande Sucker (Catostomus plebeius) and Rio Grande Chub (Gila pandora) in streams of the Jemez River watershed (New Mexico, USA). Trout diets were sampled every two weeks during the 2020 growing season. Predator and prey body lengths were measured to examine relationships to better understand patterns of piscivory and quantify the threat Brown Trout pose to populations of Rio Grande Chub and Rio Grande Sucker. Across all streams and sampling dates, 7% of Brown Trout diets contained fish. Predator–prey length relationships reflected a ‘wedge’ pattern, indicating that Brown Trout consumed an increasing range of prey body sizes as they grew larger. Rio Grande Sucker and Rio Grande Chub comprised 46% of consumed fishes. The findings demonstrated that Rio Grande Sucker and Rio Grande Chub experience constant predation over the growing season by Brown Trout. Moreover, our study provides evidence that these invasive predators pose a threat to the viability of Rio Grande Chub and Rio Grande Sucker populations. Conservation efforts to protect these chub and sucker populations must account for and directly address predation by invasive Brown Trout.

A simple and improved Agrobacterium-mediated transformation protocol of tomato (Solanum lycopersicum) cultivar Rio Grande was developed to inspect the potential of producing transgenic tomatoes. In this study, regeneration and transformation efficiency as assessed in response to the seedling age, explant type, co-infection, co-cultivation duration, selection pressure (kanamycin), and the optimal concentration of plant growth regulators (PGR) 6-benzylaminopurine (BAP), gibberellic acid (GA3), and indolebutyric acid (IBA) in a Murashige and Skoog (MS) basal medium. To accomplish this goal, 2- to 4-wk-old tomato explant cotyledons, hypocotyl, and cotyledonary nodes were excised and transformed with the EHA105 Agrobacterium tumefaciens strain harboring pBIN19 binary vector containing uidA reporter gene and nptII as a selectable marker. Results revealed that 14-d-old cotyledonary nodes and leaves inoculated for 15 min with A. tumefaciens strain EHA105 following 48-h co-cultivation were optimal for the highest percent transformation efficiency 27.31. Antibiotic kanamycin (Kan) at 25 mg L−1 in the regeneration selection medium was found to be effective. MS medium containing optimal concentrations of 1.5 mg L−1 of BAP, 0.2 mg L−1 GA3, and IBA 1.5 mg L−1 showed a significant level of percent regeneration, shoot elongation, and rooting efficiency of transformed plantlets. Molecular analysis of T0 transgenic tomato plants showed integration and a higher relative expression level of the uidA gene. The optimized A. tumefaciens–mediated transformation method for tomato cultivar Rio Grande showed the highest percent transformation efficiency (TE) and regeneration efficiency (RE) and is likely to give consistent results with different tomato cultivars. [ABSTRACT FROM AUTHOR]

Study Region: Rio Grande Headwaters Study Focus: In the western US wildfires are increasing in duration and frequency, insect inducted forest mortality is widespread, and both wildfires and forest mortality are exacerbated by drought. These forest disturbances have hydrologic implications that are not always evident in the post-disturbance water budget – especially at the watershed outlet. In this study we evaluate two snow dominated paired catchment systems in the forested Rio Grande headwaters – where each impacted site was severely burned by the 2013 West Fork Complex (WFC) fire, and all sites (including control sites) were severely impacted by spruce beetle induced forest mortality from approximately 2005 to 2010. A combination of observed runoff, reanalysis precipitation, and remotely sensed evapotranspiration and vegetation metrics are used to evaluate the post-fire surface water budget (runoff and evapotranspiration) in paired catchments. New hydrological insights for the region: Significant changes in post-fire surface water budget partitioning are not detectable, which is likely the result of decreased evapotranspiration due to insect-induced vegetation change in all study catchments prior to the fire. Our findings highlight the importance of considering overlapping disturbances, especially in paired catchment studies, and in alpine and subalpine forest regions like the Rio Grande headwaters that are increasingly prone to drought, insect mortality and wildfire. Our results also illustrate that insect induced forest mortality has significant implications for post-fire hydrology studies that rely on control-impact or before-and-after comparisons.

Invasive predators pose a critical threat to native taxa. Body size plays an important role in mediating the interactions of predator and prey. For piscivorous fishes, increased predator body size can be accompanied by the selection of increasingly larger prey or may reflect a mix of small and large prey. Knowledge of such interactions helps determine how predation affects population vital rates. Here, we assessed the predatory effects of invasive Brown Trout (Salmo trutta) on populations of native Rio Grande Sucker (Catostomus plebeius) and Rio Grande Chub (Gila pandora) in streams of the Jemez River watershed (New Mexico, USA). Trout diets were sampled every two weeks during the 2020 growing season. Predator and prey body lengths were measured to examine relationships to better understand patterns of piscivory and quantify the threat Brown Trout pose to populations of Rio Grande Chub and Rio Grande Sucker. Across all streams and sampling dates, 7% of Brown Trout diets contained fish. Predator–prey length relationships reflected a 'wedge' pattern, indicating that Brown Trout consumed an increasing range of prey body sizes as they grew larger. Rio Grande Sucker and Rio Grande Chub comprised 46% of consumed fishes. The findings demonstrated that Rio Grande Sucker and Rio Grande Chub experience constant predation over the growing season by Brown Trout. Moreover, our study provides evidence that these invasive predators pose a threat to the viability of Rio Grande Chub and Rio Grande Sucker populations. Conservation efforts to protect these chub and sucker populations must account for and directly address predation by invasive Brown Trout. [ABSTRACT FROM AUTHOR]

Biological monitoring is important for assessing the ecological condition of surface waters. However, there are challenges in determining what constitutes reference conditions, what assemblages should be used as indicators, and how assemblage data should be converted into quantitative indicator scores. In this study, we developed and applied biological condition gradient (BCG) modeling to fish and macroinvertebrate data previously collected from large, sandy bottom southwestern USA rivers. Such rivers are particularly vulnerable to altered flow regimes resulting from dams, water withdrawals and climate change. We found that sensitive ubiquitous taxa for both fish and macroinvertebrates had been replaced by more tolerant taxa, but that the condition assessment ratings based on fish and macroinvertebrate assemblages differed. We conclude that the BCG models based on both macroinvertebrate and fish assemblage condition were useful for classifying the condition of southwestern USA sandy bottom rivers. However, our fish BCG model was slightly more sensitive than the macroinvertebrate model to anthropogenic disturbance, presumably because we had historical fish data, and because fish may be more sensitive to dams and altered flow regimes than are macroinvertebrates. [ABSTRACT FROM AUTHOR]

We present a comprehensive analysis of water availability under plausible future climate conditions in a heavily irrigated agricultural watershed located in the middle section of the Rio Grande Basin in the United States Desert Southwest. Future managed streamflow scenarios (through year 2099) were selected from among 97 scenarios developed based on downscaled, bias‐corrected global climate model outputs to evaluate future inflows to the principal surface water storage reservoirs, possible future reservoir releases, and groundwater pumping to sustain irrigated agriculture. The streamflow projections describe a wide range of dry and wet conditions compared to the average historical flows in the river, indicating significant uncertainty in future water availability in the Rio Grande Basin. We applied the Soil and Water Assessment Tool to illustrate the impact of climate futures on different components of the water budget at a watershed scale. Results indicate declining reliability of reservoir storage to meet the water demand of irrigated agriculture. The impact of declining surface water can be offset by increasing the pressure on the already‐strained groundwater resources. However, the region should be prepared to use slightly saline (total dissolved solids [TDS] > 1,000 mg/L) and moderately saline groundwater (TDS > 3,000 mg/L) as fresh groundwater in the regional aquifer is depleted within the 21st Century under hotter and drier conditions and status quo agricultural land and water management practices. [ABSTRACT FROM AUTHOR]

The objective of this work was to realize a preliminary stydy the diversity, composition and structure of the aquatic and semiaquatic Heteroptera assemblage of Río Grande basin (Jujuy, Argentina) along a temporal and spatial gradient. For the first time, a list of the taxa inhabiting the area is presented, which includes 11 genera belonging to eight families. The sites corresponding to the lower basin exhibited higher diversity, and the genus Rhagovelia was the most abundant in both hydrological seasons. In contrast, the upper basin exhibited a low diversity, and its assemblage was dominated by Ectemnostega, both in the wet and dry season. Significant differences in the diversity of aquatic and semiaquatic bugs at the temporal level were not found in this basin. [ABSTRACT FROM AUTHOR]

The Rio Grande/Bravo is an arid river basin shared by the United States and Mexico, the fifth-longest river in North America, and home to more than 10.4 million people. By crossing landscapes and political boundaries, the Rio Grande/Bravo brings together cultures, societies, ecosystems, and economies, thereby forming a complex social-ecological system. The Rio Grande/Bravo supplies water for the human activities that take place within its territory. While there have been efforts to implement environmental flows (flows necessary to sustain riparian and aquatic ecosystems and human activities), a systematic and whole-basin analysis of these efforts that conceptualizes the Rio Grande/Bravo as a single, complex social-ecological system is missing. Our objective is to address this research and policy gap and shed light on challenges, opportunities, and success stories for implementing environmental flows in the Rio Grande/Bravo. We introduce the physical characteristics of the basin and summarize the environmental flows studies already done. We also describe its water governance framework and argue it is a distributed and nested governance system across multiple political jurisdictions and spatial scales. We describe the environmental flows legal framework and argue that the authority over different aspects of environmental flows is divided across different agencies and institutions. We discuss the prioritization of agricultural use within the governance structure without significant provisions for environmental flows. We introduce success stories for implementing environmental flows that include leasing of water rights or voluntary releases for environmental flow purposes, municipal ordinances to secure water for environmental flows, nongovernmental organizations representing the environment in decision-making processes, and acquiring water rights for environmental flows, among others initiatives. We conclude that environmental flows are possible and have been implemented but their implementation has not been systematic and permanent. There is an emerging whole-basin thinking among scientists, managers, and citizens that is helping find common-ground solutions to implementing environmental flows in the Rio Grande/Bravo basin. [ABSTRACT FROM AUTHOR]

Flora de Rio Grande. Ejemplares nuevos o menos conocidos en el Herbario de la Reserva Anchieta. Nota del Editor Web: el idioma del artículo es el latín.

The present geographical topic approaches the reflection about the spatiality and its relation to the religion in Rio Grande. This understanding about the devotional spatiality is intermediated by the symbolic that is present in the performance of the rio‐grandinos religious practitioners, and aims the reflection about the sacred events, in research on Geography Cultural. The study also presents as an aim to propose the use of these events as an empirical contribution in the analysis on Geography. In this sense, the observation still consists in the geographic dialogue, ruling, in the theoretical attributions of Eric Dardel (1899‐1967) and Paul Claval (1932‐ ), among others. Then, the research is justified on the geographic science by sharpen the debate about the affinity of man with the environment, emphasizing the culture in the form of interpreting the interactions of the “Entity” with the space and with the religious symbolic in the places. [ABSTRACT FROM AUTHOR]

Background The blue catfish is of great value in aquaculture and recreational fisheries. The F1 hybrids of female channel catfish (Ictalurus punctatus) × male blue catfish (Ictalurusfurcatus) have been the primary driver of US catfish production in recent years because of superior growth, survival, and carcass yield. The channel–blue hybrid also provides an excellent model to investigate molecular mechanisms of environment-dependent heterosis. However, transcriptome and methylome studies suffered from low alignment rates to the channel catfish genome due to divergence, and the genome resources for blue catfish are not publicly available. Results The blue catfish genome assembly is 841.86 Mbp in length with excellent continuity (8.6 Mbp contig N50, 28.2 Mbp scaffold N50) and completeness (98.6% Eukaryota and 97.0% Actinopterygii BUSCO). A total of 30,971 protein-coding genes were predicted, of which 21,781 were supported by RNA sequencing evidence. Phylogenomic analyses revealed that it diverged from channel catfish approximately 9 million years ago with 15.7 million fixed nucleotide differences. The within-species single-nucleotide polymorphism (SNP) density is 0.32% between the most aquaculturally important blue catfish strains (D&B and Rio Grande). Gene family analysis discovered significant expansion of immune-related families in the blue catfish lineage, which may contribute to disease resistance in blue catfish. Conclusions We reported the first high-quality, chromosome-level assembly of the blue catfish genome, which provides the necessary genomic tool kit for transcriptome and methylome analysis, SNP discovery and marker-assisted selection, gene editing and genome engineering, and reproductive enhancement of the blue catfish and hybrid catfish. [ABSTRACT FROM AUTHOR]

Along the U.S.‐Mexico border, an aggressive non‐native grass, giant cane (Arundo donax), grows in dense, nearly impenetrable stands along hundreds of kilometers of the Rio Grande/Bravo (RGB). Between 2008 and 2018, a diverse, multisector binational‐team repeatedly treated giant cane with prescribed fire and herbicide along 90 km of this binational river to restore aquatic and riparian habitat and native plant community composition. The large geographic scale, binational management response, treatment methods used, and development of a long‐term monitoring program to quantify treatment impacts on the RGB's riparian plant community underscore the unique aspects of this effort. Results of this decade‐long management experiment indicate that (i) the combination of a primary treatment of giant cane (using prescribed fire followed 4–6 weeks later by herbicide treatment of regrowth) and a secondary treatment (spot treatment of regrowth one or more years following primary treatment) was effective in reducing the extent and distribution of giant cane at relatively low cost, (ii) giant cane re‐establishment following treatment is often not rapid, nor dramatic; and (iii) as revealed by analysis of riparian vegetation monitoring data, eradication of dense stands of giant cane have fostered significant and long‐term reduction in giant cane cover and recovery of native woody riparian plant taxa. Important caveats to the long‐term viability of managing giant cane hinge on better understanding the consequences of herbicide use, securing funding to cover the cost of re‐treatment, and continuing river flow management focused on promoting the recovery of native riparian obligate plants over non‐natives. [ABSTRACT FROM AUTHOR]

Los ?Agarici tropicales? son casi lo mismo que los europeos. Lo que llama la atención es el gran número de formas pequeñas que en Europa faltan. Estos organismos sólo pueden ser clasificados cuando aún están frescos. Por eso, a excepción de Spegazzini, pocos hubo que los recogieran. Distribuí las secciones según el tamaño, constante entre ciertos límites. Por lo demás, la clave analítica mediante los esporos hace más fácil la clasificación. La Lepiota es conocida por los esporos blancos, el velo y por tener las lamelas separadas del pie. Si en el hongo hay un velo y los esporos son blancos, más las lamelas están unidas al pie, entonces se tiene el género Schtazeria de pocas especies. Nota del editor web: el artículo está escrito en latín.

This paper discusses the strategies of communication, alliance, and solidarity established by the Mbya Guarani Y'yrembé (Beira-mar) and Pará Rokê (Portal do Mar) communities and the Kaingang Goj Tahn (Mar Azul) community in the development of policies to combat the Covid-19 pandemic in the municipality of Rio Grande. Through participant observation throughout the year 2020, I report how the actions protagonized by the caciques, the Municipal Council of Indigenous Peoples, in partnership with the Coordinator of Public Policies for Indigenous Peoples, the non-indigenous population, and higher education institutions ensured policies aimed at health, food security, cultural translation, and the maintenance of territories in the scenario of containing the advance of the new coronavirus. [ABSTRACT FROM AUTHOR]

The concept of coalescent communities has been widely used by North American archaeologists as a framework for understanding cultural responses to social upheaval. In this article we explore how the concept of coalescence helps us understand the processes that led to the emergence of aggregated settlements in the Albuquerque district of the central Rio Grande Valley around the turn of the fourteenth century. We argue that such communities emerged as strategic local responses to disruptive social and demographic trends on a macroregional scale. Specifically, we use NAA and petrographic sourcing of Western Pueblo- and Rio Grande-style glaze-painted pottery in conjunction with settlement data from the site of Tijeras Pueblo (LA581) to explore how the amalgamation of immigrant and autochthonous people, technology, knowledge, and ritual creatively and radically transformed local and regional practices of community and identity formation. [ABSTRACT FROM AUTHOR]

In 2000, Tim Church published an excellent examination of the secondarily deposited obsidian in Rio Grande Quaternary alluvium for a relatively small section of the Rio Grande in southern New Mexico. Here, the goal is to complement Church's study to include six secondary deposits of a portion of the Rio Grande hydrological basin nearly 400 km in length, coupled with a comparison to 11 archaeological sites on or near the river basin. Additionally, the compositional and metric data on obsidian sources from the Jemez Lineament sources have also improved since 2000, providing useful data on nodule dimension as well as compositional data at the primary sources. By recording both nodule sizes against source provenance at these points along the Rio Grande, scholars can compare the results of nearby archaeological contexts and the source obsidian available at various points along the Rio Grande. It is often difficult to determine whether the raw material used to produce a chipped stone tool was originally procured at the source or in secondary contexts. That, however, can never be achieved anywhere in the world without firm secondary depositional data. This issue is the focus of this study. [ABSTRACT FROM AUTHOR]

Este trabajo propone un nuevo aporte al estudio de los conflictos de la frontera hispanoportuguesa en la región de Río Grande en la segunda mitad del siglo xviii. Para ello, se analiza la expedición comandada desde Buenos Aires por Juan José de Vértiz en 1773, desde una perspectiva renovada por la incorporación de nuevas fuentes y por los avances historiográficos recientes. Esto permite visibilizar los límites de la acción imperial en aquel espacio fronterizo disputado, donde era muy difícil materializar con una línea divisoria el poder y la soberanía pretendidos por ambas coronas. Se concluye que la frontera que la expedición estableció provisoriamente no era el resultado de la geografía, la diplomacia o la guerra, sino de las limitaciones que los imperios encontraban para proyectarse en áreas como esa.

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Few studies have evaluated the effects of large wildfires on downstream non-salmonid fish assemblages. Using multi-year (2009–2015) data from fish assemblage surveys and high-frequency water quality monitoring, we analyzed within-site responses of a cypriniform-dominated fish assemblage at two sites located > 20 km downstream of a 633 km2 wildfire in 2011 in the Rio Grande watershed in New Mexico, USA. Season had a weak influence on fish assemblage (fish) catch rate, richness, and evenness at the upstream site, but it had a strong negative influence (during spring/winter) on fish catch rate and richness at the downstream site. Fish species richness and evenness at both sites were not strongly affected by the wildfire, despite numerous post-fire sags in dissolved oxygen (including short-lived hypoxia < 2 mg L−1and anoxia—0 mg L−1) during subsequent monsoon seasons. Although fish catch rate was negatively impacted by the wildfire at the upstream site, it was unaffected at the downstream site. Fish catch rate, richness, and evenness at the upstream site were suppressed following a major flood event that occurred 26 months post-fire, but the downstream fish assemblage was resistant to the flood disturbance. Our study provided a rare opportunity to evaluate how aridland riverine fishes respond to disturbance from wildfire and subsequent flooding. Larger and more severe wildfires are occurring due to climate warming, and responses of water quality and fish community assemblages require study and assessment. [ABSTRACT FROM AUTHOR]

Despite tensions between Mexico and the United States, the countries continue to develop cooperative strategies to manage shared water resources under the Treaty on the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande. These strategies include agreements in 2012 and 2017 to advance sustainable management of the Colorado. Unfortunately, these advances have not been mirrored by improvements for the Rio Grande. We consider Minutes 319 and 323, examine the potential for a minute to create similar benefits for the Rio Grande, and offer recommendations to improve stakeholder engagement, binational cooperation and sustainability in that basin. [ABSTRACT FROM AUTHOR]

Questions: Predicting the influence of climate change on riparian plant communities improves management strategies. The sensitivity of riparian vegetation to climate and other abiotic factors depends on interactions between properties of the ecosystem, like flood regime, and plant characteristics. To explore these interactions, we addressed three questions: (a) does the composition and diversity of riparian vegetation vary with the flood regime; (b) do abiotic correlates of vegetation, including climate and groundwater, differ between sites that flood compared to locations that did not experience floods; and (c) which plant functional groups account for differential plant community sensitivity to abiotic factors between flood regimes? Location: Middle Rio Grande Valley, New Mexico. Methods: We used long-term observations of plant community composition, groundwater depth, precipitation and interpolated temperature from 24 sites spanning 210 km of the Rio Grande riparian cottonwood-willow forest to explore the relative importance of climate and hydrologic correlates of riparian vegetation diversity and composition. Results: Riparian plant diversity was higher at sites flooding compared to non-flooding sites. Plant diversity positively tracked shallower groundwater depth at flooding sites, but was best predicted by intra-annual groundwater variability at non-flooding sites. Plant community composition correlated with groundwater depth and air temperature at all sites, but at non-flooding sites, also with intra-annual groundwater variability and precipitation. Relationships between native plant cover and potential environmental drivers diverged strongly between the two flood regimes; non-native plant cover had only weak relationships with most environmental predictors. Conclusions: The current flood regime of a site determined the climate and hydrologic factors that best predicted riparian plant community composition and diversity. Relationships between plant diversity or total cover and groundwater, temperature, precipitation, or groundwater variability can change in strength or direction depending on a site's flood history, highlighting the importance of flood regime to predicting the sensitivity of riparian woodlands to future environmental change. [ABSTRACT FROM AUTHOR]

Editor-in-Chief's Note: The Texas Water Journal invited The Honorable Jayne Harkins, P.E., U.S. Commissioner for the International Boundary and Water Commission to share her thoughts on water deliveries from Mexico to the Rio Grande. The opinion expressed in the resulting commentary is the opinion of Commissioner Harkins and not the opinion of the Texas Water Journal or the Texas Water Resources Institute. Citation: Harkins J. 2020. Commentrary: Fact vs. fiction on Rio Grande deliveries. Texas Water Journal. 11(1):130-132. Available from: https://doi.org/10.21423/twj.v11i1.7120.

O artigo pretende estabelecer uma relação entre o presente e o presente tendo como objeto o Clube Caixeiral de Rio Grande, RS, a partir do reconhecimento visual no contexto em que está inserido, e compreender como isso influiu em frequentadores que por ali passaram. Essa análise pretende demonstrar o quanto os sentidos da memória podem exercer uma situação favorável diante das fontes, sejam elas materiais (suportes) ou imateriais (lembranças), a partir de pontos de referência estabelecidos pela memória dos locais.

The bitter observation of child actor Bobby Driscoll, who won a special Academy Award for his performance in The Window (1949), sums up the attitude of many actors that have found themselves built up and feted, only to be cast aside by the studio system’s ruthless prioritising of the bottom line. The annals of Hollywood history are littered with tales of child actors financially exploited by guardians; worn down by unrelenting schedules; terrorised by directors and moguls; sinking into addiction and, in the case of some such as Driscoll, succumbing to early deaths. Invariably, the stories of the casualties make for juicy reading—even if the particular star rarely profits from book sales—but accounts of those that emerged from the system relatively unscathed, or that voluntarily checked out of it, are rarer and generally elicit less interest from the public.

The Rio Grande/Bravo is an arid river basin shared by the United States and Mexico, the fifth-longest river in North America, and home to more than 10.4 million people. By crossing landscapes and political boundaries, the Rio Grande/Bravo brings together cultures, societies, ecosystems, and economies, thereby forming a complex social-ecological system. The Rio Grande/Bravo supplies water for the human activities that take place within its territory. While there have been efforts to implement environmental flows (flows necessary to sustain riparian and aquatic ecosystems and human activities), a systematic and whole-basin analysis of these efforts that conceptualizes the Rio Grande/Bravo as a single, complex social-ecological system is missing. Our objective is to address this research and policy gap and shed light on challenges, opportunities, and success stories for implementing environmental flows in the Rio Grande/Bravo. We introduce the physical characteristics of the basin and summarize the environmental flows studies already done. We also describe its water governance framework and argue it is a distributed and nested governance system across multiple political jurisdictions and spatial scales. We describe the environmental flows legal framework and argue that the authority over different aspects of environmental flows is divided across different agencies and institutions. We discuss the prioritization of agricultural use within the governance structure without significant provisions for environmental flows. We introduce success stories for implementing environmental flows that include leasing of water rights or voluntary releases for environmental flow purposes, municipal ordinances to secure water for environmental flows, nongovernmental organizations representing the environment in decision-making processes, and acquiring water rights for environmental flows, among others initiatives. We conclude that environmental flows are possible and have been implemented but their implementation has not been systematic and permanent. There is an emerging whole-basin thinking among scientists, managers, and citizens that is helping find common-ground solutions to implementing environmental flows in the Rio Grande/Bravo basin.

The Rio Grande is still gorged & only beasts of burden come to cross & bathe & even then they're waiting for motherships The Tejano dips his toes Wet mud [...]

This article aims to identify the relations between the regional dynamics of the charqueadas economy and the development of soccer practice in the cities of Pelotas and Rio Grande (RS). It is intended to highlight the influence of neighboring countries, industrial capital and aristocracy in the process of forming a local economy and the very diffusion of football practices. This sport has known different routes of introduction in Brazil that are explained, in part, by the economic relations established with other countries. Rio Grande do Sul presents some combinations that elucidate the pioneering spread of football, especially in the southern region of the state. The cities of Pelotas and Rio Grande formed the largest economic and demographic pole of southern Brazil between the mid-19th and early 20th centuries, establishing trade relations with the countries of the River Plate, attracting European immigrants and English capital. The city of Pelotas, located between the Camacho gaúcha and the port of Rio Grande, became the capital of the charque aristocracy that financed the emergence of new spaces of sociability such as theaters, cafes and clubs. Football understood as a modern European practice is gradually incorporated by the Pelotan elite. In this same sense, it is the charque economy that makes the Rio Grande port the largest in southern Brazil, attracting foreign investments in port activities, manufacturing and infrastructure. The English colony of the city met in clubs and practiced the football, sharing it also with the German workers. The port activity in Rio Grande, the charqueadas in the city of Pelotas and the platinum influence are factors that contributed to the formation of the first football clubs and regional leagues in the late nineteenth and early twentieth centuries. Thus, in order to understand the relations between the geographic and historical dynamics of the cities of Pelotas and Rio Grande with the dispersion of the sport of Breton, the text will resort methodologically to the bibliographical and documentary revision.

The Grande and Barrancas Rivers watersheds conform the upper basin of the Colorado River. They provide discharge from snow precipitated in the high mountain peaks. Morphometric and functional characteristics analysis of a basin is elementary in hydrology and modeling approach. The aim of this work was to analyze and interpret the morphometric parameters and derived indices of the upper basin of the Colorado River, Argentina. Parameters quantification and analysis were based on a digital elevation model and Geographic Information Systems. Length of the Grande River is three times greater than Barrancas River ones, with a drainage area that follows the same relationship. Gravelius coefficients evidenced similarities in watershed shapes, both rectangled-oblongued. Both watersheds have a half of their area between 1500 and 2500 m.a.s.l., with predominant slopes between 0 and 15o. In both cases, 54% of slopes are orientated to south direction, meaning predominantly shady. Barrancas River has a greater difference between the source and the mouth, having a smaller drained area. Results from this study offers an important source of base information to further research and modeling spatio-temporal dynamics of flow of River basin.

Abstract Transboundary river basins experience complex coordination challenges during droughts. The multiscale nature of drought creates potential for spillovers when upstream adaptation decisions have cascading impacts on downstream regions. This paper advances the institutional analysis and development (IAD) framework to examine drought adaptation decision‐making in a multijurisdictional context. We integrate concepts of risk management into the IAD framework to characterize drought across its natural and human dimensions. A global analysis identifies regions where severe droughts combine with institutional fragmentation to require coordinated adaptation. We apply the risk‐based IAD framework to examine drought adaptation in the Rio Bravo/Grande—an archetypical transboundary river shared by the United States and Mexico and by multiple states within each country. The analysis draws on primary data and a questionnaire with 50 water managers in four distinct, yet interlinked, “institutional catchments,” which vary in terms of their drought characteristics, socioeconomic attributes, and governance arrangements. The results highlight the heterogeneity of droughts and uneven distribution of their impacts due to the interplay of drought hazards and institutional fragmentation. Transboundary water sharing agreements influence the types and sequence of interactions between upstream and downstream jurisdictions, which we describe as spillovers that involve both conflict and cooperation. Interdependent jurisdictions often draw on informal decision‐making venues (e.g., data sharing, operational decisions) due to the higher transaction costs and uncertainty associated with courts and planning processes, yet existing coordination and conflict resolution venues have proven insufficient for severe, sustained droughts. Observatories will be needed to measure and manage the cascading risks of drought.

Coastal and continental wetlands in semi-arid environments near urban areas denote a valuable socioenvironmental heritage. These areas are exposed to stresses generated by urban expansion, especially if that expansion is rapid. This paper focuses on the physical changes in wetlands caused by such urban expansion and on the factors that increase this problem. The study case is focused on the city of Río Grande. This coastal city is on the steppe of Tierra del Fuego, Argentina, and its expansion started in 1972 following industrial promotion policies. Wetland identification, classification, and mapping from the multispectral analysis of satellite images is used to consider three periods related to changes in national policies for industrial development. The space-temporal analysis indicates a strong link between applied policies and the dynamic of urban growth and natural land occupation. Urban expansion involved the loss of one-third of the wetland and this includes fragmented units. Urban settlements on wetlands demand large amounts of gravel and soil to raise the land level and this represents a significant environmental externality to consider. Finally, informal settlements and a lack of planning are factors than increase wetland loss. [ABSTRACT FROM AUTHOR]

Copyright of Sociedade & Natureza is the property of Sociedade & Natureza 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.)

This paper leverages a multidisciplinary approach to investigate the origin of the initial farming population of the Northern Rio Grande. In doing so, I evaluate two contrasting hypotheses concerning the source areas of these migrants. The first hypothesis, which I call the "Southern Origin" hypothesis, represents the predominant narrative and proposes that the most likely source of the early Tewa Basin population was agricultural communities of the Middle Rio Grande to the south. The second hypothesis, which I call the "Northern Origin" hypothesis, posits that the most likely source was late Pueblo I and early Pueblo II agricultural communities within the Navajo Reservoir/Fruitland District in northwestern New Mexico. Although evidence from paleodemography, archaeology, and linguistics is most consistent with the Northern Origin hypothesis, it also reveals complexities that suggest that alternative scenarios for Northern Rio Grande initial farming population growth need to be considered. [ABSTRACT FROM AUTHOR]

Seasonal streamflow forecast bias, changes in climate, snowpack, and land cover, and the effects of these changes on relations between basin‐wide snowpack, SNOw TELemetry (SNOTEL) station snowpack, and seasonal streamflow were evaluated in the headwaters of the Rio Grande, Colorado. Results indicate that shifts in the seasonality of precipitation and changing climatology are consistent with periods of overprediction and underprediction in streamflow forecasts. Multiple linear regression of SNOTEL data, postcedent precipitation, and land‐cover changes explained 2%–18% more variability in streamflow prediction than using SNOTEL station data alone. Simulated basin‐wide snowpack from a physically based model had significant negative trends in snow water equivalent (−4.33 mm/yr) and snow‐covered area (−0.05%/yr) during the melt period April–June. Simulated streamflow from a precipitation‐runoff model increased an average 5% when the effects of bark beetle‐induced tree mortality were compared to a baseline simulation with static vegetation. The effects of a 2013 wildfire increased simulated seasonal streamflow an average 35% for 1–4 years postfire. The combined effects of climate and land‐cover changes on snowpack‐streamflow relations highlight the difficulty in seasonal streamflow forecasting, which has important implications for water‐resource management. Research Impact Statement: Changing relations between snow, precipitation, and seasonal runoff were evaluated in the Rio Grande Headwaters basin using statistical and physical modeling techniques. [ABSTRACT FROM AUTHOR]

Aims Determining the ecological consequences of interactions between slow changes in long-term climate means and amplified variability in climate is an important research frontier in plant ecology. We combined the recent approach of climate sensitivity functions with a revised hydrological 'bucket model' to improve predictions on how plant species will respond to changes in the mean and variance of groundwater resources. Methods We leveraged spatiotemporal variation in long-term datasets of riparian vegetation cover and groundwater levels to build the first groundwater sensitivity functions for common plant species of dryland riparian corridors. Our results demonstrate the value of this approach to identifying which plant species will thrive (or fail) in an increasingly variable climate layered with declining groundwater stores. Important Findings Riparian plant species differed in sensitivity to both the mean and variance in groundwater levels. Rio Grande cottonwood (Populus deltoides ssp. wislizenii) cover was predicted to decline with greater inter-annual groundwater variance, while coyote willow (Salix exigua) and other native wetland species were predicted to benefit from greater year-to-year variance. No non-native species were sensitive to groundwater variance, but patterns for Russian olive (Elaeagnus angustifolia) predict declines under deeper mean groundwater tables. Warm air temperatures modulated groundwater sensitivity for cottonwood, which was more sensitive to variability in groundwater in years/sites with warmer maximum temperatures than in cool sites/periods. Cottonwood cover declined most with greater intra-annual coefficients of variation (CV) in groundwater, but was not significantly correlated with inter-annual CV, perhaps due to the short time series (16 years) relative to cottonwood lifespan. In contrast, non-native tamarisk (Tamarix chinensis) cover increased with both intra- and inter-annual CV in groundwater. Altogether, our results predict that changes in groundwater variability and mean will affect riparian plant communities through the differential sensitivities of individual plant species to mean versus variance in groundwater stores. [ABSTRACT FROM AUTHOR]

All buildings have an impact on us, whether seeing and navigating through and around them for the first time or frequently. Their materiality interacts with us and the streetscape, contributing to our internal and external, sometimes received narrative. David Goldblatt, Emeritus Professor of Philosophy at Denison University in Ohio, explains this complex interrelationship and contemplates the effect new materiality might have on this symbiosis. [ABSTRACT FROM AUTHOR]

Although freshwater systems comprise a small portion of land surface, they play a pivotal role in landscape carbon (C) cycling. Carbon processing by heterotrophic bacteria is critical, contributing to ecosystem production and dissolved organic carbon (DOC) processing. Riverine bacterial C metabolism is related to a diversity of factors, including (1) physiochemical conditions and inorganic nutrient concentrations and (2) DOC quality and quantity; however, the relative importance of these factors in influencing C metabolism across arid fluvial networks remains equivocal. This study examined C metabolism by heterotrophic bacterioplankton in the Rio Grande drainage, an arid river network in Texas, USA. We examined spatial variation in physicochemical and inorganic nutrient conditions, bacterial C metabolism, and DOC lability across the drainage and assessed whether variation in bacterial C metabolism was more related to physicochemical–inorganic nutrient conditions or DOC quantity and lability. Across the drainage, hydrology and landscape position influenced physicochemical conditions, bacterial abundance, phytoplankton biomass, and bacterial C metabolism and the proportion of variation in bacterial C metabolism explained by physicochemical/inorganic nutrient and DOC quality–quantity gradients was approximately equal. Bacterial abundance and production were associated with greater NH4+ and DOC concentrations and phytoplankton biomass, whereas bacterial respiration and growth efficiency were driven by DOC color and suspended particulate concentrations. Results indicate that aspects of bacterial C metabolism are influenced by different environmental factors related to autochthonous and allochthonous inputs to riverine systems, which has implications for C transformation, sequestration, and transport to the ocean. [ABSTRACT FROM AUTHOR]

The Allende–Piedras Negras (APN) aquifer is located between the states of Texas (United States [U.S.]) and Coahuila (Mexico). The Rio Grande crosses the aquifer, acting as a natural and political divide between the countries. However, it remains unclear whether the APN aquifer can be considered a truly transboundary aquifer flow system, which would potentially require joint management by two different administrative jurisdictions. The main purpose of this study was to evaluate the transboundary nature of this aquifer. This was achieved by developing a detailed hydrogeological model to analyze the direction of volumetric fluxes within the APN aquifer using Visual MODFLOW. The model simulated a spatially averaged cumulative drawdown of 0.76 m for the entire aquifer over an 18‐year modeling period (2000–2017). The flow convergence zone, previously located below the Rio Grande, has shifted to the U.S. side in most locations, driven by higher pumping rates of the wells located near the river. This shift of the convergence zone from one country to the other means that groundwater recharge from one side flows underneath the river to the other side. This qualifies the APN aquifer as a "transboundary groundwater flow system." The procedure followed in this study may be applied to other aquifers that straddle the U.S.–Mexico border and may motivate future modeling studies on other poorly studied transboundary aquifers around the world and thereby enable bi‐national aquifer management. Research Impact Statement: More precipitation falling as rain and briefer snow cover would increase the kinetic energy of rain falling on snow‐free ground, hence may increase surface soil erosion in the Lake Tahoe Basin. [ABSTRACT FROM AUTHOR]

Este trabalho analisa a navegação a vapor no Sul de Minas, no contexto dos diversos projetos de modernização dos transportes formulados no Brasil desde o século XIX. São abordadas as características das companhias, suas realizações e dificuldades, ressaltando-se a subordinação do fluxo dos vapores ao movimento das ferrovias. Conclui-se que a extinção da navegação na região está relacionada, por um lado, com a tendência de concentração dos investimentos numa única modalidade de transporte (ferroviário, depois rodoviário) e, por outro lado, com as consequências de projetos hidroelétricos. As fontes empregadas são relatórios governamentais, jornais, testemunhos de moradores e textos de memorialistas.

La ciudad de Río Grande, provincia de Tierra del Fuego, en el extremo sur de la República Argentina, creció muy aceleradamente en las últimas cuatro décadas a partir de la localización de actividades económicas incentivadas por una ley de promoción, producto de una decisión geopolítica de ocupar el territorio con población argentina. Esto dio lugar a un importante flujo migratorio desde otras provincias. El sector urbano de Margen Sur ha sido el mayor receptor de migrantes pero, dado que lo hicieron en asentamientos, el resultado ha sido una zona donde se concentraron los peores indicadores en la propiedad de la tierra, la cobertura de servicios de infraestructura, el hacinamiento, los hogares con Necesidades Básicas Insatisfechas (NBI), la desocupación, el analfabetismo y las viviendas irrecuperables. En los últimos años, la gestión municipal encaró diversas acciones tendientes a evitar nuevas ocupaciones masivas de tierras y a urbanizar los asentamientos informales generados desde 2006. La situación actual es de una gran incertidumbre sobre el futuro de la ciudad de Río Grande, pero en caso que las migraciones continúen, deberán atenderse algunos desafíos fundamentales y encarar acciones sostenibles en el tiempo.

No século XXl a globalização tem impactado as relações porto-cidade no que se refere à sua dinâmica de crescimento, fato observado sobretudo em muitos centros urbanos ao redor do mundo. Observam-se novas formas de articulação da economia brasileira com o capitalismo internacional e também distintas caracterizações das cidades médias do país. Este trabalho tem por objetivo investigar o crescimento econômico, quanto ao PIB (Produto Interno Bruto), populacional e espacial a partir da expansão urbana de Rio Grande e São José do Norte no período de 1990-2010. Foram utilizadas imagens LANDSAT 5 do Sensor Thematic Mapper (TM). Os dados foram processados nos softwares Spring e ArcGIS. Como procedimentos também foi realizada pesquisa bibliográfica, no IBGE, FEE/RS (Fundação de Economia e Estatística do Rio Grande do Sul), entrevistas e visita aos locais de expansão. Os resultados demonstram, neste período, a associação entre o fenômeno da urbanização e a atividade portuária, com o crescimento de ambas as cidades. Conclui-se que proporcionalmente São José do Norte expandiu-se mais do que Rio Grande e ressalta-se o papel do Estado nesse processo.