中文摘要：

【目的】近年来由于超量施用化肥导致蕉园土壤严重酸化,土壤生产力逐年明显下降,香蕉产量骤降,传统产区栽培面积锐减。为此本试验在超高密度栽培条件下,以碱性长效缓释氮肥（ALNF,N 22%）作为供试肥料,研究其降低土壤酸度的效果及对香蕉产量和氮肥利用率的影响,并进一步探讨肥料的碱性能否造成氮素的损失。【方法】本研究包括两个试验,分别为肥料种类和肥料用量对比试验,香蕉栽培密度均为3333 plant/hm～2。试验1为碱性长效缓释肥料（ALNF）、控释配方BB肥料（CRF_（BB））、常规肥料（CCF）三因素对比试验,以无氮处理（CK）为对照。试验2为完全ALNF（N 337.5 g/plant）,ALNF＋60 g尿素N（ACF1,397.5 g/plant）,ALNF＋90 g尿素N（ACF2,427.5 g/plant）,以不施氮肥（CK）为对照。【结果】超高密度栽培条件下,ALNF处理收获期土壤pH值分别比CRF_（BB）、CCF、CK、ACF1和ACF2处理提高了1.2、1.2、1.1、0.6和0.3个单位。ALNF和CRF_（BB）处理香蕉单株产量分别比CCF处理增加了43.4%和35.1%,ALNF和ACF1处理香蕉单株产量分别比ACF2增加了50.6%和40.0%。就氮素平衡而言,CRF_（BB）和ALNF处理作物携出氮量分别比CCF处理提高了48.9%和24.8%;CCF的氮素表观损失量最多,是ALNF处理的2.3倍;ALNF处理的土壤氮素残留量最多,分别是CRF_（BB）、CCF处理的1.6倍、2.4倍;ALNF处理香蕉的携氮量分别比ACF1、ACF2处理提高了5.0%、31.9%,土壤残留氮量增加了60.8%、162.6%,ALNF的氮素表观损失最少,并随着尿素添加量的增加而增加,ALNF处理的氮素表观损失量仅为ACF2的1/4。CRF_（BB）和ALNF处理的氮肥利用率分别比CCF的提高了66.7%、33.7%,ALNF处理比ACF1、ACF2处理提高了27.8%、87.7%,ACF1处理的比ACF2处理提高了46.9%。【结论】碱性长效缓释氮肥能够显著降低土壤酸度,土壤pH提高了0.3～1.2个单位,提高香蕉产量35%～50%,增加香蕉氮素吸收量24%～5

英文摘要：

【Objectives】Long term and over use of chemical fertilizers has resulted in soil acidification in banana orchards and decline of banana yield and quality. A new type of chemical fertilizer, alkaline slow release nitrogen fertilizer（ALNF,N22%）, has been prepared. The purpose of the paper was to study effects of ALNF application on soil pH value, banana yield, nitrogen use efficiency（NUE） and nitrogen losses in the soil.【Methods】 Two field experiments were conducted in banana orchard, one was fertilizer type and the other was dosage comparison experiments. The fertilizer types experiment had four treatments： alkaline slow release fertilizer（ALNF）, controlled release fertilizer blend（CRF_（BB））, conventional fertilizer（CCF） and no nitrogen treatment（CK）. The ALNF dosage experiment included following four treatments： completely ALNF（N 337.5g/plant）, ALNF＋60 g N from urea（ACF1, 397.5 g/plant）, ALNF＋90 g N from urea（ACF2, 427.5 g/plant） and no nitrogen control（CK）. 【Results】 Soil pH value was increased by 1.2, 1.2, 1.1, 0.6 and 0.3 units in the ALNF treatment compared to the CRF_（BB）, CCF, CK, ACF1 and ACF2 treatments separately under the super high density cultivation of banana. The banana fruit yields per plant in the ALNF and CRF_（BB） treatments were increased significantly by 43.4% and 35.1% compared to that in the CCF treatment. The yields of the ALNF and ACF1 treatments were 50.6% and 40.0% greater than that of the ACF2 treatment. In the N balance, the nitrogen uptakes by CRF_（BB） and ALNF treated banana plants were 48.9% and 24.8% higher than that by the CCF treated plants individually. The highest apparent loss of N was observed in the CCF treatment which was about 2.3 times of that in ALNF treatment. The highest amount of soil nitrogen residual was found in the ALNF treatment, which was about 1.6 and 2.4 times of those in CRF_（BB） and CCF respectively. The nitrogen absorption by banana in ALNF was5.0% and 31.9% higher than those of A