为了提供科学合理的施肥依据,在氮、钾肥最佳用量的基础上,依次设置5个磷水平处理,对油茶幼林开展施磷肥试验。结果表明:低于每年900 g/株磷肥水平时,油茶植株的株高、地径、冠幅乘积增幅、叶绿度、叶面积及叶片养分N、P、K随着磷素供应水平的增加而增大;在每年900 g/株磷肥水平下,各项指标达到最大值;大于每年900 g/株磷肥水平时,各项生长指标没有增加反而降低了。说明过度施入磷肥,导致植株磷肥利用率的降低,影响植株体内干物质积累,不利于植株生长;不同磷水平处理中,对油茶各指标的影响呈先增大后减少的趋势。叶片养分与油茶树体指标间呈极显著相关性,施磷肥与各项指标关系密切。油茶植株营养生长对磷水平的响应,说明合理施用磷肥有利于油茶植株树体的生长和叶片养分的累积。
In order to provide scientific and reasonable fertilization basis, based on the optimum dosage of nitrogen and potassic fertilizer, a phosphorus fertilization experiment of young Camellia oleifera forest was carried out at five phosphorus levels. The results showed that when annual phosphorus fertilization level was below 900 g per plant, plant height, ground diameter and crown width increment, SPAD value, leaf area and leaf nutrient N, P, K in C. oleifera plants were increased with phosphorus fertilization level rising. When annual phosphorus fertilization level was 900 g per plant, the indexes reached the maximum values. When annual phosphorus fertilization level was over 900 g per plant, the growth indexes were decreased. So excessive phosphate fertilizer could reduce the utilization ratio of phosphate fertilizer and affect accumulation of dry matters in body, and it was not conducive to plant growth. The effects of the phosphorus level treatments on the indexes showed a trend of reducing after firstly rising. Leaf nutrient had significantly correlation with the indexes in C. oleifera plants, and phosphate fertilization was closely related to the indexes. The response of vegetative growth in C. oleifera plants to phosphorus levels showed that reasonable phosphate fertilization was advantageous to growth and leaf nutrient accumulation in C. oleifera plants.