NPK量相等时，甘蔗施用有机无机肥试验研究

在连续三年的试验中研究了在ＮＰＫ养分相同的情况下，单施有机肥、有机肥＋化肥和单施化肥对甘蔗生长和对土壤农化性状的影响。结果表明，施用有机肥可以提高甘蔗的萌芽率、分蘖率，但降低了蔗糖分；施用化肥的甘蔗产量和公顷含糖量比单施有机肥的高。伸长盛期的叶片含氮量以施化肥的高，磷以施有机肥的高。各处理的土壤全氮和碱解氮含量逐年下降，速效磷含量逐年提高，有机质含量和速效钾含量有升有降。翻犁后一年的土壤有机质含量会下降，连续宿根栽培则可以提高或维持有机质含量。三年后，有机肥处理的土壤有机质、全氮和碱解氮含量下降的幅度比化肥处理的小，速效磷含量提高的幅度比施化肥的大，但处理间的差异不显著。

A Study on Organic and Mineral Fertilizer Application to Sugarcane under the Condiction of Equal NPK Amount

Under the condiction of equal NPK amount, the effects of application of organic fertilizer, mineral fertilizer and organic fertilizer plus mineral fertilizer on sugarcane growth and soil agrochemical characteristic were studied for three years. The result showed that application of organic fertilizer leaded to increase in germination rate and tillering rate,and decrease in sucrose content, that cane yield and sugar content per hectare of mineral fertilizer treatment were higher than those of organic fertilizer treatment.In the fastest growing phase, leaf nitrogen and phosphorus content were highest in mineral fertilizer treatment and organic fertilizer treatment respectively. In all treatments, soil total nitrogen and alkali-hydrolyzable nitrogen content decreased with years, active phosphorus content increased with years. As for organic and active potassium content, the trend was different among treatments. Phloughing resulted in decrease in soil organic matter content in coming year, while successive ratoon cultivation could increase or maintain soil organic matter content. After three year's study, the decrease of organic fertilizer treatment in organic matter content, total nitrogen and alkali-hydrolyzable nitrogen was smaller than other treatments, and increase in active phosphorus was larger than mineral fertilizer treatment. But, the differences among treatment were not significant.