氮磷叶片喷施对未郁闭刨花楠人工幼林生长的影响

The effect of nitrogen and phosphorus foliage spray on the growth of young free growing Machilus pauhoi plantations

以福建省顺昌县2.5年生未郁闭刨花楠人工林为研究对象,开展不同的氮(N)、磷(P)叶面喷施添加处理,于3月、6月、9月与12月调查其地径、株高、冠幅等生长指标,并采用双因素方差分析法分析N、P喷施处理与季节对刨花楠生长量的影响.结果表明:(1)在单施N时,刨花楠地径总生长量以中N处理的效果最好,株高与冠幅总生长量均以高N处理的效果最好;在单施P时,地径、株高、与冠幅总生长量均以高P处理的效果最好;在N、P配施时,地径、株高以低N处理的效果最好,冠幅年总生长量以高N处理的效果最好;全部处理中,以高P处理为最好,高P处理下的生物量在各个季节及年总生物量上都最大.(2)除单施P对叶片碳(C)含量,高N且N、P配施对叶片P含量和低N且N、P配施对叶片C、P含量有显著影响外,其它叶面N、P喷施处理对叶片C、N、P含量都表现为影响不显著.本研究结果可以为揭示刨花楠造林初期对养分需求的特征及养分添加对林木生长的影响机制,并为人工林培育和早期养分管理技术等提供理论指导.

This study aimed to explore the effect of nitrogen and phosphorus foliage spray on the growth of young free growing Machilus pauhoi plantations.A 2.5-year-old M.pauhoi plantation in Shunchang County,Fujian Province was selected as research object.Different levels of N and P were administered to the plantation.The growth indexes of canopy diameter（C）,diameter at ground level（D） and plant height（H） were investigated in March,June,September and December.Two-factor Variance Analysis was conducted to analyze the effects of N,P addition and different seasons on the growth increment of M.pauhoi.The results revealed that the low level N spraying had the best effect on total growth increment of D;the high level N spraying had the most remarkable effects on total growth increment of H and C under the single application of N;the high level P addition could help improve the total growth increment of D,H and C to the greatest extent when spraying P singly.With the combined application of N and P,the low level N application had the best effect on total growth increment of D and H;the high level N addition was most effective in the annual total growth increment of C.Among all treatments,the high level P spraying was related to the greatest increment in biomass of M.pauhoi.Among all treatments,the single application of P had significant effect on leaf C content,the high level N with N/P combined addition on leaf P content,and the low level N with N/P combined addition on leaf C,P content;others showed no significant effects.The study provided a theoretical guidance for the cultivation and early nutrient management of M.pauhoi plantations.