Kouadri Mohamed El Amine Assessing the impact of mycorrhizal fungi on nutrient cycling and soil health parameters involves measuring various indicators. Here are some steps to conduct this assessment:

1. Soil organic matter content: Measure the soil organic matter content in areas where mycorrhizal fungi have been applied compared to control areas. This can be done through laboratory analysis using methods such as loss on ignition or Walkley-Black titration.

2. Nutrient availability: Assess the availability of key nutrients in the soil, such as nitrogen, phosphorus, and potassium. This can be done using soil testing kits or by sending soil samples to a laboratory for analysis. Compare nutrient availability in areas where mycorrhizal fungi have been applied with control areas.

3. Microbial activity: Evaluate the microbial activity in the soil, particularly focusing on the mycorrhizal fungi population. This can be done using methods like phospholipid fatty acid analysis or quantitative polymerase chain reaction (qPCR) to quantify the abundance and diversity of mycorrhizal fungi.

4. Enzyme activity: Measure the activity of soil enzymes involved in nutrient cycling processes, such as phosphatase, urease, and nitrogenase. Higher enzyme activity suggests increased nutrient availability and cycling, which can be attributed to the presence of mycorrhizal fungi.

5. Soil aggregation and structure: Assess the impact of mycorrhizal fungi on soil aggregation and structure. This can be done visually by observing soil structure, or by using techniques like wet sieving and measurement of aggregate stability.

6. Nutrient uptake by plants: Evaluate the nutrient uptake by plants in areas where mycorrhizal fungi have been applied. This can be done through plant tissue analysis to determine the concentration of essential nutrients in plant tissues, comparing mycorrhizal-associated plants with non-mycorrhizal plants.

7. Plant growth and health: Monitor the overall growth and health of plants in areas where mycorrhizal fungi have been applied, including parameters such as shoot and root biomass, plant height, and disease resistance. Compare these with control areas to assess the impact of mycorrhizal fungi on plant performance.

8. Long-term monitoring: Conduct long-term monitoring to assess the sustainability of the observed effects. Measure soil health parameters and nutrient cycling indicators over multiple growing seasons to evaluate the persistence of mycorrhizal fungi benefits.