throughfall

例句：

1. 1. The forest was blanketed with a thick layer of fallen leaves.
   森林被厚厚的落叶覆盖。
2. 2. The tree's throughfall is a valuable resource for wildlife.
   这棵树的落叶对野生动物来说是宝贵的资源。
3. 3. The throughfall of the forest is a significant source of carbon dioxide.
   森林的落叶是二氧化碳的一个重要来源。