Short-term biotic removal of dissolved organic nitrogen (DON) compounds from soil solution and subsequent mineralisation in contrasting grassland soils

Crop tree management (CTM) is a widely applicable silviculture technology that is used to improve the performance of individual trees. However, only little information is available about the effects of the CTM regime on the soil microbial community structure. We conducted a study to explore the effects of short-term (five years) CTM on the soil bacterial and fungal diversity, community composition, and structure in the 0–10 cm soil layer in a Larix gmelinii (Rupr.) Kuzen. plantation. We set out to investigate the differential response of bacterial and fungal communities to variations in soil properties mediated by short-term CTM. Compared with the control plots, the soil microbial biomass carbon and microbial biomass nitrogen in CTM increased significantly by 64.2% and 32.3%, respectively. CTM significantly promoted the content of soil organic carbon, dissolved organic carbon, and nitrate nitrogen, and reduced the content of dissolved organic nitrogen. CTM changed the Shannon and Simpson indices of soil fungi to a remarkable extent but had little effect on the α diversity of bacterial communities. The bacterial β diversity was more sensitive to CTM than fungi. The relative abundance of Verrucomicrobiae (the dominant class of soil bacteria) in CTM was significantly increased by 78.2%, while the relative abundance of Agaricomycetes (dominant class for soil fungi) was reduced by 43.3%. We observed a significantly increased number of unique OTUs for soil fungi in the CTM plots. Redundancy analysis showed that dissolved organic carbon, soil moisture, and total phosphorus content significantly affected the composition of bacterial communities, while soil dissolved organic nitrogen, C/N, and total phosphorus drove the high variation in fungal community composition. Overall, our results emphasize the divergent response of soil bacterial and fungal communities in Larix gmelinii plantations to short-term CTM. We must pay more attention to the functional role of soil microbiota in future forest management.

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Short-term uptake of dissolved organic nitrogen by an axenic strain of Ulva pertusa (Chlorophyceae) using [15]N isotope measurements

Botanica Marina ◽

10.1515/bot.2004.026 ◽

2004 ◽

Vol 47 (3) ◽

Cited By ~ 7

Author(s):

Kenji Tarutani ◽

Yoko Niimura ◽

Takuji Uchida

Keyword(s):

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Ulva Pertusa ◽

Short Term ◽

Axenic Strain ◽

Isotope Measurements

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Effect of fertilization on composition and spatial distribution of dissolved organic nitrogen in paddy soil microbial systems

Plant Soil and Environment ◽

10.17221/533/2011-pse ◽

2012 ◽

Vol 58 (No. 3) ◽

pp. 128-134 ◽

Cited By ~ 5

Author(s):

H. Zhang ◽

Z. Zhao ◽

X. Yi ◽

Y. Lu ◽

L. Cao

Keyword(s):

Spatial Distribution ◽

Soil Solution ◽

Paddy Soil ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Diversity Index ◽

Organic Matter Content ◽

Significant Negative Correlation ◽

Matter Content ◽

Wiener Diversity Index

Dissolved organic nitrogen (DON) has high bioavailability and is an important source of soil nutrients. In order to determine the concentrations and the composition of DON in different depths (0–30 cm), and provide a theoretical basis for further deep research into the paddy soil nitrogen supply, experiments based on the lysimeter method were carried out to investigate the effect of fertilization on composition and spatial distribution of DON in paddy soil. Paddy soil was treated under chemical fertilization treatment (CT) and mixed fertilization treatment (MT). With methods of PCR-DGGE and HPLC-MS, the results of the experiments suggested that the samples in 10–20 cm and 20–30 cm under MT had significantly higher bacterial diversity than those under CT except in 0–10 cm. DON had a high percentage (63.1–79.9%) in N<sub>tot</sub> of soil solution. The results of the correlation analysis revealed that DON had a significant positive correlation with organic matter content, Shannon-Wiener diversity index (H') and a significant negative correlation with pH. The possible results of HPLC-MS identification of DON from paddy soil solution were that (a) 3-(4-thiazolyl)-l-alanine; (b) 2-phenylbenzimidazole-5-sulfonic acid; (c) 4-(2, 4-difluorophenyl)-3-nitrobenzene carbaldehyde; (d) fendizoic acid.    

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Faculty Opinions recommendation of Dissolved organic nitrogen dynamics in the Arctic Ocean.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717988876.793472785 ◽

2013 ◽

Author(s):

Robie Macdonald

Keyword(s):

Arctic Ocean ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Nitrogen Dynamics ◽

The Arctic ◽

The Arctic Ocean

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Wastewater Derived Dissolved Organic Nitrogen Removal using Integrated System of Biological Reactors and UV light Irradiation

Proceedings of the Water Environment Federation ◽

10.2175/193864716819713286 ◽

2016 ◽

Vol 2016 (9) ◽

pp. 4958-4968

Author(s):

Swati Sharma ◽

Donald L Tucker ◽

Halis Simsek

Keyword(s):

Nitrogen Removal ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Uv Light ◽

Integrated System ◽

Light Irradiation ◽

Uv Light Irradiation

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Electro-Oxidation to Convert Dissolved Organic Nitrogen and Soluble Non-Reactive Phosphorus to More Readily Removable and Recoverable Forms

Chemosphere ◽

10.1016/j.chemosphere.2021.130876 ◽

2021 ◽

pp. 130876

Author(s):

Synthia P. Mallick ◽

Donald R. Ryan ◽

Kaushik Venkiteshwaran ◽

Patrick J. McNamara ◽

Brooke K. Mayer

Keyword(s):

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Electro Oxidation ◽

Reactive Phosphorus

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Benthic fluxes of dissolved organic nitrogen in the lower St. Lawrence estuary and implications for selective organic matter degradation

Biogeosciences ◽

10.5194/bg-10-7609-2013 ◽

2013 ◽

Vol 10 (11) ◽

pp. 7609-7622 ◽

Cited By ~ 13

Author(s):

M. Alkhatib ◽

P. A. del Giorgio ◽

Y. Gelinas ◽

M. F. Lehmann

Keyword(s):

Organic Matter ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Bottom Water ◽

Estuarine Sediments ◽

Internal Source ◽

Lawrence Estuary ◽

Element Partitioning ◽

Sediment Porewaters ◽

St Lawrence Estuary

Abstract. The distribution of dissolved organic nitrogen (DON) and carbon (DOC) in sediment porewaters was determined at nine locations along the St. Lawrence estuary and in the gulf of St. Lawrence. In a previous manuscript (Alkhatib et al., 2012a), we have shown that this study area is characterized by gradients in the sedimentary particulate organic matter (POM) reactivity, bottom water oxygen concentrations, and benthic respiration rates. Based on the porewater profiles, we estimated the benthic diffusive fluxes of DON and DOC in the same area. Our results show that DON fluxed out of the sediments at significant rates (110 to 430 μmol m−2 d−1). DON fluxes were positively correlated with sedimentary POM reactivity and varied inversely with sediment oxygen exposure time (OET), suggesting direct links between POM quality, aerobic remineralization and the release of DON to the water column. DON fluxes were on the order of 30 to 64% of the total benthic inorganic fixed N loss due to denitrification, and often exceeded the diffusive nitrate fluxes into the sediments. Hence they represented a large fraction of the total benthic N exchange, a result that is particularly important in light of the fact that DON fluxes are usually not accounted for in estuarine and coastal zone nutrient budgets. In contrast to DON, DOC fluxes out of the sediments did not show any significant spatial variation along the Laurentian Channel (LC) between the estuary and the gulf (2100 ± 100 μmol m−2 d−1). The molar C / N ratio of dissolved organic matter (DOM) in porewater and the overlying bottom water varied significantly along the transect, with lowest C / N in the lower estuary (5–6) and highest C / N (> 10) in the gulf. Large differences between the C / N ratios of porewater DOM and POM are mainly attributed to a combination of selective POM hydrolysis and elemental fractionation during subsequent DOM mineralization, but selective adsorption of DOM to mineral phases could not be excluded as a potential C / N fractionating process. The extent of this C- versus N- element partitioning seems to be linked to POM reactivity and redox conditions in the sediment porewaters. Our results thus highlight the variable effects selective organic matter (OM) preservation can have on bulk sedimentary C / N ratios, decoupling the primary source C / N signatures from those in sedimentary paleoenvironmental archives. Our study further underscores that the role of estuarine sediments as efficient sinks of bioavailable nitrogen is strongly influenced by the release of DON during early diagenetic reactions, and that DON fluxes from continental margin sediments represent an important internal source of N to the ocean.

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