不同土壤淋洗方式下有机-无机复合材料胶结包膜肥料氮素溶出速率比较

应用采用水基成膜法研制的4种有机-无机复合材料胶结包膜肥料(B2、PS、F2、F2F)进行土柱淋洗试验,研究其在不同土壤类型条件下的氮素溶出规律。结果表明:4种胶结包膜肥料氮素累积溶出率达到50%所需时间为B2 42 d左右、PS 36 d左右F、2 30 d左右F、2F 18~24 d;B2的累积溶出率曲线最平缓,其后依次为PS、F2和F2F。同一种胶结包膜肥料在红壤、褐土和黑土中的氮素溶出率峰值出现时间一致(以B2为例);氮素溶出峰值之前,瞬时溶出率在2~13 d内为红壤褐土黑土,峰值氮素溶出率为红壤(12.84%)褐土(10.15%)黑土(8.39%),而峰值过后,24~48 d氮素瞬时溶出率褐土最高,红壤与黑土之间差异不显著(P0.05)。说明包膜肥料本身释放氮素的速率受不同质地的土壤影响较小,但其淋出量受土壤影响较大。

Comparison of nitrogen dissolved rate for organic-inorganic complex materials cement and coated fertilizer in different soils

Four kinds of organic-inorganic complex materials cement and coated fertilizer developed with a way of water as the solvent and coating were carried out to study the nitrogen dissolving rate under different ways of soil-column leaching. The results showed that when nitrogen accumulated dissolution rate was 50%, the time was 42 d, 36 d, 30 d and 18～24 d for B2, PS, F2 and F2F respectively. The curve of accumulated dissolution rate was the gentlest for B2, and then PS, F2 and F2F. The appearing peak time of nitrogen accumulated dissolution was the same for the same kind of cement and coated fertilizer. With B2 as an example, before peak time of nitrogen accumulated dissolution rate, instant dissolving rate in 2～13 d was the highest in red soil, and then drab soil and black soil. After the peak, nitrogen instant dissolving rate in 24～48 d was the highest in drab soil and the differences were not significant between red soil and black soil(P＜0.05). The effects of the texture were little on nitrogen dissolving from cement and coated fertilizer but great on the leaching amount.