为给栓皮栎(Quercus variabilis L.)苗木培育合理施肥提供理论依据,研究了其当年生播种苗高径生长、生物量积累和分配及苗体N、P、K质量分数的年变化规律.结果表明:①栓皮栎播种苗当年高径生长有2次高峰,其间生长量分别占全年总量的94.3％和95.6％；②8月为苗木生物量积累高峰期,该月生物量净增量(3.664g·株-1·月-1)占全年总量的47.5％.而初期(5-7月)苗木以地上生物量积累为主(生物量占整株比例从63.7％升至70.1％),中后期(7月底后)根系生长加速(生物量占整株比例从29.9％升至59.5％)；③器官N、P、K质量分数,初期(5月)较高,中期(6-9月)较低.后期(10月),根的N、P、K质量分数有所回升,茎相对稳定,叶持续下降.从1-0苗体N、P、K质量看,栓皮栎播种苗当年生长3元素积累量分别为:107、9、31mg·株-1.%An experiment was conducted to study the annual growth dynamics in height, diameter at ground level, accumulation and allocation of biomass, and contents of N, P, K in Quercus variabilis seedlings in older to provide a theoretical foundation for fertilizer application. Results indicated that there were two peaks in height and diameter at ground level of Q. variabilis seedlings in the first growing season, and the increments for the two periods accounted for 94.3% and 95.6% of the total biomass in the whole growing season, respectively. An obvious increase in biomass accumulation was observed in August, and the biomass increment was 3.664 g per seedling per month, accounting for 47.5% of the total biomass for the whole year. Q. variabilis seedlings allocated more biomass to the aboveground parts during the early growing period (May to July) , and the biomass ratio of aboveground parts to the whole plant increased from 63.7% to 70.1%. However, the seedlings allocated relatively more biomass to roots after the end of July, and the biomass ratio of roots to the whole plant raised from 29.9% to 59.5%. Contents of N, P, and K in different organs were the highest at the end of May, and then decreased from June to September. However, the contents of N, P, and K in roots rose again to some extent at the late growing season (October), while those in stems kept at a relatively stable level, and those in leaves descended to the lowest degree. Furthermore, the average contents of N, P, and K in one-year-old Q. variabilis seedlings were 107, 9, and 31 mg per seedling, respectively.
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