sedimentum[医] 沉淀, 沉积物sedimentn.沉淀物sediment accumulation泥沙淤积sedimentation feature沉积特征sedimentation section沉降区sedimentation of coke焦炭沉积sedimentary condition沉积条件sediment runoff curve固体径流曲线sedimentation chamber沉淀槽sedimentation balance沉积天平,沉降天平sediment concentraion含沙量sediment incrustation积垢,锅炉水垢,沉积水垢

1. The lack of humus and the excessive leaching make this soil almost useless for agricultural purpose.
   缺少腐殖质和过度淋滤使这种土壤对农业几乎无用。
2. The humus properties and mineral composition of clay have the distinct features of zonality.
   腐殖质性质及矿物组成具有明显的地带性烙印。