1、Detection methods of ammonia nitrogen in water: A review

Herein, recent developments in optical detection, electrochemical detection, and biological enzyme detection systems for aqueous ammonia nitrogen detection are reviewed.

2、Ammonium Content Determination by Different Analytical Methods in the

There is not enough research to assess which analytical method is the most appropriate for the determination of (NH 4+) in manure with additives such as perlite, vermiculite, or peat. We compared three analytical methods for NH 4+ determination: distillation, ionometry, and spectrophotometry.

3、ISO 25475:2016

The method is applicable to all nitrogenous fertilizers including compound fertilizers, in which nitrogen is found exclusively either in the form of ammonium salts or ammonium salts together with nitrates.

4、Testing protocol ensures the authenticity of organic fertilizers

We analyzed their ammonium content, C:N ratio and stable nitrogen isotope ratio, and for each metric we set thresholds that flag products with a high probability of adulteration. The protocol...

5、Determination of Ammonium in Organic Fertilizer

The approach allows precise measurement of ammonium, a critical component in nitrogenous fertilizers, which is crucial for assessing fertilizer quality and reducing their environmental impact.

AOAC 981.02 – Testing Ammonium Content in Fertilizer Mixtures

AOAC 981.02 requires laboratory testing for ammonium content in fertilizer mixtures using a combination of titration and ion exchange chromatography techniques.

Fertilizer Analysis

Analysis of fertilizers refers to the examination of various elements present in fertilizers, such as nitrogen, phosphorus, and potassium, using techniques like atomic absorption spectrometry (AAS) to detect concentrations of both essential and toxic trace elements.

Determination of ammonium and nitrate in soils by digital colorimetry

Ammonium is determined as an indophenol dye, and nitrate is determined as an azo dye. The original procedures were modified to overcome the lower sensitivity of the digital colorimetric method.

Enhancing Crop Nitrogen Efficiency: The Role of Mixed Nitrate and

Improving nitrogen use efficiency in crops is essential for sustainable agricultural development. This review discusses how a balanced mixture of nitrate (NO 3−) and ammonium (NH 4+) nitrogen can significantly enhance plant growth and nitrogen use efficiency.

Fertilizer Sampling and Analysis Recommendations

This recommendation was prepared by the IFA Working Group on the Harmonization of Fertilizer Sampling and Methods of Analysis. This document is available to the general public and is a reference docum...

Determining the quality of ammonium nitrogen fertilizers requires a comprehensive evaluation of their chemical properties, physical characteristics, and application effects. The following methods and suggestions provide detailed guidance:

1. Appearance and Packaging

• Color: Ammonium nitrogen fertilizers typically appear white or light yellow due to reactions between ammonia molecules and other components. Abnormal colors (such as dark brown or black) may indicate impurities or the presence of other chemicals.
• Packaging: Check for intact packaging and clear labels. High-quality fertilizers usually include detailed information such as production date, expiration date, and ingredient content.

2. Solubility

• Dissolution Rate: Place a small amount of fertilizer in water and observe its dissolution speed. Quality ammonium nitrogen fertilizers dissolve rapidly, forming a clear solution. Slow or incomplete dissolution may suggest impurities.
• Solution Stability: After dissolving, allow the solution to sit. High-quality fertilizers produce little to no precipitate and remain clear.

3. Odor and Taste

• Odor: Smell the fertilizer. While ammonia has a pungent smell, quality ammonium nitrogen fertilizers typically have a mild odor. Strong or unusual smells (e.g., intense ammonia or other abnormal odors) may indicate poor quality.
• Taste: Taste the fertilizer cautiously. Quality products should have a sweet and fresh flavor without strange tastes. Bitter or sour flavors suggest the addition of other chemicals.

4. Granule Morphology

• Particle Size: Evaluate the size and uniformity of granules. High-quality fertilizers have moderate, evenly distributed particles with no significant clumping. Oversized, undersized, or clumped granules may signal poor quality.
• Shape: Granules should be smooth and round without sharp edges or defects. Irregular shapes or flaws may reflect production issues.

5. Safety

• Harmless Treatment: Ensure the fertilizer has undergone harmless treatment to avoid health risks from residual harmful chemicals.
• Environmental Standards: Verify compliance with local environmental regulations, as standards vary by region to prevent pollution.

6. Price and Cost-Effectiveness

• Market Price: Be wary of unusually low prices, which may indicate subpar ingredients or manufacturing shortcuts.
• Value: Compare price and performance. Select cost-effective options by evaluating different brands and products.

7. Application Effects

• Crop Growth: Observe plant health. Robust growth is a key indicator of fertilizer quality. Poor growth or disease may warrant investigating fertilizer use.
• Yield and Quality: Assess crop yield and quality. Superior ammonium nitrogen fertilizers enhance both. Comparative experiments provide accurate evaluations.

a combination of these factors helps accurately judge the quality of ammonium nitrogen fertilizers. For best results, purchase from reputable sources, follow usage instructions, and prioritize safety and efficacy.