聚丙烯酰胺对橡胶树专用肥养分淋出特性的影响

Effect of Polyacrylamide(PAM) on Nutrient Leaching Characteristics of Fertilizer for Rubber Tree

为确定不同施肥时期橡胶树专用肥中聚丙烯酰胺最佳用量及其养分释放特性,利用间歇式性土柱淋溶试验,通过模拟海南省4、6、9月的降雨量,探究不同降雨量条件下聚丙烯酰胺对橡胶树专用肥养分淋出特性的影响。结果表明:在不同降雨量条件下,橡胶树专用肥氮钾累积淋出量总体上均表现为随着聚丙烯酰胺用量增加而减少;6次淋溶结束时,模拟4、6、9月降雨量条件下添加6%聚丙烯酰胺橡胶树专用肥氮累积淋出量分别占总施氮量的22.88%、50.92%、59.04%,钾累积淋出量分别占总施钾量的35.38%、69.93%、68.81%,且均显著小于未添加聚丙烯酰胺的处理。可见,在不同橡胶树施肥时期,添加聚丙烯酰胺均可有效延缓橡胶树专用肥养分释放,减少养分淋失,且当聚丙烯酰胺用量为6%时橡胶树专用肥缓释效果最佳。

In order to determine the optimum amount of PAM for the rubber tree special fertilizer and confirm nutrient release characteristics, the intermittent soil column leaching test was used to discuss the effect on characteristics of PAM to rubber tree special fertilizer nutrient leaching under simulation Hainan rainfall in April, June, September. The results showed that the accumulative nitrogen/potassium leaching were generally characterized by decreased as the increased of PAM under different rainfall conditions. At the end of six times leaching under simulation Hainan rainfall in April, June, September, when the amount of PAM was 6%, the accumulative nitrogen leaching in the ratio of total amount of nitrogen were 22.88%, 50.92%, 59.04%, respectively; the accumulative potassium leaching in the ratio of total amount of potassium were 35.38%, 69.93%, 68.81%, respectively, and significantly less than the treatment of without PAM. So in the different rubber tree fertilization time, adding PAM can effectively delay the nutrient release of rubber tree special fertilizer, reduce nutrient leaching, and the effect of slow release for rubber tree special fertilizer was the best while the amount of PAM was 6%.