有机与常规稻田排水污染比较研究

Study on Comparative Runoff Pollution of Organic and Conventional Rice Fields

[目的]研究有机与常规水稻生产径流污染状况。[方法]定点采样测定总氮、总磷和COD,比较2种水稻生产方式排水污染物浓度。[结果]有机水稻生产可降低排水中氮的排放,西渚常规稻田排水中总氮浓度最高是有机的8.0倍;稻田排水中,磷的含量总体上较低(0.019-0.176mg/L),常规稻田排水中总磷浓度有高于有机水稻田的趋势,但有机稻田也会出现总磷高于常规稻田的风险;有机水稻生产由于采用"稻鸭共作"模式,排水中COD浓度总体上有高于常规大田的趋势。[结论]有机水稻种植要适当控制稻田鸭子的放养数量或改变放养方式,以避免产生不利的环境影响。

[Objective]The aim was to compare the runoff pollution of organic and conventional rice production.[Method]The runoff of the two types of rice fields were analysed by determining the fixed samples of total nitrogen,total phosphorus and COD.[Result]The results showed that organic rice production could reduce the nitrogen discharge,and the maximum concentration of TN in conventional field runoff was the eight times higher than that of organic in Xizhu field.The content of the Phosphorus was generally low（0.019-0.176 mg/l）but the concentration of the TP in conventional fields＇ runoff was generally higher than that of organic fields,although the opposite could happen sometimes.Due to ＂rice-duck farming＂ mode in organic rice production,the concentration of COD was higher than that of conventional fields in general.[Conlusion]In order to avoid the disadvantage environmental impacts,the number of the duck should decreased and the mode of ＂rice-duck farming＂ should adjusted.