摘要
【目的】探究毛竹中肥料N素分配状况与N肥利用率,为毛竹林的精准施肥及可持续经营提供科学依据。【方法】在立地条件一致具有典型性、代表性的毛竹纯林,设置6块20 m×20 m样地,包括施肥处理和不施肥处理,每个样地内设置一5 m×5 m的样方,在样方内应用^(15)N示踪技术,通过施用^(15)N标记尿素,分析N素的分配状况和利用率。【结果】1)不同年龄毛竹之间,^(15)N分配率、N肥利用率及^(15)N占总N素比例均表现为:1年>3年>5年,1年与3年、5年差异显著(P<0.05),3年与5年差异不显著(P>0.05)。2)不同器官之间,1年生竹的竹秆、竹蔸和竹叶具有较大的^(15)N分配率和N肥利用率,3年与5年生竹为竹秆、竹鞭和竹蔸,林分水平上为竹秆、竹根和竹鞭;1年生竹的竹根、竹蔸和竹叶中^(15)N占总N素的比例较大,3年和5年生为竹鞭、竹根和竹蔸。3)林分对N肥的利用率较低,为13.96%±0.88%。【结论】新竹能有效利用N肥,随竹龄增长,地下器官(竹蔸、竹鞭和竹根)在N肥利用上的优势地位逐渐增强,可以考虑加强对新竹和鞭根集中分布区施肥来促进N肥的有效吸收利用。整个林分水平上,毛竹对N肥的吸收利用较差,对其原因需进行深入研究。
【Objective】Moso bamboo（ Phyllostachys edulis） is an important ecological and economic bamboo species and it is critical to figure out how to increase its nitrogen（ N） fertilizer use efficiency in the intensive management process. This study was conducted in an intensively-managed moso bamboo forest in Lin＇an city,Zhejiang province,and aimed to explore the utilization and distribution of N fertilizer accurately,in order to provide a scientific support for precise fertilization and sustainable forest management. 【Method】In this study,we set 6 sample plots with 20 m × 20 m in size.These plots were fertilized or unfertilized,and each of them contained a quadrat with 5 m × 5 m in size. By using ^15N-urea and ^15N tracer technique in the quadrat,we investigated the distribution in the bamboo and the N fertilizer use efficiency（ NUE） derived from N fertilizer. 【Result】The ^15N distribution ratio（^15NDR） and NUE were different between different ages of bamboos,with 1 a〉 3 a 〉5 a. One-year-old bamboo had significantly greater distribution ratio and NUE than the other two ages,whereas there was no significant difference in the distribution ratio and NUE between the latter ages.As for different organs,the culm,underground culm and leaf had higher ^15NDR and NUE in one-year-old bamboo,while the underground culm and rhizome had higher ^15NDR and NUE in 3- and 5-year-old bamboos. Meanwhile,the root,underground culm and leaf in one-year-old bamboo had higher ratio of ^15N to total N,while the rhizome,root and underground culm in 3- and 5-year-old bamboos had higher ratio of ^15N to total N. The NUE of the bamboo forest was lower,with only 13. 96% ± 0. 88%. 【Conclusion】Young bamboo was able to absorb N from fertilizer more efficiently,while the underground organs had an increasing trend toward using fertilizer with increased age, suggesting that strengthening fertilization to young bamboo and underground organs could greatly promote fertilizer use efficiency.Moreover,moso bamboo forest had lower N fertilizer use efficiency,which deserves further researches in the future.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2016年第5期64-70,共7页
Scientia Silvae Sinicae
基金
国家林业局948项目"毛竹林土壤氮循环15N示踪监测技术引进"(2013-4-55)
关键词
毛竹
^15N示踪技术
分配
利用率
Phyllostachys edulis
^15N tracer technique
distribution
use efficiency
