Nitrogen Management Research Articles

Planting pattern and nitrogen management strategies: positive effect on yield and quality attributes of Triticum aestivum L. crop

Wheat (Triticum aestivum L.) is a staple food crop that plays a crucial role in global food security. A suitable planting pattern and optimum nitrogen (N) split management are efficient practices for improving wheat production. Therefore, an experiment was performed to explore the effect of N split management and sowing patterns on wheat at the Agronomy Research Farm, The University of Agriculture Peshawar, during rabi season 2020-21 and 2021-22. The treatments consisted of different nitrogen rates of 0, 80, 120, and 160 kg ha− 1 and planting patterns of W, M, broadcast and line sowing. The pooled analysis of both cropping seasons showed that application of 120 kg N ha− 1 increased spikelets spike− 1, grains spike− 1, 1000 grains weight, grain yield, grain N content, evapotranspiration and water use efficiency by 21.9, 16.7, 21.8, 70, 13, 19.9 and 40% as compared to control, respectively. In addition, W and M were observed the best management practices among all planting patterns. The M planting pattern enhanced chlorophyll a, b, carotenoids and evapotranspiration while W plating pattern improved yield components and yield of wheat as compared to broadcast planting patterns. The principal component analysis biplot showed a close association of M and W planting patterns with 120 kg N ha− 1 in most of the studied traits. Hence, it is concluded that split application of 120 kg N ha− 1 in W and M sowing patterns enhanced growth, biochemical traits and water use efficiency, reducing N fertilization from 160 to 120 kg ha− 1 while increasing grain yield of wheat. Hence, it is recommended that application of 120 kg N ha⁻¹ in combination with W and M planting patterns offer a sustainable approach to enhancing wheat production in the alkaline soil conditions of the Peshawar valley.

Substantial nitrogen abatement accompanying decarbonization suppresses terrestrial carbon sinks in China

China faces challenges in reaching its carbon neutrality goal by the year 2060 to meet the Paris Agreement and improving air quality simultaneously. Dramatic nitrogen emission reductions will be brought by this ambitious target, yet their impact on the natural ecosystem is not clear. Here, by combining two atmospheric chemistry models and two process-based terrestrial ecosystem models constrained using nationwide measurements, we show that atmospheric nitrogen deposition in China’s terrestrial land will decrease by 44–57% following two emission control scenarios including one aiming at carbon neutrality. They consequently result in a pronounced shrinkage in terrestrial net ecosystem production, by 11–20% depending on models and emission scenarios. Our results indicate that the nitrogen emission reductions accompanying decarbonization would undermine natural carbon sinks and in turn set back progress toward carbon neutrality. This unintended impact calls for great concern about the trade-offs between nitrogen management and carbon neutrality.

Free Ammonia Strategy for Nitrite-Oxidizing Bacteria (NOB) Suppression in Mainstream Nitritation Start-Up

The partial nitritation (PN)–anammox (PN/A) process offers a sustainable alternative to nitrogen management in wastewater treatment, addressing the high costs and increasing the low eco-friendliness associated with traditional nitrification/denitrification processes. Stable partial nitritation (PN) is critical for effective PN/A operation, and this study specifically focused on the need to suppress nitrite-oxidizing bacteria (NOB) to facilitate the enrichment of ammonia-oxidizing bacteria (AOB). Utilizing two sequencing batch reactors (SBRs), PN1 and PN2 with different free ammonia (FA) concentrations, this study aimed to evaluate the NOB suppression strategy while enriching AOB. The PN2 reactor, which operated with a higher initial FA concentration (50 mg/L), successfully maintained high nitritation activity, with 96.1% ammonium removal efficiency (ARE) and 95.1% nitrite accumulation efficiency (NAE) at reduced influent NH4+-N concentrations (50 mg NH4+-N/L, FA 10 mg/L). In contrast, PN1 showed inadequate NOB suppression due to lower FA concentrations (10 mg/L). These results suggest that initiating the nitritation process with higher FA concentrations can effectively suppress NOB, enhancing the stability and efficiency of PN/A processes in mainstream applications.

Residue retention and precision nitrogen management effects on soil physicochemical properties and productivity of maize-wheat-mungbean system in Indo-Gangetic Plains

Maize-based crop systems are promoted in large scale in South Asia because they are more sustainable and efficient than rice-based systems. In the present study, using two combinations of crop residue management practices (CRM) with four precision nitrogen (N) management (PNM) systems, we assessed the impacts on soil physicochemical characteristics [soil organic carbon (SOC), bulk density (BD), soil penetration resistance (PR)] and crop yields in 6 years old continuous zero tillage (ZT) practices under maize-wheat-mungbean cropping system in a sandy loam soil of northwestern India. The highest SOC (5.73 g/kg) was observed in Zero Tillage with Residue Retention (ZT + R) plots. Zero-tillage with residue retention (ZT + R) significantly reduced the bulk density over the zero-tillage with no residue retention (ZT-R) across the soil depth. The bulk density in ZT + R was 6.5 and 10.7% lower at 0–15 cm and 15–30 cm soil depth, respectively, than under ZT-R. The penetration resistance (PR) was significantly lower in ZT + R than in ZT-R across the soil depth. Soil organic carbon (SOC) in ZT + R was 7.4% higher at 0–15 cm depth and 11.9% higher at 15–30 cm depth than under ZT-R treatment. Among PNM treatments, the sequence of treatments in SOC content was 50%N + Green Seeker (GS) >33%N + GS > RDN > 70%N + GS. The system productivity (maize equivalent yield) under ZT + R in combination with 50%BN + GS was 15.0% higher than crops grown under ZT-R with RDN. The wheat equivalent yield under the ZT + R treatment is found to be higher (5.97) in the 50%BN + GS, which was 18% higher than the recommended dose of nitrogen treatment (5.04) and 28% higher than the 70%BN + GS treatment (4.68). Results demonstrated that plots with residue retention performed better, showing a 10% increase in system productivity. The study concludes that a ZT-based system with maize-based crop rotations (MWMb) with crop residue retention and precision nitrogen management can improve soil properties and system productivity in northwestern India.

Nitrogen management in wheat through nano urea

Nitrogen management in wheat through nano urea

Integrating nano-urea in nitrogen management on growth and yield of rapeseed (Brassica napus L.) under rainfed condition in North east India

Integrating nano-urea in nitrogen management on growth and yield of rapeseed (Brassica napus L.) under rainfed condition in North east India

Nitrogen management through different organic manures on growth and fruit yield of custard apple (Annona squamosa L.)

Nitrogen management through different organic manures on growth and fruit yield of custard apple (Annona squamosa L.)

Effect of different nitrogen management strategies and intercropping systems on yield and economic sustainability

Effect of different nitrogen management strategies and intercropping systems on yield and economic sustainability

Dense planting and nitrogen fertilizer management improve drip-irrigated spring maize yield and nitrogen use efficiency in Northeast China

Farmers in China often use nitrogen (N) fertilizers to ensure adequate crop growth. However, injudicious applications have increased the risk of environmental pollution, lower maize yields, and reduced profits for farmers. Appropriate N fertilizer management is crucial for improving yield and nitrogen use efficiency (NUE). This study conducted a three-year experiment involving nine N treatments (0, 45, 90, 135, 180, 225, 270, 315, and 360 kg ha-1) on a field under nitrogen fertilizer precision management (NFPM) in Northeast China. These results were compared with studies published within the past decade that analyzed yield and dry matter (DM) content under two management practices in Northeast China: conventional nitrogen fertilization management (CNFM) and water-saving fertilization management (WSFM). The findings reveal that maize yield increases with rising N application rates up to 270 kg ha-1, after which yield decreases. The kernel number (KN) and kernel weights (KW) of maize grown under NFPM were 13.7 and 14.7% higher than those grown under WSFM, respectively. Furthermore, they surpassed crops grown under CNFM by 38.4 and 21.2%, respectively. The maximum total yield of the NFPM treatment was 41.8 and 78.8% higher than WSFM and CNFM, respectively. Additionally, compared with CNFM and WSFM, NFPM significantly increased nitrogen use efficiency (NUE) across various N-level treatments. Optimizing nitrogen management could help farmers achieve higher yields and promote sustainable agricultural development.

Growth, yield, economics, and nitrogen use efficiency of transplanted rice (Oryza sativa L.) as influenced by different nitrogen management practices through neem (Azadirachta indica) coated urea

Growth, yield, economics, and nitrogen use efficiency of transplanted rice (Oryza sativa L.) as influenced by different nitrogen management practices through neem (Azadirachta indica) coated urea

Unveiling complementarities between mangrove restoration and global sustainable development goals

Indonesia, renowned as the most mangrove-rich nation, has committed to extensive mangrove restoration policies, but the effects of these policies have yet to be systematically evaluated. Our study conducts a comprehensive network analysis to investigate the synergies between mangrove restoration policy and global Sustainable Development Goals (SDGs) achievements by exploring their interactions. This investigation follows the ‘product space’ method in economics and creates the ‘Mangrove-SDG space’ to assess each metric pair's co-occurrence and comparative advantages with validated stability. Our analysis unveils a tripartite structure, encompassing socio-economic and environmental clusters, each significantly contributing to global sustainability and a distinctive mangrove cluster tied to land attributes. At the Goal level, mangrove loss showcases robust synergies with SDGs 12 (Responsible Consumption and Production) and 13 (Climate Change), and mangrove metrics such as tropical storm frequency and mangrove change, indicating strong interdependences between mangrove forests and SDGs. The result indicates that improved performance of climate change and responsible consumption can greatly enhance mangrove forests' performance in alleviating mangrove loss and reducing tropical storms. Moreover, our analysis underscores the central roles played by ‘bridge’ Goals. Indicator-level space details how they warrant prioritization because of their cascade synergistic enhancements across widely interconnected indicators, triggering systematic positive improvements. Turning to Indonesia, we advocate a strategic shift from solely expanding mangrove extent to focusing on four critical policy priorities: effective nitrogen management, enhancing Ramsar site efficiency, optimizing logistic performance, and addressing urban population conditions. These priorities are pivotal to seeking complementarities between Indonesia's international sustainability commitment and fostering mangrove restoration success.

Straw type and nitrogen-water management balance rice yield and methane emissions by regulating rhizosphere microenvironment

Context or problemStraw incorporation improves soil fertility but also poses environmental challenges due to increasing methane (CH4) emissions in paddy fields. Whether nitrogen (N) and water management can balance rice yield and CH4 emissions under different crop straw incorporation is still not well-documented. ObjectiveA three-year field experiment was conducted to probe the comprehensive effects of N application ratios and irrigation regimes on rice yield, rhizosphere soil properties, and CH4 emissions, along with the underlying mechanisms of CH4 emission variations among different straw types. MethodsA two-factor randomized block design was used with two Japonica rice cultivars as materials in 2020 and 2021. The straw incorporation treatment included no straw incorporation (NS), wheat straw incorporation (WS), and rape straw incorporation (RS). The N fertilizer application treatments included local farmers' fertilizer practice (LFP) and increasing basal fertilizer rate (IBF). Two irrigation practices, continuously-flooded irrigation (CF) and alternate wetting and drying irrigation (AWD), were designed under the WS and RS treatments in 2022. Results1) WS-IBF and RS-IBF enhanced yield by 6.70∼9.03 % and 8.13∼9.50 % compared to WS-LFP and RS-LFP, respectively. AWD further increased yield by 6.28∼7.76 % compared to CF. 2) WS-IBF and RS-IBF enhanced dissolved organic carbon (DOC) content, synchronously boosted the methanogens (mcrA) and methanotrophs (pmoA) abundances, but decreased the pmoA/mcrA ratio, which significantly promoted CH4 emission flux in early growth stage. This resulted in a 5.04∼8.01 % and 4.60∼7.88 % increase in CH4 emissions compared to WS-LFP and RS-LFP, respectively, but a decrease in yield-scaled CH4 emissions. AWD reduced DOC content, facilitated the conversion of ammonium N to nitrate N, increased dissolved oxygen content, and hence decreased CH4 emissions by 23.41∼24.38 % compared to CF. 3) RS significantly increased microbial biomass C, N, and related metabolites, leading to a 1.29∼2.73 % increase in yield compared to WS. Meanwhile, RS promoted Nitrospira abundance as well as pterin and flavonoid metabolites associated with mcrA inhibition, while decreasing Anaeromyxobacter abundance, ammonium N, and DOC content, resulting in an increase in the pmoA/mcrA ratio and a noticeable drop in CH4 emissions compared to WS. ConclusionsRS combined with IBF and AWD is a more sustainable integrated practice in light of the synergistic improvement in rice production and environmental benefits. ImplicationsThe results reveal that optimizing N and water management can synergize high-yield and low-carbon by regulating rhizosphere microenvironment in rice production under crop straw incorporation.

Tracing nitrogen sources and transformation characteristics in a large basin with spatially heterogeneous pollution distribution

This study used dual stable isotopes to examine nitrate sources and geographical distribution in the Liao River Basin (LRB), one of China's seven major river basins. During a normal hydrological season in April 2021, water samples were taken from the main streams of the Liao River (MLR), Shuangtaizi River (STR), Hun River (HR), Taizi River (TZR), and Daliao River (DLR). Monitoring results indicated that 93% of the water samples had a total nitrogen level exceeding the Class IV limit (1.5 mg/L) of the ‘Environmental Quality Standards (EQS) for surface water’, indicating a serious nitrogen pollution status. 71.3% of the total nitrogen on average was in the form of nitrate. The scatterplots of δD-H2O and δ18O-H2O showed that water in TZR and DLR were mainly affected by precipitation, while MLR, STR and HR were additionally impacted by evaporation and groundwater. The overall δ15N and δ18O of NO3− varied from 7.7‰ to 17.9‰ and 0.6‰–11.2‰, respectively. The correlations between δ15N-NO3- and δ18O-NO3-, along with attribution results from the Bayesian isotopic mixing model, indicated a predominant role of manure/sewage (MS) pollution in affecting river nitrate, accounting for 78% of total nitrate in MLR and 72% in DLR. A positive correlation between δ15N-NO3- and δ18O-NO3- in MLR indicated the occurrence of denitrification process. Overall, attribution results showed that the primary nitrate sources varied in different river systems within such a large basin, mainly due to spatially varied land use and human activities. Tailored nitrogen management strategies should be implemented to address the main anthropogenic pressures.

Modeling Tomato Yield and Quality Responses to Water and Nitrogen Deficits with a Modified Crop Water Production Function

Increasingly severe crises, such as climate change, water scarcity and environmental pollution, pose significant challenges to global food security and sustainable agricultural development. For efficient and sustainable tomato cultivation management under resource constraints, quantitatively describing the relationship between yield-quality harvest and water-nitrogen application is practically beneficial. Two successive greenhouse experiments with three irrigation levels (1/3 FI, 2/3 FI, and full irrigation (FI)) and four nitrogen fertilizer treatments (0 FN, 1/3 FN, 2/3 FN, and full nitrogen (FN)) were conducted on tomatoes during the whole phenological stage. The tomato evapotranspiration and nitrogen application amount, yield, comprehensive quality, solid–acid ratio, and lycopene content were measured. Based on crop water production functions, three equation forms of water-nitrogen production functions containing 20 models were established and evaluated to predict tomato harvest parameters. The results show that water increased tomato yield while decreasing fruit quality, and the effect of nitrogen was primarily contrary. Water most significantly impacted tomato formation, and the interaction of water and nitrogen changed among different harvest parameters. Tomato yield and quality formation was more sensitive to water and nitrogen at the flowering and fruit maturation stages. Model Singh-2 outweighed other models for yield estimates, with an R2 of 0.71 and an RMSE of 0.11. Singh-Log, Singh-sigmoid and Rao-Root models were effective models for comprehensive quality, solid–acid ratio, and lycopene content prediction, with an R2 of 0.41, 0.62, and 0.42, and an RMSE of 0.33, 0.50, and 0.16, respectively. Finally, models in the form of f(ETi)·f(N) were ideal for tomato harvest prevision and are recommended for water and nitrogen management in tomato cultivation.

Nitrogen Uptake and Use Efficiency of Aerobic Rice as Affected by Different Nitrogen Management: A Review

Nitrogen Uptake and Use Efficiency of Aerobic Rice as Affected by Different Nitrogen Management: A Review

Principles and Significance of Nitrogen Management for Blackberry Production

Blackberry cultivation presents significant opportunities for fruit growers in subtropical regions, where nitrogen (N) is identified as a crucial macronutrient for optimal production. Given the variability in climate and soil conditions, determining the ideal N fertilizer amount can be complex. Effective blackberry cultivation requires careful attention to the principles of nutrient stewardship, including the selection of appropriate N sources, application rates, timing, and placement. Recommended N rates generally range from 25–45 kg/ha in the first year and 45–70 kg/ha in subsequent years, with adjustments based on plant type and regional conditions. The choice of fertilizer, particularly NH4+, is beneficial for blackberry plants, which thrive in acidic soils and show improved biomass and chlorophyll levels with this form of N. Research on N-cycling reveals its importance in supporting new plant growth, such as primocane development. However, improper N management, either excessive or insufficient, can negatively impact flower bud production and, consequently, fruit setting and yield. By using databases such as Google Scholar, Scopus, and Web of Science, this review synthesizes existing research on the role of N in blackberry cultivation, emphasizing the importance of precise fertilization practices tailored to regional climate and soil conditions. By highlighting variations in recommended N amounts and underscoring the principles of nutrient stewardship, this review aims to guide growers in achieving sustainable and high-quality blackberry production.

Paradox of lake nitrogen concentration change response to watershed management: Case study of China

Human activities have caused rapid increases in lake nutrient loads over the past few decades, resulting in severe eutrophication. To mitigate eutrophication in lakes, watershed management is conducted worldwide. After decades of watershed environmental management practices, some lakes have significantly improved in water quality, whereas others continue to deteriorate. Differentiations in watershed environmental management practices have been a conundrum for watershed managers for many years. This study analyzed over 20 years of nitrogen concentration data from 13 different types of lakes in China, exploring the driving forces behind water quality changes. The results showed that agricultural nitrogen management has emerged as a predominant driver of lake nitrogen concentration changes, with the impacts of climatic factors diminishing post-transition. Two obstacles hinder the achievement of water quality goals: time lags and climate change. The time lag between agricultural management measures and water quality improvements maybe decades. Meanwhile, climate change, especially extreme weather events, introduces uncertainties that may trigger short-term deterioration. Despite the uncertainty surrounding lake nitrogen concentration changes, lakes with advanced governance structures still exhibited greater resilience to climatic changes compared to those in the early stages of environmental management. To improve water quality, more efforts and patience are required.

Radiation synthesis of sodium alginate/gelatin based ultra-absorbent hydrogel for efficient water and nitrogen management in wheat under drought stress

The main focus of this study was on using radiation to make an ultra-absorbent hydrogel (UAH) from sodium alginate (SA) and gelatin (GL) biopolymers. This UAH can effectively handle water and nitrogen in wheat farming during drought stress. The hydrogel was synthesized by gamma irradiation-induced SA/GL/polyacrylamide crosslinking at 10–40 kGy. Varying SA/GL ratios affected swelling and the gel fraction of SA/GL/PAm hydrogels. The (SA/GL 17/83) hydrogel exhibited a 40.03 g/g swelling degree, while increasing SA content resulted in higher swelling, peaking at 75.5 g/g for (SA/GL 83/17). This indicated a synergistic interaction between SA and GL. The gel fraction also increased from 76.8 to 90.3%, with a higher GL content reflecting increased crosslinking. After multiple hydrolysis cycles, the hydrogel achieved 1293 (g/g) swelling and 36 days of water retention. When applied to wheat (Triticuma estivum) under drought stress, it significantly improved shoot length (18%), root length (43%), shoot fresh weight (49%), and shoot dry weight (51%) under extreme drought. The significant increases in protein and carbohydrate content in both shoots (up to 32% and 19%, respectively) and grains (up to 21% and 24%, respectively), along with the reduction in proline content (up to 38%), demonstrate that ultra-absorbent hydrogel (UAH) effectively enhances nitrogen content, photosynthesis, and overall plant health in wheat under varying drought stress levels. This novel SA/GL-based UAH holds promise for addressing water scarcity and agricultural challenges, offering a sustainable solution for water and nitrogen management under drought stress.

Optimizing Maize Productivity and Soil Fertility: Insights from Tillage, Nitrogen Management, and Hydrochar Applications

Optimizing Maize Productivity and Soil Fertility: Insights from Tillage, Nitrogen Management, and Hydrochar Applications

Optimal nitrogen management for high yield and N use efficiency of ratoon sorghum

Sorghum ratooning, a time and labor-saving cultivation practice, is increasingly being adopted by farmers in Southwest China as an alternative. Efficient N fertilizer management is critical for economical production of sorghum and the long-term protection of the environment. To investigate the impact of N management on grain yield and nitrogen use efficiencies (NUEs) of ratoon sorghum system, a three-year field experiment was conducted for Jinyunuo3 (a hybrid cultivar) and Guojiaohong1 (an inbred cultivar) using 12 combinations of N rates and splitting ratios. The results showed that increasing N rate and splitting application times led to improvements in various growth parameters such as dry matter weight, crop growth rate (CGR), leaf area index (LAI), and photosynthetic potential (PP). The main, ratoon, and annual yields increased with N rate increase, but there was no significant difference between 225 and 150 kg N ha−1 in the ratoon and annual yields. Splitting the application of N fertilizer enhanced grain yield compared to a single dose application method, especially three-split applications yielded higher than two-split applications. Compared with N rates of 225 and 150 kg ha−1, N rate of 75 kg ha−1 increased apparent recovery rate of applied nitrogen (REN), agronomic efficiency of applied nitrogen (AEN), and partial factor productivity from applied nitrogen (PFPN) in both main season and whole year. But through splitting application methods at high N rates could achieve similar or even higher levels of NUEs compared to all applied as basal fertilizer at low N rates. Therefore, it could be recommended that applying 150 kg N ha−1 with a basal-jointing-heading fertilizer ratio of 2:4:4 represented an efficient N management practice to synchronously obtain high grain yield and NUEs in ratoon sorghum system in Southwest China.