1、Comparison of yield and nitrogen use efficiency of different types of nitrogen fertilizers for different rice cropping systems under subtropical monsoon

Controlled release urea (CRU) and urea with nitrification inhibitor could improve yields and nitrogen use efficiency (NUE) in a number of production systems. However, their effectiveness will be strongly influenced by environmental conditions.

2、Nitrogen transformations in modern agriculture and the role of biological nitrification inhibition

We examine key recent discoveries in the emerging field of BNI research, focusing on BNI compounds and their specificity and transport, and discuss prospects for their role in improving agriculture...

3、Effects of fertilizer type and rate on summer maize grain yield and ammonia volatilization loss in northern China

In this study, we analyzed the effects of different maize varieties with nitrogen utilization efficiency, fertilizer type, and rate on the ammonia volatilization emission of farmland. Aimed to seek the best matching method to improve grain yield and fertilizer utilization efficiency of summer maize simultaneously.

4、Synthesis of a slow‐release and superabsorbent nitrogen fertilizer and its properties

A slow-release and superabsorbent nitrogen fertilizer (SSNF) was synthesized by aqueous solution copolymerization of acrylic acid and maleic anhydride using N, N ′-methylene bisacrylamide as a crosslinker, ammonium persulfate and sodium sulfite as an initiator in the presence of urea.

Effects of slow or controlled release fertilizer types and fertilization modes on yield and quality of rice

Introduction Nitrogen (N) is an essential nutrient for all plants, and the application of N fertilizer plays an important role in rice (Oryza sativa L.) yield and quality (Ding et al. 2014; Jiang et al. 2016).

The distribution of functional N

Understanding the dynamics of N transformation and movement in soils is complex because of the large number of variables affecting this process [14, 15, 30 – 33]. Nitrogen fertilization and the type of N fertilizers have also been reported to affect N-related microbial populations [34].

Effects of Different Fertilizer and Irrigation Water Types, and Dissolved Organic Matter on Soil C and N Mineralization in Crop Rotation Farmland

Abstract Inorganic N fertilizer and irrigation water types on the C and N dynamics are poorly understood. This work aimed to evaluate the effect of different N fertilizer and irrigation water types on soil C and N mineralization.

The Contributions of Cultivar and Fertilization Improvements to Single Rice Nitrogen Use Efficiency Trends Across China

Nitrogen use efficiency (NUE) serves as a useful performance indicator to benchmark agricultural nitrogen management. It is determined by genotype-environment-management interaction, making the quantification of the key drivers and the mechanism behind spatiotemporal trends of NUE challenging. In th …

The effects of nitrogen fertilization on N2O emissions from a rubber plantation

To gain the effects of N fertilizer applications on N2O emissions and local climate change in fertilized rubber (Hevea brasiliensis) plantations in the tropics, we measured N2O fluxes from ...

Regional distribution of nitrogen fertilizer use and N‐saving potential for improvement of food production and nitrogen use efficiency in China

BACKGROUND: An apparently large disparity still exists between developed and developing countries in historical trends of the amounts of nitrogen (N) fertilizers consumed, and the same situation hold...

标题：Types and Properties of Nitrogen Fertilizers

Nitrogen fertilizers are indispensable in agricultural production. They mainly promote plant growth and development by providing nitrogen nutrition required for plant growth. There are various types and properties of nitrogen fertilizers, which can be classified according to their source, form, and effect. The following introduces several common types and their properties.

1. Urea (Carbamide)

   • Chemical composition: The chemical name of urea is ammonium bicarbonate, with the molecular formula C4H8O12N, where N represents the content of the nitrogen element.
   • Physical properties: Urea is a white or slightly yellow crystalline powder, having hygroscopicity and caking property. Its melting point is about 132°C, and its boiling point is about 627°C.
   • Thermal stability: Urea will decompose into ammonia gas, carbon dioxide, and water when heated. it should not be stored or used at high temperatures.
   • Chemical properties: Urea has high solubility in water but reacts with acid to generate ammonia gas. Under alkaline conditions, urea undergoes hydrolysis.
   • Applications: Urea is mainly used to manufacture nitrogen fertilizers, nitrides, and other chemical products. It also serves as a nitrogen source for agricultural fertilization.

2. Ammonium Nitrate

   • Chemical composition: The chemical name of ammonium nitrate is a mixture of nitric acid and ammonia, with the molecular formula NH4NO3, where N represents the content of the nitrogen element.
   • Physical properties: Ammonium nitrate is a white crystalline powder, easily soluble in water but not in ethanol and ether. Its melting point is about 190°C, and its boiling point is about 167°C.
   • Thermal stability: Ammonium nitrate will undergo decomposition upon heating, generating nitrogen gas, oxygen gas, and water. At high temperatures, ammonium nitrate gradually decomposes and releases ammonia gas.
   • Chemical properties: Ammonium nitrate has strong oxidizing properties and can react with various reducing agents through displacement reactions. Under acidic conditions, ammonium nitrate undergoes hydrolysis.
   • Applications: Ammonium nitrate is mainly used to produce fertilizers, explosives, and other industrial products. It is also widely used in agricultural fertilization as a nitrogen source for crop growth.

3. Ammonium Sulfate

   • Chemical composition: The chemical name of ammonium sulfate is a mixture of sulfuric acid and ammonia, with the molecular formula (NH4)SO4, where N represents the content of the nitrogen element.
   • Physical properties: Ammonium sulfate is a colorless crystalline powder, easily soluble in water but not in ethanol and ether. Its melting point is about 204°C, and its boiling point is about 156°C.
   • Thermal stability: Ammonium sulfate does not undergo significant decomposition upon heating but may undergo slight decomposition at high temperatures.
   • Chemical properties: Ammonium sulfate has strong acidity and can react with various bases through neutralization reactions. Under acidic conditions, ammonium sulfate undergoes hydrolysis.
   • Applications: Ammonium sulfate is mainly used to produce fertilizers, pesticides, and other industrial products. It is also widely used in agricultural fertilization as a nitrogen source for crop growth.

4. Ammonium Chloride

   • Chemical composition: The chemical name of ammonium chloride is a mixture of hydrogen chloride and ammonia, with the molecular formula NH4Cl, where N represents the content of the nitrogen element.
   • Physical properties: Ammonium chloride is a colorless crystalline powder, easily soluble in water but not in ethanol and ether. Its melting point is about 109°C, and its boiling point is about 119°C.
   • Thermal stability: Ammonium chloride does not undergo significant decomposition upon heating but may undergo slight decomposition at high temperatures.
   • Chemical properties: Ammonium chloride has strong corrosiveness and can react with various metal oxides through chemical reactions. Under acidic conditions, ammonium chloride undergoes hydrolysis.
   • Applications: Ammonium chloride is mainly used to produce fertilizers, pesticides, and other industrial products. It is also widely used in agricultural fertilization as a nitrogen source for crop growth.

5. Nitro-Compound Compound Fertilizers

   • Chemical composition: Nitro-compound compound fertilizers are usually mixed with nitrates and ammonium salts, with specific formulations determined by different needs.
   • Physical properties: Nitro-compound compound fertilizers are solid granular substances, varying in color, shape, and particle size depending on the product. They have higher melting points and are not easy to burn.
   • Thermal stability: Nitro-compound compound fertilizers do not undergo significant decomposition upon heating but may undergo slight decomposition at high temperatures.
   • Chemical properties: Nitro-compound compound fertilizers have relatively high nitrogen content and lower phosphorus and potassium contents, suitable for soils requiring high nitrogen fertilizers and low phosphorus and potassium fertilizers.
   • Applications: Nitro-compound compound fertilizers are mainly used for agricultural fertilization as a nitrogen source for crop growth and can also be used as one of the main components in complex fertilizers.

these five types of nitrogen fertilizers each have their own characteristics and applicable scopes. When choosing and using nitrogen fertilizers, factors such as soil type, crop needs, and climate conditions should be comprehensively considered to achieve the best fertilization effect.