磷处理粉煤灰可作农业土壤磷源

Phosphorus treated coal combustion products (CCP-bottom ash) as an agricultural source of phosphorus.

粉煤灰(简称CCP或ash)具有改良土壤,增加植物产量的功能。此外,由于它特殊的多孔结构,也可用作吸纳并承载植物养分的载体。用NaH2PO4配制成含磷0.10mol/L浓度的溶液,对采自加拿大西安大略省Sarnia地区Lambton电厂的底灰(bottomash)进行振荡浸渍处理。结果表明,振荡浸渍66h后的粉煤灰中磷含量可达784×10-6。以磷处理粉煤灰、未进行磷处理的粉煤灰和石英砂按比例混合,作为基本生长介质进行玉米种植实验,其中实验配方设计为生长介质中含磷量分别为标准含磷浓度(50×10-6)的10%、25%、50%、75%和100%。生长26、34和46d后分别与不含磷的空白配方、施加含氮-磷-钾为0-20-0标准磷肥并控制磷含量为标准浓度(50×10-6)配方进行生物产量对比。生长实验结果表明,以磷处理粉煤灰供磷的生长介质,当含磷量为标准浓度的25%至100%时,其植物生长量就比添加标准浓度磷肥的配方好。种植46d后的生物生长量统计结果显示,含磷分别为标准浓度50%、75%和100%的实验介质中,玉米杆的鲜重较施标准磷肥介质中玉米分别增长39.46%、42.73%和46.13%;玉米杆干重依次增加29.71%、13.39%和28.87%;根鲜重平均增加16.62%;根干重平均增加14.03%。上述实验结果启示,粉煤灰可以很好地吸纳承载磷养分,并持续供给植物吸收生长,如果采用吸纳磷(或其他养分)的粉煤灰改良砂质土壤将有重要意义。

Coal combustion products（CCP or ＂ash＂）have been shown to be beneficial for improving soil quality and increasing vegetative yields.Because of their structure with more holes,they are also potential carriers of plant nutrients.The bottom ash from the Lambton Generating Station,Sarnia,Ontario,Canada were treated for 66 hours in 0.10 mol/L phosphorus solutions prepared from NaH2PO4,which resulted in the ash adsorbing 784×10-6 of phosphorus.The ash was mixed with quartz sand and/or non P-loaded ash from the same source to provide a set of growth media that contained 10%,25%,50%,75% and 100% of the recommended dose of phosphorus（50×10-6）for maize.The biomass yields on the 26th,34th and 46th day after the planting were compared with those obtained by use of growth media with non-doped ash and with 0-20-0 standard P-fertilizer.The results showed that in general,the growth media containing 25% to 100% of the recommended phosphorus dose performed as well as or better than the growth media with standard P-fertilizer did.On the 46th day after the planting,the shoot fresh weight for the 50%,75% and 100% doped media increased 39.46%,42.73% and 46.13%,respectively,compared to the trials with P-fertilizer.Shoot dry weight increased 29.71%,13.39% and 28.87%,respectively,compared to the trials with P-fertilizer.Also,root fresh and dry weight increased 16.62% and 14.03% in average.This results implied that the coal ash is a better carrier for phosphorus,and the P-loaded ash can be a good additive for improving sand soil.