Potential nitrification activity reflects ammonia oxidising bacteria but not archaea activity across a soil-sediment gradient

Ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) are key drivers of nitrification in rainfed soil ecosystems. However, within a semi-arid region, the influence of different soil amendments on the composition of soil AOA and AOB communities and soil properties of rainfed maize is still unclear. Therefore, in this study, the abundance, diversity, and composition of AOA and AOB communities and the potential nitrification activity (PNA) was investigated across five soil treatments: no fertilization (NA), urea fertilizer (CF), cow manure (SM), corn stalk (MS), and cow manure + urea fertilizer (SC). The AOB amoA gene copy number was influenced significantly by fertilization treatments. The AOB community was dominated by Nitrosospira cluster 3b under the CF and SC treatments, and the AOA community was dominated by Nitrososphaera Group I.1b under the CF and NA amendments; however, manure treatments (SM, MS, and SC) did not exhibit such influence. Network analysis revealed the positive impact of some hub taxonomy on the abundance of ammonia oxidizers. Soil pH, NO3−-N, Module 3, biomass, and AOB abundance were the major variables that influenced the potential nitrification activity (PNA) within structural equation modeling. PNA increased by 142.98–226.5% under the treatments CF, SC, SM, and MS compared to NA. In contrast to AOA, AOB contributed dominantly to PNA. Our study highlights the crucial role of bacterial communities in promoting sustainable agricultural production in calcareous soils in semi-arid loess plateau environments.

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The nitrification inhibitor 3,4,-dimethylpyrazole phosphate strongly inhibits nitrification in coarse-grained soils containing a low abundance of nitrifying microbiota

Soil Research ◽

10.1071/sr15359 ◽

2017 ◽

Vol 55 (1) ◽

pp. 28 ◽

Cited By ~ 9

Author(s):

Elliott G. Duncan ◽

Cathryn A. O'Sullivan ◽

Anna K. Simonsen ◽

Margaret M. Roper ◽

Mark B. Peoples ◽

...

Keyword(s):

Nitrification Inhibitor ◽

Sandy Soils ◽

Coarse Grained ◽

Soil Nitrification ◽

Potential Nitrification ◽

High Nutrient ◽

Inhibition Of Nitrification ◽

Inhibitor Type ◽

Ammonia Oxidising Bacteria

The effectiveness of the nitrification inhibitor 3,4,-dimethylpyrazole phosphate (DMPP) on sandy soils containing low nitrifying microbial abundance has not been established. Two coarse-grained soils, representative of Western Australia’s agricultural zones, were incubated with 100mgNkg–1 soil, added as either urea, urea+DMPP or urea+nitrapyrin as an alternative nitrification inhibitor for comparative purposes. Ammonium (NH4+) and nitrate (NO3–) concentrations, potential nitrification rates (PNR) and the abundance of ammonia-oxidising bacteria (AOB) and archaea (AOA) were measured over time. Interactions between soil type and inhibitor type altered the extent of nitrification observed in these soils. When N was supplied as urea alone, NH4+-N concentrations decreased from 100mgNkg–1 soil to approximately 20mgNkg–1 soil in the high nutrient soil (Williams) and approximately 60mgNkg–1 soil in the low nutrient soil (Vasse). These differences were reflected in AOB abundance, which was higher (~105genecopiesg–1 soil) in Williams soil than in Vasse soil (<104genecopiesg–1 soil). This difference could have been attributable to differences in soil pH between Williams and Vasse (5.4 vs 4.0 respectively) and/or copper (Cu) availability (~1.5 vs ~0.5mgCukg–1 soil respectively), both of which have been demonstrated to reduce AOB abundance or limit nitrification. On the Williams soil, DMPP limited nitrification, resulting in approximately 80mgNkg–1 soil being retained as NH4+-N. Nitrapyrin was similarly effective for the first 56 days of incubation, but declined considerably in effectiveness between Days 56 and 100. Changes in soil nitrification rates were accompanied by changes in AOB abundance, which was below 103genecopiesg–1 soil when nitrification was impaired. Both DMPP and nitrapyrin inhibit nitrification via chelating Cu and, because these soils contained low Cu concentrations, it may be possible that interactions between DMPP, naturally low abundance of AOB and low Cu availability facilitated the long-term inhibition of nitrification in these soils.

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Response of Nitrosospira sp. Strain AF-Like Ammonia Oxidizers to Changes in Temperature, Soil Moisture Content, and Fertilizer Concentration

Applied and Environmental Microbiology ◽

10.1128/aem.01803-06 ◽

2006 ◽

Vol 73 (4) ◽

pp. 1166-1173 ◽

Cited By ~ 72

Author(s):

Sharon Avrahami ◽

Brendan J. M. Bohannan

Keyword(s):

Soil Moisture ◽

Soil Moisture Content ◽

Ammonia Oxidizing Bacteria ◽

Ammonia Oxidizers ◽

Grassland Soil ◽

Nitrification Activity ◽

Increased Temperature ◽

Potential Nitrification ◽

Temperature Potential ◽

Increasing Temperature

ABSTRACT Very little is known regarding the ecology of Nitrosospira sp. strain AF-like bacteria, a unique group of ammonia oxidizers within the Betaproteobacteria. We studied the response of Nitrosospira sp. strain AF-like ammonia oxidizers to changing environmental conditions by applying molecular methods and physiological measurements to Californian grassland soil manipulated in the laboratory. This soil is naturally high in Nitrosospira sp. strain AF-like bacteria relative to the much-better-studied Nitrosospira multiformis-like ammonia-oxidizing bacteria. Increases in temperature, soil moisture, and fertilizer interacted to reduce the relative abundance of Nitrosospira sp. strain AF-like bacteria, although they remained numerically dominant. The overall abundance of ammonia-oxidizing bacteria increased with increasing soil moisture and decreased with increasing temperature. Potential nitrification activity was altered by interactions among temperature, soil moisture, and fertilizer, with activity tending to be higher when soil moisture and temperature were increased. The increase in potential nitrification activity with increased temperature was surprising, given that the overall abundance of ammonia-oxidizing bacteria decreased significantly under these conditions. This observation suggests that (i) Nitrosospira sp. strain AF-like bacteria may respond to increased temperature with an increase in activity, despite a decrease in abundance, or (ii) that potential nitrification activity in these soils may be due to organisms other than bacteria (e.g., archaeal ammonia oxidizers), at least under conditions of increased temperature.

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Increased soil nitrogen supply enhances root-derived available soil carbon leading to reduced potential nitrification activity

Applied Soil Ecology ◽

10.1016/j.apsoil.2020.103842 ◽

2021 ◽

Vol 159 ◽

pp. 103842

Author(s):

Andrea Leptin ◽

David Whitehead ◽

Craig R. Anderson ◽

Keith C. Cameron ◽

Niklas J. Lehto

Keyword(s):

Soil Carbon ◽

Soil Nitrogen ◽

Nitrogen Supply ◽

Nitrification Activity ◽

Potential Nitrification ◽

Soil Nitrogen Supply

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Spatial distribution and rate of potential nitrification activity in two hill country pastures

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2006.68.2619 ◽

2006 ◽

pp. 369-373 ◽

Cited By ~ 2

Author(s):

S.A. Letica ◽

R. Tillman ◽

R. Littlejohn ◽

C.J. Hoogendoorn ◽

C.A.M. De Klein ◽

...

Keyword(s):

Spatial Distribution ◽

Best Management Practices ◽

Management Practices ◽

Preliminary Investigation ◽

N Losses ◽

N Application ◽

Hill Country ◽

Nitrification Potential ◽

Nitrification Activity ◽

Potential Nitrification

The purpose of this study was to conduct a preliminary investigation into the effect of increasing fertiliser- and excreta-N inputs on the spatial distribution and rate of potential nitrification activity in hill country pasture land at two sites, Invermay and Ballantrae. High nitrification rates could potentially limit N efficiency by increasing N losses through leaching and denitrification. Nitrification potentials (NP) were measured in camp sites and medium slopes of hill country soils receiving 0 kg N and 500 kg N/ha/yr over the previous 18 months. Nitrification potential was determined by calculating the rate of nitrate production (mg NO3-N/kg soil/h) by linear regression of soil solution concentrations, versus time. Nitrification potential was significantly higher at Invermay than at Ballantrae, which was likely due to a significantly lower soil pH at Ballantrae. At Invermay, NP increased with fertiliser-N application rate and in camp site soils. The fertiliser N effect was not observed at Ballantrae. However, soil NO3-N and NP was significantly greater in soils from camp sites than for soils from medium slopes. Best management practices for fertiliser-N application in hill country should make allowances for these factors to maximise farm efficiency and profitability. Keywords: hill country, nitrification potential, nitrogen fertiliser, stock behaviour, excreta-N, mineral-N, New Zealand

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