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长白落叶松实生苗追施氮肥关键技术研究
Studies on Key Techniques of Nitrogen Top Dressing for Larix Olgensis Henry Seedlings
【作者】 马跃;
【导师】 刘勇;
【作者基本信息】 北京林业大学 , 森林培育, 2010, 硕士
【摘要】 长白落叶松(Larix olgensis Henry)是我国东北地区主要的速生用材树种之近年来,由于速生丰产林工程的全面推进,长白落叶松苗木的需求量也越来越大。长白落叶松苗木施肥的意义在于发掘土地、气候、良种的生产潜力,维持土壤养分平衡,保证单位时间、单位面积苗木稳产、高产,提高苗木产量与质量,为东北地区人工造林提供优质苗木。氮(N)是苗木发育的关键因子之一,在苗木生长季的各个阶段,氮的供给都很重要。在长白落叶松施肥技术的实际应用中,苗期追肥主要施用尿素,人工撒施于行间圃地,之后大水漫灌或喷灌,往往造成氮肥利用率低等问题。研究长白落叶松苗期追肥技术的各方面问题不仅在理论上有意义,在生产实践中也具有一定的指导价值。本研究采用裂区设计和正交设计等方法,研究了追施氮肥量、追肥时间、追肥比例、追肥方式对长白落叶松播种苗和移植苗苗木生长量和各器官氮素分配的影响。结果表明:1)追施氮肥量对长白落叶松播种苗和移植苗的生长都有显著影响,最佳追氮量均为120 kg·ha-1;2)播种苗第三次追肥最佳时间为8月中旬,移植苗最佳追肥时间为7月初。3)长白落叶松播种苗三次追施氮肥的最佳比例为1:2:2。4)对于长白落叶松苗木来说,撒施后及时喷水和水施氮肥这两种追肥方式差异并不显著,考虑到人工及肥料成本等因素,撒施条件下追氮量为120 kg·ha-1是最佳组合。
【Abstract】 Larix olgensis Henry is one of the most important rapid growth and high yield timber species in northeast China. Nitrogen is one of the key nutrient for Larix olgensis seedling growth and hence the supply of nitrogen in each growth stage is very important. This paper systematically studied Larix olgensis seedling fertilization technique, including urea fertilization requirement, top dressing time, top dressing proportion and the methods of the fertigation. The height of seedling, caliper, biomass and nitrogen distributions of root, stem and leaf were studied through Larix olgensis seedling. The main results are as follows:1) The influences of different amount of nitrogen top dressing on the seedling height, caliper, biomass and the content of N in plants was significant. The optimum amount of fertilization is 120kg·ha-1; 2) The suitable time of top dressing for transplant seedling (1-1) i early July and the suitable last time fertilization for 1-0 seedling is in Mid-august; 3), The best top dressing proportion is 1:2:2 for 1-0 seeding seedlings.4), Broadcast application suits Larix olgensis seedling.
【Key words】 Larix olgensis Henry; Nitrogen; Top dressing; Transplant seedling; Seeding seedling;