A novel sampling technique for monitoring atmospheric methane concentrations: A case study with livestock sources.

The substantial increase in the presence of greenhouse gases (GHGs) in the atmosphere has led to the development of several sampling techniques to quantify and characterize the sources of high global warming potential gas emissions. In this context, we developed a new method to estimate the time-averaged concentration of atmospheric methane that employs a long hose to collect a sample of gas by diffusion through one of its ends. We performed numerical simulations to illustrate the basis of our method and to determine the numerical factors required to estimate the time-averaged concentration of methane.

Is Dairy Effluent an Alternative for Maize Crop Fertigation in Semiarid Regions? An Approach to Agronomic and Environmental Effects.

The reuse of effluents from intensive dairy farms combined with localized irrigation techniques (fertigation) has become a promising alternative to increase crop productivity while reducing the environmental impact of waste accumulation and industrial fertilizers production. Currently, the reuse of dairy effluents through fertigation by subsurface drip irrigation (SDI) systems is of vital importance for arid regions but it has been poorly studied. The present study aimed to assess the greenhouse gas (GHG) emissions, soil properties, and crop yield of a maize crop fertigated with either treated dairy effluent or dissolved granulated urea applied through an SDI system at a normalized N application rate of 200 kg N ha.

Environmental and anthropogenic drivers of soil methane fluxes in forests: Global patterns and among-biomes differences.

Forest soils are the most important terrestrial sink of atmospheric methane (CH ). Climatic, soil and anthropogenic drivers affect CH fluxes, but it is poorly known the relative weight of each driver and whether all drivers have similar effects across forest biomes. We compiled a database of 478 in situ estimations of CH fluxes in forest soils from 191 peer-reviewed studies.

Atmospheric Methane Concentration Allows Estimating Natural Gas Leaks in Heating Systems in Tandil, Argentina.

Residential use of natural gas (NG) for heating and cooking purposes may contribute significantly to CH emissions to the atmosphere. To analyze whether the NG demand in the city of Tandil, Argentina, contributes to the increase in atmospheric CH concentration, we conducted systematic collections of time-integrated air samples for a year in six city sites with different population and built-up density. Some meteorological parameters and NG consumption were registered.

Temporal variation in methane emissions in a shallow lake at a southern mid latitude during high and low rainfall periods.

The global methane (CH) emission of lakes is estimated at between 6 and 16 % of total natural CH emissions. However, these values have a high uncertainty due to the wide variety of lakes with important differences in their morphological, biological, and physicochemical parameters and the relatively scarse data from southern mid-latitude lakes. For these reasons, we studied CH fluxes and CH dissolved in water in a typical shallow lake in the Pampean Wetland, Argentina, during four periods of consecutive years (April 2011-March 2015) preceded by different rainfall conditions.