Once the humus layer disappears, nutrients cannot be recycled and leach from the soil, converting soil from fertile to infertile and making it suitable only for savanna vegetation.

一旦腐殖质层消失，养分就无法从土壤中回收和过滤，致使土壤由肥沃变为贫瘠，只适于热带草原植被的生长。

youdao

Main site factors in different groups of site type existed obvious difference, for instance the altitude, the thickness of humus layer and the slope.

不同立地类型组的海拔、腐殖质层及坡向等各主要立地因子存在着显著的差异。

youdao

Humus layer in different forest types and soil surface type and quantity of soil fungal communities have a significant difference.

不同林型腐殖质层和土壤表层的土壤真菌群落种类和数量都具存在显著差异。

youdao

Porter, and he volunteered seventy acres of land where he had grown only cotton or corn for twenty-eight years, applied no fertilizer, and almost completely depleted the humus layer.

NEWYORKER: Testing, Testing