保水缓释肥料保水性能及养分释放特性

为了明确添加水溶性保水剂(羧甲基纤维素钠、聚丙烯酰胺、聚丙烯酸钠)肥料的保水缓释效果,利用圆盘造粒工艺制备了保水缓释肥料,通过土壤培养和土柱淋溶试验,研究了保水缓释肥料在土壤中的保水性能和养分缓释效果。结果表明:3种保水缓释肥料均具有一定保水性和养分缓释效果,随保水缓释肥料用量增加,土壤最大持水率逐渐增加,土壤水分蒸发率逐渐减小;其中,以添加聚丙烯酸钠的保水缓释肥料保水性能和养分缓释效果最佳,首次淋溶后氮磷钾养分释放率较普通肥料分别减少了50.38%、55.74%、48.37%,当肥料添加量为2%时,土壤最大持水率较纯土壤提高了43.28%,培养至30 d土壤水分蒸发率较纯土壤降低了22.86%。

Water-retention and Nutrient Release Characteristic of Water-retentive Slow-release Fertilizer

In order to define the water-retention and nutrient slow-release effect of the fertilizer which added water soluble water retention agent (carboxymethyl cellulose,polyacrylamide and polyacrylate sodium),the water-retentive slow release fertilizer was made by pan granulation in this study.The water-retention and nutrient release property of water-retentive slow-release fertilizer in the soil was studied.Soil maximum water-holding rate and soil moisture evaporation rate of water-retentive slow-release fertilizer were detected by indoor incubation experiment,the nitrogen,phosphorus,potassium cumulative release rate of the water-retentive slow-release fertilizer were measured by the intermittent soil column leaching experiment.Results showed that all the three kinds of waterretentive slow release fertilizers had water-retention and slow-release effect.The soil maximum water-holding rate increased with increasing the amount of water-retentive slow-release fertilizer,but the soil moisture evaporation rate was just the opposite.Among them,the water-retentive slow-release fertilizer added polyacrylate sodium had the best water-retention and nutrient slow-release effect.For the first leaching,the nitrogen,phosphorus,potassium cumulative release rate decreased by 50.38％,55.74％,48.37％,respectively;When the application of the fertilizer was 2％,the soil maximum water-holding rate increased by 43.28％,the soil moisture evaporation rate was reduced by 22.86％ after cultivation for 30 d.