zhè / piàn / sēn / lín / de / shēng / wù / liàng / yīn / cháng / qī / gān / hàn / ér / míng / xiǎn / xià / jiàng

这片森林的生物量因长期干旱而明显下降。

The biomass of this forest has declined significantly because of prolonged drought.