Abstract:

In order to study the effective utilization of middle-low-grade phosphate rock, pot experiments of rape and Brassica chinesis were conducted to evaluate the long-term effectiveness of phosphate rock powder activated by mechanochemistry and phosphorus activator. The results showed that, the dry weight, chlorophyll content and total phosphorus of potted rape treated by triple superphosphate were significantly greater than that of phosphate rock. To Brassica chinesis, the dry weight, chlorophyll content and total phosphorus treated by phosphate rock B added up with black liquor sludge and low-molecular-weight organic acids had no significant difference with that of triple superphosphate. To the content of rapidly available phosphorus in the river sand, the triple superphosphate treatment presented a straight line down from 0 to 50 days, reduced by nearly 40 mg/kg, and the changes after 50 days were relatively smooth; the phosphate rock treatment had a smooth change and the content of rapidly available phosphorus treated by phosphate rock reached the highest around 40 days. The results indicated that, although the effectiveness of phosphate rock activated by mechanochemistry and phosphorus activator could not reach that of triple superphosphate at first, it had a long-term effectiveness and could reach the effectiveness of triple superphosphate later.