整地施肥对I-69杨人工林生长效应的研究

在淮北平原宿县,通过大穴整地、施肥改良砂姜黑土、营造Ⅰ-69杨的五年试验证明,大穴整地当年效应明显(径、高增长19.8%、91.8%);头二年肥效不显;第三年起N肥、有机肥、N×有机肥交互作用效应极显著(材积增加77%),施P+K肥效应较差,N+K肥和N+P肥经济效益较高,投入/产出为1/6.22和1/3.78;材积增加60%和58%。整地加施肥综合效益明显,有效施肥占综合效益85.1%～88.8%。

RESEARCH ON GROWTH RESPONSE OF POPULUS DELTOIDES CV. "LUX" TO SITE PREPARATION AND FERTILIZATION

The experiment was conducted on lime concretion fluvo-aquic soil. This soil with clayed texture, compact soil body and low nutrient content is a low productive soil in the North China Plain. 5 Years' trial proved that the site preparation of big pit produced remarkable growth response with 19.8 % and 91.8 % of increment in D. B. H. and height respectively in the first year after planting; fertilization couldn't significantly increase growth in the first 2 years after planting; but N fertilizer, organic manure and the interaction between N fertilizer and organic manure had the significant and positive effects on the tree growth while the application of P K decreased the growth from the third year to the fifth year after planting. Tree volume in the treatment fertilized with N fertilizer and organic manure was increased by 77%. Treatments N K and N P increased volume by 60 % and 58 % respectively and produced a high economic benefit, the values of input/output for these 2 treatments were 1:6.22 and 1:3.78 respectively. The integrated benefit of site preparation plus fertilization was remarkable, and 85.1 %~88.8 % of the benefit was due to available fertilization.