Nitrogen, potassium, phosphorus content with increasing soil depth is gradually reduced.

碱解氮、速效钾、速效磷含量随着土层深度的加深逐渐降低。

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In soils with the same phosphorus levels, the contents of various forms of phosphorus were accumulated mainly in the profile of a surface layer and decreased gradually with the depth of the profile.

对于相同土壤磷水平的土壤，磷素在上层土壤积累量较大，随着土层深度的加深，磷素含量逐渐减小。

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The results show that in-depth treatment process have good removal effect for the COD, BOD, total phosphorus, ammonia nitrogen, suspended particulate, turbidity, OIL and total iron of waste water.

结果表明：深度处理工艺对源污水中COD、BOD、总磷、氨氮、悬浮物、浊度、OIL、总铁等均有很好的去除效果。

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