Which method is beneficial for managing soil fertility sustainably?

Utilizing green manures and cover crops is beneficial for managing soil fertility sustainably because these practices enhance soil health, improve nutrient cycling, and promote biodiversity. Green manures are typically cover crops grown specifically to be tilled back into the soil, which adds organic matter and nutrients. This practice not only improves soil structure and fertility but also helps prevent erosion and suppress weeds.

Cover crops, on the other hand, are planted during the off-season to cover the soil, reducing nutrient leaching and increasing the overall nutrient availability for subsequent crops. They also enhance microbial activity in the soil, which supports nutrient breakdown and enhances the soil's overall fertility.

In contrast, exclusive use of chemical fertilizers can lead to soil degradation over time, as it often fails to replenish organic matter and may disrupt the microbial ecosystem. Frequent monocropping can deplete specific nutrients needed by particular crops and increase vulnerability to pests and diseases. Only applying fertilizers during harvest does not address ongoing nutrient needs and can result in nutrient imbalances throughout the growing season. Therefore, the use of green manures and cover crops represents a more sustainable, holistic approach to soil fertility management.