我国冬油菜区土壤肥力变化及施肥效果演变

本文分析了1961—1965年、1981—1985年及2004—2006年3个时期我国冬油菜种植区的土壤肥力状况，氮、磷、钾及硼肥的施用效果，氮、磷、钾肥的农学效率及肥料贡献率。结果表明，与20世纪60年代相比，近期油菜主产区耕地土壤有机质、全氮、碱解氮、速效磷及有效硼含量大幅度上升；土壤有机质、速效磷及有效硼含量较20世纪80年代也略有增加。但由于土壤养分临界值水平的提高，近期土壤有效氮、磷、钾、硼的缺乏范围存在扩大趋势。田间肥效试验结果表明，以增产量为标准，近期施用氮、磷、钾、硼油菜籽增产高于其它两个时期。施肥在油菜籽产量中的贡献率从1961—1965年间的23．8％和1981—1985年间的54．5％增长到2004—2006年间的55．1％。总体上，我国冬油菜种植区土壤养分肥力稳中有升，但速效养分相对缺乏面积扩大；施肥对油菜籽单产的贡献率增大，油菜丰产必须建立在科学施肥的基础上。

Variation of soil fertility and evolution of fertilizer efficiency in winter rapeseed region of China

Variation of soil fertility and effect of fertilizers including nitrogen （ N）, phosphorus （ p）, potassium （K） and boron （B） on rapeseed were analyzed in winter rapeseed - growing region of China. The data came from three investigations in 1961 - 1965,1981 - 1985 and 2004 - 2006. Results showed that soil organic matter （ OM）, total N （TN）, alkali - hydrolyzable nitrogen （ AHN）, available phosphorus （Ap） and available boron （AB） in major areas were increased significantly in 2004 - 2006. The content of soil OM, AP and AB increased slightly too. But the deficiency of available soil nutrients was enlarged because of improvement of soil critical nutrient values. Results of field experiments during 2004 to 2006 indicated that increment of rapeseed yield from fertilization was much high- er than the other two periods. The contributions of fertilizers to yield were increased from 23.8% between 1961 - 1965 and 54.5% between 1981 - 1985 to 55.1% between 2004 -2006. It was concluded that soil fertility was enhanced steadily in winter rapeseed - region, but the deficient area of available - nutrients was increased. High yield ＇apeseed was based on integrated nutrient managements of N, P, K, B, etc.