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Habitat loss due to land-use change is the greatest threat to biodiversity on a global scale, and agriculture has been the principal driver of change. In Uruguay, the conversion of native grasslands to croplands (e.g., soybean) and exotic forest plantations (Eucalyptus and Pinus) has accelerated during the last two decades. We studied the vulnerability of vertebrate and woody plant diversity to the loss of grassland areas, driven by agricultural and forestry expansion, to identify priority areas for conservation. We assessed the spatial variability of biodiversity vulnerability in function of species richness and number of focal species (i.e., prioritized species) of woody plants and terrestrial vertebrates that use grassland ecosystem as habitat. The top 17% of vulnerable sites (51 of 302 cells) were selected as priority conservation areas for Uruguay, following Aichi Target number 11. Approximately 36 % of the original continental territory of Uruguay, mainly grasslands, was converted to cropland (28%) and exotic forest plantations (8%) in 2015. Approximately 27% of the priority cells for conservation of vertebrates and woody plant diversity have been transformed, especially in three ecoregions in which habitat loss was between 35-45%. We simulated a land-use scenario for 2030, based on national production goals of soybean and exotic forest plantations, projecting that: (1) the overall loss of original habitat (mainly grasslands) would reach 48% of the country's land area, and (2) 45% of the priority cells would be converted to agricultural lands, especially in four ecoregions, with habitat losses greater than 50%. Our results suggest an urgent need to develop strategies to reduce the rate of natural grassland loss in Uruguay, as well as to conserve biodiversity and ecosystem services associated with these systems. Conservation efforts should focus on prioritized cells, especially those with no protection status and a high likelihood of agricultural conversion in 2030, through expanding public and private protected areas and promoting wildlife-friendly agricultural alternatives, such as beef production in natural grasslands. [ABSTRACT FROM AUTHOR]

Droughts significantly impact livestock systems over natural grasslands. Nevertheless, the practices adopted by cattle producers are usually not adaptive, and therefore they deepen the impacts of the drought and its vulnerability. Drought vulnerability assessments have implicitly considered vulnerability as an individual phenomenon and have not considered the interactions of actors and agents as a key attribute. Social network analysis (SNA) can be used to analyse these processes. However, researchers have largely used SNA from a static perspective and failed to not consider that external drivers could modify the network. The objective of this work was to analyse the incidence of interactions between cattle producers, institutions and agricultural technicians and the effect of such interactions on drought vulnerability from a dynamic perspective. We worked with two operational frameworks, SNA and the incidence of external drivers on the network. Our primary results highlight that (1) cattle producers of greater centrality present lower vulnerability; (2) central cattle producers are not necessarily identified by other producers by the management they carry out; (3) the primary external driver partially affects the structure of the network; and (4) the existence of rigidity and poverty traps and difficulties hindering the propagation and consolidation of practices that reduce drought vulnerability became evident. Our findings enable the identification of potentialities and barriers in the transfer of information to increase adaptation and reduce vulnerability to drought and provide a framework that could be applicable to other productive sectors, threats and geographical contexts. [ABSTRACT FROM AUTHOR]

Five catchment areas in Uruguay were selected to conduct a nutrient exportation analysis and to evaluate the effects of current land use on the eutrophication of coastal lagoons. Satellite images and national agriculture censuses were used for a quantitative analysis of land use changes from 1974 to 2005, and a nutrient export coefficient approximation was used to determine long-term changes in annual loads. Several eutrophication indicators (water, sediment and autotrophic communities) were assessed seasonally in the lagoon basins during 2005 and 2006. The areal annual load of nutrients exported to the lagoons increased over time. Population and extensive livestock ranching were the most important nutrient sources, while agriculture is increasing in importance. Buffer effects of riparian forests on eutrophication indicators were observed in contrast to the wetlands surrounding the lagoons, which seem to be acting as a source of nutrients. Catchment size was inversely related to most eutrophication indicators. Afforestation and agriculture were found not to directly impact eutrophication indicators, however, catchments with larger agricultural areas showed higher concentrations of suspended solids, which may indicate the export of particulate nutrients. Salinity was inversely related to most eutrophication indicators, suggesting that the manipulation of the sand bar of the lagoons is a critical management issue. Sediment-related eutrophication indicators were more sensitive to changes in land uses and covers, in contrast with the more variable water column indicators, suggesting their potential use as enduring indicators. This research provides a rapid and integral assessment for qualitatively linking catchment changes with eutrophication indicators in coastal environments, which can easily be replicated to track pollutants in locations that lack standardized monitoring programs needed for more complex catchment modeling approaches. [ABSTRACT FROM AUTHOR]

Roads are one of the main causes of loss of biodiversity, with roadkill one of the main causes of mortality. The aim of this research was to identify sites with a high probability of roadkill of medium and large mammals, and the environmental variables that would explain it. We used the favourability function (F) to build the predictive models. There were 57 explanatory variables, and we collected 685 records of 10 species of medium and large native wild mammals from the ECOBIO Uruguay databases. They were grouped into native forest and grassland species, according to the main habitat. Two models were developed, one with all the variables and one with the anthropogenic variables. For both groups, the model obtained with all the variables was the most significant according to the evaluation indices used. This made it possible to identify the hot spots of roadkill (F > 0.6) for each of the groups. The anthropic variables were the ones that best explained these hot spots. This allowed the identification of sites where the probability of roadkill is high and requires a monitoring plan to implement mitigation measures in the future. [ABSTRACT FROM AUTHOR]

The environment is a central axis of academic discussion, but even so, there are theoretical difficulties in understanding environmental problems. Environmental Geography provides arguments to articulate the relationships between society and nature and the possibility of focusing on the environmental system as an object of study. The aim of this article is to provide theoretical, methodological and operational elements for the evaluation of the interrelationship between wetland ecosystems and urban localities in Uruguay based on three case studies and analysing them from the theoretical and conceptual context of Environmental Geography. The methodological strategy is based on a multi‐scale analysis: at the national scale, studying the situation of the interrelationship between wetlands and urban areas, and at the basin scale, case studies are selected to address the specific conditions of the relationship. In Uruguay, 50% of urban localities are located in wetland territories, but no national strategy can be identified to solve the problem of flooding events in urban areas. Environmental Geography offers the possibility of making the interrelationships between urban spaces and the environments where they develop visible as it makes it possible to analyse the causes of the problem at the basin level in order to achieve sustainable management. [ABSTRACT FROM AUTHOR]

Livestock system structure is a relevant factor in determining the decision-making processes and the initiatives to reduce the vulnerability to external drivers. The definition of livestock stocking density (LSD) is a key factor as it determines the sustainability of the activity. LSD adjusted to grassland productivity in space, and time has been advocated by researchers and policy makers. However, most livestock farmers fail to adjust the LSD, and therefore, their vulnerability increases. This study explored the hypothesis that productive decisions in livestock systems include information that reinforced the vulnerability. The main objective of this study was to evaluate vulnerability of livestock farmers through the information that guides the decision-making process. We analyze information based on which farmers define the LSD, focusing on the relationship between the farmers' perception of grassland productivity, the main reasons for their decisions, and grassland productivity using remote sensing techniques. The research strategy integrated interviews with farmers regarding LSD and grassland aboveground net primary productivity estimates. The results showed that 77% of the farmers use LSD higher than the carrying capacity, although 66% of them do so knowingly. Consequently, most farmers are in a situation of high vulnerability, especially to rainfall regime variability. Almost all farmers are affected by at least one trap: poverty, rigidity, or gilded. A clear contradiction is identified between the farmer's decisions and the current recommendations suggested by researchers and public policy, which are mainly explained by the farmers' optimism. Results highlight the access to information as a great barrier to the adoption of adaptive strategies. We show for the first time the main traps and its causal associated mechanisms, which limit the decision-making of Uruguayan livestock farmers. The proposed framework can be used in other agricultural systems to identify barriers and traps, as the first step toward increasing agroecosystem sustainability. [ABSTRACT FROM AUTHOR]

In recent decades, the Río de la Plata Estuary has shown an increase in the frequency and intensity of phytoplankton blooms with negative impacts on production activities, human health, and biodiversity. Water quality monitoring programs provide samples from the coastal zone alone, which limits the collection of data inside the Estuary and the analysis of the spatio-temporal dynamics of phytoplankton blooms, as well as their relationship with flow rate. In this work, a systematic satellite monitoring of the Estuary was carried out for the first time. Sentinel-2 images captured during 2016–2021 were used along with the Normalized Difference Chlorophyll Index. It included one year of El Niño, one neutral year and two consecutive years of La Niña. Four zones with the highest frequency of bloom occurrence were delimited. Data on the extent and intensity in which blooms occurred were extracted and related to the flow rates of the main tributaries using Bayesian models. The most intense and frequent blooms were detected on the southern and northern coasts, respectively (maximum values of 515 km2 in January 2021, NDCI>0.06), followed by a wide area of intense phytoplankton development inside the Estuary. Blooms were more frequent in warmer months, with elevated Chl- a concentrations in 75% of the months of the study period on the Argentine coast, and 50% on the Uruguayan coast. Blooms were positively correlated with low flows. Therefore, the most extensive and intense bloom episodes occur during La Niña events. During El Niño, the high flows transport the biomass originating in the Estuary and in the hydroelectric reservoirs located upstream, which can even be transported along the northern coast. This work identified a recurrent pattern of phytoplankton blooms and the hydro-meteorological conditions that favor their magnification in a context of strong climate variability in the region and estuarine eutrophication. [Display omitted] • Eutrophication in the Río de la Plata estuary (RdlP) show signs of worsening. • Analysis of Sentinel-2 images revealed extensive phytoplankton blooms from 2016 to 2021. • Four zones of high frequency phytoplankton bloom occurrence were delimited. • Bayesian modeling show greatest blooms under La Niña and high transport in El Niño. • Recurring pattern of blooms was identified in RdlP under extreme climate variability. [ABSTRACT FROM AUTHOR]

Agricultural intensification promotes floods and threatens family livestock production in the protected area of Farrapos Estuaries, Uruguay. Using the Holistic Risk Index (Barrera, J. F., Herrera, J., and J. Gómez.Riesgo-vulnerabilidad hacia la broca del café bajo un enfoque de manejo holístico.La Broca del Café en América Tropical: Hallazgos y Enfoques. ECOSUR-SME 2007), this study analyzes the interrelationships among threat, vulnerability and responsiveness. Four livestock producers were shown to have low risk due to their high responsiveness; eighteen producers were shown to have medium risk and were divided into high vulnerability, low vulnerability and increased responsiveness groups; and three producers were shown to have high risk due to high threat and vulnerability and a lower responsiveness. Responsiveness is related to the use of agroecological principles and the agroecological criteria that guide strategies among producers and within the protected area. [ABSTRACT FROM AUTHOR]

Glyphosate is one of the most used herbicides worldwide. However there still exists a strong debate about its effects on the environment or people health. In this context, the metric analysis is a methodology increasingly used to quantify and evaluate the scope of the scientific production around a specific topic. The goal of this work was to characterize the context of knowledge generation about glyphosate. All the scientific production linked to glyphosate was analyzed in the period from 1974 to 2016, using the Web of Science (WOS) as a source of information and "glyphosate" as a search criterion. A total of 8174 records were found. The bibliographic production on this herbicide experienced a sustained increase. There was a concentration in knowledge generation led by the United States. Monsanto Company produced the largest number of articles during the first thirty years of the development of this topic. Research around glyphosate in South America gained importance as of the year 2000, with Brazil being the country with the highest production followed by Argentina. A large proportion of research was focused on agricultural science, while the analysis of toxicology or environmental effects did not begin until the year 2000, and it is still insufficient. Unlabelled Image • Production on glyphosate shows exponential growth since its inception in 1974. • The United States leads production, reaching 46% in the most productive period. • Monsanto led production until the year 2000. • Brazil and Argentina will lead production in Latin America from 2001. • Toxicity studies linked to glyphosate have just started as of 2011. [ABSTRACT FROM AUTHOR]

Heat-killed (HK) Mycobacterium obuense is a novel immunomodulator, currently undergoing clinical evaluation as an immunotherapeutic agent in the treatment of cancer. Here, we examined the effect of in vitro exposure to HK M. obuense on the expression of different categories of surface receptors on human blood myeloid (m) and plasmacytoid (p) DCs. Moreover, we have characterized the cytokine and chemokine secretion patterns of purified total blood DCs stimulated with HK M. obuense. HK M. obuense significantly up-regulated the expression of CD11c, CD80, CD83, CD86, CD274 and MHC class II in whole-blood mDCs and CD80, CD123 and MHC class II in whole-blood pDCs. Down-regulation of CD195 expression in both DC subpopulations was also noted. Further analysis showed that HK M. obuense up-regulated the expression of CD80, CD83 and MHC class II on purified blood DC subpopulations. TLR2 and TLR1 were also identified to be engaged in mediating the HK M. obuense-induced up-regulation of surface receptor expression on whole blood mDCs. In addition, our data demonstrated that HK M. obuense augmented the secretion of CCL4, CCL5, CCL22, CXCL8, IL-6, IL-12p40 and TNF-a by purified total blood DCs. Taken together, our data suggest that HK M. obuense exerts potent differential immunomodulatory effects on human DC subpopulations. [ABSTRACT FROM AUTHOR]

This article presents a highly detailed territorial assessment for aquaculture production in Uruguay and a methodology to identify the most suitable areas in order to develop the activity. Furthermore, it proposes the basis to generate a dynamic modelling tool of high spatial resolution to support the decision-making process regarding national aquaculture activities. The modelling structure of aquaculture suitability was developed by the construction of a hierarchical model, combining a multicriteria assessment and a geographic information system. Forty-one attributes were integrated in six aptitude models: one model for each one of the five common production systems intended to be the most viable in Uruguay and a sixth aptitude indicator that summarizes those five systems, representing the maximum suitability for aquaculture activities. In addition, the hierarchical model allows measurement and identification of relative weights of each model, according to the planning scale, ranging from basin to cell. [ABSTRACT FROM AUTHOR]

Macrophages (Mφs) are instrumental regulators of the immune response whereby they acquire diverse functional phenotypes following their exposure to microenvironmental cues that govern their differentiation from monocytes and their activation. The complexity and diversity of the mycobacterial cell wall have empowered mycobacteria with potent immunomodulatory capacities. A heat-killed (HK) whole-cell preparation of Mycobacterium obuense (M. obuense) has shown promise as an adjunctive immunotherapeutic agent for the treatment of cancer. Moreover, HK M. obuense has been shown to trigger the differentiation of human monocytes into a monocyte-derived macrophage (MDM) type named Mob-MDM. However, the transcriptomic profile and functional properties of Mob-MDMs remain undefined during an activation state. Here, we characterized cytokine/chemokine release patterns and transcriptomic profiles of lipopolysaccharide (LPS)/interferon γ (IFNγ)-activated human MDMs that were differentiated with HK M. obuense (Mob-MDM(LPS/IFNγ)), macrophage colony-stimulating factor M-MDM(LPS/IFNγ)), or granulocyte/macrophage colony-stimulating factor (GM-MDM(LPS/IFNγ)). Mob-MDM(LPS/IFNγ) demonstrated a unique cytokine/chemokine release pattern (interleukin (IL)-10low, IL-12/23p40low, IL-23p19/p40low, chemokine (C-x-C) motif ligand (CXCL)9low) that was distinct from those of M-MDM(LPS/IFNγ) and GM-MDM(LPS/IFNγ). Furthermore, M-MDM(LPS/IFNγ) maintained IL-10 production at significantly higher levels compared to GM-MDM(LPS/IFNγ) and Mob-MDM(LPS/IFNγ) despite being activated with M1-Mφ-activating stimuli. Comparative RNA sequencing analysis pointed to a distinct transcriptome profile for Mob-MDM(LPS/IFNγ) relative to both M-MDM(LPS/IFNγ) and GM-MDM(LPS/IFNγ) that comprised 417 transcripts. Functional gene-set enrichment analysis revealed significant overrepresentation of signaling pathways and biological processes that were uniquely related to Mob-MDM(LPS/IFNγ). Our findings lay a foundation for the potential integration of HK M. obuense in specific cell-based immunotherapeutic modalities such as adoptive transfer of Mφs (Mob-MDM(LPS/IFNγ)) for cancer treatment. [ABSTRACT FROM AUTHOR]

The Río de la Plata estuary drains the second largest river basin of South America. The occurrence of frequent cyanobacterial blooms of the Microcystis and Dolichospermum complex in the Uruguayan coast are associated with high flows of Uruguay River due to rainy years. In summer 2019, a massive cyanobacterial bloom reached up to the Uruguayan Atlantic coast. This study seeks to unveil the origin and the environmental conditions that favored the occurrence of the last cyanobacterial bloom in the Río de la Plata, and to contribute with the development of an early warning system of cyanobacterial scum on Montevideo beaches. A complementary approach was applied with Sentinel-2 imagery, environmental data of monitoring programs of Salto Grande Reservoir and Montevideo beaches, hydro-meteorological information, and hydroelectric dam operation. Images were analyzed with the Normalized Difference Chlorophyll Index (NDCI), which allowed evaluating several water bodies within the same ranges. Positive anomalous rainfall increased river flows, particularly that of Uruguay and Negro rivers, which caused the opening of the dam spillways. NDCI maps showed that areas with high values (NDCI >0.06) in Salto Grande reservoir kept a similar surface area before and after the prolonged overflow period (8.7–7.8 km2, before and after). In the Río Negro reservoirs, however, NDCI >0.06 coverage remarkably changed (62.5 km2, Palmar reservoir), with a subsequent 56-fold reduction in the post-discharge of surface water. Twenty days after opening the spillways, Montevideo beaches were closed to swimming and the NDCI >0.06 surface reached 51.7 km2 in the Río de la Plata coast. The dynamics of NDCI areas, the downstream bloom discharge, and the predicted Río de la Plata residual currents, suggest that the cyanobacterial bloom originated in the Negro River (Palmar reservoir). This bloom event was one of the worst that occurred in the Río de la Plata in last 20 years, circulated along the Uruguayan sub-corridor to the Atlantic coast along 690 km from its origin, and lasted three months on Montevideo coast. This is the first study that addresses the impact of cyanobacterial blooms from the Negro River reservoirs on the Río de la Plata estuary. Therefore, the Negro River basin is where the main efforts should be directed to mitigate massive cyanobacterial blooms. Image 1 • The greatest cyanobacterial bloom of the decade was evaluated in the Río de la Plata. • Sentinel-2 NDCI-chlorophyll and hydrology revealed the bloom origin and displacement. • The Palmar reservoir of Negro River originated and discharged the bloom downstream. • High Uruguay River flow displaced the bloom along Río de la Plata coast to the Ocean. • A framework of a four level early warning system based in on-line data is proposed. [ABSTRACT FROM AUTHOR]