black cotton clay

例句：

1. 1.The black cotton clay is rich in nutrients and can be used for planting.
   这种黑棉花土富含养分，可以用来种植。
2. 2. The black cotton clay has been used as a natural fertilizer for centuries.
   这种黑棉花土被用作天然肥料数百年。
3. 3. The black cotton clay is known for its ability to retain moisture and improve soil quality.
   这种黑棉花土因其保持水分和改善土壤质量的能力而闻名。