Nitrogen Contents in Soil, Grains, and Straw of Hybrid Rice Differ When Applied with Different Organic Nitrogen Sources

In the rice–wheat (R–W) system, inorganic nitrogen (N) fertilizer (urea, etc.) is the largest component of the N cycle, because the supply of N from organic fertilizers is insufficient. But the 4% Initiative aims to improve organic matter and stimulate carbon sequestration in soils using best agronomic practices (sustainable management practices) which are economically, environmentally, and socially friendly. This research project was, therefore, designed to assess the impact of various organic sources (OS, animal manure versus plant residues), inorganic N (urea), and their different combinations on the N concentrations in soils and plants (i.e., grains and straw) of hybrid rice plants. The experiments were conducted on farmers’ fields in Batkhela (Malakand), northwestern Pakistan, over 2 years (2011–2012 (Y1) and 2012–2013 (Y2)). The results revealed that N concentrations in soil as well as in rice plants ranked first when applied with urea-N, followed by the application of N in mixture (urea + OS), while the control plots (no N applied) ranked at the bottom. Among the six OS (three animal manures: poultry, sheep, and cattle; and three crop residues: onion, berseem, and wheat), application of N in the form of poultry manure was superior in terms of higher N concentrations in both soil and plants. Applying the required total N (120 kg N ha−1) in the form of 75% N from urea +25% N from OS resulted in higher N concentrations in soil and plants in Y1. The required total N (120 kg N ha−1) application in the form of 50% N from urea +50% N from OS produced higher N concentrations in soil and plants in Y2. It was concluded from the results, that combined application of N sources in the form of urea + OS can produce good performances in terms of higher N concentrations in soil as well as in rice plants under the R–W system. Integrated use of urea (N-fertilizer) with organic carbon sources (animal manures and crop residue) could sustain rice-based (exhaustive) cropping system.

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Effect of Nitrogen Fertilizer on Soil CO2 Emission Depends on Crop Rotation Strategy

Sustainability ◽

10.3390/su12135271 ◽

2020 ◽

Vol 12 (13) ◽

pp. 5271

Author(s):

Dejie Kong ◽

Nana Liu ◽

Chengjie Ren ◽

Huiying Li ◽

Weiyu Wang ◽

...

Keyword(s):

Crop Rotation ◽

Co2 Emission ◽

Management Practices ◽

N Fertilizer ◽

Emission Rates ◽

Fertilizer Management ◽

Soil Co2 ◽

Soil Co2 Emission ◽

The Impact ◽

Rotation Strategy

Developing environmentally friendly and sustainable nitrogen (N) fertilizer management strategies is crucial in mitigating carbon dioxide (CO2) emission from soil. How N fertilizer management practices influence soil CO2 emission rates under different crop rotations remains unclear. The aim of this study was to assess the impact on soil CO2 emission and soil physicochemical properties of three N fertilizer treatments including traditional rate (TF), optimized rate (0.8TF), and no fertilizer (NF) under three different crop rotation treatments: wheat-fallow (WF), wheat-soybean (WS), and wheat-maize (WM) over two years in a field experiment in northwest China. The rates were 5.51, 5.60, and 5.97 μmol·m−2·s−1 of mean soil CO2 emission under the TF, 0.8TF, and NF treatments, respectively. Mean soil CO2 emission rates were 21.33 and 26.99% higher under the WM rotation compared with the WF and WS rotations, respectively. The WS rotation showed higher soil nutrient content and lower soil CO2 emissions, and reduced fertilizer application. Importantly, soil organic carbon (SOC) concentration in the topsoil can be maximized by including either a summer legume or a summer maize crop in winter wheat rotations, and by applying N fertilizer at the optimal rate. This may be particularly beneficial in the dryland cropping systems of northern China.

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N2O Fluxes and Related Processes of Denitrification in Acidified Soil

10.21203/rs.3.rs-136928/v1 ◽

2020 ◽

Author(s):

Qian Zheng ◽

Junjun Ding ◽

Qiaozhen Li ◽

Chunying Xu ◽

Wei Lin ◽

...

Keyword(s):

Soil Ph ◽

Irrigation Water ◽

Soil Acidification ◽

N Fertilizer ◽

Soil Conditions ◽

Natural Soil ◽

Large Contribution ◽

Total N ◽

Mapping Approach ◽

The Impact

Abstract In North China, high levels of N fertilizer and irrigation water are used in fields, which cause considerable N2O fluxes via several pathways, especially anaerobic denitrification. Anaerobic denitrification is regarded as an important microbial process for N2O production in soils with a low O2 level and high N and labile C availability (the typical soil conditions caused by high levels of N fertilizer and irrigation water in the field). We conducted an anaerobic incubation experiment to determine the impact of soil acidification (with a series of soil pH levels, pH 6.2, pH 7.1, and pH 8.7) on N2O source partitioning with the addition of KNO3 and glucose. Natural abundance isotope techniques and gas inhibitor technique were applied to analyze the N2O flux derived from fungal denitrification and bacterial denitrification and its isotopocule characteristics emitted from soils after the addition of NO- 3 and glucose. A mapping approach was used to obtain further insight into the N2O production processes. Our findings confirmed that soil pH strongly controlled the N2O production and reduction rates of denitrification. Soil acidification significantly increased N2O emissions varied from 0.76 mg N kg-1 for natural soil (pH 8.7), to 1.88 mg N kg-1 for pH 7.1, and to 2.35 mg N kg-1 for pH 6.2, and had a blockage effect on the reduction of N2O to N2. The addition of carbon sources promoted complete denitrification. We assumed a higher contribution of fungal denitrification to N2O production compared to total N2O emission associated with acidified soil. A promotion of the contribution of fungal denitrification-derived N2O was indeed observed with decreasing pH, increasing from 0.28 mg N kg-1 for pH 8.7 to 0.94 mg N kg-1 for pH 6.2. The addition of glucose further increased the contribution of fungal denitrification to N2O production from 0.99 mg N kg-1 for pH 8.7 to 3.66 mg N kg-1 for pH 6.2. The mapping approach provided rational results for correcting N2O reduction compared with the acetylene inhibition method. The results calculated by both methods indicated a reasonably large contribution of fungal denitrification to total N2O production in acidified soils.

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Quantification of Key Genes Steering the Microbial Nitrogen Cycle in the Rhizosphere of Sorghum Cultivars in Tropical Agroecosystems

Applied and Environmental Microbiology ◽

10.1128/aem.02917-08 ◽

2009 ◽

Vol 75 (15) ◽

pp. 4993-5000 ◽

Cited By ~ 101

Author(s):

Brigitte Hai ◽

Ndeye Hélène Diallo ◽

Saidou Sall ◽

Felix Haesler ◽

Kristina Schauss ◽

...

Keyword(s):

Microbial Communities ◽

Nitrogen Cycle ◽

Plant Development ◽

Water Availability ◽

Management Practices ◽

Ammonia Oxidation ◽

Organic Fertilizers ◽

Ammonia Oxidizing Bacteria ◽

Development Stages ◽

The Impact

ABSTRACT The effect of agricultural management practices on geochemical cycles in moderate ecosystems is by far better understood than in semiarid regions, where fertilizer availability and climatic conditions are less favorable. We studied the impact of different fertilizer regimens in an agricultural long-term observatory in Burkina Faso at three different plant development stages (early leaf development, flowering, and senescence) of sorghum cultivars. Using real-time PCR, we investigated functional microbial communities involved in key processes of the nitrogen cycle (nitrogen fixation, ammonia oxidation, and denitrification) in the rhizosphere. The results indicate that fertilizer treatments and plant development stages combined with environmental factors affected the abundance of the targeted functional genes in the rhizosphere. While nitrogen-fixing populations dominated the investigated communities when organic fertilizers (manure and straw) were applied, their numbers were comparatively reduced in urea-treated plots. In contrast, ammonia-oxidizing bacteria (AOB) increased not only in absolute numbers but also in relation to the other bacterial groups investigated in the urea-amended plots. Ammonia-oxidizing archaea exhibited higher numbers compared to AOB independent of fertilizer application. Similarly, denitrifiers were also more abundant in the urea-treated plots. Our data imply as well that, more than in moderate regions, water availability might shape microbial communities in the rhizosphere, since low gene abundance data were obtained for all tested genes at the flowering stage, when water availability was very limited.

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Growth and Productivity Response of Hybrid Rice to Application of Animal Manures, Plant Residues and Phosphorus

Frontiers in Plant Science ◽

10.3389/fpls.2016.01440 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 11

Author(s):

Amanullah ◽

Shams-ul-Tamraiz Khan ◽

Asif Iqbal ◽

Shah Fahad

Keyword(s):

Hybrid Rice ◽

Plant Residues ◽

Animal Manures

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Combined effects of nutrient enrichment and inorganic sedimentation on benthic biota in an experimental stream system

Water Quality Research Journal ◽

10.2166/wqrj.2017.038 ◽

2015 ◽

Vol 52 (3) ◽

pp. 151-165 ◽

Cited By ~ 2

Author(s):

Justin W. Chase ◽

Glenn A. Benoy ◽

Joseph M. Culp

Keyword(s):

Nutrient Enrichment ◽

Management Practices ◽

Nutrient Loading ◽

Habitat Degradation ◽

Inorganic Nitrogen ◽

Ecosystem Integrity ◽

Macroinvertebrate Assemblages ◽

Nitrogen Concentrations ◽

Fluvial Ecosystem ◽

The Impact

Sedimentation and nutrient loading are among the most prevalent threats to fluvial ecosystem integrity. This study employed artificial streams (mesocosms) to simulate individual and combined impacts of nutrient enrichment and deposited fine sediment on benthic biota. Ninety-six circular mesocosms were used in a 21-day crossed experiment that measured the impact of three substrate compositions (0, 25, and 50% fines <2 mm) and four nitrogen concentrations (17, 22, 43, and 94 μg L–1 (soluble inorganic nitrogen)) on periphyton and benthic macroinvertebrate assemblages. Permutational multivariate analysis of variance (PERMANOVA) of macroinvertebrate assemblages indicated substantial shifts in structural composition, while univariate models for Lepidostomatidae and total Ephemeroptera, Plecoptera and Trichoptera revealed that nutrient and sediment subsidies related to single factors were suppressed by an additional stressor. Stressor mechanism overlap was evident at higher treatment levels, as moderate nutrient enrichment increased nutritional resources but high nitrogen concentrations lead to substrate smothering by periphyton, contributing to habitat degradation originating from inorganic sedimentation. Our study is consistent with research showing that nutrient loading and sedimentation interact to deteriorate lotic systems beyond levels attributable to either individual stressor. Management practices and pollution standards need to incorporate relationships between stressors tightly co-vary in natural settings.

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Organic and inorganic nitrogen leaching from incubated soils subjected to freeze-thaw and flooding conditions

Canadian Journal of Soil Science ◽

10.4141/cjss94-028 ◽

1994 ◽

Vol 74 (2) ◽

pp. 201-206 ◽

Cited By ~ 17

Author(s):

F. L. Wang ◽

J. R. Bettany

Keyword(s):

Inorganic Nitrogen ◽

Sharp Decrease ◽

Nitrogen Leaching ◽

Water Soluble ◽

Organic N ◽

Total N ◽

Freeze Thaw ◽

Ammonium N ◽

Nitrate And Nitrite ◽

The Impact

Freeze-thaw and flooding of usually well-drained soils occur in the spring in the prairie and boreal regions of Canada. We studied the impact of these conditions on nitrogen leaching in a Black Chernozemic soil (Udic Boroll). Soil samples, subjected to different treatments, were incubated for 12 wk in the laboratory and leached every 2 wk with 0.001 M CaCl2 solution. The cumulative leaching loss of total N (mg kg−1 soil) was reduced by freeze-thaw (76.0), flooding (41.4) and a superimposition of the two treatments (28.8) compared to the control (109). All treatments affected the distribution of the forms of N leached. The total loss of water soluble organic N (SON) and ammonium-N was in the order of flooded > flooded-freeze-thaw > freeze-thaw = control. In the leachates from the flooded treatments, SON accounted for 71.5–77.4% of the total N leached. Nitrate- and nitrite-N dominated the total leachable N in the unflooded treatments following an order of control > freeze-thaw > flooded = flooded-freeze-thaw. During the incubation, the Eh of the flooded soils decreased from 344 to −46 mV, compared to a variation in Eh from 355 to 301 mV for the unflooded soils. The maximum rate of leaching of organic nitrogen from the flooded treatment (0.53 mg N kg−1 d−1) coincided with a sharp decrease in Eh, from 131 to 42 mV. It is concluded that climatic events will have a significant impact on the dynamics of soil nitrogen. Flooding, in particular, may promote the loss of N in water soluble organic matter. Key words: Flooding, freeze-thaw, organic and inorganic nitrogen leaching, redox potential

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N2 fixation by soybeans grown with different levels of mineral nitrogen, and the fertilizer replacement value for a following crop

Canadian Journal of Soil Science ◽

10.4141/s01-003 ◽

2002 ◽

Vol 82 (2) ◽

pp. 139-145 ◽

Cited By ~ 16

Author(s):

M. J. Goss ◽

A. de Varennes ◽

P. S. Smith ◽

J. A. Ferguson

Keyword(s):

Response Curve ◽

C:N Ratio ◽

N Fertilizer ◽

Fertilizer N ◽

Mineral N ◽

Total N ◽

Fertilizer Recommendations ◽

Second Year ◽

The Impact ◽

Different Levels

A field experiment was established to study the impact of added mineral N on the prediction of N2 fixation by soybean, and the consequences for the nature of any N credit that might be used to modify fertilizer recommendations to a following non-fixing crop. Nodulating and non-nodulating isolin es of soybean were grown with five rates of N fertilizer, and in a second year corn was grown in the same plots and its yield compared with a response curve. Yield, total N content, amount of N derived from soil, and fertilizer utilization of the nodulating isoline of soybean were not affected by fertilizer N. In contrast, mineral N inhibited nodulation and led to a decrease in the amount of N fixed. The balance of N in the soil was more negative for lower levels of applied N, but by the following spring the amount of mineral N in the soil was the same in all plots. The yield of corn was greater in the plots that had grown nodulating soybean than the non-nodulating isoline. The N fertilizer replacement value of 25 (8 kg N ha-1 resulted from a greater amount of root residues in the nodulating soybean, together with a C:N ratio that would favour faster mineralization than in the non-nodulating isoline. Key words: Corn, mineral N, N credit, fixation, soybean

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Application of Corn Straw and Woody Peat to Improve the Absorption and Utilization of 15N-Urea by Maize

Sustainability ◽

10.3390/su14020820 ◽

2022 ◽

Vol 14 (2) ◽

pp. 820

Author(s):

Chenming Lin ◽

Sen Dou ◽

Mahmoud Gamal Mohamed Abd El-Rahim ◽

Xin Liu ◽

Dong Wu ◽

...

Keyword(s):

Nitrogen Fertilizer ◽

Soil Layer ◽

N Fertilizer ◽

Utilization Efficiency ◽

Organic Fertilizers ◽

15N Tracer ◽

Corn Straw ◽

Fertilizer Use ◽

15N Urea ◽

The Impact

Increasing nitrogen fertilizer use efficiency has become an environmental and economic demand in order to minimize losses of nitrogen and maximize the output from nitrogen added. The application of organic amendments with N fertilizers could be proposed as an important economic and environmental practice for improving N fertilizer use. A two-year field experiment was carried out using the 15N tracer technique to study the impact of corn straw and woody peat application on uptake and utilization of N fertilizer by maize plant. Three treatments were set up: CK (15N labeled urea alone), CS (15N labeled urea + crushed corn straw) and WP (15N labeled urea+ crushed woody peat). The results showed that, as compared to CK, both straw and peat treatments led to (i) an increase in yield of maize, 15N urea utilization rate, and residual 15N urea remained in soil by 11.20% and 19.47%, 18.62% and 58.99%, 41.77% and 59.45%, respectively, but (ii) a decrease in the total loss rate by 6.21% and 16.83% (p < 0.05), respectively over the two seasons. Moreover, the significantly highest effect was recorded with woody peat application rather than that with corn straw. Our study suggests that corn straw and woody peat can be used as organic fertilizers to increase maize yields, promote nitrogen fertilizer balance sheet, reduce the leaching of N fertilizer into the subsurface soil layer, and facilitate the further absorption and utilization of soil residual nitrogen. Therefore, the application of humified organic material play a crucial role in N utilization efficiency enhancement.

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Estimating Nitrogen Flows and Nitrogen Footprint for Agro-Food System of Rwanda Over the Last Five Decades: Challenges and Measures

Frontiers in Environmental Science ◽

10.3389/fenvs.2021.778699 ◽

2021 ◽

Vol 9 ◽

Author(s):

Barthelemy Harerimana ◽

Minghua Zhou ◽

Muhammad Shaaban ◽

Bo Zhu

Keyword(s):

Food Insecurity ◽

Management Practices ◽

Food System ◽

Crop Yields ◽

N Uptake ◽

N Fertilizer ◽

Soil N ◽

N Losses ◽

Total N ◽

Per Capita

This study presents the first detailed estimate of Rwanda’s nitrogen (N) flows and N footprint for food (NFfood) from 1961 to 2018. Low N fertilizer inputs, substandard production techniques, and inefficient agricultural management practices are focal causes of low crop yields, environmental pollution, and food insecurity. We therefore assessed the N budget, N use efficiency (NUE), virtual N factors (VNFs), soil N mining factors (SNMFs), and N footprint for the agro-food systems of Rwanda with consideration of scenarios of fertilized and unfertilized farms. The total N input to croplands increased from 14.6 kg N ha−1 yr−1 (1960s) to 34.1 kg N ha−1 yr−1 (2010–2018), while the total crop N uptake increased from 18 kg N ha−1yr−1 (1960s) to 28.2 kg N ha−1yr−1 (2010–2018), reflecting a decline of NUE from 124% (1960s) to 85% (2010–2018). Gaseous N losses of NH3, N2O, and NO increased from 0.45 (NH3), 0.03 (N2O), and 0.00 (NO) Gg N yr−1 (1960s) to 6.98 (NH3), 0.58 (N2O), and 0.10 (NO) Gg N yr−1 (2010–2018). Due to the low N inputs, SNMFs were in the range of 0.00 and 2.99 and the rice production, cash-crop production, and livestock production systems have greater SNMFs in Rwanda. The weighted NFfood per capita that presents the actual situation of fertilized and unfertilized croplands increased from 4.0 kg N cap−1 yr−1 (1960s) to 6.3 kg N cap−1 yr−1 (2010–2018). The NFfood per capita would increase from 3.5 kg N cap−1 yr−1 to 4.8 kg N cap−1 yr−1 under a scenario of all croplands without N fertilizer application and increase from 6.0 to 8.7 kg N cap−1 yr−1 under the situation of all croplands receiving N fertilizer. The per capita agro-food production accounted for approximately 58% of the national NFfood. The present study indicates that Rwanda is currently suffering from low N inputs, high soil N depletion, food insecurity, and environmental N losses. Therefore, suggesting that the implementation of N management policies of increasing agricultural N inputs and rehabilitating the degraded soils with organic amendments of human and animal waste needs to be carefully considered in Rwanda.

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Leaf-to-fruit ratio affects the impact of foliar-applied nitrogen on N accumulation in the grape must

OENO One ◽

10.20870/oeno-one.2016.50.1.55 ◽

2016 ◽

Vol 50 (1) ◽

pp. 23 ◽

Cited By ~ 2

Author(s):

Thibaut Verdenal ◽

Jorge E. Spangenberg ◽

Vivian Zufferey ◽

Fabrice Lorenzini ◽

Agnes Dienes-Nagy ◽

...

Keyword(s):

Leaf Area ◽

Management Practices ◽

Canopy Height ◽

N Recovery ◽

Total N ◽

Foliar N ◽

N Concentration ◽

N Partitioning ◽

The Impact ◽

Foliar Urea

Aims: Agroscope investigated the impact of the leaf-to-fruit ratio on nitrogen (N) partitioning in grapevine following a foliar urea application with the aim of increasing the yeast assimilable nitrogen (YAN) concentration in the must. Methods and results: Foliar urea was applied to field-grown Vitis vinifera L. cv. Chasselas grapevines as part of a split-plot trial with two variable parameters: canopy height (90 or 150 cm) and fruit load (5 or 10 clusters per vine). Foliar application of 20 kg/ha of 15N-labelled urea (10 atom% 15N) was performed at veraison. The isotope labelling method allowed to observe foliar-N partitioning in the plant at harvest. The leaf-to-fruit ratio varied between 0.4 and 1.6 m2/kg, and strongly impacted the N partitioning in the grapevines. Total N and foliar-N partitioning was mainly affected by the variation of canopy height. The YAN concentration varied from 143 to 230 mg/L (+60 %) depending on the leaf area. An oversized canopy (+31 %DW) induced a decrease in the total N concentration of all organs (-17 %), and a decrease in YAN quantity in the must in particular (-53 %). A negative correlation between the N concentration and the carbon isotope discrimination (CID) could be pointed out in a condition of no water restriction (e.g., R2 = 0.65 in the must).Conclusion: An excessive leaf area can induce YAN deficiency in the must. Thus, a balanced leaf-to-fruit ratio – between 1 and 1.2 m2/kg – should be maintained to guarantee grape maturity, YAN accumulation in the must and N recovery in the reserve organs. Significance and impact of the study: The results of this study encourage further research to understand the role of other physiological parameters that affect N partitioning in the grapevine – YAN accumulation in the must in particular – and add new perspectives for N management practices in the vineyard.

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