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The development of groundwater resources sustainability indicators is a process of scientific approach that presents the different characteristics of the groundwater systems in a simplified and understandable way. Although its use in such a system is relatively recent, their proper selection provides a valid basis to support coordinated actions in the process of resource operation, planning and management. The central area of Santa Fe province, Argentina, is one of the main producing regions of the province and the country, standing out for its dynamism in both the economic and socio-cultural aspects. In particular, the study area is characterized by strong agriculture-farming and industry activities. The grain and oilseed production has great preponderance in this area, which is complemented by dairies, meat and tanneries strengthened by the presence of the livestock sector. It also highlights the timber ventures, fine furniture stores, and provision of industrial and food systems. The natural quality of groundwater and the scarcity of exploitable surface water resources make groundwater exploited as the exclusive source of supply. This paper focusses on the use of groundwater sustainability indicators in an area of the Santa Fe province, Argentina, where groundwaters are the only source of supply to satisfy the demand for the various purposes. From the indicators used, the indicators of groundwater abstraction demonstrated that local recharge rate is not sufficient to meet the current demand in the area. Therefore, the identification of these indicators incorporates the high added value that they offer as a synthetic measure for the sustainability of groundwater exploitation. Besides, it is expected that the selected indicators contribute to the evaluation of the management of these water resources, to the development of new shares and/or the establishment of plans and projects for their proper management. [ABSTRACT FROM AUTHOR]

In this paper we summarize for the first time the effects of agriculture expansion and intensification on animal diversity in the Pampas of Argentina and discuss research needs for biodiversity conservation in the area. The Pampas experienced little human intervention until the last decades of the 19th century. Agriculture expanded quickly during the 20th century, transforming grasslands into cropland and pasture lands and converting the landscape into a mosaic of natural fragments, agricultural fields, and linear habitats. In the 1980s, agriculture intensification and replacement of cattle grazing-cropping systems by continuous cropping promoted a renewed homogenisation of the most productive areas. Birds and carnivores were more strongly affected than rodents and insects, but responses varied within groups: (a) the geographic ranges and/or abundances of many native species were reduced, including those of carnivores, herbivores, and specialist species (grassland-adapted birds and rodents, and probably specialized pollinators), sometimes leading to regional extinction (birds and large carnivores), (b) other native species were unaffected (birds) or benefited (bird, rodent and possibly generalist pollinator and crop-associated insect species), (c) novel species were introduced, thus increasing species richness of most groups (26% of non-rodent mammals, 11.1% of rodents, 6.2% of birds, 0.8% of pollinators). Much taxonomic and ecological work is still needed to understand Pampean animal biodiversity, to understand how agriculturization is affecting it, and to identify appropriate conservation actions. Networks of Important Bird Areas and Valuable Grassland Areas harbor a balanced representation of Pampean biodiversity and, if adequately protected, may provide valuable research sites, but complementary work should be carried out on agriculturized areas. [ABSTRACT FROM AUTHOR]

The rare but important phenomenon of business protest has not been adequately addressed in either literature on contentious politics or literature on business politics. Using Argentina's 2008 agricultural producers' protests as an illustration, this paper develops the concept of business protest and situates it within the classic framework of business' instrumental power, exercised through political actions, and structural power, arising from individual profit-maximizing behavior. Business protest entails public and/or disruptive collective action in either the economic arena or the societal arena. Business actors are most likely to consider protest in order to defend their core interests when their structural power is weak and when they lack sources of instrumental power that enhance the effectiveness of ordinary political actions like lobbying. I apply the business power and protest framework to explain the Argentine producers' failure to influence export tax policy from 2002 through early 2008 and the emergence of protest against a 2008 tax increase. I then examine how the producers' protests contributed to the reform's repeal. The producers' protests are an exceptional example of business protest in which the participants lacked key organizational resources that facilitate collective action. [ABSTRACT FROM AUTHOR]

Tephra fall from the August 1991 eruption of Volcán Hudson affected some 100,000 km of Patagonia and was almost immediately reworked by strong winds, creating billowing clouds of remobilised ash, or 'ash storms'. The immediate impacts on agriculture and rural communities were severe, but were then greatly exacerbated by continuing ash storms. This paper describes the findings of a 3-week study tour of the diverse environments of southern Patagonia affected by ash storms, with an emphasis on determining the impacts of repeated ash storms on agriculture and local practices that were developed in an attempt to mitigate these impacts. Ash storms produce similar effects to initial tephra eruptions, prolonged for considerable periods. These have included the burial of farmland under dune deposits, abrasion of vegetation and contamination of feed supplies with fine ash. These impacts can then cause problems for grazing animals such as starvation, severe tooth abrasion, gastrointestinal problems, corneal abrasion and blindness, and exhaustion if sheep fleeces become laden with ash. In addition, ash storms have led to exacerbated soil erosion, human health impacts, increased cleanup requirements, sedimentation in irrigation canals, and disruption of aviation and land transport. Ash deposits were naturally stabilised most rapidly in areas with high rainfall (>1,500 mm/year) through compaction and enhanced vegetation growth. Stabilisation was slowest in windy, semi-arid regions. Destruction of vegetation and suppression of regrowth by heavy tephra fall (>100 mm) hindered the stabilisation of deposits for years, and reduced the surface friction which increased wind erosivity. Stabilisation of tephra deposits was improved by intensive tillage, use of windbreaks and where there was dense and taller vegetative cover. Long-term drought and the impracticality of mixing ash deposits with soil by tillage on large farms was a barrier to stabilising deposits and, in turn, agricultural recovery. The continuing ash storms motivated the partial evacuation of small rural towns such as Chile Chico (Chile) and Los Antiguos (Argentina) in September-December 1991, after the primary tephra fall in August 1991. Greatly increased municipal cleanup efforts had to be sustained beyond the initial tephra fall to cope with the ongoing impacts of ash storms. Throughout the 1990s, ash storms contributed to continued population migration out of the affected area, leaving hundreds of farms abandoned on the Argentine steppe. The major lesson from our study is the importance of stabilisation of ash deposits as soon as possible after the initial eruption, particularly in windy, arid climates. Suggested mitigation measures include deep cultivation of the ash into the soil and erecting windbreaks. [ABSTRACT FROM AUTHOR]

Background, aim and scope Regional specificities are a key factor when analyzing the environmental impact of a biofuel pathway through a life cycle assessment (LCA). Due to different energy mixes, transport distances, agricultural practices and land use changes, results can significantly vary from one country to another. The Republic of Argentina is the first exporter of soybean oil and meal and the third largest soybean producer in the world, and therefore, soybean-based biodiesel production is expected to significantly increase in the near future, mostly for exportation. Moreover, Argentinean biodiesel producers will need to evaluate the environmental performances of their product in order to comply with sustainability criteria being developed. However, because of regional specificities, the environmental performances of this biofuel pathway can be expected to be different from those obtained for other countries and feedstocks previously studied. This work aims at analyzing the environmental impact of soybean-based biodiesel production in Argentina for export. The relevant impact categories account for the primary non-renewable energy consumption (CED), the global warming potential (GWP), the eutrophication potential (EP), the acidification potential (AP), the terrestrial ecotoxicity (TE), the aquatic ecotoxicity (AE), the human toxicity (HT) and land use competition (LU). The paper tackles the feedstock and country specificities in biodiesel production by comparing the results of soybean-based biodiesel in Argentina with other reference cases. Emphasis is put on explaining the factors that contribute most to the final results and the regional specificities that lead to different results for each biodiesel pathway. Materials and methods The Argentinean (AR) biodiesel pathway was modelled through an LCA and was compared with reference cases available in the ecoinvent® 2.01 database, namely, soybean-based biodiesel production in Brazil (BR) and the United States (US), rapeseed-based biodiesel production in the European Union (EU) and Switzerland (CH) and palm-oil-based biodiesel production in Malaysia (MY). In all cases, the systems were modelled from feedstock production to biodiesel use as B 100 in a 28 t truck in CH. Furthermore, biodiesel pathways were compared with fossil low-sulphur diesel produced and used in CH. The LCA was performed according to the ISO standards. The life cycle inventory and the life cycle impact assessment (LCIA) were performed in Excel spreadsheets using the ecoinvent® 2.01 database. The cumulative energy demand (CED) and the GWP were estimated through the CED for fossil and nuclear energy and the IPCC 2001 (climate change) LCIA methods, respectively. Other impact categories were assessed according to CML 2001, as implemented in ecoinvent. As the product is a fuel for transportation (service), the system was defined for one vehicle kilometre (functional unit) and was divided into seven unit processes, namely, agricultural phase, soybean oil extraction and refining, transesterification, transport to port, transport to the destination country border, distribution and utilisation. Results The Argentinean pathway results in the highest GWP, CED, AE and HT compared with the reference biofuel pathways. Compared with the fossil reference, all impact categories are higher for the AR case, except for the CED. The most significant factor that contributes to the environmental impact in the Argentinean case varies depending on the evaluated category. Land provision through deforestation for soybean cultivation is the most impacting factor of the AR biodiesel pathway for the GWP, the CED and the HI categories.… [ABSTRACT FROM AUTHOR]

Azospirillum is one of the most studied plant growth-promoting bacteria (PGPB); it represents a common model for plant-bacterial interactions. While Azospirillum brasilense is the species that is most widely known, at least 22 species, including 17 firmly validated species, have been identified, isolated from agricultural soils as well as habitats as diverse as contaminated soils, fermented products, sulfide springs, and microbial fuel cells. Over the last 40 years, studies on Azospirillum-plant interactions have introduced a wide array of mechanisms to demonstrate the beneficial impacts of this bacterium on plant growth. Multiple phytohormones, plant regulators, nitrogen fixation, phosphate solubilization, a variety of small-sized molecules and enzymes, enhanced membrane activity, proliferation of the root system, enhanced water and mineral uptake, mitigation of environmental stressors, and competition against pathogens have been studied, leading to the concept of the Multiple Mechanisms Hypothesis. This hypothesis is based on the assumption that no single mechanism is involved in the promotion of plant growth; it posits that each case of inoculation entails a combination of a few or many mechanisms. Looking specifically at the vast amount of information about the stimulatory effect of phytohormones on root development and biological nitrogen fixation, the Efficient Nutrients Acquisition Hypothesis model is proposed. Due to the existence of extensive agriculture that covers an area of more than 60 million hectares of crops, such as soybeans, corn, and wheat, for which the bacterium has proven to have some agronomic efficiency, the commercial use of Azospirillum is widespread in South America, with over 100 products already in the market in Argentina, Brazil, and Uruguay. Studies on Azospirillum inoculation in several crops have shown positive and variable results, due in part to crop management practices and environmental conditions. The combined inoculation of legumes with rhizobia and Azospirillum (co-inoculation) has become an emerging agriculture practice in the last several years, mainly for soybeans, showing high reproducibility and efficiency under field conditions. This review also addresses the use of Azospirillum for purposes other than agriculture, such as the recovery of eroded soils or the bioremediation of contaminated soils. Furthermore, the synthetic mutualistic interaction of Azospirillum with green microalgae has been developed as a new and promising biotechnological application, extending its use beyond agriculture. [ABSTRACT FROM AUTHOR]

The Pampean region covers a large surface in central Argentina, but despite the extensive agricultural activities and the high nutrient levels recorded in streams of the region, few authors have analysed the influence of land use on water quality. Here, we evaluated the relationships among catchment attributes (size, morphometry and land cover) and water chemistry in 23 Pampean streams in different seasons (autumn, spring and summer) and at three spatial scales: whole catchment and two scales of riparian buffers (200 and 500 m adjacent to both stream margins). Chloride concentration was positively related to catchment area and negatively related to drainage density. Nitrate level was strongly associated to cropland, but soluble phosphorus concentration showed no relationships with any type of land cover. Land cover at the buffer scale seemed to be more influential than land cover at the whole catchment for nitrogen concentration. The main impact of cropland was the increase of nitrate concentration, while cattle breeding was negatively associated to photosynthetically active radiation (PAR) in autumn and summer and to dissolved oxygen concentration in spring. Our results highlighted the importance of local land use and riparian conservation on streamwater quality. [ABSTRACT FROM AUTHOR]

Woody plant-cover dynamics can alter the provisioning of ecosystem services that humans rely on. However, our understanding of such dynamics today is often limited by the availability of reliable and detailed land-cover information in the past, before the onset of remote sensing technologies. In this study, we carefully extracted information from historical maps of the Caldenal savannas of central Argentina in the 1880s to generate a woody cover map that we compared to a 2000s dataset. Over about the last 120 years, woody cover increased across approximately 12,200 km (14.2% of the area). During the same period, about 5,000 km of the original woody area was converted to croplands and around 7,000 km to pastures, about the same total land area as was affected by encroachment. A smaller area, fine-scale analysis between the 1960s and the 2000s revealed that tree cover increased overall by 27%, shifting from open savannas to a mosaic of dense woodlands along with additional agricultural clearings. Statistical models indicate that woody cover dynamics in this region were affected by a combination of environmental and human factors. Over about the last 120 years, increases in woody plant cover have stored significant amounts of C (95.9 TgC), but not enough to compensate for losses from conversions to croplands and pastures (166.7 TgC), generating a regional net loss of 70.9 TgC. C losses could be even larger in the future if, as predicted, energy crops such as switchgrass, would trigger a new land-cover change phase in this region. [ABSTRACT FROM AUTHOR]

Patterns of land-use and land-cover change are usually grouped into one of two categories defined by the dominant trend: (1) deforestation resulting from expanding agriculture and (2) forest expansion, usually related to the abandonment of marginal lands. At regional scale, however, both processes can occur simultaneously even in the absence of net change. Given the focus on net change, such redistribution of agricultural and natural and seminatural lands has been generally overlooked. The interaction between agriculture modernization, human demography and complex topographic gradients of northwestern Argentina has resulted in processes of both forest recovery and deforestation, thus providing the opportunity to analyze patterns and driving forces of land-cover redistribution. We analyzed 20 years (1986-2006) of land-cover change in a subtropical watershed in relation to topographic and demographic variables. Although net forest change represented <1 %, forests redistribution affected 7 % of forest lands. There was a consistent geographic segregation of deforestation and forest recovery, with forests expanding over steep highlands and agriculture expanding over lowland irrigated areas. Population trends were not associated to forest expansion in lowlands but they explained 32 % of forest recovery in highlands. Highland forest expansion and lowland deforestation, respectively, imply conservation opportunities for humid montane forests and the environmental services they provide (e.g., watershed conservation) and threats for the conservation of dry forests and its biodiversity. Our study exemplifies the importance of land-use redistribution (rather than net change) with relevant environmental consequences at regional scale. [ABSTRACT FROM AUTHOR]

The Pampa in Argentina is a large plain with a quite obvious dependence on agriculture, water availability and its quality. It is a sensitive environment due to weather changes and slope variations. Supplementary irrigation is a useful practice for compensating the production in the zone. However, potential negative impacts of this type of irrigation in salinization and sodification of soils are evident. Most conventional methodologies for assessing water irrigation quality have difficulties in their application in the region because they do not adjust to the defined assumptions for them. Consequently, a new GIS-based methodology integrating multiparametric data was proposed for evaluating and delineating groundwater suitability zones for irrigation purposes in flat areas. Hydrogeological surveys including water level measurements, groundwater samples for chemical analysis and electrical conductivity (EC) measurements were performed. The combination of EC, sodium adsorption ratio, residual sodium carbonate, slopes and hydraulic gradient parameters generated an irrigation water index (IWI). With the integration of the IWI 1 to 3 classes (categories of suitable waters for irrigation) and the aquifer thickness the restricted irrigation water index (RIWI) was obtained. The IWI′s index application showed that 61.3 % of the area has 'Very high' to 'Moderate' potential for irrigation, while the 31.4 % of it has unsuitable waters. Approximately, 46 % of the tested area has high suitability for irrigation and moderate groundwater availability. This proposed methodology has advantages over traditional methods because it allows for better discrimination in homogeneous areas. [ABSTRACT FROM AUTHOR]

The article offers information on a symposium held in Mendoza, Argentina, in November 2007, on pre-harvest sprouting in cereals. Around 60 delegates from different countries attended the symposium, which was divided into five sessions including agronomic management, physiology of dormancy and germination etc. Keynote speakers were Daniel Miralles from the University of Buenos Aires, Argentina, Peter Chandler and Michael Foley among others.

A simple method of analysis was proposed to characterize the impact of climatic conditions of a wide region of Argentina (from 27°05′S to 35°48′S, from 61°5′W to 64°21′W) on potential maize ( Zea mays L.) grain yield, and the occurrence of various climatic constraints (low temperatures and low soil water content, frost, drought stress and heat stress) along the cycle. The analysis was based on previous studies of the eco-physiology of maize crops and the use of climatic records of six locations in the region under study. Results were analyzed using a probabilistic method, later organized as a checklist to consider when deciding on sowing date in a location of the region. Thus, for each production scenario (combination of location and sowing date), farmers would have a tool enabling them to pay particular attention to the restrictions more likely to occur, to include some cultural practices to avoid or mitigate the most severe climatic constraint to maize production. [ABSTRACT FROM AUTHOR]

A new form of populism, combining broad-based benefits for urban workers with export promotion, emerged in Argentina under Néstor Kirchner (2003–2007). This article argues that changes in agricultural production created the conditions for this “export-oriented populism.” Historically, Argentina’s main exports, beef and wheat, were also the primary consumption goods of urban workers. Scholars such as Guillermo O’Donnell have argued that this linkage increased rural-urban conflict, resulting in shifting coalitions and recurring crises. Today, soybeans have replaced beef and wheat as the country’s leading export. Because soybeans are not consumed by the working class, Kirchner could both promote and tax their export, generating fiscal revenue for populist programs while not harming the effective purchasing power of urban workers or provoking a balance-of-payments crisis. Export orientation thus provided the basis for a new variant of Argentine populism. This study offers a new argument within the classic research tradition on the interaction between politics and various types of export growth. It likewise provides an additional basis for arguing that populism, as a form of politics, can arise in diverse economic circumstances. Furthermore, this article contends that, rather than uniformly promoting political stability, the effect of export booms is conditioned by the nature of economic linkages between the export sector and the domestic economy. [ABSTRACT FROM AUTHOR]

We estimated carbon pools and emissions from deforestation in northern Argentine forests between 1900 and 2005, based on forest inventories, deforestation estimates from satellite images and historical data on forests and agriculture. Carbon fluxes were calculated using a book-keeping model. We ran 1000 simulations for a 105-year period with different combinations of values of carbon stocks (Mg C ha−1), soil carbon in the top 0.2 m, and annual deforestation series. The 1000 combinations of parameters were performed as a sensitivity analysis that for each run, randomly selected the values of each variable within a predefined range of values and probability distributions. Using the simulation outputs, we calculated the accumulated C emissions due to deforestation from 1900 to 2005 and the annual emission as the average of the 1000 simulations, and uncertainties of our estimates as the standard deviation. We found that northern Argentine forests contain an estimated 4.54 Pg C (2.312 Pg C in biomass and 2.233 Pg C in soil). Between 1900 and 2005 approximately 30% of the forests were deforested, yielding carbon emissions of 0.945 (SD = 0.270) Pg C. Estimated average annual carbon emissions between 1996 and 2005, mostly from deforestation of the Chaco dry forests, were 20,875 (SD = 6,156) Gg C y−1 (1 Gg = 10−6 Pg). These values represent the largest source of carbon from land-cover change in the extra-tropical southern hemisphere, between 0.9 and 2.7% of the global carbon emissions from deforestation, and approximately 10% of carbon emissions from the Brazilian Amazon. Deforestation, which has accelerated during the last decades as a result of modern agriculture expansion, represents a major national source of greenhouse gases and the second emission source, after fossil fuel consumption by fixed sources. We conclude that Argentine forests are an important carbon pool and emission source that need more attention for accurate global estimates, and seasonally dry forest deforestation is a key component of the Argentine carbon cycle. [ABSTRACT FROM AUTHOR]

The generation of reliable updated information is critical to support the harmonization of socio-economic and environmental issues in a context of sustainable development. The agro-environmental assessment and management of agricultural systems often relies on indicators that are necessary to make sound decisions. This work aims to provide an approach to (a) assess the environmental performance of commercial farms in the Pampas of Argentina, and (b) propose a methodological framework to calculate environmental indicators that can rapidly be applied to practical farming. 120 commercial farms scattered across the Pampas were analyzed in this study during 2002 and 2003. Eleven basic indicators were identified and calculation methods described. Such indicators were fossil energy (FE) use, FE use efficiency, nitrogen (N) balance, phosphorus (P) balance, N contamination risk, P contamination risk, pesticide contamination risk, soil erosion risk, habitat intervention, changes in soil carbon stock, and balance of greenhouse gases. A model named Agro-Eco-Index was developed on a Microsoft-Excel support to incorporate on-farm collected data and facilitate the calculation of indicators by users. Different procedures were applied to validate the model and present the results to the users. Regression models (based on linear and non-linear models) were used to validate the comparative performance of the study farms across the Pampas. An environmental dashboard was provided to represent in a graphical way the behavior of farms. The method provides a tool to discriminate environmentally friendly farms from those that do not pay enough attention to environmental issues. Our procedure might be useful for implementing an ecological certification system to reward a good environmental behavior in society (e.g., through tax benefits) and generate a commercial advantage (e.g., through the allocation of green labels) for committed farmers. [ABSTRACT FROM AUTHOR]

Agronomists, environmentalists, land managers, policy makers and development agents who make decisions at different levels (plot, farm, ecosystem, landscape, ecoregion, country) increasingly demand scientific information to understand cross-level links and interactions in systems that behave hierarchically. The purpose of this work is to study cross-scale relations and interactions in agricultural ecosystems of the Argentine Pampas. Based on public censuses and surveys from 1960 to 1996, data on crops cultivation, fossil energy (FE) consumption and energy productivity were used for the analysis. The whole region was divided into eight increasing geographic scales, and the impact of one scale on the broader ones was assessed through a simple analysis of energy productivity. Regression analysis was used to identify cross-scale linear slopes and to determine cross-scale interactions. We assume that non-parallel slopes in different years are attributable to cross-scale interactions. Given that the results show highly significant differences among inter-year slopes, we must accept that cross-scale interactions have occurred. Beyond any random behavior, it seems quite possible that decisions made at smaller scales may have a demonstrable effect on broader scales. Specific research is needed to elucidate key cause–effect relationships among scales. In principle, the possible interaction between intensification factors (for example, FE consumption) and spatial scales is a plausible hypothesis to be tested in the study area. [ABSTRACT FROM AUTHOR]

The wild tuber-bearing Solanum species represent a genetic pool of enormous diversity, embracing high variability for many agronomic traits. S. kurtzianum (ktz), S. chacoense (chc) and S. ruiz-lealii (rzl) are wild diploid self-incompatible relatives of the common potato, Solanum tuberosum ssp. tuberosum, with resistance to adverse biotic and abiotic factors. Pollen-pistil/style compatibility relations and seed set in intra- and interspecific crosses among ktz, chc and rzl were investigated. Pre- and post-zygotic hybridization barriers were detected in the three species, with variable incidence because the percentage of genotypic combinations that produced seeds was 15–30% and 7–28% in intra and interspecific crosses, respectively. In pollen-pistil/style incompatible combinations, either pollen grains did not germinate or pollen tube growth was arrested at different sites of the style, but mainly in its upper third. Unilateral incompatibility was detected in both intra- and interspecific crosses, as well as bilateral incompatibility in certain combinations. The incompatibility relations observed could be explained by a genetic model with dominant genes in pistils that interact with corresponding dominant genes in pollen, that are independent of the S-locus. The complex arrangement of compatibility relationships found could not be directly related to taxonomic hypothesis or geographic distribution. These results suggest that divergence between the three species has occurred recently, and that internal barriers of reproductive isolation have not been an important factor in their evolution. [ABSTRACT FROM AUTHOR]

Presents a study to evaluate the effects of grazing disturbance on insect communities at a montane grassland in Central Argentina. Comparison of two grazed sites differing in cattle load; Consideration of taxonomic and guild structure as important aspects of insect diversity; Measurement of abundance, richness, diversity and biomass of the insect assemblages; Findings that family taxonomic level could be as or even more appropriate than species level in order to characterize insect communities.

Focuses on functional and structural landscape indicators of intensification, resilience and resistance in agroecosystems in southern Argentina. Criteria to evaluate the environmental implications of intensive agricultural land use; Factors, which account for large fractions of the variance of the distribution of functional groups of the plant canopies; Features of the ecological theory on biodiversity, spatial organization and ecosystem stability.

Technological advancements and new production systems modify the conditions of natural environments. Transformations in an arid landscape caused by alfalfa cropping under pressurized irrigation systems have generated a conflict between farmers and Azara's tuco-tucos (Ctenomys azarae). Mounds produced by this species damage the alfalfa cutting equipment, reduce the lifespan of harvesting machinery, and results in high production costs. The goal of this study was to determine the production variables that influence density and spatial distribution pattern of Azara's tuco-tucos' mounds within the alfalfa plots under center-pivot irrigation. We assessed the frequency and distribution of Azara's tuco-tuco mounds in plots under center-pivot irrigation during two alfalfa crop seasons. Using generalized linear models, we determined that the total number of mounds and the number of active mounds were positively related to alfalfa's stand age and height. However, there are likely other variables that we did not include that should be considered to reduce the number of mounds and, therefore, mitigate damage. Considering the emerging implementation of new agricultural practices and the distribution area of the genus Ctenomys, this unprecedented work in Latin America contributes necessary and important information for better pest control management. [ABSTRACT FROM AUTHOR]

This work presents the results of a soil erosion study using the 7Be technique. This technique estimates the water erosion/deposition from the comparison between 7Be soil content of a reference site and an eroded or sedimented site. The soil samples were collected from an agricultural area of the semiarid region of Argentina near San Luis City, which has a marked rainfall season. The area has been used for crop cultivation, being subjected to plowing practices. The 7Be in the Reference Site was in the first centimeter of soil, showing the typical exponential decreasing of 7Be soil content with depth, with the 7Be inventories value being 340 ± 50 Bq m−2 for the dry season and 571 ± 48 Bq m−2 for the rainy season. The 7Be technique was applied to a potential eroded site subjected to traditional tillage practices (plowing). A net soil erosion value of 13.5 t ha−1 (1.35 kg m−2) was obtained. From the assumptions of the applied technique, we can draw the inference that this erosion was caused by rains produced in the month prior to the date of soil sampling. [ABSTRACT FROM AUTHOR]