How do cover crops benefit soil structure?

Cover crops significantly improve soil structure primarily through the process of aggregation and by increasing organic matter content. When cover crops are grown, their roots penetrate the soil, which helps to create soil pores and enhance the soil's overall structure. These pores allow for better movement of air and water, contributing to improved drainage and water retention capabilities.

Moreover, cover crops contribute organic matter as they grow and when they decompose. This added organic matter can help bind soil particles together, leading to the formation of aggregates. Soil aggregates are clumps of soil that improve soil aeration, reduce compaction, and enhance microbial habitat, which in turn supports healthy soil ecosystems. This improvement in aggregation helps prevent erosion, promotes better root development for subsequent crops, and enhances the resilience of the soil.

While minimizing soil compaction, enhancing water retention, and preventing pest infestations are also benefits of cover crops, the core of how they directly benefit soil structure is through the mechanisms of improving aggregation and increasing organic matter content. Therefore, option B accurately captures the primary way in which cover crops influence soil structure.