氮磷配施对云南松实生苗生长的影响

The Effect of Nitrogen and Phosphorus Fertilization on the Seedling Growth of Pinus yunnanensis

为解决云南松苗期生长缓慢问题,采用3×3回归设计,并汲取拉丁方和随机排列的特点进行氮、磷配合喷施试验.结果表明:生长量及生物量与氮、磷用量之间的关系符合二次抛物线方程,反应曲面为典型凸形曲面,即各生长指标均存在一个产量峰值.峰值以前,各生长指标随氮、磷用量的增大而提高;峰值以后,各生长指标随氮、磷用量的增大而下降.根据肥料效应方程求解,得到苗高、地径生长量以及根、干和叶片生物量最大时的氮、磷以及最佳N∶P的用量.对应的最高理论产量分别为10.08 cm、0.53 cm、1.211 g、0.387 g和1.217 g,分别较对照提高了39.55%、14.97%以及78%、75.1%和34.5%.其中,施肥对根系发育的作用最明显,而且各构件对肥料用量及比例的响应规律不同,较高的氮肥比例有利于促进树干的粗生长和根系发育,较高的磷肥比例有利于促进树干的高生长和各构件生物量的积累.

In order to accelerate the seedling growth of Pinus yunnanensis, the mixed spraying fertilization of nitrogen and phosphorus has been adopted by using 3 × 3 regressive design and drawing the characteristics of Latin square and random array. The results show that the relationship between the growth increment, biomass and amount of nitrogen, ＆ phosphorus can be described by quadratic parabola, and every growth index has a maximum value for the output. The growth is improved as the increasing of amount of nitrogen ＆ phosphorus in front of maximum value, while the growth is decreased as the increasing of amount of nitrogen ＆ phosphorus after maximum value. The nitrogen ＆ phosphorus optimum dosage and optimum proportion under the highest growth increment are calculated by the fertilization equations, and the highest growth increment of height, diameter, root stem and leaves are 10.08 cm, 0.53 cm, 1. 211 g, 0. 378 g and 1. 217 g respectively, and corresponding growth increment are respectively 39.55% , 14.97% ,78% ,75. 1% and 34.5% more than those contrasts. In which the root system has obviously been improved by fertilization, but the different components show different responses. In detail, the higher amount of nitrogen is advantage to the diameter growth of stem and the development of root system, and the highest amount of phosphorus is advantage to the height growth of stem and biomass accumulation.