造纸黑液木质素对尿素氮在土壤中转化与生物利用的影响

Effect of lignin from paper-making black liquor on the transformation and the bio-utilization of urea-N

利用造纸黑液木质素对尿素进行包膜处理,制成3种不同包膜厚度的缓释尿素(LCU),通过土壤淋溶试验和盆栽试验研究了木质素包膜尿素氮素释放规律和生物利用效果,结果表明:木质素包膜尿素具有不同程度的缓释性能,木质素包膜尿素中氮素累积溶出速率比普通尿素低12%;施用木质素包膜尿素的玉米生物量均大于普通尿素,尿素氮素利用率平均提高了7 8%.木质素对尿素氮转化影响除了物理控释作用外,其降解产物还具有一定的硝化抑制作用,能减少氮素的淋失和对环境的污染.

Urea coated with lignin from paper-making black liquor were made in different layer thickness. Nitrogen release rate of lignin coated with urea (LCU) in soil were determined by leaching experiment. Pot experiment was conducted to study the fertilizer efficiency of LCU, which was used as a slow-release nitrogen fertilizer, on corn. Results showed that urea coated with lignin presented slow-release property to different degree. Nitrogen release rate of LCU was about 12% lower than that of normal urea, utilization ratio of nitrogen was about 7.8% higher than that of mormal urea. the result indicated that LCU could increase the yield of the corn and utilization ratio of nitrogen compared with un-coated urea. In addition to its slow-release effect, the degradation product of lignin was an effective nitrification inhibitor, which could reduce the loss of nitrogen and protect environment from N pollution.