水利学报
水利學報
수리학보
2014年
6期
682-690
,共9页
刘孝利%曾昭霞%陈求稳%邹慧玲
劉孝利%曾昭霞%陳求穩%鄒慧玲
류효리%증소하%진구은%추혜령
生物炭%石灰%稻田%重金属%面源输出负荷
生物炭%石灰%稻田%重金屬%麵源輸齣負荷
생물탄%석회%도전%중금속%면원수출부하
biochar%lime%paddy field%heavy metal%non-point source loading
生物炭、石灰以其良好的有毒金属固化与生态环境效应成为近年来土壤污染修复及作物安全生产研究的热点。选取典型重金属复合污染水稻田开展原位实验，分析不同原料生物炭、石灰添加处理对稻田淹水溶解态 Cd、Pb、Zn、As析出特征及其自然降雨事件面源输出负荷的影响。生物炭添加为20 t/hm2，石灰添加为750 kg/hm2。通过连续2年的观测与实验得出，稻田淹水期溶解平衡后，与对照相比，稻秆生物炭添加稻田水中溶解态 Cd、Pb、Zn浓度分别降低56%~80%、60%~75%和63%~90%，豆秆生物炭添加溶解态 Cd、Pb、Zn浓度分别降低61%~83%、51%~76%和55%~80%，石灰添加可略微降低 Cd、Pb、Zn浓度，但差异不显著。2种原料生物炭添加比石灰和对照处理均显著提高了稻田水中溶解态 As浓度。因此，自然降雨过程，稻秆和豆秆生物炭添加均可显著降低溶解态 Cd、Pb、Zn面源输出负荷，但明显增加溶解态 As面源负荷，加大受纳水体 As超标风险。因降雨和径流量的变异较大，Cd、Pb、Zn、As的面源输出负荷季节性规律尚不明显。
生物炭、石灰以其良好的有毒金屬固化與生態環境效應成為近年來土壤汙染脩複及作物安全生產研究的熱點。選取典型重金屬複閤汙染水稻田開展原位實驗，分析不同原料生物炭、石灰添加處理對稻田淹水溶解態 Cd、Pb、Zn、As析齣特徵及其自然降雨事件麵源輸齣負荷的影響。生物炭添加為20 t/hm2，石灰添加為750 kg/hm2。通過連續2年的觀測與實驗得齣，稻田淹水期溶解平衡後，與對照相比，稻稈生物炭添加稻田水中溶解態 Cd、Pb、Zn濃度分彆降低56%~80%、60%~75%和63%~90%，豆稈生物炭添加溶解態 Cd、Pb、Zn濃度分彆降低61%~83%、51%~76%和55%~80%，石灰添加可略微降低 Cd、Pb、Zn濃度，但差異不顯著。2種原料生物炭添加比石灰和對照處理均顯著提高瞭稻田水中溶解態 As濃度。因此，自然降雨過程，稻稈和豆稈生物炭添加均可顯著降低溶解態 Cd、Pb、Zn麵源輸齣負荷，但明顯增加溶解態 As麵源負荷，加大受納水體 As超標風險。因降雨和徑流量的變異較大，Cd、Pb、Zn、As的麵源輸齣負荷季節性規律尚不明顯。
생물탄、석회이기량호적유독금속고화여생태배경효응성위근년래토양오염수복급작물안전생산연구적열점。선취전형중금속복합오염수도전개전원위실험，분석불동원료생물탄、석회첨가처리대도전엄수용해태 Cd、Pb、Zn、As석출특정급기자연강우사건면원수출부하적영향。생물탄첨가위20 t/hm2，석회첨가위750 kg/hm2。통과련속2년적관측여실험득출，도전엄수기용해평형후，여대조상비，도간생물탄첨가도전수중용해태 Cd、Pb、Zn농도분별강저56%~80%、60%~75%화63%~90%，두간생물탄첨가용해태 Cd、Pb、Zn농도분별강저61%~83%、51%~76%화55%~80%，석회첨가가략미강저 Cd、Pb、Zn농도，단차이불현저。2충원료생물탄첨가비석회화대조처리균현저제고료도전수중용해태 As농도。인차，자연강우과정，도간화두간생물탄첨가균가현저강저용해태 Cd、Pb、Zn면원수출부하，단명현증가용해태 As면원부하，가대수납수체 As초표풍험。인강우화경류량적변이교대，Cd、Pb、Zn、As적면원수출부하계절성규률상불명현。
Owing to the strong ability to immobilize some toxic heavy metals immobilization in contaminated soils,biochar and lime received increasing interests from the community of soil remediation and crops safe?ty in recent years. This study conducted a two-year in situ field experiment in a paddy soil which had been contaminated by complex heavy metals,in Hunan province,China. The objective is to investigate the effects of different treatments of biochars and lime additives on the solution and non-pointe load of Cd, Pb,Zn. The additive rate was 20 t/hm2 for biochars and 750 kg/hm2 for lime. The results show that rice bio?char additive evidently reduced soluble Cd, Pb, Zn concentrations in waterlogged paddy by 56 %~80 %, 60 %~75 %, 63 %~90 % respectively, and bean biochar additive reduced soluble Cd, Pb, Zn concentra?tions by 61%~83%,51%~76% and 55%~80% respectively,comparing to the control treatment. No ob?vious changes of soluble Cd, Pb, Zn, As concentrations was observed in the treatment of lime application compared to the control treatment. However,both rice and bean biochar additives significantly increased sol?uble metalloid As concentrations in waterlogged paddy,compared to the lime additive and the control treat?ments. In conclusion, both rice and bean biochar applications could significantly decrease the non-point load of Cd, Pb and Zn during rainfall events, while increase the non-point load of metalloid As, leading to higher risk of As contamination of the receiving water. No obvious seasonality of non-point load of Cd, Pb,Zn and As was observed in this study,which may be due to the large variation of precipitation.
