活化褐煤包裹尿素缓控释效果及生物毒害分析

Analysis on the Controlled/Slow Release Effect and Biological Toxicity of Activation Lignite Coated Urea

缓控释氮肥是解决速效性化学氮肥利用率低、环境污染大等问题的有效手段。研究选取无污染的含有一定量水溶性腐植酸的褐煤作为尿素的包裹材料,探索其对氮素缓控释效果的影响。浸水和土柱淋溶试验表明,活化后水溶性腐植酸含量为2～4 g/kg的褐煤作为尿素包裹材料缓控释效果最好,浸水时间可达259.55 min（尿素为2.98 min）,土柱淋溶第20次时氮淋洗累积率才达到98.06%（尿素淋洗第六次达到97.77%）。小麦发芽试验表明,发芽率活化褐煤包裹尿素比普通尿素高3个百分点。因此,活化褐煤包裹尿素具有缓控释氮肥的效果,同时不会对植物产生有害作用。

Coated controlled/slow-release nitrogen fertilizer application was one of the effective way to increase utilization of chemistry nitrogen fertilizer and decrease environment pollution. Lignite was chosen as one of non-pollution and water-solution humic acid content materials, and the controlled/slow-release effect was analyzed. Both socking and soil column leaching tests were designed to study the characteristic of nutrient release of urea coated by lignite, and the results showed that, after activation treatment, lignite contained 2～4 g/kg humic acid, and the socking time reach to 259.55 min compared to 2.98 min of urea. Nitrogen content of the leaching solution from urea coated by lignite was 98.06% after 20th soli column leaching, and that of common urea was 97.77% after 6th. The results of wheat germination test showed that wheat germination rata was high when wheat treated with urea coated by lignite compared to common urea treatment, increasing by 3%. Therefore, lignite coated urea had a positive effect on the characteristic of nutrient release has and had no toxic effect on plant growth.