Nitrogen budgets in Japan from 2000 to 2015: Decreasing trend of nitrogen loss to the environment and the challenge to further reduce nitrogen waste

Abstract Studies on the chronic low dissolved oxygen problems encountered under winter ice in the Red Deer River have generally been unable to account for dissolved oxygen depletion in terms of known manmade inputs. An experimental program was developed to assess the possible nature and approximate bounds of oxygen demand due to natural organic runoff carried to the Red Deer River by a small tributary stream, the Blindman River. The study employed an electrolytic respirometer on stream water samples subjected to prior concentration by vacuum evaporation. Evaluation of carbon and nitrogen budgets in conjunction with the measured oxygen demand indicate that biochemical oxygen demand is originating with natural organic runoff in tributaries of the Red Deer River. The results provide a basis for estimation of the possible contribution to the observed oxygen demand in the Red Deer River originating from natural organic runoff.

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Foliar Urea with N-(n-butyl) Thiophosphoric Triamide for Sustainable Yield and Quality of Pineapple in a Controlled Environment

Sustainability ◽

10.3390/su13126880 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6880

Author(s):

Mohammad Amdadul Haque ◽

Siti Zaharah Sakimin ◽

Phebe Ding ◽

Noraini Md. Jaafar ◽

Mohd Khanif Yusop ◽

...

Keyword(s):

Nitrogen Loss ◽

Growth Yield ◽

Fruit Weight ◽

Soluble Solids ◽

Urea Solution ◽

Urease Inhibitor ◽

N Losses ◽

N Accumulation ◽

Yield And Quality

In agricultural production, nitrogen loss leads to economic loss and is a high environmental risk affecting plant growth, yield, and quality. Use of the N fertilizer with a urease inhibitor is thus necessary to minimize N losses and increase the efficiency of N. This study aimed to evaluate the effects of N-(n-butyl) Thiophosphoric Triamide (NBPT) on the growth, yield, and quality of pineapple. The experiment involved two foliar fertilizer treatments: 1% (w/v) urea solution with NBPT (2.25 mL kg−1 urea) was treated as NLU (NBPT Liquid Urea), and the same concentration of urea without NBPT served as the control. Both were applied 12 times, starting 1 month after planting (MAP) and continuing once a month for 12 months. The application of urea with NBPT notably increased the above-ground dry biomass per plant (20% and 10% at 8 and 12 MAP, respectively), leaf area per plant (23% and 15% at 8 and 12 MAP, respectively), N accumulation per plant (10%), PFPN (Partial Factor Productivity) (13%), and average fruit weight (15%) compared to the treatment with urea alone (control). The analysis of quality parameters indicated that urea with NBPT improves TSS (Total Soluble Solids) (19%), ascorbic acid (10%), and sucrose (14%) but reduces the total organic acid content (21%) in pineapple. When using urea with a urease inhibitor (NBPT), there was a significant improvement in growth, yield, quality, and nitrogen use efficiency, with the additional benefit of reduced nitrogen losses, in combination with easy handling. Hence, urea with a urease inhibitor can be used as a viable alternative for increasing pineapple yield by boosting growth with better fruit quality.

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Urban nitrogen budgets: flows and stock changes of potentially polluting nitrogen compounds in cities and their surroundings – a review

Journal of Integrative Environmental Sciences ◽

10.1080/1943815x.2020.1841241 ◽

2020 ◽

Vol 17 (1) ◽

pp. 57-71

Author(s):

Wilfried Winiwarter ◽

Barbara Amon ◽

Zhaohai Bai ◽

Andrzej Greinert ◽

Katrin Kaltenegger ◽

...

Keyword(s):

Nitrogen Compounds ◽

Nitrogen Budgets

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Microbial niche differentiation explains nitrite oxidation in marine oxygen minimum zones

The ISME Journal ◽

10.1038/s41396-020-00852-3 ◽

2021 ◽

Author(s):

Xin Sun ◽

Claudia Frey ◽

Emilio Garcia-Robledo ◽

Amal Jayakumar ◽

Bess B. Ward

Keyword(s):

Nitrogen Loss ◽

Niche Differentiation ◽

Nitrite Reduction ◽

Nitrite Oxidation ◽

Fixed Nitrogen ◽

Anoxic Waters ◽

Biogeochemical Models ◽

Nitrite Oxidizing Bacteria ◽

Oxygen Addition ◽

Oxygen Minimum

AbstractNitrite is a pivotal component of the marine nitrogen cycle. The fate of nitrite determines the loss or retention of fixed nitrogen, an essential nutrient for all organisms. Loss occurs via anaerobic nitrite reduction to gases during denitrification and anammox, while retention occurs via nitrite oxidation to nitrate. Nitrite oxidation is usually represented in biogeochemical models by one kinetic parameter and one oxygen threshold, below which nitrite oxidation is set to zero. Here we find that the responses of nitrite oxidation to nitrite and oxygen concentrations vary along a redox gradient in a Pacific Ocean oxygen minimum zone, indicating niche differentiation of nitrite-oxidizing assemblages. Notably, we observe the full inhibition of nitrite oxidation by oxygen addition and nitrite oxidation coupled with nitrogen loss in the absence of oxygen consumption in samples collected from anoxic waters. Nitrite-oxidizing bacteria, including novel clades with high relative abundance in anoxic depths, were also detected in the same samples. Mechanisms corresponding to niche differentiation of nitrite-oxidizing bacteria across the redox gradient are considered. Implementing these mechanisms in biogeochemical models has a significant effect on the estimated fixed nitrogen budget.

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Strong turbulence accelerates sediment nitrification-denitrification for nitrogen loss in shallow lakes

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.143210 ◽

2020 ◽

pp. 143210

Author(s):

Lin Zhu ◽

Wenqing Shi ◽

Jian Zhou ◽

Jianghua Yu ◽

Lingwei Kong ◽

...

Keyword(s):

Shallow Lakes ◽

Nitrogen Loss ◽

Strong Turbulence

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Spatiotemporal Dynamics of Nitrogen Budgets under Anthropogenic Activities in Metropolitan Areas

Sustainability ◽

10.3390/su13042006 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2006

Author(s):

Ning Ding ◽

Jingfeng Zhu ◽

Xiao Li ◽

Xiangrong Wang

Keyword(s):

Anthropogenic Activities ◽

River System ◽

Yangtze River Delta ◽

Fertilizer Efficiency ◽

Land Use Pattern ◽

Human Disturbances ◽

Nitrogen Budgets ◽

Metropolitan Regions ◽

Close Relationship ◽

Anthropogenic Nitrogen

The rapid growth of metropolitan regions is closely associated with high nitrogen (N) flows, which is known as the most important reason for widespread water pollution. It is, therefore, crucial to explore the spatiotemporal patterns of N budgets under intensive human activity. In this study, we estimated the long-term (2000–2015) N budgets by integrating the net anthropogenic nitrogen input (NANI) and the export coefficient model (ECM) in the Yangtze River Delta Urban Agglomeration (YRDUA), a typical metropolitan area with strong human disturbances. The results revealed that the NANI decreased by 10% from 2000 to 2015, while N exports showed a 6% increase. Hotspots for N budgets were found in the northeastern areas, where cropland and construction land were dominant. The linear regression showed a close relationship between the NANI and N export, and about 18% of the NANI was exported into the river system. By revealing the critical sources and drivers of N budgets over time, our work aimed to provide effective information for regional policy on nitrogen management. Future strategies, such as improving the fertilizer efficiency, optimizing the land use pattern, and controlling the population density, are necessary in order to address the environmental challenge concerns of excessive N.

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