About the lab

- Estudio de gases de efecto invernadero (GEIs) y otros contaminantes atmosféricos de diversas fuentes y sumideros:
Flujos de GEIs en suelos bajo distintas coberturas vegetales;
Emisiones de CH4, CO2, NOx y SOx desde fuentes urbanas
Emisiones fugitivas de CH4 por uso de gas natural en centros urbanos
Emisiones de CH4 y N2O desde excretas y orina de animales en pastoreo o en feedlots
-Estudio de Procesos Avanzados de Oxidación aplicados al tratamiento químico de contaminantes difícilmente degradables en plantas de depuración biológica
- Desarrollo de tecnologías para recolección de muestras gaseosas y conservación de muestras de aire con trazas de distintos GEIs y desarrollo de cápsulas liberadoras de SF6, para medición de flujos de CH4 de rumiantes en pastoreo.

Featured research (13)

Evidence suggests that tree plantations change soil methane (CH 4) fluxes (magnitude and/or direction of the fluxes) compared to herbaceous land (i.e. afforestation effect) due to the effect of trees increasing methanotroph bacteria abundance and enhancing soil gas diffusivity. However, the magnitude of this afforestation effect is highly variable across studies. Here, we evaluated whether the variation in the afforestation effect depends on forestry management strategies, described by stand age and density, as well as taxonomic identity of the tree species, and the interaction with climatic conditions. To this end, we conducted a meta-analysis using 47 paired samples of afforested and contiguous herbaceous land from 14 studies located in different biomes worldwide. We found that afforestation predominantly increases the capacity of soil net CH 4 uptake (i.e. more negative fluxes) compared to herbaceous land, but the magnitude of this effect was highly heterogeneous across paired samples. This heterogeneity was explained by environmental conditions, but significant effects of forest stand age and density were also found proving the importance of forest management on this ecological service. Soil net CH 4 uptake following afforestation increases with increasing stand age. Although the stand stocking effect could be tested with a limited number of studies (24 out of the 47 paired samples), the results suggest that net CH 4 uptake decreases with tree stocking (stand density) in the range of values up to 1500 individuals per ha. No change in CH 4 fluxes was observed above this high stand density. Contrary to our expectations, no effect of taxonomic identity of the trees considering the most planted genera (Pinus and Eucalyptus) was observed in the average soil CH 4 fluxes. Furthermore, a significant correlation between the afforestation effect on soil water content and CH 4 flux suggests that the most plausible cause of the increased soil net CH 4 uptake is driven by the forest impact on soil desiccation, which in turn increases in sites with higher water limitation (i.e. higher potential evapotranspiration and high temporal rainfalls variations within the ranges of the available studies). Finally, our study provides evidence that by modifying rotation time and stand stocking, afforested land may increase its environmental service as a sink of atmospheric CH 4 .
Upland soils are the main methane (CH 4) biological sink, and may be affected by land-use change. Changes in land uses and soil management affect soil properties that control diffusion of gases, which in combination with microbial activity, determine CH 4 flux (fCH 4) through the soil. Net CH 4 fluxes and diffusivity-estimated by the CH 4 diffusion coefficient-were measured in three common land uses typical from Pampean plains, South America (natural grassland NG; Eucalyptus globulus Labill. afforestation E; and agricultural land AL: oat, soybean and red clover in successive cultivation) during two years (March 2017-March 2019). Methane fluxes in the soil-atmosphere interface were measured using the static chamber technique, and a diffusion model was applied to estimate soil CH 4 diffusivity from soil porosity. We aimed to quantify the effect of land use change (both E and AL vs. NG, the reference system) on fCH 4 and gas diffusivity due to changes in the soil parameters. Soils were net sinks in the three land uses, with mean CH 4 flux higher in the afforestation, intermediate in the natural grassland and lower in the agricultural land (− 10.99 ± 5.85, − 8.9 ± 5.32 and − 4.58 ± 4.19 ng CH 4 m − 2 s − 1 , respectively). CH 4 fluxes varied significantly through seasons and space coinciding with variations in water-filled pore space and air-filled pore space variables (ρ > 0.7 and <− 0.7 respectively; p < 0.05). Land-use change metric for methane flux ΔfCH 4 was − 2.1 ± 3.7 and 4.4 ± 2.5 for NG-E and NG-AL, respectively, indicating a significant increment in net CH 4 uptake when the natural grassland is afforested and a decrease when it was converted to agricultural use. This change was mainly explained by changes in soil physical properties (bulk density, soil water content, WFPS and air filled porosity). In relation to this, soil CH 4 diffusion coefficient followed the same pattern as fCH 4 (0.024 ± 0.011; 0.015 ± 0.007 and 0.008 ± 0.007 cm 2 s − 1 for E, NG and AL respectively); and allowed us to recalculate mean CH 4 fluxes. Theoretical and in situ measured CH 4 fluxes were similar and followed the same patterns across land uses, suggesting the possibility to determine CH 4 fluxes by means of simple measures of soil properties (bulk density and soil water content) and soil CH 4 gradient concentration.
There is an overall trend in urban methane (CH 4 ) emissions due to the presence of several sources; however, differences exist between cities, and therefore further local research should be undertaken. The present study analyzes the spatiotemporal variation in atmospheric CH 4 concentrations during a year at ten sampling sites in the urban core of a medium-sized city. The mean annual atmospheric CH 4 concentrations varied between 2.02 ppm and 5.45 ppm; the maximum concentrations were found in a site close to a wastewater treatment plant (WWTP), presenting a significant increase toward the summer. In the rest of the sites, the maximum concentrations were recorded in the coldest months due to the influence of combustion sources dependent on natural gas (NG). An exploratory regression analysis was performed, in which the variables “homes connected to the gas network” and “distance from compressed NG stations” each explained 66 and 65% of the spatial variation of the atmospheric CH 4 concentrations at the 9 sites (excluding that one nearest the WWTP). The results show the need to prevent NG leaks in all urban areas to reduce the emissions of this potent greenhouse gas, which, at the same time, will provide economic benefits for the sectors involved.
Latin America and Caribbean (LAC) is a developing region characterized for its importance for global food security, producing 23 and 11% of the global beef and milk production, respectively. The region's ruminant livestock sector however, is under scrutiny on environmental grounds due to its large contribution to enteric methane (CH4) emissions and influence on global climate change. Thus, the identification of effective CH4 mitigation strategies which do not compromise animal performance is urgently needed, especially in context of the Sustainable Development Goals (SDG) defined in the Paris Agreement of the United Nations. Therefore, the objectives of the current study were to: 1) collate a database of individual sheep, beef and dairy cattle records from enteric CH4 emission studies conducted in the LAC region, and 2) perform a meta-analysis to identify feasible enteric CH4 mitigation strategies, which do not compromise animal performance. After outlier's removal, 2745 animal records (65% of the original data) from 103 studies were retained (from 2011 to 2021) in the LAC database. Potential mitigation strategies were classified into three main categories (i.e., animal breeding and dietary and rumen manipulation) and up to three subcategories, totaling 34 evaluated strategies. A meta-analysis was performed according to a random effects model weighted by inverse variance (Comprehensive Meta-Analysis V3.3.070). Six strategies decreased at least one enteric CH4 metric and simultaneously increased milk yield (MY; dairy cattle) or average daily gain (ADG; beef cattle and sheep). The breed composition F1 Holstein × Gyr decreased CH4 emission per MY (CH4IMilk) while increasing MY by 99%. Adequate strategies of grazing management under continuous and rotational stocking decreased CH4IGain by 22 and 35%, while increasing ADG by 22 and 71%, respectively. Increased dietary protein concentration, and increased concentrate level through cottonseed meal inclusion, decreased CH4IMilk and CH4IGain by 10 and 20% and increased MY and ADG by 12 and 31%, respectively. Lastly, increased feeding level decreased CH4IGain by 37%, while increasing ADG by 171%. The identified effective mitigation strategies can be adopted by livestock producers according to their specific needs and aid LAC countries in achieving SDG as defined in the Paris Agreement.
Feeding management represents an opportunity to improve cattle performance in grazing-based production systems and to mitigate emissions of greenhouse gases (GHG) from livestock production. However, it is unclear how diet affects GHG emissions from dung patches left by grazing cattle. In this study, we evaluated the impact of supplementing the diet of grazing beef steers with maize grain on methane (CH4) and nitrous oxide (N2O) emissions from dung patches, and estimated the corresponding emission factors (EF). Gas fluxes from dung and soil were monitored over 125 days, using the static chamber technique. Dung from supplemented grazing steers produced significantly lower CH4 and higher N2O emissions (1.7 g CH4-C/m² and 0.4 g N2O-N/m²) than dung from non-supplemented steers (4.0 g CH4-C/m² and 0.1 g N2O-N/m²). Total GHG emissions from dung showed a tendency to be lower with maize grain supplementation (47.8 and 63.5 ± 5.9 g CO2eq/head/d for supplemented and non-supplemented steers, respectively),. The EF values (0.8 g CH4/kg volatile solids (VS) and 0.09% N2O) were lower than the default values established by IPCC 2006, but comparable to those established by IPCC 2019. Thus, the IPCC 2019 EF values should be used for GHG inventories in the study region (Argentina) until more region-specific values are obtained. Using local data, this study showed that supplementing the diet of grazing steers can reduce dung GHG emissions. Further studies are needed to assess the full implications of dietary supplementation on GHG emissions at farm level.

Lab head

M. Paula Juliarena
Department
  • Departamento de Ciencias Físicas y Ambientales
About M. Paula Juliarena
  • Maria Juliarena currently works at the Departamento de Ciencias Físicas y Ambientales, National University of the Center of the Buenos Aires Province. Maria does research in Environmental Chemistry. Their most recent publication is 'Afforested sites in a temperate grassland region: influence on soil properties and methane uptake'.

Members (9)

Sergio Alejandro Guzmán
  • National University of the Center of the Buenos Aires Province
Banira Lombardi
  • National University of the Center of the Buenos Aires Province
Maria Eugenia Priano
  • National University of the Center of the Buenos Aires Province
Victoria Susana Fusé
  • National University of the Center of the Buenos Aires Province
Andrea Mariela Berkovic
  • National University of the Center of the Buenos Aires Province
María De Bernardi
  • National University of the Center of the Buenos Aires Province
Carla Stadler
  • National University of the Center of the Buenos Aires Province
Ezequiel Teran
  • National University of the Center of the Buenos Aires Province
Eugenia Priano
Eugenia Priano
  • Not confirmed yet
Victoria Susana Fusé
Victoria Susana Fusé
  • Not confirmed yet
david kantlen
david kantlen
  • Not confirmed yet