Effects of step-feed on long-term performances and N2O emissions of partial nitrifying granules

The rising atmospheric CO2 concentrations have effects on the worldwide ecosystems such as an increase in biomass production as well as changing soil processes and conditions. Since this affects the ecosystem’s net balance of greenhouse gas emissions, reliable projections about the CO2 impact are required. Deterministic models can capture the interrelated biological, hydrological, and biogeochemical processes under changing CO2 concentrations if long-term observations for model testing are provided. We used 13 years of data on above-ground biomass production, soil moisture, and emissions of CO2 and N2O from the Free Air Carbon dioxide Enrichment (FACE) grassland experiment in Giessen, Germany. Then, the LandscapeDNDC ecosystem model was calibrated with data measured under current CO2 concentrations and validated under elevated CO2. Depending on the hydrological conditions, different CO2 effects were observed and captured well for all ecosystem variables but N2O emissions. Confidence intervals of ensemble simulations covered up to 96% of measured biomass and CO2 emission values, while soil water content was well simulated in terms of annual cycle and location-specific CO2 effects. N2O emissions under elevated CO2 could not be reproduced, presumably due to a rarely considered mineralization process of organic nitrogen, which is not yet included in LandscapeDNDC.

Download Full-text

Long-term organic and inorganic fertilization alters temperature sensitivity of potential N2O emissions and associated microbes

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2015.11.005 ◽

2016 ◽

Vol 93 ◽

pp. 131-141 ◽

Cited By ~ 106

Author(s):

Peiyuan Cui ◽

Fenliang Fan ◽

Chang Yin ◽

Alin Song ◽

Pingrong Huang ◽

...

Keyword(s):

Temperature Sensitivity ◽

N2o Emissions

Download Full-text

Long-term measurements of N2O emissions

Energy Conversion and Management ◽

10.1016/0196-8904(95)00333-9 ◽

1996 ◽

Vol 37 (6-8) ◽

pp. 1279-1284 ◽

Cited By ~ 5

Author(s):

A. Vermoesen ◽

O. Van Cleemput ◽

G. Hofman

Keyword(s):

N2o Emissions

Download Full-text

Management Practices of Miscanthus × giganteus Strongly Influence Soil Properties and N2O Emissions Over the Long Term

BioEnergy Research ◽

10.1007/s12155-016-9796-1 ◽

2016 ◽

Vol 10 (1) ◽

pp. 208-224 ◽

Cited By ~ 8

Author(s):

Céline Peyrard ◽

Fabien Ferchaud ◽

Bruno Mary ◽

Eric Gréhan ◽

Joël Léonard

Keyword(s):

Soil Properties ◽

Management Practices ◽

N2o Emissions ◽

Miscanthus Giganteus

Download Full-text

Linkage of N2O emissions to the abundance of soil ammonia oxidizers and denitrifiers in purple soil under long-term fertilization

Soil Science & Plant Nutrition ◽

10.1080/00380768.2015.1049930 ◽

2015 ◽

Vol 61 (5) ◽

pp. 799-807 ◽

Cited By ~ 4

Author(s):

Zhixin Dong ◽

Bo Zhu ◽

Keke Hua ◽

Yan Jiang

Keyword(s):

Purple Soil ◽

N2o Emissions ◽

Ammonia Oxidizers

Download Full-text

Short- and long-term temperature responses of soil denitrifier net N<sub>2</sub>O efflux rates, inter-profile N<sub>2</sub>O dynamics, and microbial genetic potentials

SOIL ◽

10.5194/soil-6-399-2020 ◽

2020 ◽

Vol 6 (2) ◽

pp. 399-412

Author(s):

Kate M. Buckeridge ◽

Kate A. Edwards ◽

Kyungjin Min ◽

Susan E. Ziegler ◽

Sharon A. Billings

Keyword(s):

Mineral Soil ◽

Mean Annual Temperature ◽

N2o Emissions ◽

Soil Horizons ◽

N2o Reduction ◽

Short Term ◽

N2o Production ◽

Short Term Exposure ◽

Temperature Responses

Abstract. Production and reduction of nitrous oxide (N2O) by soil denitrifiers influence atmospheric concentrations of this potent greenhouse gas. Accurate projections of the net N2O flux have three key uncertainties: (1) short- vs. long-term responses to warming, (2) interactions among soil horizons, and (3) temperature responses of different steps in the denitrification pathway. We addressed these uncertainties by sampling soil from a boreal forest climate transect encompassing a 5.2 ∘C difference in the mean annual temperature and incubating the soil horizons in isolation and together at three ecologically relevant temperatures in conditions that promote denitrification. Both short-term exposure to warmer temperatures and long-term exposure to a warmer climate increased N2O emissions from organic and mineral soils; an isotopic tracer suggested that an increase in N2O production was more important than a decline in N2O reduction. Short-term warming promoted the reduction of organic horizon-derived N2O by mineral soil when these horizons were incubated together. The abundance of nirS (a precursor gene for N2O production) was not sensitive to temperature, whereas that of nosZ clade I (a gene for N2O reduction) decreased with short-term warming in both horizons and was higher from a warmer climate. These results suggest a decoupling of gene abundance and process rates in these soils that differs across horizons and timescales. In spite of these variations, our results suggest a consistent, positive response of denitrifier-mediated net N2O efflux rates to temperature across timescales in these boreal forests. Our work also highlights the importance of understanding cross-horizon N2O fluxes for developing a predictive understanding of net N2O efflux from soils.

Download Full-text

Greenhouse gas emissions from fen soils used for forage production in northern Germany

Biogeosciences ◽

10.5194/bg-13-5221-2016 ◽

2016 ◽

Vol 13 (18) ◽

pp. 5221-5244 ◽

Cited By ~ 15

Author(s):

Arne Poyda ◽

Thorsten Reinsch ◽

Christof Kluß ◽

Ralf Loges ◽

Friedhelm Taube

Keyword(s):

Ghg Emissions ◽

Farming Systems ◽

Forage Yield ◽

N2o Emissions ◽

Net Energy ◽

Forage Production ◽

Climatic Impact ◽

Northern Germany ◽

Ch4 And N2o

Abstract. A large share of peatlands in northwestern Germany is drained for agricultural purposes, thereby emitting high amounts of greenhouse gases (GHGs). In order to quantify the climatic impact of fen soils in dairy farming systems of northern Germany, GHG exchange and forage yield were determined on four experimental sites which differed in terms of management and drainage intensity: (a) rewetted and unutilized grassland (UG), (b) intensive and wet grassland (GW), (c) intensive and moist grassland (GM) and (d) arable forage cropping (AR). Net ecosystem exchange (NEE) of CO2 and fluxes of CH4 and N2O were measured using closed manual chambers. CH4 fluxes were significantly affected by groundwater level (GWL) and soil temperature, whereas N2O fluxes showed a significant relation to the amount of nitrate in top soil. Annual balances of all three gases, as well as the global warming potential (GWP), were significantly correlated to mean annual GWL. A 2-year mean GWP, combined from CO2–C eq. of NEE, CH4 and N2O emissions, as well as C input (slurry) and C output (harvest), was 3.8, 11.7, 17.7 and 17.3 Mg CO2–C eq. ha−1 a−1 for sites UG, GW, GM and AR, respectively (standard error (SE) 2.8, 1.2, 1.8, 2.6). Yield-related emissions for the three agricultural sites were 201, 248 and 269 kg CO2–C eq. (GJ net energy lactation; NEL)−1 for sites GW, GM and AR, respectively (SE 17, 9, 19). The carbon footprint of agricultural commodities grown on fen soils depended on long-term drainage intensity rather than type of management, but management and climate strongly influenced interannual on-site variability. However, arable forage production revealed a high uncertainty of yield and therefore was an unsuitable land use option. Lowest yield-related GHG emissions were achieved by a three-cut system of productive grassland swards in combination with a high GWL (long-term mean ≤  20 cm below the surface).

Download Full-text