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Question: Do shrubs negatively affect the germination of perennial grass species in regeneration microsites? We experimentally analyzed the effect of soils from plant patches dominated by two shrub species (Larrea divaricata and Schinus johnstonii) and their propagules on the germination of three co‐dominant herbivore‐preferred perennial grass species (Poa ligularis, Nassella tenuis and Pappostipa speciosa). Location: Patagonian Monte, Chubut Province, Argentina (42°07′ S, 64°59′ W; 43°06′ S, 65°43′ W; 42°29′ S, 66°34′ W). Methods: We conducted two simultaneous microcosm experiments. In the first experiment, we sowed perennial grass propagules of the three species alone and combined with non‐scarified shrub propagules in Petri dishes with three substrate types (filter paper, inert soil and soil from shrub patches). In the second experiment, we sowed perennial grass propagules of each species combined with scarified and non‐scarified propagules of both shrub species in Petri dishes with soil taken from plant patches dominated by L. divaricata and by S. johnstonii. Both experiments lasted 3 months. We calculated the germination proportion and mean germination time (MGT) of propagules for each perennial grass species in each treatment. Results: Propagules from neighboring shrubs had a clearer negative effect on grass germination compared with shrub soils. Shrub propagules negatively affected the germination proportion of P. ligularis and N. tenuis, and induced longer MGT in the three perennial grass species. The combination of S. johnstonii soil and propagules negatively affected P. ligularis and P. speciosa germination. The combination of L. divaricata soil and scarified propagules completely inhibited P. speciosa germination. Conclusions: Our results highlighted the complexity of interactions between shrubs with high phenolic contents (soils and propagules) and the germination of perennial grass species in arid environments. Schinus johnstonii soil and propagules had stronger effects on perennial grass germination than L. divaricata soil and propagules. The negative effects of shrubs on microsite quality and germination processes depended on the specific shrub/grass interaction. [ABSTRACT FROM AUTHOR]

Describes the difficulties Argentina's medical schools are likely to face in implementing a problem-based learning (PBL) curriculum. Outlines the basic requirements for successful implementation of PBL curricula and describes the contradiction in Argentina between a health care system that forces specialization and the efforts of medical schools to produce generalists. (SLD)

Pension policy is a highly political issue across Latin America. Since the mid-2000s, several countries have re-reformed their pension systems with a general trend toward more state involvement, yet with significant variation. This article contends that policy legacies and the institutional political setting are key to understanding such variation. Analyzing the cases of Argentina, Bolivia, and Chile, this article shows that where a weak legacy, characterized by low coverage and savings rates, a weakly organized pension industry, and strong societal groups that oppose the private system, combines with a strong institutional setting, characterized by a government with large support in Congress and where the president concentrates decisionmaking, re-reform outcomes may lead to the outright elimination of the private pillar. Conversely, where a strong legacy combines with a weak institutional setting, re-reform outcomes will tend to maintain the private pillar and expand only the role of the public one. [ABSTRACT FROM AUTHOR]

The unusual findings of Lower and Middle Ordovician tiny sclerite-type elements in the San Juan Formation of the Argentine Precordillera are described and analysed. The well-preserved silicified and phosphatized association consists of spindle-shaped morphotypes, ornamented with small regular granules or tubercles with some elements connected by their tips in a linear manner. Some morphologic characteristics of these mostly fused or connected sclerite-type elements are present in the alcyonacean octocorals. Their affinities with sponge spicules are also discussed. The oldest records of alcyonacean sclerites have been dated as late Llandovery to late Wenlock (Silurian). The discovery of possible octocoral skeletal elements in the Lower Ordovician of western Argentina may represent the oldest occurrence of such fundamental skeletal elements in the evolutionary history of the octocorals. Although a proper group assignment is still speculative at this state of knowledge, there is an implication that these early forms could be axial skeletal elements comparable to those seen in the Scleraxonia or Calcaxonia octocorals. One new genus Catenatus and new species Catenatus argentinus are described. [ABSTRACT FROM AUTHOR]

Background: Convalescent plasma, widely utilized in viral infections that induce neutralizing antibodies, has been proposed for COVID-19, and preliminary evidence shows that it might have beneficial effect. Our objective was to determine the risk factors for 28-days mortality in patients who received convalescent plasma for COVID-19 compared to those who did not, who were admitted to hospitals in Buenos Aires Province, Argentina, throughout the pandemic. Methods: This is a multicenter, retrospective cohort study of 2-month duration beginning on June 1, 2020, including unselected, consecutive adult patients with diagnosed COVID-19, admitted to 215 hospitals with pneumonia. Epidemiological and clinical variables were registered in the Provincial Hospital Bed Management System. Convalescent plasma was supplied as part of a centralized, expanded access program. Results: We analyzed 3,529 patients with pneumonia, predominantly male, aged 62±17, with arterial hypertension and diabetes as main comorbidities; 51.4% were admitted to the ward, 27.1% to the Intensive Care Unit (ICU), and 21.7% to the ICU with mechanical ventilation requirement (ICU-MV). 28-day mortality was 34.9%; and was 26.3%, 30.1% and 61.4% for ward, ICU and ICU-MV patients. Convalescent plasma was administered to 868 patients (24.6%); their 28-day mortality was significantly lower (25.5% vs. 38.0%, p<0.001). No major adverse effects occurred. Logistic regression analysis identified age, ICU admission with and without MV requirement, diabetes, and preexistent cardiovascular disease as independent predictors of 28-day mortality, whereas convalescent plasma administration acted as a protective factor. Conclusions: Our study suggests that the administration of convalescent plasma in COVID-19 pneumonia admitted to the hospital might be associated with improved outcomes. [ABSTRACT FROM AUTHOR]

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

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias 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.)

Purpose: The impacts of sheep grazing on soil microorganisms and enzyme activities are not yet fully understood in arid and semi-arid regions, despite the fact that most grazed lands are drylands. Therefore, this study aimed to analyze the temporal (seasonal samplings in a 2-year study) and spatial (plant-covered patches vs. inter-patches) variability of soil dehydrogenase (DHA) as an indicator of soil microbiological activity in two sites under different grazing managements in the arid Patagonian Monte. Materials and methods: We selected two sites with different grazing managements: site G is currently under grazing disturbance and has been grazed by sheep since the beginning of the twentieth century, while site NG used to be grazed by sheep until 2003 (6 years before the first sampling) when sheep were gradually removed. Soil samples were collected at plant-covered patches (P) and inter-patches (IP) within G and NG at 7 sampling dates (distributed seasonally along a 2-year study), and in each sample we determined soil DHA. We further analyzed environmental properties that could have influenced the observed patterns of DHA by measuring soil moisture, soil penetration and gravel content, and plant litter biomass. Results and discussion: In the grazed site, there was a significantly higher soil DHA activity in P than in IP along the whole study timeframe, while no significant differences were observed in soil DHA between P and IP in the non-grazed site. In both sites, soil DHA activity positively correlated with plant litter biomass. In addition, a significant positive correlation between DHA and soil penetration, and a significant negative correlation between DHA and gravel content were detected only in the grazed site. Although significant differences in soil DHA among dates were detected in both G and NG, this variable did not show a seasonal pattern. Conclusions: These results suggest that grazing may increase soil DHA spatial heterogeneity, possibly associated with sheep-induced soil compaction through trampling and increased gravel content through erosion. The lack of significant differences in soil DHA activity between patches and inter-patches in the non-grazed site could be associated with vegetation not showing a clear impact on soil DHA in the time-frame elapsed since sheep-removal. [ABSTRACT FROM AUTHOR]

The concentrations of major and trace elements in Argentinean commercial powdered milk samples were determined with inductively coupled plasma mass spectrometry. Also the daily intake (DI) was calculated for adults and infants. The concentrations of B, Mg, Na, K and Ca were significantly higher in skimmed milk. Cu, Mo, Fe, Mn and Zn were significantly higher in infant formula. All the DIs were below the tolerable upper intake levels. The mean As concentration (26.0 ± 8.6 ng/g) in the powdered skimmed milk samples was slightly higher than in the others. Mean Pb concentrations ranged from 4.1 ± 2.1 to 13.5 ± 8.2 ng/g. The highest mean U concentration was 7.8 ± 2.6 ng/g for whole milk. This study contributes to the knowledge of major and trace elements in powdered milk and its contribution to the diet in Argentina. [ABSTRACT FROM AUTHOR]

Aims Plants play an important role in ecosystem processes. Functional meaning of trait variation in wide environmental gradients is well known but is scarcely known across narrow gradients. We analyze the variation of morphological, physical and chemical traits of dominant plant species and the potential rates of dry mass loss and N release/immobilization during senesced leaf decomposition of these species across a narrow aridity gradient, and to identify indicative traits useful to set species functional groups sharing decomposition patterns. Methods We analyzed the variation of morphological, physical and chemical traits (specific leaf area, seed mass, N and soluble phenols in green and senesced leaves, plant height) in dominant plant species at 12 sites across an aridity gradient in northern Patagonia, Argentina. We collected senesced leaves of each plant species at each site and used them to estimate the potential rates of dry mass loss and N release/immobilization from decomposing senesced leaves in a microcosm experiment. We analyzed the variation of plant traits and decomposition rates across the aridity gradient. We grouped plants species according to growth forms (perennial grasses, deciduous shrubs, evergreen shrubs) and different combinations of morpho-physical and chemical traits of green and senesced leaves and compared the potential rates of dry mass loss and N release/immobilization during leaf decomposition among these groups delimited by each grouping criteria. Important Findings Plant traits did not vary across the aridity gradient. The potential rate of dry mass loss was positively related to aridity, while the potential rate of N release/immobilization did not vary across the gradient. Grouping species by separately morpho-physical and chemical traits resulted in a large overlapping in mean values of decomposition rates among groups. In contrast, plant groupings based on growth forms and those including all morpho-physical and chemical traits of green or senesced leaves yielded groups with differentiated rates of decomposition processes. The two latter groupings clustered species from more than one growth form indicating some overlapping in the rates of decomposition processes among species of different growth forms. Among traits, N concentration in senesced leaves and plant height explained the highest variation in decomposition rates being positively related to potential rates of dry mass loss and N release/immobilization. We concluded that plant groupings based on morpho-physical and chemical traits of either green or senesced leaves may be more powerful to differentiate functional species groups sharing decomposition patterns than the growth form grouping. Moreover, plant height and N concentration in senesced leaves may be considered relevant synthetic functional traits in relation to decomposition processes in narrow aridity gradients. [ABSTRACT FROM AUTHOR]

A laminated, dome-shaped structure (with stromatolitic features) forming reefs in the Ordovician of western Argentina was previously described as a probable primitive form of stromatoporoid named as Zondarella. New collected material allowed to realize that the laminae are constituted by well-preserved filaments, assigned to the cyanobacterium Acuasiphonoria Liu et al., 2016 , which forms the lamination seen in " Zondarella " alternating filament density and orientation. According to this, the stromatoporoid status of the growth form named " Zondarella " is no longer sustainable, and is considered to be a skeletal stromatolite. Stromatolites occur widely in Furongian and Early Ordovician rocks, slightly predating the Ordovician cyanobacterial calcification episode, indicated by a many-fold increase in global calcified cyanobacteria diversity during the late Middle to Upper Ordovician. The Acuasiphonoria stromatolites of the mid- to upper San Juan Formation are earliest Dapingian, occurring together with renalcids and Allonema boundstone. Reefs of the Argentine Precordillera prove the persistence of stromatolite reefs without a conspicuous metazoan framework into the early Middle Ordovician. The lower Dapingian reefs bearing calcified cyanobacterial stromatolites of the San Juan Formation are morphologically and dimensionally comparable to lower Cambrian reefs, sharing similar paleoecological features such as community structure and composition; they also record an increase in calcimicrobial diversity and appeared directly above the Basal Dapingian Negative Isotopic Carbon Excursion. This suggests that a replication of similar environmental or oceanographic states, might have triggered the return of comparable ecosystems. • Calcified cyanobacteria built skeletal-stromatolite reefs in The Middle Ordovician of the Argentine Precordillera • The Middle Ordovician Zondarella , thought to be a stromatoporoid, is actually formed by calcified filamentous cyanobacteria. • Early Middle Ordovician reefs are structurally and ecologically similar to early Cambrian archaeocyathid reefs • The post Cambrian persistence of stromatolite reefs in shallow waters is consistent until the Middle Ordovician [ABSTRACT FROM AUTHOR]

A Mississippian hexactinellid sponge from the western Argentina improves the extremely poor late Paleozoic sponge records from Gondwana. The sponge is included in the subfamily Thysanodictyinae of family Dictyospongiidae. The new genus and species Minitaspongia parvis is erected, and its well-preserved spicular structure is described in detail representing the first approximation of the spicule assemblage in Thysanodictyinae. The skeleton is clathrate, three-dimensional with at least two ranks of rectangular openings. This first report of this subfamily outside North America represents the best-known hexactinellid and the first dictyosponge record from the Carboniferous of Gondwana. Unlike the occurrences of Thysanodictyinae in North America, with thick skeletons linked to high-energy shallow water settings, Minitaspongia occurs in low-energy water siliciclastic settings related to a cold climate and glacimarine deposits. Accordingly, the complex wall structure of this sponge should not be invoked as a necessary adaptation to high energy and shallow water settings. [ABSTRACT FROM AUTHOR]

The article discusses the 21st International Congress of Nutrition (IUCN), conjointly organized by the Argentinian Society of Nutrition and the IUNS Council with an aim to promote the global exchange of knowledge in Nutritional Sciences, held in Buenos Aires, Argentina from October 15-20, 2017.

The objective of this study was to estimate the size and chemical quality of the total organic C stock and its partition between above-belowground plant parts and soil at sites with different plant cover induced by sheep grazing in the arid Patagonian Monte. This study was conducted at six representative sites with increasing signs of canopy disturbance attributed to grazing pressure. We used faeces density as a proxy of grazing pressure at each site. We assessed the total plant cover, shrub and perennial grass cover, total standing aboveground biomass (AGB), litter mass and belowground biomass (BGB) at each site. We further estimated the content of organic C, lignin and soluble phenols in plant compartments and the content of organic C, organic C in humic substances (recalcitrant C) and water soluble C (labile C) in soil at each site. Total plant cover was significantly related to grazing pressure. Standing AGB and litter mass decreased with increasing canopy disturbance while BGB did not vary across sites. Total organic C stock and the organic C stock in standing AGB increased with increasing total plant, shrub, and perennial grass cover. The organic C stock in litter mass increased with increasing total plant and shrub cover, while the organic C stock in BGB did not vary across sites. Lignin content in plant compartments increased with increasing total and shrub cover, while soluble phenols content did not change across sites. The organic C stock and the water soluble C content in soil were positively associated with perennial grass cover. Changes in total plant cover induced by grazing pressure negatively affected the size of the total organic C stock, having minor impact on the size of belowground than aboveground components. The reduction of perennial grass cover was reflected in decreasing chemical quality of the organic C stock in soil. Accordingly, plant managerial strategies should not only be focused on the amount of organic C sequestered but also on the chemical quality of organic C stocks since C chemistry could have an important impact on ecosystem functioning. [ABSTRACT FROM AUTHOR]

Scholarly attention on pension reform following the recent global financial crisis has focused primarily on cases entailing the renationalization of private pension pillars. We argue that radical pension reforms should also include instances of radical retrenchment of public pension pillars. We offer an explanation of such reforms in the aftermath of the crisis by analyzing the reforms adopted in Argentina and Greece since 2008. We demonstrate that highly indebted countries with no access to international financial markets and unsustainable pension systems can introduce radical reforms in response to short-term funding needs rather than long-term adequacy concerns. We argue that the narrow timeframe of the recent reforms raises questions about the sound footing of the new systems which may ultimately not prevent the introduction of further measures. This comparison provides insights to understand recent episodes of radical pension reforms in other countries. Related Articles [ABSTRACT FROM AUTHOR]

Desert shrubs often accumulate different types of phenolic compounds but what determines the amount and diversity of these compounds is an issue scarcely explored. The aim of this study was to assess differences in the amount and diversity of phenolic compounds in leaves among coexisting shrub species differing in rooting depth and leaf turnover. We hypothesized that the diversity and amount of phenolic compounds in leaves of desert shrubs are related to access to soil water through rooting depth, and to leaf turnover. The study was carried out in the Patagonian Monte of Argentina. We collected green leaves of six species representing the dominant shrub morphotypes (tall evergreen, tall deciduous, and medium evergreen shrubs) and assessed lignin concentration and groups of soluble phenols obtained by sequential extraction with ethyl ether, ethyl acetate, and amyl alcohol. We also assessed nitrogen concentration in leaves and leaf mass per unit area (LMA) as traits related to leaf lifespan. The diversity of phenolic compounds was higher in green leaves of tall shrubs with deep rooting depth than in those of medium evergreen shrubs with shallow rooting depth. Diversity of phenolic compounds in green leaves was negatively related to lignin concentration. Evergreen shrubs had higher amount of phenolic compounds in green leaves than deciduous ones and the total amount of phenolic compounds in green leaves was positively related to LMA. We concluded that access to soil water sources and leaf turnover were related to the amount and diversity of phenolic compounds in green leaves of desert shrub species and these results are consistent with those predicted by the resource availability theory for plants from resource-rich and resource-poor habitats. [ABSTRACT FROM AUTHOR]

Arsenic (As) may occur in surface freshwater ecosystems as a consequence of both natural contamination and anthropogenic activities. In this paper, As concentrations in muscle samples of 10 fish species, sediments and surface water from three naturally contaminated rivers in a central region of Argentina are reported. The study area is one of the largest regions in the world with high As concentrations in groundwater. However, information of As in freshwater ecosystems and associated biota is scarce. An extensive spatial variability of As concentrations in water and sediments of sampled ecosystems was observed. Geochemical indices indicated that sediments ranged from mostly unpolluted to strongly polluted. The concentration of As in sediments averaged 6.58 μg/g ranging from 0.23 to 59.53 μg/g. Arsenic in sediments barely followed ( r = 0.361; p = 0.118) the level of contamination of water. All rivers showed high concentrations of As in surface waters, ranging from 55 to 195 μg/L. The average concentration of As in fish was 1.76 μg/g. The level of contamination with As differed significantly between species. Moreover, the level of bioaccumulation of As in fish species related to the concentration of As in water and sediments also differed between species. Whilst some fish species seemed to be able to regulate the uptake of this metalloid, the concentration of As in the large catfish Rhamdia quelen mostly followed the concentration of As in abiotic compartments. The erratic pattern of As concentrations in fish and sediments regardless of the invariable high levels in surface waters suggests the existence of complex biogeochemical processes behind the distribution patterns of As in these naturally contaminated ecosystems. [ABSTRACT FROM AUTHOR]

Two species of Teiichispira Yochelson and Jones reported from the Early/Middle Ordovician marine deposits of the San Juan Formation in the Argentine Precordillera are described. The new species Teiichispira teresae n. sp. is a component of the Early/Middle Ordovician marine gastropod assemblage in the studied region; Teiichispira argentina (Kayser), previously known from the San Juan Formation, is described with a complete teleoconch and associated operculum. The opercula of both Teiichispira species are complete and preserved in life position associated with the shell of T. argentina. The unguiculate morphology of the operculum is here interpreted as a mechanism for increasing the shell weight and ensuring anchoring to the substrate in a more or less fixed mode of life for Teiichispira, and as protection. The new occurrence of Teiichispira provides new taxonomic data on early Paleozoic marine gastropods in Argentina and testifies to a wide paleobiogeographical distribution for the genus, restricted to tropical and subtropical regions during the Early/Middle Ordovician. UUID: http://zoobank.org/8ee48319-b17a-4d15-a7d4-99cc9bb1dc42 [ABSTRACT FROM AUTHOR]

Abstract: The presence of trace elements in water and soils, their absorption by plants, and their transfer to the food chain, is a phenomenon that has been studied in different regions around the world. In Argentina, few studies exist regarding trace element content in soils, and the studies on forages are furthermore scarce. The interest to quantify the levels of trace elements in cattle forage lies in the intrinsic connection between the quality of forage and the nutritional (i.e. Cu and Zn) aspects of cattle health and products for human consumption. Feed lots use feed, which incorporates core minerals whose basic components are Fe, Se, I, Mn, Co, Cu, and Zn. The excess of these trace elements are eliminated through the feces into the environment, therefore, the use of manure from these systems, as a source of organic fertilizer, could reduce environmental contamination, and supplement soils, in areas which are naturally deficient in these micronutrients, for forage growth intended for livestock consumption. Soils from different areas in Argentina were characterized, mainly for their Cu and Zn content. Soil–plant transfer of these trace elements to natural forage was analyzed for agricultural soils with higher content of micronutrients. On the other hand, pot experiments were performed for the enrichment of the forage species, Lolium perenne (ryegrass), with Cu and Zn through fertilization with bovine feces spiked with known concentrations of these trace elements. Soils from copper‐deficient areas used for livestock breeding were used in these experiments. Differences in Cu and Zn concentrations were observed between the fertilized and non-fertilized reactors, while there were no differences found in the Cu and Zn concentrations considering the method of fertilization (homogenization or superficial). These results show that manure from feed lots may be used for forage enrichment with micronutrients. [Copyright &y& Elsevier]

A stenolaemate bryozoan fauna containing 20 species belonging to 18 genera is described from the Las Plantas and Las Aguaditas formations (Upper Ordovician, Sandbian) in San Juan Province, Precordillera of Western Argentina. One genus with one species is new: Argentinodictya lenticulata n. gen. n. sp. (Cryptostomata, Ptilodictyina). Four species are new: one trepostome Parvohallopora parvula n. sp., two cryptostomes Trigonodictya parvula n. sp. and Ptilodictya intermedia n. sp., and phyloporinine Chasmatopora rossae n. sp. The bryozoan assemblage of the Las Plantas Formation is more diverse than that of the Las Aguaditas Formation. Fourteen species are restricted to the Las Plantas Formation, five species occur in both formations, and one species is restricted to the Las Aguaditas Formation. Erect growth forms are dominant in the studied fauna. The majority of bryozoan taxa display palaeobiogeographic relations to Sandbian--Katian deposits of North America, with two species also known from the Katian of Europe. [ABSTRACT FROM AUTHOR]

The aim of this work was to map quantitative trait loci (QTLs) associated with flour yellow color (Fb*) and yellow pigment content (YPC) in durum wheat ( Triticum turgidum L. var. durum). Additionally, QTLs affecting flour redness (Fa*) and brightness (FL*) color parameters were investigated. A population of 93 RILs (UC1113 × Kofa) was evaluated in three locations of Argentina over 2 years. High heritability values (>94%) were obtained for Fb* and YPC, whereas FL* and Fa* showed intermediate to high values. The main QTLs affecting Fb* and YPC overlapped on chromosome arms 4AL (4AL.2), 6AL (6AL.2), 7AS, 7AL, 7BS (7BS.2) and 7BL (7BL.2). The 7BL.1 QTL included the Psy- B1 locus, but one additional linked QTL was detected. A novel minor QTL located on 7AS affected Fb*, with an epistatic effect on YPC. An epistatic interaction occurred between the 7AL and 7BL.2 QTLs. The 4AL.2 QTL showed a strong effect on Fb* and was involved in two digenic epistatic interactions. The 6AL.2 QTL explained most of the variation for Fb* and YPC. The main QTLs affecting FL* and Fa* were located on 2BS and 7BL, respectively. These results confirm the complex inheritance of flour color traits and open the possibility of developing perfect markers to improve pasta quality in Argentinean breeding programs. [ABSTRACT FROM AUTHOR]

This article explores the various claims and class actions involving the Qom people of eastern Formosa Province (Argentina) in recent years. In order to do so, it addresses their involvement in the struggle of small-scale peasant farmers. Discussing the protests led by the Movimiento Campesino de Formosa in 2005, the paper goes on to explore the forms, meanings and determinations of the indigenous movement. [ABSTRACT FROM AUTHOR]

Selective sheep grazing in arid rangelands induces a decrease in total cover and grass cover and an increase in the dominance of shrubs. Both life forms differ in aboveground and belowground traits. We hypothesized that grazing disturbance leads to the replacement of grass by shrub fine roots in the upper soil, and this is reflected in changes in the seasonal dynamics of shallow fine roots at the community level. In two sites representative of non-grazed and grazed vegetation states in the Patagonian Monte, we assessed the canopy structure, and the fine root biomass, N concentration, production, and turnover during two consecutive years. The non-grazed site exhibited higher total, grass, and shrub cover than the grazed site. The grazed site had larger or equal fine root biomass than the non-grazed site except for late spring of the second year. This could be associated with the ability of shrubs to develop dimorphic-root systems occupying the soil freed by grasses at the grazed site, and with the larger contribution of grass than shrub fine roots in relation to an extraordinary precipitation event at the non-grazed site. This was consistent with the N concentration in fine roots. Fine root production was positively correlated to temperature at the grazed site and with precipitation at the non-grazed site. Fine root turnover did not differ between sites. Our results indicate that grazing leads to a shifting in the seasonality and main climatic controls of fine root production, while fine root turnover is mostly affected by changes in soil water conditions. [ABSTRACT FROM AUTHOR]

This article discusses the role of general stores in Buenos Aires, Argentina, during the country's war of independence from Spain in the second decade of the 19th century. It examines the prevalence of banditry, including raids of general stores by federal troops as a method of obtaining resources and money. The author studies tax registers from this time period and analyzes the tax exemption provided to the general store owners. The impact of these military raids on the commercial industry and on retail traders both during and after the war is also explored.

Copyright of Intersecoes: Revista de Estudios Interdisciplinares is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) 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.)

Wild sunflower Helianthus annuus originates from North America and has naturalised in Argentina where it is considered invasive. The present study attempts to assess the genetic diversity using two different molecular marker systems to study the wild genetic patterns and to provide data applicable to conservation and breeding uses. Ten natural populations sampled throughout the wild range and six inbred lines were studied using inter-simple sequence repeat (ISSR) and simple sequence repeats (SSR) markers. A total of 64 ISSR bands and 29 SSR alleles were produced from 106 wild and cultivated plants. We found 9 ISSR private bands and 21 SSR private alleles in wild accessions, but no private bands/alleles were found in cultivated sunflowers. Molecular variability in wild populations was approximately 60% higher than in inbred lines. Local wild sunflowers kept considerable diversity levels in comparison with populations in the centre of origin (approximately 70%) and therefore they might possess a potential for adaptive evolutionary change. Analysis of molecular variance (AMOVA) indicated population structure with nearly 20% of genetic variability attributable to between-population differentiation. Principal coordinate analyses (PCO) grouped wild populations from different geographic locations, and a Mantel test showed low congruence between genetic distance (GD) and geographic distances (GGD); hence, molecular data could not rule out multiple wild introduction events. Low correlations were found between ISSR and SSR GD at individual and population levels; thus, divergent evolutionary groups were not evident in local wild sunflowers. Several genetic diversity criteria were utilised to assign conservation value and certain wild populations emerged as interesting sites for more extensive sampling. [ABSTRACT FROM AUTHOR]

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

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag 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.)

Abstract: This paper presents a new method for the 3D reconstruction of geological structures: the equivalent dip domain method. It improves existing and currently used methods of structural reconstruction by taking advantage of the absolute position of dip data and by imposing geological constraints derived from the structural analysis of data. It deals with the definition of the simplest 3D geometry that honours most of the data; in the case presented here this geometry has been simplified to multiple cylindrical domains. The geometric framework derived from these cylindrical domains (fold axis and different planes) enables the interpolation and extrapolation of dip data along the structure to fill gaps of information. Thus, this method is useful to reconstruct the 3D geometry of structures in which available data are scarce and/or sparse. This method has been developed to reconstruct the 3D geometry of structures in remote areas where data acquisition is not always possible. It has been applied to the reconstruction of the Cerro Bayo Anticline, a thrust-related fold of the Cordillera Oriental in the north-western Argentine Andes. There, the analysis of aerial and satellite images and its combination with field data add further constraints in the definition of the geometrical framework. [Copyright &y& Elsevier]

Se analizaron egagrópilas de dos especies de Strigiformes para conocer la constitución específica de las comunidades de micromamíferos de tres localidades del centro-oeste de Mendoza, Argentina. Las localidades de Las Leñas y Laguna El Sosneado se encuentran ubicadas en la Provincia Fitogeográfica Patagónica, en el ecotono con la Provincia Altoandina; mientras que Gruta del Indio se encuentra en la Provincia del Monte. La comunidad correspondiente a Gruta del Indio está conformada principalmente por micromamíferos adaptados a ambientes xéricos del desierto del Monte (e. g., Eligmodontia sp., Calomys musculinus, Graomys griseoflavus y Akodon molinae). En las comunidades pertenecientes a las localidades de Laguna El Sosneado y Las Leñas se observaron elementos frecuentes de las estepas Patagónica y Altoandina (e. g., Euneomys chinchilloides, Abrothrix olivaceus, Chelemys macronyx). Sin embargo, las comunidades de estas dos últimas localidades presentaron algunas diferencias entre sí, las cuales podrían deberse a los distintos tipos de microhábitats presentes en las mismas y a la ubicación más occidental de Las Leñas. [ABSTRACT FROM AUTHOR]

Abstract: In arid and semiarid ecosystems, primary productivity and nutrient cycling are directly related to the amount and seasonal distribution of precipitation. However, depending on morphological, phenological, physiological, and biochemical traits, plants may influence the quality and quantity of organic matter inputs to the soil and thus the biomass and activity of the soil biota responsible for carbon and nitrogen dynamics. In this paper, we review the available knowledge on plant functional traits and their impacts on ecosystem processes such as N and C cycling throughout the Monte Phytogeographical Province. We address the mechanisms of N conservation, the quantity and quality of leaf litterfall and root traits of the dominant plant life forms and their effects on decomposition processes, soil organic matter accretion, and soil-N immobilization and mineralization. We conclude that plant functional traits affect ecosystem processes in the Monte Phytogeographical Province since the chemistry of senesced leaves and root biomass exerts an important control on organic matter decomposition and N availability in soil. [Copyright &y& Elsevier]

Abstract: Growth strata and unconformities in the Cenozoic synorogenic sediments in the southern Cordillera Oriental of the northern Argentine Andes provide new evidence for the eastward migration of the Andean deformation from the Puna to the Santa Bárbara system. The growth sequences and unconformities allow us to constrain the age of the structures with greater precision and to determine the distribution of this deformation in the thrust and fold wedge over time. Thrust evolution was mainly controlled by the reactivation of earlier extensional faults of the Cretaceous Salta Rift Basin. The geometry of the inverted structures together with the general forward migration of the deformation gave rise to different thrust sequences. The foreland dipping imbricate stack of the western Cordillera Oriental developed forwards during Middle–Late Miocene, resulting in a break back thrusting sequence. Thrust propagation rate increased in Late Miocene-Early Pliocene times when the eastern part of the Cordillera Oriental developed. At that time a widespread deformation and synchronous thrusting occurred in the Cordillera Oriental. Subsequently, deformation was mainly confined to the eastern part of the Cordillera Oriental. Finally, during the Pleistocene-Holocene, deformation affected a wider zone, including the Cordillera Oriental and the Santa Bárbara System, giving rise to the reactivation of previously developed thrusts. [Copyright &y& Elsevier]

Selective sheep grazing in the Patagonian Monte induces the reduction of total and perennial grass cover, species replacement within life forms, and the increase in dominance of long-lived evergreen woody plants with slow growth rates and high concentration of secondary compounds in leaves. We hypothesized that these changes in the canopy structure induced by sheep grazing will affect the mass, chemistry and decomposability of leaf litter and fine roots. We selected two sites in the Patagonian Monte, representative of ungrazed and grazed vegetation states. At each site, we assessed canopy structure (total cover and absolute and relative grass and shrub cover), monthly leaf litterfall, and fine-root biomass and production in the upper soil (15 cm). We also estimated the rates of mass, C, soluble phenolics, lignin and N decay in litterbags containing both leaf litter and fine roots of each site under field conditions during two consecutive years. The ungrazed site exhibited higher total plant cover, absolute and relative grass- and shrub-cover than the grazed one. Leaf litterfall was lower at the grazed site than at the ungrazed site. Fine-root production did not vary between sites. Leaf litter and fine root tissues had higher concentration of secondary compounds at the grazed than at the ungrazed site. However, fine roots showed lower mass and C decay than leaf litter, attributable to the predominant secondary compound (lignin and soluble phenolics, respectively). Leaf litter decomposed slower but released more N during decay at the ungrazed than at the grazed site, probably due to its low concentration of secondary compounds. We concluded that changes in canopy structure induced by grazing disturbance such as those explored in our study could reduce leaf litterfall mass and increase the concentration of secondary compounds of both leaf litter and fine roots leading to slow N release to soil during decay. [ABSTRACT FROM AUTHOR]

Two new bryozoan species are described from the Upper Ordovician Sassito Formation of the Argentinean Precordillera: Moyerella  spinata sp. nov. and Phylloporina  sassitoensis sp. nov. The bryozoans are found in cool-water carbonates. The Silurian genus Moyerella is reported the first time in the Ordovician, showing palaeobiogeographic connections with Estonia and Siberia. [ABSTRACT FROM AUTHOR]

Abstract: Naturalized populations of wild sunflower, Helianthus annnus, occur in six provinces of central Argentina, usually near sunflower crops. Plants of intermediate morphology indicate that gene flow might take place in both senses. In order to quantify gene flow between cultivated and wild sunflower, an experimental stand of sunflower was sown surrounded by plots of wild plants at increasing distances. Hybridization rate was estimated using a crop specific isozyme marker, and a mean of 7% progenies were crop-wild hybrids. The nearest wild plants (3m from the cultivar) showed the highest percentage (18%) of gene flow, which was found to decrease with distance, up to 500m. Pollen flow from wild plants to crop, evaluated through morphological characters in the progenies of cultivated plants from a stand invaded by wild sunflowers, produced 3.75% intermediate plants. [Copyright &y& Elsevier]

The article presents an analysis of Argentina's rising economy growth due to its high commodity prices. The high liquidity in the world market reportedly pushes the demand for Argentina's export products to a high level which have increased its share in investment fund portfolios. It points out that economic growth results in good governance. It recommends that countries like Argentina should take advantage of the current high prices to minimize cost of future reversion.

Dairy cattle drinking water in 28 medium and small farms located in the southeast of Cordoba province, Argentina, was analyzed in order to assess its beneficial and adverse effect in milk production. Total dissolved solids (TDS), major ions, nitrates and trace metals were quantified by standardized methods. Water from the phreatic level is used in 62% of the selected farms, being its quality lower than that provided by deeper wells. Sodium chloride and sulfur requirements are provided by drinking water. Arsenic, fluoride and vanadium concentrations found in all phreatic samples are higher than the maximum allowed values recommended at international level. [ABSTRACT FROM AUTHOR]

Abstract: The Salta Basin of Cretaceous age in the Andes of NW Argentina was inverted during the development of the Cordillera Oriental between the Neogene and Recent. The different orientations of the extensional faults of the Salta Rift System and the subsequent W-E shortening resulted in a great variety of inversion structures. Extensional faults dipping NE to ESE were preferentially reactivated as contractional faults. The initial stepped geometry of these faults gave rise to a distinctive sigmoidal pattern of basement-involved thrusts and related folds. These contractional structures tended to run parallel to the extensional faults and acquired a N-S trend across the previous accommodation zones, resulting in folding interference patterns. Other interference patterns are attributed to the superposition of contractional folds on previous rollovers and to the constrictional deformation imposed by the reactivation of adjacent extensional faults with different orientations. The NNW to WSW dipping extensional faults show no evidence of reactivation despite the fact that some of them are folded. The inversion at crustal scale is limited owing to the presence of the Cretaceous Salta Rift across the different Andean structural units and foreland. [Copyright &y& Elsevier]

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In two consecutive years, we analysed the effect of litter quality, quantity and decomposability on soil N at three characteristic sites of the Patagonian Monte. We assessed (i) concentrations of N, C, lignin and total phenolics and the C/N ratio in senesced leaves as indicators of litter quality of three species of each dominant plant life form (evergreen shrubs and perennial grasses), and (ii) N, and organic-C concentrations, potential N-mineralisation and microbial-N flush in the soil beneath each species. Rate constants of potential decomposition of senesced leaves and N content in decaying leaves during the incubation period were assessed in composite samples of the three sites as indicators of litter decomposability. Further, we estimated for each species leaf-litter production, leaf-litter on soil, and the mass of standing senesced leaves during the senescence period. Senesced leaves of evergreen shrubs showed higher decomposability than those of perennial grasses. Leaf-litter production, leaf-litter on soil, and the mass of standing senesced leaves differed significantly among species. The largest variations in leaf-litter production and leaf-litter on soil were observed in evergreen shrubs. The mass of standing senesced leaves was larger in perennial grasses than in evergreen shrubs. Nitrogen, organic C and potential N-mineralisation in soil were higher underneath evergreen shrubs than beneath perennial grasses, while no significant differences were found in microbial-N flush among life forms. The initial concentrations of C, N and total phenolics of senesced leaves explained together 78% of the total variance observed in the dry mass loss of decaying leaves. Litter decomposition rates explained 98%, 98%, 73%, and 67% of the total variance of soil N, organic C, net-N mineralisation, and microbial-N flush, respectively. We concluded that leaf-litter decomposition rates along with leaf-litter production are meaningful indicators of plant local effects on soil N dynamics in shrublands of the Patagonian Monte, and probably in other similar ecosystem of the world dominated by slow growing species that accumulate a wide variety of secondary metabolites including phenolics. Indicators such as C/N or lignin concentration usually used to predict litter decomposability or local plant effects may not be adequate in the case of slow growing species that accumulate a wide range of secondary metabolites or have long leaf lifespan and low leaf-litter production. [ABSTRACT FROM AUTHOR]

During three consecutive years with contrasting precipitation, we analysed the relationship between strategies of N conservation in the dominant plant functional groups (perennial grasses and evergreen shrubs) of the Patagonian Monte and the main components of N cycling in soil. We hypothesised that the different patterns of N conservation in perennial grasses and evergreen shrubs would have direct consequences for soil-N, inorganic-N release and microbial-N flush in soil. In autumn and late spring of 1999, 2000, and 2001, we assessed N and C concentration in green and senesced leaves, N-resorption efficiency and C/N ratio in senesced leaves of three dominant species of each plant functional group. In the soil associated with species of each plant functional group, we determined N and C concentration, potential-N mineralisation, and the associated microbial-N flush. Slow-growing evergreen shrubs exhibited low N-concentration in green leaves, high N-concentration in senesced leaves and low N-resorption from senescing leaves. In contrast, fast-growing perennial grasses showed high N-concentration in green leaves, low N-concentration in senesced leaves, and high N-resorption from senescing leaves. In evergreen shrubs, the maintenance of long-lasting green leaves with low N-concentration was the most important mechanism of N conservation. In contrast, perennial grasses conserved N through high N-resorption from senescing leaves. Soil-N concentration, potential N-mineralisation, and microbial-N flush in the soil were higher underneath evergreen shrubs than beneath perennial grasses. Observed differences, however, were lower than expected considering the quality of the organic matter supplied by each plant fuctional group to the soil. A possible reason for this relatively weak trend may be the capacity of evergreen shrubs to slow down N cycling through low leaf turnover and the presence of secondary compounds in leaves. Alternatively or simultaneously, the weak relationship between plant and soil N could result from shrubs being able to colonise N-poor soils while grasses may preferably occupy fertile microsites previously influenced by the decomposition pathway of evergreen shrubs. Differences between evergreen shrubs and perennial grasses in the mechanisms of plant N-conservation and in components of N cycling in the underlying soil were consistent over the three years of the study with differing precipitation. Inter-annual differences in N concentration in green leaves and in the microbial-N flush in soil indicate that during the wettest year fast-growing perennial grasses would outcompete slow-growing evergreen shrubs and microorganisms for N uptake. [ABSTRACT FROM AUTHOR]

The Grupo de Empresas Farmacéuticas Sidus is an Argentine Business Group with a leading role in contributing to an upgrade within the country's pharmaceutical sector. The organization has successfully faced the evolutionary challenges of this changing sector, in addition to having implemented a thorough internationalization process based on technological innovation. The Argüelles family founded the company in 1938. In the early 1980s the company envisioned the prominent role to be played by biotechnology and created Bio Sidus S.A., so as to concentrate resources on research and development. Throughout its history, the Grupo de Empresas Farmacéuticas Sidus has made continuous investments in research, equipment, technology, and human resources. Currently, it is the third-largest producer in the Argentine pharmaceutical sector being the owner of the three most modern production plants of their kind in Latin America. Today, 65 years after its birth, the group is managed by the second generation of the Argüelles family. Marcelo Argüelles, CEO and chairman, leads a team of 900 professionals, including scientists, technicians, marketing experts, and administrative personnel, all of whom have been the recipients of constant training investments by the company. As for Bio Sidus S.A., after twenty years in operation, it has become a leading organization in its field. Such leadership is based on an efficient integration of business, science, and technology. The company sells six types of protein, not only in the local market but also in more than 30 other countries. Bio Sidus S.A. also has over ten molecules under development and is taking the first steps in such scientific fields as vegetal and animal biotechnology and chemical synthesis. The firm has leveraged its own technology to generate biotechnological raw materials in Argentina. It has successfully integrated science and industry through research agreements with government and private institutions oi both national and international origin. The company has also leveraged a biomedi cine-exporter profile based on quality products and international competitiveness. The motto of the company is "Progress with science." [ABSTRACT FROM AUTHOR]

Argentine economic history can be pictured as a series of severe economic ups and downs, which created unique managerial challenges for growing businesses. In this article we show how Argentine entrepreneurs have successfully crafted strategies and organizational forms to cope with this economic "roller coaster." Our work is founded on the resource-based view, state development and market-failure theories, and relies on data from historical evidence, surveys, and thorough interviews with CEOs of the largest Argentine firms--known as Argentine Business Groups (ABGs). We found that ABGs generally expanded their corporate portfolios in periods of higher uncertainty by skillfully maneuvering through labor and capital market deficiencies and leveraging preferred foreign and local contacts and opportunities. We also found that in response to the Argentine market-oriented reforms of the 1990s, many ABGs trimmed their business portfolios and expanded internationally to compete more effectively. As for the recent economic turmoil, internationally diversified ABGs who relied more heavily on managerial teams with local expertise had a competitive advantage over ABGs with an exclusive local market focus or even multinational subsidiaries relying on international managerial teams. We derive lessons for firms managing businesses in similar environments and those wishing to reap opportunities in Argentina. [ABSTRACT FROM AUTHOR]

In patchy environments of arid Patagonia, males of the dioecious grass Poa ligularis dominate in N-poor microsites, while females are more common in N-rich microsites. In order to explore functional differences related to spatial segregation of the sexes, we analyzed biomass allocation and tissue N concentration in males and females of P. ligularis growing in a range of soil N concentrations (sN). Based on the general patterns of responses described for plants from N-rich and N-poor habitats, we hypothesized that (1) females, which dominate in N-rich microsites, would increase biomass allocation with increasing sN, while males, frequent in N-poor microsites, would show a limited response and (2) tissue N concentration would display a wider variation in males than females in response to changes in sN. At three sites in northern Patagonia, we randomly selected 15 plants of each sex of P. ligularis growing inside shrub patches and 15 in the interpatch areas and evaluated the biomass and N concentration of aboveground (vegetative and reproductive) and belowground structures. Biomass allocation to belowground structures and N concentration in roots increased with in-creasing sN for both males and females. Aboveground biomass increased with increasing sN only in females. In the N-poorest sites, we found higher N allocation to tiller crowns with increasing sN in males relative to females. In both sexes, biomass allocation to sexual reproductive structures (panicles) did not change signif-icantly with variations in sN. These results provide partial evidence on morphological and functional dimor-phism in a dioecious species with spatial segregation of the sexes. Keywords: biomass allocation, dioecy, nitrogen concentration in plant tissues, nitrogen concentration in roots, nitrogen gradients in soil, spatial segregation of the sexes. [ABSTRACT FROM AUTHOR]

The article presents a study which determines the microvertebrates preyed upon by the pampas cat or Leopardus pajeros, a small South American felid with a broad geographic distribution, in southern Mendoza Province, Argentina. The study includes the assignment of feces to felid species by bile-acid analysis. Result of the study reveals that Pampas cat or Leopardus pajeros cat preyed upon lizards, birds, and rodents, which majority represented by cricetids, followed in importance by tuco-tucos or Ctenomys.

New linguliform microbrachiopods from the Middle Ordovician are described and illustrated. This fauna was recovered from the uppermost beds of the San Juan Formation in two sections of the Central Precordillera (Argentina), which are accurately dated to the Lenodus pseudoplanus Zone (middle Darriwilian). The fauna consists of the obolid Luthieria diminuta n. gen. n. sp., and the acrotretids Eoconulus tucunucoensis n. sp., Conotreta andina Lavié, Serra, and Feltes, Scaphelasma zharykensis Popov, and Numericoma rowelli Holmer et al. This low-diversity lingulate association displays close similarities with coeval faunas that inhabited the Laurentia, Baltica, and Kazakhstanian regions, in agreement with evidence from other linguliform and rhynchonelliform brachiopods. UUID: http//zoobank.org/fe9acbb0-6654-4462-ba4d-ea2386ae79f6 [ABSTRACT FROM AUTHOR]

Abstract: Grazers exert important effects on the plant–soil system influencing the structure and functioning of the ecosystems. The effect of grazing on soil enzyme and microbial activities in arid ecosystems of the Patagonian Monte (Argentina) was studied by assessing the cover of plant life forms (grasses, shrubs and dwarf shrubs) at five modal plant-covered patches at three sites across a grazing gradient. We hypothesized that grazing mostly affects negatively soil enzyme and microbial activities through its effect on vegetation and on soil chemical and physical parameters. Soil cores were extracted from plant-covered patches and associated inter-canopy areas and analyzed the chemical (organic-C, total-N and pH), physical (bulk density), microbial (microbial biomass-C, and heterotrophic microorganism counts), and enzyme (dehydrogenase, ß-glucosidase, protease, alkaline and acid phosphatase and the geometric media for these activities) soil properties. Grass and dwarf shrub covers declined, and soil pH and bulk density increased with increasing grazing intensity at plant patches and inter-canopy areas. Soil organic-C and soil-N decreased at plant patches and, were positively correlated to grass cover. Soil organic-C was also positively correlated with ß-glucosidases and phosphatases, indicating that a reduction in soil organic-C could be associated with low enzyme activity and consequently with low soil organic matter turnover and nutrient release. Negative effects of grazing on enzyme activities were also detected on protease activity at inter-canopy areas and geometric media of the enzyme activities at plant patches. Increasing grazing intensity was associated with increasing values of microbial biomass-C and heterotrophic microorganism counts mostly at inter-canopy areas, suggesting that inputs of labile N by urine and dung may partially counteract the negative grazing effects. We concluded that grazing mostly affected soil physicochemical and biological parameters through direct and indirect effects of trampling and urine and changes in perennial grass cover, respectively. [Copyright &y& Elsevier]

This paper is part of a broader research project focused on analyzing rockshelters and shallow caves located in different regions and geological contexts in Argentina. The main goal is to evaluate patterns and peculiarities in the development of their morphologies and stratigraphies from a geoarchaeological perspective. These sites provide restricted environments with particular dynamics that form, evolve, fill up, and collapse in many different ways that need to be studied at a regional scale to interpret the archaeological and taphonomic records they contain. In one same area, these geoforms can be found at different steps of evolution; but the velocity of this change process, as well as their characteristics, are poorly known for different regions of the country. Thus, 24 case studies, located in different areas, are analyzed in this contribution to start evaluating patterns and recurring processes. So far, some interesting regularities have been observed, regarding the sites themselves (morphologies, types, and dimensions) as well as their sedimentary deposits (characteristics and chronologies). The preliminary results obtained, begin to offer useful information for their archaeological and taphonomic interpretation. [ABSTRACT FROM AUTHOR]