专用缓释肥的土壤氨挥发特性及其对辣椒氮磷钾吸收利用的影响

采用室内扩散模拟试验研究了施用大颗粒尿素(PUR)、辣椒专用复混肥(LCCF)、辣椒专用缓释复混肥(LSRF)土壤的氨挥发特性,并采用土培试验研究了LSRF、LCCF、普通复合肥(OCCF)、市场非包膜缓释复合肥(MSRF)对‘渝椒五号’和‘改良早丰’辣椒产量、氮磷钾养分吸收利用、土壤有机质及酶活性的影响,探讨LSRF的应用效果。结果显示,室内扩散模拟试验中,前28 d氨释放速率总体表现为PURLCCFLSRF不施肥(CK),28 d以后LSRF的氨释放速率略高于PUR和LCCF处理。培养70 d时,PUR、LSRF和LCCF的氨挥发量分别为71.87 mg·kg-1、54.29 mg·kg-1和63.49 mg·kg-1,LSRF比PUR和LCCF分别降低了24.5%和11.7%。土培试验中,LSRF处理显著提高了2个辣椒品种的果实重量,‘渝椒五号’和‘改良早丰’分别较OCCF处理增产64.7%和33.8%。与OCCF处理相比较,LSRF处理增加了土壤有机质含量、土壤脲酶、蔗糖酶和过氧化氢酶活性,提高了辣椒对氮磷钾养分的吸收利用。‘渝椒五号’和‘改良早丰’LSRF处理的氮素表观利用率较OCCF处理分别增加62.5%和123.1%,‘改良早丰’和‘渝椒五号’LSRF处理的磷素表观利用率分别较OCCF处理提高了14.0倍和3.2倍,钾素表观利用率分别较OCCF处理提高了28.7%和120.9%。

Characteristics of soil ammonia volatilization and the absorption and utilization of nitrogen, phosphorus and potassium of pepper under slow-release fertilizer application

Laboratory diffusion simulation experiment was conducted to investigate the characteristics of soil ammonia volatilization under the application of large particle urea (PUR), special compound fertilizer (LCCF), special slow-release compound fertilizer (LSRF), with no fertilization as the control. The pot experiment was meantime carried out to investigate yield, and uptake and utilization of nitrogen (N), phosphorus (P) and potassium (K) of 'Gailiangzaofeng' and 'Yujiao5' peppers under the application of LSRF, LCCF, common compound fertilizer (OCCF) and commercially non-coated slow-release compound fertilizer (MSRF). Changes in soil organic matter content and soil enzyme activity were also analyzed. The results showed that the order of the soil ammonia volatilization rate in the first 28 days of laboratory diffusion simulation experiment was as follows: PUR > LCCF > LSRF > no fertilizer (CK). Then soil ammonia volatilization rate of LSRF after 28 days of the experiment was higher than those of PUR and LCCF. Cumulative soil ammonia volatilization from PUR, LSRF and LCCF at 70 days were 71.87 mg·kg^-1, 54.29 mg·kg^-1 and 63.49 mg·kg^-1 respectively under laboratory diffusion simulation experiment. Cumulative ammonia volatilization from LSRF respectively dropped by 24.5% and 11.7% compared with PUR and LCCF under the same dose of N fertilizer. For the pot experiment, yield of 'Yujiao5' and 'Gailiangzaofeng' under LSRF respectively increased by 64.7% and 33.8% compared with OCCF, While the content of soil organic matter and activities of urease, invertase and catalase increased, plant uptake and utilization of N, P and K were enhanced under LSRF treatment. Apparent N fertilizer utilization rates of 'Yujiao5' and 'Gailiangzaofeng' respectively increased by 62.5% and 123.1% compared with that of OCCF. Apparent P and K fertilizer utilization rates of 'Gailiangzaofeng' under LSRF treatment respectively enhanced by 14.0 times and 28.7% compared with OCCF. Also apparent P and K fertilizer utilization rates of 'Yujiao5' under LSRF treatment respectively increased by 3.2 times and 120.9% compared with OCCF treatment.