Nitrogen transformations with special reference to gaseous N losses from zero-tilled soils of Saskatchewan, Canada

AbstractSoil gross nitrogen (N) transformations could be influenced by land use change, however, the differences in inherent N transformations between different land use soils are still not well understood under subtropical conditions. In this study, an 15N tracing experiment was applied to determine the influence of land uses on gross N transformations in Regosols, widely distributed soils in Southwest China. Soil samples were taken from the dominant land use types of forestland and cropland. In the cropland soils, the gross autotrophic nitrification rates (mean 14.54 ± 1.66 mg N kg−1 day−1) were significantly higher, while the gross NH4+ immobilization rates (mean 0.34 ± 0.10 mg N kg−1 day−1) were significantly lower than those in the forestland soils (mean 1.99 ± 0.56 and 6.67 ± 0.74 mg N kg−1 day−1, respectively). The gross NO3− immobilization and dissimilatory NO3− reduction to NH4+ (DNRA) rates were not significantly different between the forestland and cropland soils. In comparison to the forestland soils (mean 0.51 ± 0.24), the cropland soils had significantly lower NO3− retention capacities (mean 0.01 ± 0.01), indicating that the potential N losses in the cropland soils were higher. The correlation analysis demonstrated that soil gross autotrophic nitrification rate was negatively and gross NH4+ immobilization rate was positively related to the SOC content and C/N ratio. Therefore, effective measures should be taken to increase soil SOC content and C/N ratio to enhance soil N immobilization ability and NO3− retention capacity and thus reduce NO3− losses from the Regosols.

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Well-Aerated Southern Appalachian Forest Soils Demonstrate Significant Potential for Gaseous Nitrogen Loss

Forests ◽

10.3390/f10121155 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1155

Author(s):

Peter Baas ◽

Jennifer D. Knoepp ◽

Jacqueline E. Mohan

Keyword(s):

Forest Soils ◽

Nitrogen Loss ◽

Elevation Gradient ◽

High Elevation ◽

N Cycling ◽

N Losses ◽

Northern Hardwood ◽

Southern Appalachian ◽

Nitrifier Denitrification ◽

Gaseous N Losses

Understanding the dominant soil nitrogen (N) cycling processes in southern Appalachian forests is crucial for predicting ecosystem responses to changing N deposition and climate. The role of anaerobic nitrogen cycling processes in well-aerated soils has long been questioned, and recent N cycling research suggests it needs to be re-evaluated. We assessed gross and potential rates of soil N cycling processes, including mineralization, nitrification, denitrification, nitrifier denitrification, and dissimilatory nitrate reduction to ammonium (DNRA) in sites representing a vegetation and elevation gradient in the U.S. Department of Agriculture (USDA) Forest Service Experimental Forest, Coweeta Hydrologic Laboratory in southwestern North Carolina, USA. N cycling processes varied among sites, with gross mineralization and nitrification being greatest in high-elevation northern hardwood forests. Gaseous N losses via nitrifier denitrification were common in all ecosystems but were greatest in northern hardwood. Ecosystem N retention via DNRA (nitrification-produced NO3 reduced to NH4) ranged from 2% to 20% of the total nitrification and was highest in the mixed-oak forest. Our results suggest the potential for gaseous N losses through anaerobic processes (nitrifier denitrification) are prevalent in well-aerated forest soils and may play a key role in ecosystem N cycling.

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The effect of dicyandiamide addition to cattle slurry on soil gross nitrogen transformations at a grassland site in Northern Ireland

The Journal of Agricultural Science ◽

10.1017/s0021859613000762 ◽

2013 ◽

Vol 152 (S1) ◽

pp. 125-136 ◽

Cited By ~ 3

Author(s):

K. L. McGEOUGH ◽

C. MÜLLER ◽

R. J. LAUGHLIN ◽

C. J. WATSON ◽

M. ERNFORS ◽

...

Keyword(s):

Northern Ireland ◽

Nitrification Inhibitor ◽

Organic N ◽

Ammonium Oxidation ◽

Nitrogen Transformations ◽

Cattle Slurry ◽

N Losses ◽

N Transformations ◽

Dominant Process ◽

Grassland Site

SUMMARYMany studies have shown the efficacy of the nitrification inhibitor dicyandiamide (DCD) in reducing nitrous oxide (N2O) emissions and nitrate (NO3−) leaching. However, there is no information on the effect of DCD on gross soil N transformations under field conditions, which is key information if it is to be used as a mitigation strategy to reduce N losses. The current field study was conducted to determine the effect of DCD on ten gross nitrogen (N) transformations in soil following cattle slurry (CS) application to grassland in Northern Ireland on three occasions (June 2010, October 2010 and March 2011).Ammonium (NH4+) oxidation (ONH4) was the dominant process in total NO3− production (ONH4+ONrec (oxidation of recalcitrant organic N to NO3−)) following CS application, accounting for 0·894–0·949. Dicyandiamide inhibited total NO3− production from CS by 0·781, 0·696 and 0·807 in June 2010, October 2010 and March 2011, respectively. The lower inhibition level in October 2010 was thought to be due to the higher rainfall and soil moisture content in that month compared to the other application times. As DCD strongly inhibited NH4+ oxidation following CS application, it also decreased the rate of total NO3− consumption, since less NO3− was formed. The rates of mineralization from recalcitrant organic-N (MNrec) were higher than from labile organic-N (MNlab) on all occasions. The DCD significantly increased total mineralization (MNrec+MNlab) following CS application in June 2010 and March 2011, but had no significant effect in October 2010. In contrast, the rate of immobilization of labile organic-N (INH4_Nlab) was higher than from recalcitrant organic-N (INH4_Nrec) on all occasions, accounting for 0·878–0·976 of total NH4+ immobilization from CS. The DCD significantly increased total immobilization (INH4_Nrec+INH4_Nlab) when CS was applied in June 2010, but had no significant effect at other times of the year.Dicyandiamide was shown to be a highly effective inhibitor of ammonium oxidation at this grassland site. Although there was evidence that it increased both NH4+ mineralization and immobilization following CS application, its effect on these processes was inconsistent. Further work is required to understand the reason for these inconsistent effects: future improvements in 15N tracer models may help.

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GASEOUS NITROGEN LOSSES FROM CONVENTIONAL AND CHEMICAL SUMMERFALLOW

Canadian Journal of Soil Science ◽

10.4141/cjss85-020 ◽

1985 ◽

Vol 65 (1) ◽

pp. 195-203 ◽

Cited By ~ 18

Author(s):

M. S. AULAKH ◽

D. A. RENNIE

Keyword(s):

Soil Moisture ◽

Field Studies ◽

Soil Core ◽

Gaseous Nitrogen ◽

N Losses ◽

Factors Affecting ◽

Major Factors ◽

Chemical Fallow ◽

Lower Slope ◽

Gaseous N Losses

The gaseous losses of N (N2O + N2) measured for 130 days (May-September 1983) from conventional fallow at Yorkton, Oxbow and Weyburn soil sites ranged from 9 to 11, 15 to 31 and 60 to 87 kgN∙ha−1 for upper, middle and lower slope positions, respectively. The corresponding values for chemical fallow were 18–28, 24–51, and 69–98 kgN∙ha−1. In both tillage systems, gaseous N losses increased in the order of upper < middle < lower slope positions and were associated with the variations in soil moisture. The results obtained from additional widely scattered field studies on chernozemic soils further confirmed that the more dense surface soil and relatively higher soil moisture (lower air-filled porosity) were the major factors affecting increased denitrification under chemical fallow. Volumetric soil moisture was the only factor which showed a very highly significant correlation with N2O emmisions. Key words: Acetylene inhibition-soil core technique, chemical fallow, denitrification, nitrification

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Nitrogen Release in Soils Amended with Different Organic and Inorganic Fertilizers under Contrasting Moisture Regimes: A Laboratory Incubation Study

Agronomy ◽

10.3390/agronomy11112163 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2163

Author(s):

Shihab Uddin ◽

Mohammad Rafiqul Islam ◽

Mohammad Mofizur Rahman Jahangir ◽

Mohammad Mojibur Rahman ◽

Sabry Hassan ◽

...

Keyword(s):

Soil Type ◽

N Mineralization ◽

Poultry Manure ◽

Order Kinetic ◽

Strongly Correlated ◽

N Losses ◽

N Application ◽

Moisture Regimes ◽

N Release ◽

Gaseous N Losses

Understanding nitrogen (N) release patterns and kinetics is a key challenge for improving N use efficiency in any agroecosystem. An incubation experiment was done to study the N release pattern and kinetics of contrasting soils amended with compost (CO), poultry manure (PM), rice husk biochar (RHB), poultry manure biochar (PMB) and cowdung (CD) combined with chemical fertilizer (integrated plant nutrient system, IPNS approach) under two moisture regimes, viz. field capacity (FC) and continuous standing water (CSW) at 25 °C for 120 days. Our results revealed that NH4+-N was the dominant under CSW conditions, whereas NO3−-N was dominant under FC conditions. Net mineral N data fitted well to the first order kinetic model. Both N release potential (N0) and rate constant (k) were greater in acidic soil than those of charland soil. The maximum N release varied between 24.90–76.29% of input depending on soil type and moisture status. N mineralization was strongly correlated with urea N application. PM and PMB mineralized in all soil and moisture conditions whereas N immobilization was observed in the case of RHB. N mineralization was strongly correlated with urea N application. Gaseous N losses were different for the organic amendments exhibiting more gaseous N losses in PM, CD and CO based IPNS whereas the lowest gaseous N loss was observed in PMB based IPNS. Biochar based IPNS increased soil pH in all conditions. Thus, the present study suggests that N release depends on soil type, soil moisture and type of organic amendment. However, CO, PM and CD based IPNS can be recommended for both acidic and charland soils in terms of N release as short duration crops will suffer from N deficiency if biochar based IPNS is used in the field.

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THE EFFECT OF VARIOUS CLOVER MANAGEMENT PRACTICES ON GASEOUS N LOSSES AND MINERAL N ACCUMULATION

Canadian Journal of Soil Science ◽

10.4141/cjss83-060 ◽

1983 ◽

Vol 63 (3) ◽

pp. 593-605 ◽

Cited By ~ 25

Author(s):

M. S. AULAKH ◽

D. A. RENNIE ◽

E. A. PAUL

Keyword(s):

Management Practices ◽

Nitrogen Accumulation ◽

Clay Loam ◽

N Losses ◽

Mineral N ◽

N Accumulation ◽

Gaseous Loss ◽

Second Year ◽

Inhibition Technique ◽

Gaseous N Losses

A 2-yr field study was carried out to assess gaseous losses of N as N2O + N2 from two Black Chernozemic soils, where during year 1 wheat was underseeded to clover and in year 2, the clover in late June was (a) green-manured and the field fallowed, (b) harvested for hay and then fallowed, or (c) harvested for hay and allowed to regrow. Gaseous losses during year 1 were small and ranged from 1.3 kg N∙ha−1 (Blaine Lake clay loam) to 4.7 kg N∙ha−1 (Hoey clay loam). Gaseous losses were somewhat higher during the second year, but differences between the various clover management practices were generally small. The contribution of lower soil horizons towards gaseous nitrogen losses were shown to be negligible. Soil moisture, mean air temperature, nitrate + nitrite, and ammonia N concentrations collectively accounted for 37–66% of the variations in N2O fluxes. It is concluded that incorporation of clover followed by a partial fallow results in substantially less gaseous loss of nitrogen than the standard summerfallowing practice, and at the same time significantly increases mineral nitrogen accumulation in the soil. Key words: Acetylene inhibition technique, denitrification, nitrification, mineralization, green manuring

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Increasing N use efficiency while decreasing gaseous N losses in a non-tilled wheat (Triticum aestivum L.) crop using a double inhibitor

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2021.107546 ◽

2021 ◽

Vol 319 ◽

pp. 107546

Author(s):

Guillermo Guardia ◽

Sandra García-Gutiérrez ◽

Rocío Rodríguez-Pérez ◽

Jaime Recio ◽

Antonio Vallejo

Keyword(s):

Triticum Aestivum ◽

Triticum Aestivum L ◽

N Use Efficiency ◽

N Losses ◽

Use Efficiency ◽

N Use ◽

Gaseous N Losses

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Litter Controls Earthworm-Mediated Carbon and Nitrogen Transformations in Soil from Temperate Riparian Buffers

Applied and Environmental Soil Science ◽

10.1155/2014/329031 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Maria Kernecker ◽

Joann K. Whalen ◽

Robert L. Bradley

Keyword(s):

Vegetation Management ◽

Riparian Buffers ◽

Litter Type ◽

Nitrogen Transformations ◽

Microcosm Experiment ◽

Reed Canarygrass ◽

N Losses ◽

Carbon And Nitrogen ◽

C And N ◽

Native Tree Species

Nutrient cycling in riparian buffers is partly influenced by decomposition of crop, grass, and native tree species litter. Nonnative earthworms in riparian soils in southern Quebec are expected to speed the processes of litter decomposition and nitrogen (N) mineralization, increasing carbon (C) and N losses in gaseous forms or via leachate. A 5-month microcosm experiment evaluated the effect ofAporrectodea turgidaon the decomposition of 3 litter types (deciduous leaves, reed canarygrass, and soybean stem residue). Earthworms increased CO2and N2O losses from microcosms with soybean residue, by 112% and 670%, respectively, but reduced CO2and N2O fluxes from microcosms with reed canarygrass by 120% and 220%, respectively. Litter type controlled the CO2flux (soybean ≥ deciduous-mix litter = reed canarygrass > no litter) and the N2O flux (soybean ≥ no litter ≥ reed canarygrass > deciduous-mix litter). However, in the presence of earthworms, there was a slight increase in C and N gaseous losses of C and N relative to their losses via leachate, across litter treatments. We conclude that litter type determines the earthworm-mediated decomposition effect, highlighting the importance of vegetation management in controlling C and N losses from riparian buffers to the environment.

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