What type of nitrogen source is designed to minimize leaching and runoff?

The selection of slowly available nitrogen as the best type of nitrogen source for minimizing leaching and runoff is correct due to its unique properties that enhance nutrient retention in the soil. Slowly available nitrogen sources are designed to release nutrients gradually over time, matching the uptake needs of plants. This slow release helps to prevent excess nitrogen from being available all at once, which can lead to leaching when heavy rains occur or when irrigation takes place.

In contrast, water-soluble nitrogen and quick-release nitrogen are rapidly available to plants but can also lead to excess that is easily washed away by water, causing environmental concerns such as nutrient pollution in waterways. Immediate nitrogen sources, while beneficial for quick plant responses, further increase the risk of leaching and runoff due to their rapid availability. Therefore, slowly available nitrogen effectively reduces the potential for nutrient loss while providing plants with a consistent supply of nitrogen over an extended period.