The main difference between urea-based and nitrate-based compound fertilizers lies in the form of nitrogen they contain. Urea-based fertilizers include urea, while nitrate-based ones contain nitrate nitrogen.

1. Nitrogen Form: Urea-based fertilizers provide nitrogen in the form of urea, an organic compound with a high nitrogen content that serves as a nitrogen source for plant growth. Nitrate-based fertilizers, supply nitrogen in the form of nitrate nitrogen, which can be directly absorbed by plants.

2. Nitrogen Utilization Rate: Due to its molecular structure, urea in urea-based fertilizers is easily decomposed by soil microorganisms, reducing nitrogen efficiency. In contrast, nitrate nitrogen in nitrate-based fertilizers is less susceptible to microbial breakdown, leading to higher utilization rates.

3. Nitrogen Stability: Urea-based fertilizers have poor stability in soil, as their nitrogen is prone to loss due to environmental factors like soil pH and temperature. Nitrate-based fertilizers, remain stable in soil and are less affected by such conditions.

4. Fertilization Effects: Although urea-based fertilizers have a high nitrogen content, their effectiveness may be limited due to rapid soil decomposition. Nitrate-based fertilizers, with better stability, generally yield superior results.

5. Economic Efficiency: Urea-based fertilizers are cheaper but may offer lower efficacy compared to nitrate-based options. Nitrate-based fertilizers are pricier but often more effective.

6. Environmental Impact: Urea-based fertilizers may cause environmental pollution due to easy decomposition. Nitrate-based fertilizers, with their stability, pose less risk of environmental contamination.

7. Suitable Crops: Urea-based fertilizers are ideal for nitrogen-demanding crops like rice and wheat. Nitrate-based fertilizers are better suited for crops with lower nitrogen needs, such as corn and soybeans.

8. Application Methods: Urea-based fertilizers can be applied simply by mixing with seeds or spreading directly into soil. Nitrate-based fertilizers require dilution with water and precise rationing before use.

the key difference between urea-based and nitrate-based fertilizers is their nitrogen form. Each type has distinct advantages and disadvantages, and the choice depends on crop requirements and soil conditions.