Degradación química en Acrisoles bajo diferentes usos y pendientes en la sabana de Huimanguillo, Tabasco, México

Objective: To evaluate the chemical soil degradation caused by nutrients lost in Acrisols from the Savannah of Huimanguillo, Tabasco, Mexico. Design/methodology/approach: The effect of two factors, land use and slope relief, were study. Properties evaluated were soil organic matter (SOM), total nitrogen (Nt), available phosphorus (P), Cation Exchange Capacity (CEC), and exchangeable cations (K, Ca, Mg, Na). Results: The content of SOM were considerate rich to very rich, and did not showed any significant differences between factors. Nt was statistically high, and K was statistically low. P, CEC, Ca, Mg and Na showed statistically differences and lower contents. Limitations of study/implications: Soil degradation is a global problem, therefore the necessity of studies to understand the effect of land use over soil fertility and land chemical conditions. Findings/conclusions: The results indicates presence of chemical degradation in Acrisols, mostly by effect of land use and suggest the necessity of conservation strategies.Objetivo: Evaluar la degradación química del suelo por pérdida de nutrientes en Acrisoles de la Sabana de Huimanguillo, Tabasco, México. Diseño/Metodología/Aproximación: Se estudió el efecto de dos factores, los usos del suelo y las pendientes del relieve. Las propiedades evaluadas fueron materia orgánica del suelo (MOS), nitrógeno total (Nt), fosforo extraíble (P), Capacidad de Intercambio Catiónico (CIC), y bases intercambiables (K, Ca, Mg, Na). Resultados: Los contenidos de MOS son considerados de ricos a muy ricos, sin diferencias significativas entre factores. El Nt fue alto y el K intercambiable bajo, mostrando diferencias significativas. El P, CIC, Ca, Mg y Na mostraron diferencias significativas y contenidos bajos. Limitaciones del estudio/implicaciones: La degradación del suelo constituye un problema global, es necesario estudiar el efecto que tiene el uso del suelo sobre la fertilidad y condiciones químicas de la tierra. Hallazgos/conclusiones: Los resultados muestran la existencia de degradación química en Acrisoles del área de estudio principalmente por efecto del uso del suelo, sugiriendo la necesidad de estrategias de conservación

Atlantic Leatherback Migratory Paths and Temporary Residence Areas

BACKGROUND: Sea turtles are long-distance migrants with considerable behavioural plasticity in terms of migratory patterns, habitat use and foraging sites within and among populations. However, for the most widely migrating turtle, the leatherback turtle Dermochelys coriacea, studies combining data from individuals of different populations are uncommon. Such studies are however critical to better understand intra- and inter-population variability and take it into account in the implementation of conservation strategies of this critically endangered species. Here, we investigated the movements and diving behaviour of 16 Atlantic leatherback turtles from three different nesting sites and one foraging site during their post-breeding migration to assess the potential determinants of intra- and inter-population variability in migratory patterns. METHODOLOGY/PRINCIPAL FINDINGS: Using satellite-derived behavioural and oceanographic data, we show that turtles used Temporary Residence Areas (TRAs) distributed all around the Atlantic Ocean: 9 in the neritic domain and 13 in the oceanic domain. These TRAs did not share a common oceanographic determinant but on the contrary were associated with mesoscale surface oceanographic features of different types (i.e., altimetric features and/or surface chlorophyll a concentration). Conversely, turtles exhibited relatively similar horizontal and vertical behaviours when in TRAs (i.e., slow swimming velocity/sinuous path/shallow dives) suggesting foraging activity in these productive regions. Migratory paths and TRAs distribution showed interesting similarities with the trajectories of passive satellite-tracked drifters, suggesting that the general dispersion pattern of adults from the nesting sites may reflect the extent of passive dispersion initially experienced by hatchlings. CONCLUSIONS/SIGNIFICANCE: Intra- and inter-population behavioural variability may therefore be linked with initial hatchling drift scenarios and be highly influenced by environmental conditions. This high degree of behavioural plasticity in Atlantic leatherback turtles makes species-targeted conservation strategies challenging and stresses the need for a larger dataset (>100 individuals) for providing general recommendations in terms of conservation

The clinical relevance of oliguria in the critically ill patient : Analysis of a large observational database

Funding Information: Marc Leone reports receiving consulting fees from Amomed and Aguettant; lecture fees from MSD, Pfizer, Octapharma, 3 M, Aspen, Orion; travel support from LFB; and grant support from PHRC IR and his institution. JLV is the Editor-in-Chief of Critical Care. The other authors declare that they have no relevant financial interests. Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Urine output is widely used as one of the criteria for the diagnosis and staging of acute renal failure, but few studies have specifically assessed the role of oliguria as a marker of acute renal failure or outcomes in general intensive care unit (ICU) patients. Using a large multinational database, we therefore evaluated the occurrence of oliguria (defined as a urine output 16 years) patients in the ICON audit who had a urine output measurement on the day of admission were included. To investigate the association between oliguria and mortality, we used a multilevel analysis. Results: Of the 8292 patients included, 2050 (24.7%) were oliguric during the first 24 h of admission. Patients with oliguria on admission who had at least one additional 24-h urine output recorded during their ICU stay (n = 1349) were divided into three groups: transient - oliguria resolved within 48 h after the admission day (n = 390 [28.9%]), prolonged - oliguria resolved > 48 h after the admission day (n = 141 [10.5%]), and permanent - oliguria persisting for the whole ICU stay or again present at the end of the ICU stay (n = 818 [60.6%]). ICU and hospital mortality rates were higher in patients with oliguria than in those without, except for patients with transient oliguria who had significantly lower mortality rates than non-oliguric patients. In multilevel analysis, the need for RRT was associated with a significantly higher risk of death (OR = 1.51 [95% CI 1.19-1.91], p = 0.001), but the presence of oliguria on admission was not (OR = 1.14 [95% CI 0.97-1.34], p = 0.103). Conclusions: Oliguria is common in ICU patients and may have a relatively benign nature if only transient. The duration of oliguria and need for RRT are associated with worse outcome.publishersversionPeer reviewe

In Situ Measurements of Circulation Features Influencing Cross-Shelf Transport Around Northwest Cuba

We analyzed circulation processes sampled in the Gulf of Mexico in May 2016 by the National Oceanic and Atmospheric Administration (NOAA) Ship Nancy Foster. This data set is one of the first in situ surveys in Cuban waters available to the international community. Along northwest Cuba, these data suggested coastal upwelling and revealed, for the first time, a ~50 km diameter Cuban ANticyclonic (CubAN) eddy and a ~25 km diameter cyclonic eddy, which together advected upwelled waters offshore. The CubAN eddy was associated with downwelling, and the cyclonic eddy with upwelling. At the western tip of Cuba, local currents were predominantly anticyclonic, presumably due to the proximity of the retracted Loop Current, with limited export of coastal waters. Conversely, additional data from two cruises when the Loop Current was extended showed cyclonic circulation within upwelling filaments extending far offshore. These processes are important, as they can potentially entrain marine organism larvae from local reefs into the Loop Current system and to other reef ecosystems of the region. They might also affect the transport of pollutants, as hydrocarbons in case of a spill in Cuban waters. The 2016 cruise took place after the shedding of a Loop Current Ring, which involved an unusually large (~250 km) cyclonic frontal eddy. The eddy signature was observed down to 1,200 m depth, deeper than the Loop Current. A surface drifter revealed a low relative vorticity (0.19 f) inside the eddy. Along its southern edge, filaments exported from the Campeche Bank were associated with high relative chlorophyll a at 3,060 m depth

Economic evaluation of climate risk adaptation strategies: Cost-benefit analysis of flood protection in Tabasco, Mexico

Economic losses as a result of natural hazards have been rising over the past few decades due to socio-economic development and perhaps climate change. This upwards trend is projected to continue, highlighting the need for adequate adaptation strategies. This raises the question of how to determine which adaptation strategies are preferred to cope with uncertain climate change impacts. This study shows how a multi-disciplinary cascade of hazard modelling, risk modelling, and a cost-benefit analysis can be applied to provide a first indicator of economically efficient adaptation strategies. We apply this approach to an analysis of flood risk and the desirability of flood protection in the state of Tabasco in Mexico, which faces severe flooding on an almost yearly basis. The results show that expected annual damage caused by coastal flooding is expected to increase from 0.53 billion USD today up to 4.12 billion USD in 2080 due to socio-economic development and climate change. For river floods, expected annual damages are estimated to increase from 1.79 billion USD up to 10.6 billion USD in 2080 if no adaptation measures are taken. Based on the estimated risk and cost-benefit analysis of installing flood protection infrastructure, we determined the economically optimal protection standards for both river and coastal floods as at least 100 years, if we take into account climate change. Our main conclusions are robust to key uncertainties about climate change impacts on flood risks, indirect damage caused by floods, the width of the protected floodplains, and the adopted social discount rate. We discuss how our multi-disciplinary approach can assist policy-makers in decisions about flood risk management, and how future research can extend our method to more refined local analyses which are needed to guide local adaptation planning

Unidades oceanográficas del Golfo de México y áreas adyacentes: La integración mensual de las características biofísicas superficiales

El Golfo de México (GoM) es una región oceánica de una dinámica y complejidad particular, que se evidencia en las variaciones espacio temporales de la configuración de sus aguas superficiales. Varios estudios han utilizado las características superficiales térmicas, biológicas o de circulación para proponer subdivisiones estáticas del GoM; sin embargo, ninguna investigación ha regionalizado la zona integrando distintos aspectos oceanográficos de forma dinámica. El objetivo de este trabajo fue proponer una división del GoM que considerara las características físicas y biológicas y que permitiera analizar la evolución mensual espacial de las unidades en un año promedio. Utilizamos análisis multivariados para reconocer la estructura subyacente de los datos, para generar una expresión espacial mensual de los conglomerados y para probar la robustez de los resultados. Se obtuvieron 18 regiones denominadas unidades oceanográficas (UO) que condensan diversas características superficiales del GoM. Se observaron dos grupos de UO: aquellas que están relacionadas con las propiedades de circulación y aquellas que fueron definidas por la asociación de las características biológicas y térmicas. Quince UO están presentes a lo largo del año, mientras que dos tienen presencia únicamente en verano. Todas las UO tienen variaciones temporales tanto en sus características biofísicas como en su expresión espacial. Este estudio propone una manera novedosa de particionar un sistema marino y aporta parámetros cuantitativos interpretables de las UO propuestas. La representación de la variabilidad de unidades oceanográficas homogéneas provee información valiosa para el manejo diferenciado de recursos marinos asociados temporalmente a masas de agua especificas. Los resultados obtenidos proveen también bases robustas para analizar de manera condensada la dinámica de largo plazo de un sistema tan complejo como es el GoM. doi: https://doi.org/10.22201/igeof.00167169p.2019.58.4.205