Ojos que no ven… ¿Qué podemos hacer para incluir más a la fracción subterránea en estudios de vegetación?

Conocer la estructura y el funcionamiento de la fracción subterránea de la vegetación es fundamental para comprender numerosos procesos que ocurren en distintos niveles de organización. Sin embargo, dicha fracción fue menos estudiada que su contraparte aérea, principalmente por el gran esfuerzo que demanda muestrearla a campo y procesarla en el laboratorio. En la XXVIII Reunión Argentina de Ecología (Mar del Plata, 2018) se realizaron dos simposios sobre la importancia de conocer las raíces en estudios ecológicos. De los simposios surgió la necesidad de 1) cuantificar los estudios que hayan evaluado las fracciones subterránea y aérea de la vegetación, y 2) determinar las metodologías empleadas y las variables de la fracción subterránea registradas en sistemas naturales (i.e., pastizales, estepas, bosques, arbustales y desierto) y antropizados (i.e., pasturas y cultivos) en seis provincias fitogeográficas de la Argentina y en dos regiones geomorfológicas de Uruguay. Se registraron 933 estudios publicados entre 1990 y 2019. El 57% y el 23% correspondieron a estudios exclusivos de la fracción aérea y de la subterránea, respectivamente, con un incremento exponencial en el tiempo de ambas fracciones. En la actualidad existe una tendencia a incorporar el compartimiento subterráneo en estudios ecológicos. Mediante un análisis sistemático se encontró que se emplearon seis métodos de muestreo (barreno, ruleros, planta entera, monolitos, rhizotron y estimación de la biomasa subterránea a partir de la biomasa aérea) para evaluar cuatro variables (biomasa subterránea, productividad primaria neta subterránea, algunos atributos radicales y tasa de descomposición radical). El método más empleado fue el del barreno y la variable más evaluada fue la biomasa subterránea. Proponemos fomentar la colaboración entre equipos de investigación y establecer comparaciones metodológicas para comprender los alcances de los resultados y obtener estimaciones más confiables sobre las consecuencias del cambio en el uso del suelo.To know the structure and functioning of the belowground vegetation compartment is essential to understand numerous processes that occur at different organization levels. However, the belowground vegetation compartment has traditionally been less studied than the above layer due to the great effort required for field sampling and laboratory processing. In the XXVIII Reunión Argentina de Ecología, Mar del Plata 2018, two symposia about the importance of root knowledge in ecological studies were conducted. From this exchange arose the need to 1) quantify studies that include data of belowground and aboveground vegetation, and 2) determine the methodologies and the variables of the belowground compartment recorded in natural (grasslands, steppes, forests, shrubs, and desert) and human modified systems (pastures, crops) in six Argentinean phytogeographic provinces and in two Uruguayan geomorphological regions. There were 933 published studies from 1990 to 2019. The 57% and 23% corresponded to exclusive studies of the above and belowground compartments respectively, with an exponential increase in the time of both fractions. Currently, there is a tendency to incorporate the underground compartment in ecological studies. Through systematic analysis, it was found that six sampling methods were used (soil core, ingrowth cores, trench, monoliths, rhizotron and belowground biomass estimation from aboveground biomass) where four variables of the belowground vegetation compartment were recorded (belowground biomass, belowground net primary productivity, root traits, and roots decomposition rate). Obtaining soil volumes by soil core was the most used method, while belowground biomass was the most evaluated variable. We propose to encourage collaboration between research teams and establish methodological comparisons to understand the scope of the results and obtain better estimates about the consequences of land-use change.EEA Santa CruzFil: López Mársico, Luis. Universidad de la República. Facultad de Ciencias. Instituto de Ecología y Ciencias Ambientales; UruguayFil: Pestoni, Sofía. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Conti, Georgina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Pérez-Harguindeguy, Natalia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Pinto, Priscila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Sarquis, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Reyes, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad Nacional del Comahue. Facultad de Ambiente y Salud. Laboratorio de Rehabilitación y Restauración de Ecosistemas Áridos y Semiáridos (LARREA); ArgentinaFil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Universidad Nacional de la Patagonia Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Piñeiro, Gervasio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de la República. Facultad de Agronomía. Departamento de Sistemas Ambientales; Urugua

The improbable transmission of Trypanosoma cruzi to human: the missing link in the dynamics and control of Chagas disease

Chagas disease has a major impact on human health in Latin America and is becoming of global concern due to international migrations. Trypanosoma cruzi, the etiological agent of the disease, is one of the rare human parasites transmitted by the feces of its vector, as it is unable to reach the salivary gland of the insect. This stercorarian transmission is notoriously poorly understood, despite its crucial role in the ecology and evolution of the pathogen and the disease. The objective of this study was to quantify the probability of T. cruzi vectorial transmission to humans, and to use such an estimate to predict human prevalence from entomological data. We developed several models of T. cruzi transmission to estimate the probability of transmission from vector to host. Using datasets from the literature, we estimated the probability of transmission per contact with an infected triatomine to be 5.8x10(-4) (95%CI: [2.6; 11.0] x 10(-4)). This estimate was consistent across triatomine species, robust to variations in other parameters, and corresponded to 900-4,000 contacts per case. Our models subsequently allowed predicting human prevalence from vector abundance and infection rate in 7/10 independent datasets covering various triatomine species and epidemiological situations. This low probability of T. cruzi transmission reflected well the complex and unlikely mechanism of transmission via insect feces, and allowed predicting human prevalence from basic entomological data. Although a proof of principle study would now be valuable to validate our models' predictive ability in an even broader range of entomological and ecological settings, our quantitative estimate could allow switching the evaluation of disease risk and vector control program from purely entomological indexes to parasitological measures, as commonly done for other major vector borne diseases. This might lead to different quantitative perspectives as these indexes are well known not to be proportional one to another

Daily allergic multimorbidity in rhinitis using mobile technology:a novel concept of the MASK study

Background: Multimorbidity in allergic airway diseases is well known, but no data exist about the daily dynamics of symptoms and their impact on work. To better understand this, we aimed to assess the presence and control of daily allergic multimorbidity (asthma, conjunctivitis, rhinitis) and its impact on work productivity using a mobile technology, the Allergy Diary. Methods: We undertook a 1-year prospective observational study in which 4 210 users and 32 585 days were monitored in 19 countries. Five visual analogue scales (VAS) assessed the daily burden of the disease (i.e., global evaluation, nose, eyes, asthma and work). Visual analogue scale levels <20/100 were categorized as "Low" burden and VAS levels ≥50/100 as "High" burden. Results: Visual analogue scales global measured levels assessing the global control of the allergic disease were significantly associated with allergic multimorbidity. Eight hypothesis-driven patterns were defined based on "Low" and "High" VAS levels. There were <0.2% days of Rhinitis Low and Asthma High or Conjunctivitis High patterns. There were 5.9% days with a Rhinitis High-Asthma Low pattern. There were 1.7% days with a Rhinitis High-Asthma High-Conjunctivitis Low pattern. A novel Rhinitis High-Asthma High-Conjunctivitis High pattern was identified in 2.9% days and had the greatest impact on uncontrolled VAS global measured and impaired work productivity. Work productivity was significantly correlated with VAS global measured levels. Conclusions: In a novel approach examining daily symptoms with mobile technology, we found considerable intra-individual variability of allergic multimorbidity including a previously unrecognized extreme pattern of uncontrolled multimorbidity