Effects of N Fertilizer Application on Soil N2O Emissions and CH4 Uptake: A Two-Year Study in an Apple Orchard in Eastern China

Negative pressure irrigation (NPI) to grow crops reduces the application of fertilizer and water while also promoting yield and quality. However, plantation vegetables usually require a large input of nitrogen (N) fertilizer in a greenhouse setting, which will lower the soil quality and accelerate the emission of greenhouse gases. Therefore, the purpose of this research was to explore planting lettuce under an NPI system that retrenches N fertilizer application and mitigates N2O emissions compared with conventional irrigation (CI). This research proved that under NPI conditions, nitrate and ammonium fluctuated slightly in the soil, stabilizing in the range of 18–28 mg kg−1, while that of CI was 20–55 mg kg−1. The NPI alleviated N2O emissions, and NPI-N150 and NPI-N105 decreased them by 18% and 32%, respectively, compared with those for CI-N150. The main explanation was that the NPI inhibited the formation of NO3−-N, reduced the copies number of AOA and AOB as well as the abundance of Nitrospira in the soil, and weakened the soil nitrate reductase and urease activities. The results of this research provide a reliable scientific method for reducing the use of water and N fertilizer while cultivating lettuce, as well as for reducing N2O emissions from agricultural facilities.

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Nitrous oxide emission from agricultural soils in response to nitrification inhibitor and N-fertilizer amount

10.5194/egusphere-egu21-8135 ◽

2021 ◽

Author(s):

Azeem Tariq ◽

Klaus Steenberg Larsen ◽

Line Vinther Hansen ◽

Lars Stoumann Jensen ◽

Sander Bruun

Keyword(s):

Nitrous Oxide ◽

Temporal Dynamics ◽

Agricultural Soils ◽

Spring Barley ◽

Fertilizer Application ◽

N Fertilizer ◽

N2o Emissions ◽

Nitrification Inhibitors ◽

Rain Events ◽

Spring Rape

Nitrogen (N) fertilization in agricultural soils significantly contributes to the atmospheric increase of nitrous oxide (N2O). Application of nitrification inhibitors (NIs) is a promising strategy to mitigate N2O emissions and improve N use efficiency in agricultural systems. We studied the effect of 3,4-dimethylpyrazol phosphate (DMPP) as an NI on N2O mitigation from soils with spring barley and spring rape. We used both manual and automatic chamber technologies to capture the spatial and temporal dynamics of N2O emissions. Intensive manual chamber measurements were conducted two months after fertilization and fortnightly afterwards. A mini-plot experiment with different levels (0 %, 50 %, 100 %, 150 %, and 200 %) of standard N fertilizer application and 100% N with NI was also conducted for two months in soil planted with spring barley. N2O emissions were affected by the N amount and by the use of NI. Higher emissions were observed in treatments with high N levels and without NI. The effect of NI in reducing N2O emissions from spring barley plots was significant in the small chamber experiments, where NI reduced N2O emissions by 47 % in the first two months after fertilization. However, the effect of NI on N2O reduction was non-significant in the full-plot chamber experiment for the whole season. In contrast, NI significantly reduced (56 %) the seasonal N2O emissions from the soils planted with spring rape. After the initial peaks following the fertilizer application, high N2O fluxes were observed following substantial rain events. The continuous flux measurements in automated chambers showed the dynamic of N2O changes during the whole season, including some peaks that were unobservable with manual chambers because of the low temporal resolution. The concentration of nitrate was higher in the soils treated with mineral N without NI compared to soils treated with NI, which clearly showed the inhibition of the nitrification process with the application of NI. The grain and biomass yield were not affected by the use of NI. In conclusion, application of NI is an efficient mitigation technology for N2O emissions in the period following the fertilizer application, but had little effect on subsequent emissions following rain events.Keywords: nitrification inhibitors, DMPP, nitrous oxide, mitigation, agricultural soils

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Investigation into the Effects of Straw Retention and Nitrogen Reduction on CH4 and N2O Emissions from Paddy Fields in the Lower Yangtze River Region, China

Sustainability ◽

10.3390/su12041683 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1683

Author(s):

Gang Zhang ◽

Dejian Wang ◽

Yuanchun Yu

Keyword(s):

Rice Straw ◽

Yangtze River ◽

Fertilizer Application ◽

N Fertilizer ◽

N2o Emissions ◽

River Region ◽

Straw Retention ◽

Rice Season ◽

Lower Yangtze ◽

Ch4 And N2o

Straw retention is a widely used method in rice planting areas throughout China. However, the combined influences of straw retention and nitrogen (N) fertilizer application on greenhouse gas (GHG) fluxes from paddy fields merits significant attention. In this work, we conducted a field experiment in the lower Yangtze River region of China to study the effects of straw retention modes and N fertilizer rates on rice yield, methane (CH4) and nitrous oxide (N2O) emission fluxes, global warming potential (GWP), and greenhouse gas intensity (GHGI) during the rice season. The experiments included six treatments: the recommended N fertilizer—240 kg N·ha−1 with (1) no straw, (2) wheat straw, (3) rice straw, and (4) both wheat and rice straw retentions; in a yearly rice–wheat cropping system (N1, WN1, RN1, and WRN1, respectively); as well as both wheat and rice straw retentions with (5) no N fertilizer and (6) 300 kg N·ha−1 conventional N fertilizer (WRN0, WRN2). The results showed that CH4 emissions were mainly concentrated in the tillering fertilizer stage and accounted for 54.2%–87.5% of the total emissions during the rice season, and N2O emissions were primarily concentrated in the panicle fertilizer stage and accounted for 46.7%–51.4% total emissions. CH4 was responsible for 87.5%–98.5% of the total CH4 and N2O GWP during the rice season, and was the main GHG contributor in the paddy field. Although straw retention reduced N2O emissions from paddy field, it significantly increased CH4 emissions, which resulted in a significant net increase in the total GWP. Compared with the N1 treatment, the total GWP of WN1, WRN1, and RN1 increased by 3.45, 3.73, and 1.62 times, respectively; and the GHGI increased by 3.00, 2.96, and 1.52 times, respectively, so the rice straw retention mode had the smallest GWP and GHGI. Under double-season’s straw retentions, N fertilizer application increased both CH4 and N2O emissions, and the WRN1 treatment not only maintained high rice yield but also significantly reduced the GWP and GHGI by 16.5% and 30.1% (p < 0.05), respectively, relative to the WRN2 treatment. Results from this study suggest that adopting the “rice straw retention + recommended N fertilizer” mode (RN1) in the rice–wheat rotation system prevalent in the lower Yangtze River region will aid in mitigating the contribution of straw retention to the greenhouse effect.

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Effects of N top-dressing modes of panicle fertilization on soil enzymes activity and yield of rice (Oryza sativa L.)

The Journal of Agricultural Science ◽

10.1017/s0021859619000273 ◽

2019 ◽

Vol 157 (2) ◽

pp. 109-116

Author(s):

Juan Liu ◽

Jing Zhang ◽

Xiaodong Chen ◽

Yanxiu Du ◽

Junzhou Li ◽

...

Keyword(s):

Soil Enzymes ◽

Oryza Sativa L ◽

Physiological Activity ◽

Eastern China ◽

Soil Surface ◽

Grain Filling ◽

Fertilizer Application ◽

N Fertilizer ◽

Control Treatment ◽

Rice Yields

AbstractA field study to optimize the nitrogen (N) top-dressing mode of panicle fertilization and improve rice yields was conducted in mid-eastern China. Japonica cultivar Yunongjing-6 was grown and panicle N fertilizer was applied at the beginning of the inverted fourth leaf stage using three different modes: manual broadcast application (BA) on the soil surface as a control treatment, deep application during ditching at a depth of 15 cm (DD) and manual BA on the soil surface during deep ditching (BAD). The activity of soil enzymes, including invertase, urease, phosphatase and catalase, was increased significantly at the jointing, booting and grain-filling stages with the DD and BAD treatments compared with the traditional BA mode. The DD and BAD treatments also increased basal internode and neck-panicle internode bleeding intensity. The DD treatment gave the highest crop yield, increasing the yield by 0.63 and 0.31 t/hm2 in 2011 and 2012, respectively, compared with BA. The results suggest that ditching during panicle N fertilizer application after sun-drying of the fields increases rice yields, most likely by improving the activity of soil enzymes and enhancing the physiological activity of roots and grain weight.

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N2O Emissions from Two Austrian Agricultural Catchments Simulated with an N2O Submodule Developed for the SWAT Model

Atmosphere ◽

10.3390/atmos13010050 ◽

2021 ◽

Vol 13 (1) ◽

pp. 50

Author(s):

Cong Wang ◽

Christoph Schürz ◽

Ottavia Zoboli ◽

Matthias Zessner ◽

Karsten Schulz ◽

...

Keyword(s):

Assessment Tool ◽

Swat Model ◽

Fertilizer Application ◽

Measured Data ◽

N Fertilizer ◽

Organic N ◽

Percentage Error ◽

N2o Emissions ◽

Agricultural Catchments ◽

The Impact

Nitrous oxide (N2O) is a potent greenhouse gas stemming mainly from nitrogen (N)-fertilizer application. It is challenging to quantify N2O emissions from agroecosystems because of the dearth of measured data and high spatial variability of the emissions. The eco-hydrological model SWAT (Soil and Water Assessment Tool) simulates hydrological processes and N fluxes in a catchment. However, the routine for simulating N2O emissions is still missing in the SWAT model. A submodule was developed based on the outputs of the SWAT model to partition N2O from the simulated nitrification by applying a coefficient (K2) and also to isolate N2O from the simulated denitrification (N2O + N2) with a modified semi-empirical equation. The submodule was applied to quantify N2O emissions and N2O emission factors from selected crops in two agricultural catchments by using NH4NO3 fertilizer and the combination of organic N and NO3− fertilizer as N input data. The setup with the combination of organic N and NO3− fertilizer simulated lower N2O emissions than the setup with NH4NO3 fertilizer. When the water balance was simulated well (absolute percentage error <11%), the impact of N fertilizer application on the simulated N2O emissions was captured. More research to test the submodule with measured data is needed.

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Nitrogen Leaching and Nitrogen Balance under Differing Nitrogen Fertilization for Sugarcane Cultivation on a Subtropical Island

Water ◽

10.3390/w13050740 ◽

2021 ◽

Vol 13 (5) ◽

pp. 740

Author(s):

Ken Okamoto ◽

Shinkichi Goto ◽

Toshihiko Anzai ◽

Shotaro Ando

Keyword(s):

N Uptake ◽

Fertilizer Application ◽

Application Rate ◽

N Fertilizer ◽

N Leaching ◽

N Recovery ◽

N Application ◽

Fertilizer Application Rate ◽

Sugarcane Yield ◽

Cropping Seasons

Fertilizer application during sugarcane cultivation is a main source of nitrogen (N) loads to groundwater on small islands in southwestern Japan. The aim of this study was to quantify the effect of reducing the N fertilizer application rate on sugarcane yield, N leaching, and N balance. We conducted a sugarcane cultivation experiment with drainage lysimeters and different N application rates in three cropping seasons (three years). N loads were reduced by reducing the first N application rate in all cropping seasons. The sugarcane yields of the treatment to which the first N application was halved (T2 = 195 kg ha−1 N) were slightly lower than those of the conventional application (T1 = 230 kg ha−1 N) in the first and third seasons (T1 = 91 or 93 tons ha−1, T2 = 89 or 87 tons ha−1). N uptake in T1 and T2 was almost the same in seasons 1 (186–188 kg ha−1) and 3 (147–151 kg ha−1). Based on the responses of sugarcane yield and N uptake to fertilizer reduction in two of the three years, T2 is considered to represent a feasible fertilization practice for farmers. The reduction of the first N fertilizer application reduced the underground amounts of N loads (0–19 kg ha−1). However, application of 0 N in the first fertilization would lead to a substantial reduction in yield in all seasons. Reducing the amount of N in the first application (i.e., replacing T1 with T2) improved N recovery by 9.7–11.9% and reduced N leaching by 13 kg ha−1. These results suggest that halving the amount of N used in the first application can improve N fertilizer use efficiency and reduce N loss to groundwater.

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Nutrient Management Programs, Nitrogen Fertilizer Practices, and Groundwater Quality in Nebraska’s Central Platte Valley (U.S.), 1989–1998

The Scientific World JOURNAL ◽

10.1100/tsw.2001.365 ◽

2001 ◽

Vol 1 ◽

pp. 750-757 ◽

Cited By ~ 2

Author(s):

Stan Daberkow ◽

Harold Taylor ◽

Noel Gollehon ◽

Milt Moravek

Keyword(s):

Irrigation Water ◽

Fertilizer Application ◽

Management Program ◽

N Fertilizer ◽

N Availability ◽

Modest Improvement ◽

Total N ◽

Drinking Water Standard ◽

Irrigation Water Use ◽

Farmer Behavior

Given the societal concern about groundwater pollution from agricultural sources, public programs have been proposed or implemented to change farmer behavior with respect to nutrient use and management. However, few of these programs designed to change farmer behavior have been evaluated due to the lack of detailed data over an appropriate time frame. The Central Platte Natural Resources District (CPNRD) in Nebraska has identified an intensively cultivated, irrigated area with average groundwater nitrate-nitrogen (N) levels about double the EPA’s safe drinking water standard. The CPNRD implemented a joint education and regulatory N management program in the mid-1980s to reduce groundwater N. This analysis reports N use and management, yield, and groundwater nitrate trends in the CPNRD for nearly 3000 continuous-corn fields from 1989 to 1998, where producers faced limits on the timing of N fertilizer application but no limits on amounts. Groundwater nitrate levels showed modest improvement over the 10 years of this analysis, falling from the 1989–1993 average of 18.9 to 18.1 mg/l during 1994–1998. The availability of N in excess of crop needs was clearly documented by the CPNRD data and was related to optimistic yield goals, irrigation water use above expected levels, and lack of adherence to commercial fertilizer application guidelines. Over the 10-year period of this analysis, producers reported harvesting an annual average of 9729 kg/ha, 1569 kg/ha (14%) below the average yield goal. During 1989�1998, producers reported annually applying an average of 162.5 kg/ha of commercial N fertilizer, 15.7 kg/ha (10%) above the guideline level. Including the N contribution from irrigation water, the potential N contribution to the environment (total N available less estimated crop use) was estimated at 71.7 kg/ha. This is an estimate of the nitrates available for denitrification, volatilization, runoff, future soil N, and leaching to groundwater. On average, between 1989–1993 and 1994–1998, producers more closely followed CPNRD N fertilizer recommendations and increased their use of postemerge N applications � an indication of improved synchrony between N availability and crop uptake.

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DOSES AND SPLIT NITROGEN FERTILIZER APPLICATIONS ON THE PRODUCTIVITY AND QUALITY OF ARUGULA1

Revista Caatinga ◽

10.1590/1983-21252021v34n409rc ◽

2021 ◽

Vol 34 (4) ◽

pp. 824-829

Author(s):

CAMILA SENO NASCIMENTO ◽

CAROLINA SENO NASCIMENTO ◽

ARTHUR BERNARDES CECÍLIO FILHO

Keyword(s):

Nutrient Management ◽

Block Design ◽

Fertilizer Application ◽

Additional Treatment ◽

N Fertilizer ◽

Nitrate Content ◽

Management Technique ◽

Maximum Height ◽

N Losses ◽

Negative Environmental Impact

ABSTRACT Splitting nitrogen (N) fertilizer application can be an efficient nutrient management technique to improve productivity and plant quality, as well as to reduce the negative environmental impact caused by N losses. In this context, the present study investigated how the management of N affects the agronomic characteristics of field-grown arugula plants. Nine treatments were assessed in a randomized complete block design, in a 4 x 2 + 1 factorial scheme, with three replicates. The evaluated factors were doses of N (60, 120, 180 and 240 kg N ha-1), split N fertilizer applications at side-dress (two and three times) and an additional treatment without a N supply. Maximum height was obtained with the application of 198 kg N ha-1. Nitrate content, fresh mass and productivity increased with increasing N doses. There was no effect of split N fertilizer applications on the characteristics evaluated. Therefore, the supply of 240 kg N ha-1 divided into two portions was considered as the best management strategy.

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