[名词解释] 生物固氮作用(Biological nitrogen fixation)
[名词解释] 生物式传播(biological transmissin)
[名词解释] 生物需氧量(Biological Oxygen Demand)
[名词解释] 生物防治(biological control)
[名词解释] 生物处理法(Biological Process)
[名词解释] biomembrane,or biological membrane (生物膜)
[名词解释] 生物学宽度biological width,BW
[名词解释] 土壤生物活性 soil biological activity
[问答题] 简述树木根系对土体固持的实质。
[单选题]B.iological treatment may use __ to treat sewage (1)living organisms (2)chemicals (3)additivesA.(1)B.(2)C.(3)D.(1)(2)(3)