tree layer的用法和樣例：
例句
- The community has an outstanding dominant species and the arborous layer possesses a comparatively high diversity index.
群落的優(yōu)勢種顯著(zhù)，喬木層的物種多樣性指數較高，各樣地間的植物種類(lèi)具有一定的相似性。 - C. gigantea is a uni-predominant species in the arbor layer, microphyll and simple leaf hemicryptophytes are dominated in the shrub and grass layers.
巨柏是喬木層的單優(yōu)勢種，灌木層和草本層以全緣草質(zhì)小型單葉地面芽植物為主。
