The relationship between nitrous oxide (N2O) flux and N availability in agricultural ecosystems is usually assumed to be linear, with the same proportion of nitrogen lost as N2O regardless of input level. We conducted a 3-year, high-resolution N fertilizer response study in southwest Michigan USA to test the hypothesis that N2O fluxes increase mainly in response to N additions that exceed crop ...

Biological nitrification inhibition is a plant-mediated rhizosphere process where natural inhibitors can be produced and released by roots to suppress nitrifier activity in soil. Nitrification one of the critical soil processes nitrogen (N) cycle, but unrestricted rapid agricultural systems result major losses N from plant–soil system (i.e., NO3− leaching gaseous emissions). In this study, we e...

A sensitive NO2- biosensor that is based on bacterial reduction of NO2- to N2O and subsequent detection of the N2O by a built-in electrochemical N2O sensor was developed. Four different denitrifying organisms lacking NO3- reductase activity were assessed for use in the biosensor. The relevant physiological aspects examined included denitrifying characteristics, growth rate, NO2- tolerance, and ...

The methane (CH4) and nitrous oxide (N2O) exchange of a temperate mountain grassland near Neustift, Austria, was measured during 2010-2012 over a time period of 22 months using the eddy covariance method. Exchange rates of both compounds at the site were low, with 97% of all half-hourly CH4 and N2O fluxes ranging between ±200 and ±50 ng m-2 s-1, respectively. The meadow acted as a sink for both...

BACKGROUND A three-year field experiment was conducted to examine the responses of corn yield and soil nitrous oxide (N2O) emission to various management practices in middle Tennessee. METHODOLOGY/PRINCIPAL FINDINGS The management practices include no-tillage + regular applications of urea ammonium nitrate (NT-URAN); no-tillage + regular applications of URAN + denitrification inhibitor (NT-in...

Constructed wetlands (CW) can efficiently remove nitrogen from polluted agricultural run-off, however, a potential caveat is nitrous oxide (N2O), harmful greenhouse gas and stratospheric ozone depleter. During five sampling campaigns, we measured N2O fluxes 0.53 ha off-stream CW treating nitrate-rich water the intensively fertilized watershed in Rampillon, France, using automated chambers with ...

The objectives of this study were to test the effects of soil temperature, flooding, and raw organic matter input on N2O emissions in a soil sampled at Hongze Lake wetland, Jiangsu Province, China. The treatments studied were-peat soil (I), peat soil under flooding (II), peat soil plus raw organic matter (III), and peat soil under flooding plus organic matter. These four treatments were incubat...

Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha(-1) bio...

We modeled the expected range of seasonal and annual N2O flux from temperate, grain agroecosystems using Monte Carlo sampling of N2O flux field observations. This analysis is complimentary to mechanistic biogeochemical model outcomes and provides an alternative method of estimating N2O flux. Our analysis produced a range of annual N2O gas flux estimates with mean values overlapping with results...

UNLABELLED Microbial activities in soils, such as (incomplete) denitrification, represent major sources of nitrous oxide (N2O), a potent greenhouse gas. The key enzyme for mitigating N2O emissions is NosZ, which catalyzes N2O reduction to N2. We recently described "atypical" functional NosZ proteins encoded by both denitrifiers and nondenitrifiers, which were missed in previous environmental su...