As one type of land-treatment technologies ,Constructed rapid infiltration (CRI) system was stemmed from the fast infiltration systerm,which used the applicability of fast infiltration media to replace the natural soil. Compared with other ecological process ,the CRI system has the characteristics of high hydraulic loading and less land area possession.From the previous experiment, the characteristic of low nitrogen removal rate has restricted the CRI system. This article emphatically syudy the trans...