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The article focuses on the introduction of civil juries in Argentina's Chaco province within the broader global context of jury systems. It examines historical precedents, comparative analysis with the American civil jury, motivations behind Chaco's adoption of civil juries, and potential implications for jury reform. It offers insights into the evolution of jury systems and their role in promoting fairness and access to justice.

In Chaco, one of the provinces with higher deforestation rate in Argentina, the trajectory of this indicator was not homogenous. Besides, the decision-making of provincial state had different paths to respond to this problem. Thus, this paper tries to answer what the causes that influence in the state fluctuations in the implementation of environmental policies are. Throughout a case study in which I compare four different moments between 2008 and 2019, I argue that the state fluctuations depend on the resolution of the conflict between two coalition (protectionist vs. productivist). State responds favorably to one or another when one of them deploys three strategies together: coordination, institutional and public pressure strategies. [ABSTRACT FROM AUTHOR]

During samplings carried out to evaluate the diversity of calyptrate flies (Diptera: Calyptratae) in northeastern Argentina, Mesembrinella bicolor (Fabricius, 1805) was first detected. This finding represents the second species of Mesembrinellidae from Argentina, after Mesembrinella bellardiana Aldrich, 1922 and the southernmost known record for a species of Mesembrinellidae. A brief diagnosis of both species is included. [ABSTRACT FROM AUTHOR]

In this article we analyze youth political militancy in the province of Chaco - Argentina during the period of recent history known as democratic transition, specifically from 1980 to 1983. We investigate the characteristics of youth groups, their members and the development of their political practices from the beginning of the decade until the advance of the electoral campaign. The results of the investigation, carried out from journalistic sources and oral interviews, allowed us to clarify the characterization of the "juvenile enthusiasm" assigned to the time. We recover aspects that led to the reorganization of political parties and influenced the scene of provincial political opening, stopping at the experience of youth groups. In this way, we incorporate aspects such as tensions with the recent past, relationships with senior leaders, and intergenerational political learning. [ABSTRACT FROM AUTHOR]

The jaguar (Panthera onca) is of great concern throughout its entire range due to the decline of its populations and the loss of its natural habitats, which is why protected areas, like the Defensores del Chaco National Park in Paraguay, play such an important role in the conservation of this feline. However, the dense vegetation of the Chacoan dry forest can make it difficult to conduct studies beyond existing road networks to learn about wild populations. In this study, we propose a method for calculating jaguar density estimations based on a linear distribution of camera trap stations, considering the limitations of this approach given the standard assumptions of capture-recapture models. We obtained an initial density estimate of 1.14 (0.35-3.8) jaguars/100 km², in addition to recording 14 potential jaguar prey species; of which, Dolichotis salinicola, Sylvilagus brasiliensis, and Mazama gouazoubira were the most abundant. [ABSTRACT FROM AUTHOR]

The purpose of this article is to identify the ways in which the Escuela Superior de Niñas nº 2 (located at the Resistencia city, Chaco province, Argentine) and the daily life of the school are represented, based on the written reports of its students about a specific event: the fiftieth anniversary of the school in 1938. The theoretical-methodological support of this research is based on the foucauldian perspectives on discourse analysis and archival theory, which allow us to establish dialogues around the historical and political conjunctures of the time. Considering the conceptions around the school, pedagogical and academic discourse, it was possible to identify that these discourses are supported by discursive formations that provide the basis for different interpretations about the daily school life, the importance of that school for the society from Resistencia and its value for the economic growth of Chaco, in the historical-political conjuncture of the time. [ABSTRACT FROM AUTHOR]

The study of the relationship between executive functions, intellectual abilities, and academic achievement plays an important role in the field of cognitive neuroscience, particularly for their implications in the educational field. Intelligence has been linked to executive functions. In fact, core aspects of intelligence, such as reasoning, problem-solving and planning, are often included in the wide range of frontal lobe functions and over laps with the so-called higher-level executive functions. In addition, executive functioning abilities are associated with skills put in play when participating in learning activities at school. In this sense, different studies have demonstrated that a lower performance on executive function measures typically is associated with a lower performance across different academic areas. The aim of this work was focused on the relationship between intelligence and executive functions, and their ability to predict academic achievement. In the present study, a non-experimental, transversal and descriptive-correlational design was implemented to explore the relationship between intellectual abilities, executive functions, and academic performance in a sample of 37 adolescents (17 girls) aged 13-14 years. The information was collected through the school reports of participants, and their performance on tests BANFE-2 (neuropsychological battery of the executive functions and frontal lobes) and WISC-IV (Wechsler intelligence scale for children 4th Ed.). Also, adolescents were classified into two groups (high- and low performers) based on their performance on the general intelligence score. Participants with IQ scores below the median were assigned to the low-performing group, while participants with IQ scores above the median were assigned to the high-performing group. The data obtained were subjected to descriptive, correlation and regression analyses. Results showed a pattern of positive and significant correlations between executive functions variables (BANFE-2) and intelligence scores (WISC-IV). The 69 % of significant correlations indicated a moderate - strong degree of association (i. e., 49

Fieldwork in two protected areas from northeastern Argentina (P.N. El Impenetrable in Chaco Province, and the P.N. Rio Pilcomayo in Formosa Province) exploring the Heteroptea fauna, resulted in the discovery of a Camarochilus confusus Harris 1930 male that was collected by sweeping the vegetation. The species belongs to the subfamily Pachynominae, representing the first record of the group in the country. Aphelonotus simplus Uhler 1894 (Aphelonotinae), was also collected using light traps, confirming its occurrence in the Chaco ecoregions in Argentina. [ABSTRACT FROM AUTHOR]

This article analyzes the processes of agrarian change associated to the first expansion of the extensive dryland agriculture frontier in middle-western Dry Chaco (northwestern Argentina) during the 1960-1990 period. The singularity of the case in relation to other agrarian spaces of the region is that soybean cultivation was introduced in the 1960s in the farming colonies of that area, constituting one of the first spaces in Argentina where soybean was produced commercially. This experience constituted the precedent in relation to which public organizations and private companies produced knowledge and technology to achieve economically positive results on what until then was a marginal space, based on a crop with no national background in semi-arid spaces. In the 1970s, investors from other sectors of the economy acquired land and imprinted a business model for agriculture in the study area. However, during the 1980s soil degradation became a general problem that slowed the expansion of the previous decade. [ABSTRACT FROM AUTHOR]

The article recovers some reflections on the socio-educational trajectories of a group of indigenous teachers in the province of Chaco, emphasizing schooling and the processes of identification of the subjects. This work is part of a broader investigation focused on systematizing these trajectories considering the processes of articulation / overlap / identity denial of a group of qom teachers in the center of the province. The methodology was based on the ethnographic perspective and we incorporated some contributions of the methodological resource of the auto-biographical account. That is, we conduct in-depth interviews, participant observations, informal talks with multiple educational agents, as well as autobiographical accounts with numerous qom teachers in the region. [ABSTRACT FROM AUTHOR]

Since 1998, I have undertaken fieldwork with the Indigenous peoples of the Argentine Chaco, focusing initially on their dances and embodied practices. After this ethnographic research, I began to think more deeply about the relationships between fieldwork and reflexivity and the possibilities of redefining analytical categories in the global South. The purpose of this article is to revisit my emphasis on a 'dialectical approach to embodiment' as a starting point for analysing cultural transformation in Latin America. I argue that this methodological approach has been closely linked to the interweaving of conflicting embodied experiences and peripheral geopolitical locations. In this regard I analyse how the contradictory experiences identified in my fieldwork with the Toba people, and also in my intersubjective and geopolitical positions as a Latin American academic woman, led me to a critical re-examination of dialectics. Further, I describe how this methodological approach, while well received among Latin American scholars has to some degree been resisted by (North) American and British scholars, and I explore the geopolitical implications of these disparate academic positions. Through these critical movements, I hope to contribute to rethinking dialectics in postcolonial contexts, adding some embodied voices from the Latin American South. [ABSTRACT FROM AUTHOR]

Highlights • There is remarkable subnational variation in the implementation of forest legislation in the Argentine Chaco. • Pressures from large producers and conservationist coalitions shape governors' design and enforcement choices. • When conservationist coalitions are strong, governors design more stringent regulations regardless of producers' power. • When large producers are powerful, governors design flawed regulations and/or do not enforce regulations. Abstract In a context of booming commodity prices, what factors drive subnational authorities to implement forest protection regulations in active agricultural frontiers?. Focusing on one of the world's deforestation hotspots, the Argentine Chaco Forest, we argue that subnational variation in the implementation of forest protection legislation is driven by governors' attempts to avoid conflict produced by agricultural expansion. Through process tracing, we show how governors' implementation decisions—regarding both the design and enforcement of provincial regulations—sought to mitigate pressures from large producers opposed to clearing restrictions and from various groups contesting agricultural expansion. As the power of these actors varies across provinces, governors' conflict avoidance strategies resulted in markedly different subnational regulations as well as contrasting levels of enforcement and deforestation. We substantiate our argument through an empirical strategy that combines department-level geocoded data on deforestation and levels of forest protection in the Argentine Chaco with extensive fieldwork and interviews in the core provinces in which the forest is located. Our findings aim to contribute to academic debates in political science and environmental science on the determinants of subnational policy and deforestation, respectively, and have the potential to inform both donors and policymakers about the factors shaping the uneven impact of decentralized arrangements to combat climate change. [ABSTRACT FROM AUTHOR]

Abstract Trypanosoma cruzi , the etiological agent of Chagas disease, was initially classified into 6 Discrete Typing Units (DTUs). The hybrid DTUs TcV and TcVI are the most frequent in domestic transmission cycles throughout the Southern Cone countries of South America. Here, we genotyped parasite isolates from human residents in Pampa del Indio municipality, Chaco, to further characterize the structure of T. cruzi populations, and to assess the degree of overlapping between the domestic and sylvatic transmission cycles. Artificial xenodiagnostic tests were performed to blood samples from 125 T. cruzi -seropositive people (age range, 3–70 years) who represented 14.3% of all seropositive residents identified. Parasites were obtained from feces of T. cruzi -infected Triatoma infestans examined 30 or 60 days after blood-feeding, and grown in vitro. The cultured parasites were genotyped by means of two PCR-based protocols. DTUs were determined from 39 (31%) patients residing in 28 dwellings. The only DTUs identified were TcV (92%) and TcVI (8–36%). Households with more than one parasite isolate consistently displayed the same DTU. Further sequencing of a fragment of the TcMK gene from selected samples argue against the occurrence of mixed TcV-TcVI infections in the study population. Sequencing data revealed an unexpected degree of genetic variability within TcV including two apparently robust subgroups of isolates. Our results for human residents confirm the predominance of hybrid lineages (TcV and to a much lesser extent TcVI) and the absence of sylvatic genotypes (TcI and TcIII) in (peri)domestic transmission cycles in the Argentinean Chaco area. 245 words. [ABSTRACT FROM AUTHOR]

One of the most proposed climate change mitigation strategies is carbon sequestration by vegetation. This depends on the rate of carbon uptake and transformation in biomass, the rate of release through respiration, and the stability of the stocks to disturbances. Forest diversity influences these factors, in a degree that varies according to certain functional characteristics. The Dry Chaco is the largest dry forest in the world, and one of the regions with the highest deforestation rates of the planet. Our aim was to geographically describe three carbon stock attributes from forest communities of the Dry Chaco Forests in Argentina at the landscape scale: wood density, tree height and annual carbon increase in aboveground biomass, as proxies of forest stability and carbon long-term persistence. In addition, we evaluated the relationships between these attributes and climate features, in the search of potential climate controls. Higher precipitation during the growing season and low mean annual temperature benefited the combination of these three treats related to C storage persistence. The distribution of the most favorable states of the three attributes is centered at the northwestern area of the Dry Chaco. Our geographic description of carbon stocks attributes can contribute to more suitable conservation planning and allows forecasting potential shifts in forests due to climate change. [ABSTRACT FROM AUTHOR]

The area devoted to Silvopastoral systems is increasing worldwide due to its complementary production of beef and wood. Understanding the competition between trees and grasses is critical to identify potential trade-offs in plant production. This article had three objectives: (1) to estimate the seasonal variation of gatton panic (Megathyrsus maximus) productivity and quality in two sites with different annual rainfall, (2) to analyse the effects of tree shadow (“guayacán”, Caesalpinia paraguariensis) on gatton panic above ground primary production (ANPP), and 3) to determine the relative importance of changes in radiation use efficiency (RUE) and incoming radiation (PARi), in defining grass ANPP under trees or exposed to full sunlight. Tree presence reduced gatton panic ANPP by nearly 50%, mainly throughout a reduction in APAR. APAR decrease was not compensated by the RUE increase observed in the wet site and it was exacerbated by a decrease in RUE in the dry site. The decrease in APAR under trees was better explained rather by a decrease in PARi than by the fraction of intercepted PAR. A small increase in shoot grass digestibility was observed under the tree canopy. [ABSTRACT FROM AUTHOR]

Abstract: Fire is a key ecological factor affecting plant dynamics. In the last few decades, fire occurrence in the Chaco region has increased noticeably, challenging the adaptive capacity of plants to regenerate after a fire. Broad‐leaved forb species have been much less studied than woody and graminoids, although they are an important component of fire dynamics. Here we analysed the germination response to heat shock of 70 and 110°C, smoke and their combination in 10 broad‐leaved herbaceous species frequently occurring in the Chaco Serrano of Córdoba province, central Argentina, including five annual (Bidens subalternans, Conyza bonariensis, Schkuhria pinnata, Tagetes minuta and Zinnia peruviana) and five perennial species (Borreria eryngioides, Sida rhombifolia, Solidago chilensis, Taraxacum officinale and Verbena litoralis). We also compared the response of annual versus perennial species. Six species had highest germination when treated with heat and smoke combined, whereas two had lowest germination under this treatment, indicating synergistic and antagonistic interaction of these factors respectively. Most of the species tolerated heat shock (i.e. germination was similar to that in control treatment), whereas others had higher germination in response to heat shock, especially under the moderate 70°C treatment. Germination was higher than control (i.e. no heat and no smoke) after smoke treatment in four species. Perennial species showed higher average germination than annuals in both heat treatments and in the control. Annual species had higher average germination for all treatments involving smoke. The high variability observed at the species level, and the limited number of species studied calls for precaution in interpreting and extrapolating results. Nevertheless, our study shows a general positive response of both perennial and annual species to fire cues, suggesting an advantage of these species for colonizing post‐fire environments, and being favoured under scenarios of increasingly frequent low‐to‐medium intensity fires. [ABSTRACT FROM AUTHOR]

Agricultural expansion and intensification in South America's dry forests and grasslands increase agricultural production, but also result in major environmental trade-offs. The Pampas and Chaco regions of Argentina have been global hotspots of agricultural land-use change since the 2000s, yet our understanding of what drives the spatial patterns of these land-use changes remains partial. We parameterized a net returns model of agricultural land-use change to estimate the probability of agricultural expansion (conversions of woodlands to either cropland or grazing land) and agricultural intensification (conversion of grazing land to cropland) at the 1-km scale for the years 2000 and 2010. Uniquely, our model allowed us to quantify the importance of underlying causes (i.e., changes in agricultural profit) and spatial determinants (i.e., soil fertility, distance to markets, etc.), for Argentina's prime agricultural regions as a whole. We found that cropland and grazing land expansion into woodlands was much less sensitive to changes in profit-related factors than agricultural intensification. Profit-related variables, were a particularly strong cause of intensification in the Pampas, where cropland profits rose by 29% (compared to 18% in the Chaco). This suggests that further conversions of grazing land to cropland in the Pampas and Chaco is likely as long as agricultural demand, and thus returns to agriculture, continue to be high. The moderate impact of profit-related factors on affecting woodland conversion rates also suggests a limited potential of economic policies that affect marginal profits (e.g., taxes or subsidies) to alter deforestation rates and patterns in major ways. Policies that target socio-economic variables not included in our profit-focused framework (e.g., capital availability), area-based interventions (e.g., land zoning), or less-profit oriented actors (e.g., via community-based management) might be more effective in addressing deforestation rates in the Chaco. [ABSTRACT FROM AUTHOR]

Soil evaporation is a dominant water flux of flat dry ecosystems, reducing available water for plant transpiration. Vegetation plays a key role at controlling evaporation, especially by altering soil surface micro-meteorological conditions. Here, we explored the vegetation cover effect on soil evaporation, differentiating the effects of canopy cover (shadow) and of surface cover (litter) in forests and pastures of Dry Chaco rangelands (San Luis, Argentina). We measured daily soil evaporation using irrigated micro-lysimeters installed at regularly spaced (2 m) patches along transects in native dry forests ( n = 54 patches) and pastures ( n = 27 patches). In each forest patch, we established a pair of micro-lysimeters, one with litter (3 cm depth, representing high litter cover conditions of the site) and one with bare soil, but in pastures, only one micro-lysimeter with bare soil was installed at each patch (representing the typical no litter cover conditions of pastures of the study site). We found that, when soil water was not limiting, litter cover had the strongest effect in reducing evaporation rates, with a 4- and 6.4-fold reduction respect to bare soil micro-lysimeters in the forest and pasture, respectively. Evaporation decreased sharply with declining incident radiation fraction in bare soil micro-lysimeters from 5.6 mm/day (full radiation) to 3.5 mm/day (full canopy shadow; R2 = 0.50). Litter-covered micro-lysimeters showed lower and more stable evaporation rates, decreasing only from 1.35 to 1.03 mm/day under the same radiation conditions ( R2 = 0.10). In accordance with J.T. Ritchie evaporation model, we identified a threshold of ~10.5 mm of cumulative evaporation at which evaporation switched from energy to water limitation in all situations, as revealed by declining evaporation rates and raising surface temperatures. Under typical wet-summer conditions, the pasture, the forest with bare soil, and the forest with litter would need on average a drying cycle of 1.5, 2.5, and 9.5 days, respectively, to reach that threshold. Simulations showed that, considering the distribution of rainfall events at our study site, litter would maintain evaporation in the energy-limited mode most of the time (68.8% of summer days), potentially favouring transpiration. The ecohydrological key role of soil litter controlling evaporation highlights the importance of an accurate assessment of management practices controlling the evaporation/transpiration partition in dry ecosystems. [ABSTRACT FROM AUTHOR]

Background: Rural populations in the Gran Chaco region have large prevalence rates of Trypanosoma cruzi infection and very limited access to diagnosis and treatment. We implemented an innovative strategy to bridge these gaps in 13 rural villages of Pampa del Indio held under sustained vector surveillance and control. Methodology: The non-randomized treatment program included participatory workshops, capacity strengthening of local health personnel, serodiagnosis, qualitative and quantitative PCRs, a 60-day treatment course with benznidazole and follow-up. Parents and healthcare agents were instructed on drug administration and early detection and notification of adverse drug-related reactions (ADR). Healthcare agents monitored medication adherence and ADRs at village level. Principal findings: The seroprevalence of T. cruzi infection was 24.1% among 395 residents up to 18 years of age examined. Serodiagnostic (70%) and treatment coverage (82%) largely exceeded local historical levels. Sixty-six (85%) of 78 eligible patients completed treatment with 97% medication adherence. ADRs occurred in 32% of patients, but most were mild and manageable. Four patients showing severe or moderate ADRs required treatment withdrawal. T. cruzi DNA was detected by qPCR in 47 (76%) patients before treatment, and persistently occurred in only one patient over 20–180 days posttreatment. Conclusions and significance: Our results demonstrate that diagnosis and treatment of T. cruzi infection in remote, impoverished rural areas can be effectively addressed through strengthened primary healthcare attention and broad social participation with adequate external support. This strategy secured high treatment coverage and adherence; effectively managed ADRs, and provided early evidence of positive therapeutic responses. [ABSTRACT FROM AUTHOR]

This paper analyses the possibilities for participation and bilingual learning of Wichi children in Chaco (Argentina) in the contexts in which they are currently educated. From a theoretical and methodological approach that links language learning and participation in social and historically located events, two learning environments are discussed: (i) with two teachers (a teacher fluent only in Spanish and a bilingual assistant); and (ii) a bilingual teacher. The data analysis reveals that in type (i) environments the common participation formats, as well as the method in which the semiotic resources at stake are managed, limit the possibilities of bilingual learning in Wichi pupils. However, the more open and flexible interaction formats in type (ii) environments, as well as the activation of bilingual speaking modes, promote spontaneous and guided participation by pupils, therefore offering a greater potential for bilingual learning. Both cases reflect the place that languages and speakers hold in classrooms. [ABSTRACT FROM AUTHOR]

The article examines the deployment of social networks of pastoral aborigen in the Argentinean Chaco region between 1970 and 1985. It describes the structuring process of these networks and analyzes the relations that pastoral aborigen agents held with anthropologists and anthropological knowledge. The analysis is based on files -which the author has had access to- located in what functioned as a regional training center. The paper suggests that, being Development an hegemonic paradigm in the 1960s, it created conditions of possibility for the deployment of these networks. Furthermore, the article argues that ethnic markings on populations in which the pastoral agents were involved with were mediated by an incorporation of different anthropological knowledge. In this regard, people first assumed as "the poorest of the poor" gradually became named as "communities" and pueblos aborígenes. [ABSTRACT FROM AUTHOR]

Clearance for agriculture or cattle ranching was the dominant land-cover change during the last two decades in the South American Dry Chaco. The Argentinean portion has been particularly affected, presenting greater deforestation rates than the continental and global averages. Little is known on the control factors of the location and the spatial clearance patterns. In this article we studied (a) deforestation dynamics in the Argentinean Dry Chaco and the factors determining land clearing locations for the last 25 years; (b) changes in the relative impact of those factors through time and space; and (c) the effect of regulations aimed to control the location and magnitude of land transformation. We also tested the “expansion of the agricultural frontier” hypothesis for the Argentinean Chaco. To identify the factors that defined agricultural expansion we used binomial logistic models that were fitted to a set of independent variables (bio-physical, infrastructure and political factors) that could eventually influence the distribution of new agricultural areas. Results indicate that the Forest Law devised by the Argentinean federal government to control the clearing process was insufficient to restrict both the area transformed per year and clearance locations. Agriculture is expanding over marginal areas and land clearing dynamics have been increasingly associated to the proximity to already cleared areas, defining a frontier—advancement pattern which gives the idea of a contagion process. According to our results, the relative importance of the anthropic factors associated to the agricultural expansion in the region increased through time. [ABSTRACT FROM AUTHOR]

Edible plant species and their parts used by indigenous tapiete people in northeastern Salta province, Argentina are identified, as well as their gathering, elaboration, consumption and storage practices. The ultimate aim of this work is to contribute to the recording and appreciation of tapiete people knowledge about this matter. Five fieldworks were made to the semiarid northern Chaco and to Tartagal city, where ethnobotanical data were obtained from 75 interviews with a total of 32 qualified and occasional tapiete collaborators. Each of the edible plants was collected and identified by the authors and deposited at the Ruiz Leal Herbarium (MERL). A total of 54 native plants, belonging to 23 botanical families used as food by the tapiete, are recorded as forming part of 106 preparations, or consumption forms, and 13 forms of conservation. The main edible species are Anisocapparis speciosa, Prosopis aff. elata and Prosopis alba with six applications each, and Ziziphus mistol, Geoffroea decorticans and Funastrum clausum with four applications each. Most of these applications (55%; 59) do not include any preparation --they are consumed raw-, the 21% (22) are eaten cooked (boiled or roasted), while their use in beverages, condiment and flours represent a minority of their applications (24%; 25). Consumption of the leaves of Passiflora mooreana and P. cincinatta is registered here for the first time by ethnic groups from the Gran Chaco. [ABSTRACT FROM AUTHOR]

The puma Puma concolor is the most widely distributed felid in the Americas. Although it utilizes human-modified landscapes, its extensive territorial requirements, trophic needs, and real or perceived threats to livestock render the puma susceptible to conflict with humans. Our objectives were to evaluate the population density, habitat use, and puma-human conflict in the Argentine Chaco. We conducted camera-trap surveys and interviews over a three-year period, at three sites with different levels of legal protection and with different ranch outpost and livestock densities: Copo National Park (1204 trap days, 24 stations, 17 interviews, national park, lowest ranch/livestock density), Aborigen Reserve (1993 trap days, 29 stations, 13 interviews, indigenous reserve, medium ranch/livestock density) and El Cantor (2129 trap days, 35 stations, 11 interviews, no protection, highest ranch/livestock density). Puma population density was low (<1 individual/100 km 2 ) and we found no significant differences in puma density across the three sites. Occupancy models show a positive relationship between puma detectability and the distances from vehicle roads. Legal protection status of the área does not positively affect puma density, probably due to the large edge effect, and weak law enforcement capacity at Copo National Park. Low density of pumas at the three sites could result primarily from retaliation killing of pumas by local ranchers in response to predation on goats. Pumas in the Chaco require effectively managed protected areas, regulation of wildlife hunting and livestock management practices to minimize depredation. [ABSTRACT FROM AUTHOR]

The performance of a mixed starter culture, SAS-1, comprised of the autochthonous strains Lactobacillus sakei ACU-2 and Staphylococcus vitulinus ACU-10, was evaluated into the production process of a traditional dry sausage. Microbiological, physicochemical and sensory analyses were carried out to accomplish this goal. Results showed an improvement in performance through the introduction of SAS-1; adding mixed starter culture rapidly decreased pH, inhibited the growth of contaminant microorganisms and enhanced the beneficial ones, diminished TBARS, and highlighted color and aroma attributes. However, most influential organoleptic descriptors among consumer acceptance were not affected by the addition of the starter. This starter culture would represent a valuable tool to improve the homogeneity of artisanal manufacture of this traditional food. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the composition of the Culicidae community in three environments with different degrees of anthropic disturbance in the province of Chaco. The nonparametric richness estimator ACE was calculated to measure the completeness of the sampling in each environment, and the diversity of each environment (α-diversity) were estimated. The composition, abundance and uniformity of species from the different environments were compared by means of range-species curves. β-diversity was measured as species complementarity, which allowed us to know the degree of dissimilarity among the environments. The synanthropic index was estimated, identifying urban environment (synanthropic) species, eusynanthropic species, and wild species. The influence of climatic factors (mean temperature, relative humidity and rainfall) on the monthly and annual variations of the identified mosquito species was analysed using multilevel Poisson models with over-dispersion. The wild environment showed higher diversity and the semi-urban environment higher species richness. Despite having lower S and abundance, the urban environment showed greater diversity than semi-urban environment, although it also showed lower completeness, which means S could increase. Anthropogenic disturbance can lead to the elimination and/or modification or substitution of habitats, with the subsequent loss of richness in the more sensitive species of Culicidae fauna, although the conditions are also favourable for the settling of opportunistic and exotic species well-adjusted to disturbed environments. Most of the species abundances were positively influenced by the analysed climatic variables. The study area showed a rich Culicidae fauna of public health significance, with a risk of pathogen transmission, suggesting the need of further studies and the febrile and entomological surveillance. [ABSTRACT FROM AUTHOR]

Soil quality (SQ) is a multidimensional concept based on the use of indicators. Indicators integrated assessment gives much more information than individual data and a select set of parameters; solve operational and economic aspects of measurement and monitoring. One of the most important effects of Land Use Change (LUC) is the alteration of original properties of native forest soil. Chaco province has no previous published studies on soil quality (SQ) for cleared lands. In Argentina between 1956 and 2000s the most significant changes occurred in West Subhumid Chaco, where crops expansion and deforestation were the highest of the country. The objectives of this study were: (1) to select SQI in native forest soils cleared for agricultural use in an area of Chaco province under LUC without available information; (2) to obtain values from these indicators for this environment, in order to increase current knowledge about LUC effects. Results show that LUC caused a significant degradation in these parameters compared with soil of pristine condition, affecting physical and chemical quality in a relatively short time. TOC was the most sensitive indicator and decreased between 40 and 11% in cleared sites at surface. The selection by mixed models in a first step and then by multivariate techniques was effective because some variables were more consistent to discriminate in the complete dataset the unaltered condition (NF) of the disturbed (CL), taking into account the inherent variability of sampling sites and depths. Selected indicators were: total organic carbon (TOC), particulate organic carbon (POC), total nitrogen (N), bulk density (Bd), and EF (erodible fraction); high correlation between some of them would allow performing an even tight selection. These indicators varied in performance between studied depths. This SQI set is feasible to recommend as a tool for soil health diagnostic and monitoring, prior to granting management plans currently submitted within the legal framework of native forests. [ABSTRACT FROM AUTHOR]

We explored age-related parameters and growth patterns in a population of Dermatonotus muelleri inhabiting the Arid Chaco, at the southern limit of the species' distribution range using skeletochronology. In addition, we studied sexual size dimorphism and female reproductive investment. Males and females attained sexual maturity at a similar age (2 years) and both had a low reproductive lifespan (3 years). Females were significantly larger than males and had a higher reproductive investment compared to other anurans. The growth rate coefficient (k) was similar in males (1.14) and females (1.07), indicating that the sexual size dimorphism in this species is caused by differentiated growth before sexual maturity. Overall, we suggest that the short reproductive lifespan justifies the high reproductive investment in the studied population. [ABSTRACT FROM AUTHOR]

The Chaco region is a sedimentary basin limited by the Andes and the Brazilian craton. This South American subtropical plain is defined as large alluvial fan sediments of the main rivers that were repeatedly deposited during the late Quaternary under diverse climatic conditions. The Eastern Chaco is characterized by semideciduous forests intermingled with extensive palm-savannas, with gallery forests being the common vegetation along the banks of the main rivers and their western tributaries. These vegetation patterns of the Chaco have been proposed to be the result of the Pleistocene–Holocene alluvial dynamics of the plain as well as of the intensive migration of fluvial belts of the main rivers. Although no data are available on the paleoflora of the Chaco plain, plant fossil impressions are found in the banks of the low Bermejo River, which flows along the Eastern Chaco phytogeographic region. Here, we analyze paleoagrostological impressions recovered from two fossiliferous localities in order to provide insights into the environmental history of the Chaco region. Sixty complete Poaceae spikelet impressions were studied morphologically and compared with extant Chaco grass species. For each fossil spikelet, 11 morphological characters were described and statistically analyzed. All spikelets were found to belong to the Panicoideae subfamily, and some have consistent morphological features with this subfamily; hence, we assign them to the extant genera Cenchru s, Echinochloa , Hymenachne , and Paspalum . These impressions are the first floral remains found in the Eastern Chaco and collectively suggest that environmental and climatic conditions from these sediments corresponded to a subtropical humid climate and that vegetation was similar to the extant Eastern Chaco flora. [ABSTRACT FROM AUTHOR]

Considering uncertainties regarding climate variability, the objective of this study was to make a long-term (1901–2011) comparative assessment of the impact of land-use decision (changes in the cultivated area) and technology adoption as adaptative mechanisms of the rural sector in the Argentine Chaco and the US Southern Plains. Different sources of data on climate (precipitation, minimum, mean and maximum temperature and evapotranspiration), land-use change (proportion of cultivated area) and technology adoption were used. This work involved three main analytical steps: i) Principal Components Analysis (PCA) was applied to identified the dominant components of data variance, ii) the relationship between the residuals of precipitation and land-use change was assessed by means of a simple regression analysis and iii) technology adoption was evaluated through a proxy based on historical changes in the yield of maize ( Zea mays L.). The results showed that farmers in both countries relied on two common adaptative strategies to face climate perturbations during the study period: i) land-use change (a simple binary decision of planting or not planting in response to climate conditions) during a first stage, and ii) the introduction of adaptative technologies to smooth the impact of climate during the second one. That substitution of adaptative strategies begun during the 1940 decade in the US Southern Plains, and around 30 years later in the Argentine Chaco. The adoption of technologies and agronomic practices explained the sensitivity decay of the cultivated area to the climatic variability during the second stage. The incorporation of improved hybrids with higher drought resistance plus the adoption of tilling practices like minimum tillage or no-till, the input of fertilizers, pesticides and irrigation water (the last one in US, only) became a successful strategy to mitigate the risk of climate perturbation. [ABSTRACT FROM AUTHOR]

The expression Forest Transition (FT) and Ecological Transition (ET) were coined to describe the recovery path of forested areas (or more general natural vegetation) after heavy conversion into croplands. FT/ET would be driven by two main socio-economic controls: a) agricultural intensification in the most productive areas and the simultaneous reduction of cropped area in the less suitable areas ( land-sparing ); and b) rural population migration from rural to urban areas. In the argentine portion of the Semiarid Chaco a rapid and extensive clearing for industrial agriculture and cattle ranching based on sown pastures is taking place. In this article we evaluated the occurrence, magnitude and localization of FT/ET in the argentine portion of the Semiarid Chaco during the 1977–2007 period using an approach based on remotely sensed data. From land cover maps we derived three diagnosis variables of FT/ET: (1) the area of natural vegetation at the end of the study period; (2) the rate of annual clearance (natural vegetation loss) for the whole period; and (3) the temporal change of the area of natural vegetation in the last portion of the study period. The diagnosis variables were combined to derive 12 classes (landscape types). We observed a systematic loss of the surface occupied by natural vegetation. Industrial agriculture grew in aggregated patches generating a homogenization of the landscape. In only a 4.8% of the study area we observed a pattern of change compatible with a FT/ET. In contrast, in a 34% of the study region (9.57 million ha) a clear negative trend in the cover of natural vegetation was observed during 1977–2007 period. The area that had a negative trend in the cover of natural vegetation was 7 times greater than the portion of the region experiencing positive trends. Such number indicates an imbalance in the landscape dynamics that would further reduce areas covered by natural vegetation. [ABSTRACT FROM AUTHOR]

The aim of this work was to characterize the spatial and temporal dynamics of the transformation of the natural cover in the Dry Chaco ecoregion from 1976 to 2012. Dry forests in this region have one of the highest deforestation rates in the world. We analyzed 44 Landsat scenes, including part of Argentina, Paraguay and Bolivia. The analysis was based on tracking individual transformed plots of the entire Dry Chaco region for over more than three decades using the same protocol. Until the end of 2012 15.8 million ha of the original habitats of the Chaco were transformed into croplands or pastures. Our study showed that the greater annual rates of transformation were observed in Paraguay, where deforestation increased dramatically in the last decade, reaching values higher than 4.0% in 2010, the highest historical value in the entire region. The size of the transformed plots increased significantly through the studied period both in Argentina and Paraguay, while in Bolivia decreased. At the landscape level, the use of several fragmentation indices showed the disruption of the continuity and connectivity of the original vegetation. The spatially explicit description of the dynamics of transformed areas is an indispensable tool for natural resources management, territorial planning and deforestation impacts assessment. The developed geo-database is available online at http://monitoreodesmonte.com.ar/ for further analyses and use. [ABSTRACT FROM AUTHOR]

Rainwater harvesting (RWH) has been essential for the establishment of human settlements in many dry regions of the world that lacked suitable surface or groundwater resources. A vast fraction of the South American Dry Chaco ecoregion still relies on RWH to support, not only livestock production, but domestic and industrial uses as well. As a result, water capture and storage infrastructure is widely disseminated throughout the region. In this paper we characterized the most typical RWH systems in two contrastingly developed sub-regions of Dry Chaco, ranging from extensive ranching to intensive beef and dairy production (central Argentina and western Paraguay, respectively). In each sub-region, we quantified RWH systems density, spatial distribution and associations with landscape features; furthermore, we illustrated how the daily dynamic of water stock in a typical RWH system contributes to assess their capture and storage efficiency. We found that randomly distributed low sophisticated RWH systems prevailed in central Argentina, while clustered distributed high sophisticated ones were more common in western Paraguay. RWH systems density was ten times higher in western Paraguay (0.94 vs. 0.098 units/km 2 ), showing an exponential association with land cleared fraction and proximity to villages. The daily dynamic of water stock of the RWH impoundment showed that water harvest events were exponentially associated with precipitation magnitude events (R 2 = 0.86), while annual water losses were explained by infiltration and evaporation fluxes (59 vs. 41%, respectively). Across both sub-regions, RWH accounts for less than 1% of the annual precipitation, playing a minor role on the regional water balance; however at a local level, they can affect several hydrological fluxes including the onset of groundwater recharge and the mitigation of extreme runoff events. [ABSTRACT FROM AUTHOR]

Environmental factors and land use control habitat quality and resources availability, thus regulating species distribution. Land tenure in general, and particularly traditional indigenous properties, strongly influence land use in forest ecosystems, but their association with biodiversity is poorly explored. We surveyed 43 forests in the Northern Argentina Gran Chaco, to (1) compare species diversity and composition of birds, mammals and trees between land tenures across a 17 million-hectares region; and to (2) compare diversity between Wichí indigenous properties and non-indigenous properties, within a more restricted geographic range to control for climatic and soil factors ( n = 19). Contrary to our expectations, protected areas did not include higher biodiversity, although they showed higher densities of species specifically targeted for human harvest. Wichí properties were the most original regime in terms of community composition of birds and trees. Every land tenure had particular indicator bird and tree species; thus a territorial conservation strategy could include a combination of all them, with a special focus on indigenous properties. Land tenure differences in biodiversity could be the complex result of different habitat quality derived from land use practices and of different geographic location. [ABSTRACT FROM AUTHOR]

In most tropical and subtropical biomes, conservation strategies are mainly focused on the preservation of forests. However, neotropical dry forest and savanna ecoregions include open habitats that may deserve conservation attention. We analyzed the historical patterns and potential distribution of natural grasslands, as well as their biodiversity in the northern Argentina dry Chaco, which is one of the largest and yet most rapidly transforming neotropical ecoregions. Paleocological literature, historical records, and bioclimatic modeling support the hypothesis that Chaco grasslands distribution was more extended in the past, and has been historically reduced by woody encroachment resulting from environmental changes occurred in the past century. Recent research shows that natural grasslands host distinctive components of the Chaco biodiversity, and a significant proportion of the vertebrate species have a negative association with woody biomass. Ongoing land use trends continue to threaten native grasslands both in unprotected sectors (where they are converted into agriculture and planted pastures) and inside protected areas (were fire suppression is favoring woody encroachment). Current conservation policies (Protected Areas, Argentine forest law, REDD+) neglect the importance of native grasslands for biodiversity conservation. Such forest-centered initiatives should be revised to specifically include native grasslands and their biodiversity into land use strategies that adequately balance agriculture and livestock production with biodiversity conservation. [ABSTRACT FROM AUTHOR]

Like in other semiarid areas of the world, farming systems in semiarid Chaco tend to use water-conservative crop systems to minimize production risks associated to water stress. While this strategy aims to stabilize crop yields and farmers income, the underutilization of water resources in wet years may result in heavy deep drainage water losses which could potentially lead to the development of dryland salinity. Conversely, more intensive crop systems that consume water exhaustively present lower drainage rates but are more prone to crop failure. We employed a monthly soil water balance approach to analyze the productive and ecohydrologic effects of five different farming systems across the region (winter, spring, summer, late-summer and a winter–summer double crop system) and to assess the possibility of minimizing emerging trade-offs between them through flexible water-informed cropping sequences. Our results indicate that water stress diminishes as crop systems are delayed towards the rainy season (winter > spring > summer > late-summer), but the productively safer late-summer strategy is the one with highest drainage rates. In most of the region, the relatively high production risk and insignificant drainage probability generally determine the convenience of conservative late-summer systems. However, in areas (or years) with higher amount and/or seasonality of rainfall, more intensive double-crop systems are necessary to minimize the likely high drainage fluxes. As rainfall is highly variable from one year to the other, the knowledge of soil water content at the onset of the season is useful to predict part of the available water offer and to asses expected production and ecohydrologic risks. In the most drainage-prone areas the implementation of flexible sequences that alternate conservative and intensive crop systems depending on soil water status, significantly reduced mean annual drainage with an acceptable increase in mean water stress index. [ABSTRACT FROM AUTHOR]

Deforestation in the Northern Argentine Dry Chaco (NADC) has been mainly driven by soybean expansion and, more recently, by the expansion of implanted pastures. In areas with fast land use transformations, it is important to identify variables that determine the spatial distribution of land use change. The kinds of exploratory analyses that do so contribute to understanding the logic of deforestation agents and to identifying more probable sectors for land use change. We produced maps of cultivated land in NADC for different years (1972, 1991, 1997, 2002, 2007). Based on these maps, we evaluated the importance of environmental and accessibility variables over the spatial distribution of cultivated land in NADC using multiple and simple logistic regressions. Environmental variables (soil suitability for agriculture, rainfall, topography) and accessibility variables (distance to main roads, distance to main towns) were used to fit logistic regressions to the occurrence of cultivated land at different years as dependent variable. Goodness-of-fit was evaluated by the Relative Operating Characteristic (ROC) and Pseudo R2 indices. Results indicate that the main variables explaining the spatial distribution of cultivated land in 2007 are distance to main towns (ROC = 0.76; Pseudo R2 0.12) and soil suitability (ROC = 0.72; Pseudo R2 0.11). The capacity of environmental and accessibility variables to explain the spatial distribution of cultivated land decreased through time (ROC in 1972 = 0.91 and ROC in 2007 = 0.77). Results also suggest that rainfall has not been a major restriction to cropland expansion, and that the main limitations are imposed by infrastructure and services provided from main towns. A decreasing goodness-of-fit over time suggests that initial limitations have been overcome by cropland expansion and the consolidation of productive areas. Based on these results, we suggest that cropland expansion may generate positive feedbacks in infrastructure and services (i.e. agglomeration economies) that could explain why initial limiting factors related with distance to roads and towns have been gradually overcome. [ABSTRACT FROM AUTHOR]