Acta Scientiarum Naturalium Universitatis Pekinensis ›› 2017, Vol. 53 ›› Issue (6): 1143-1149.DOI: 10.13209/j.0479-8023.2017.126

• Orginal Article • Previous Articles     Next Articles

Effects of Nitrogen Addition on the Radial Growth of Castanopsis carlesii in Wuyi Mountain

Xinyang ZHANG1, Qiaoshuyi WANG2, Juan XING2, Faxu ZENG2, Fuqing FANG3, Chengyang ZHENG2()   

  1. 1. School of Urban Planning and Design, Peking University Shenzhen Graduate School, Shenzhen 518055
    2. School of Urban and Environmental Sciences, Peking University, Beijing 100871
  • Received:2016-05-16 Revised:2016-06-08 Online:2017-10-24 Published:2017-11-20

氮添加对武夷山米槠径向生长的影响

张歆阳1, 王乔姝怡2, 邢娟2, 曾发旭2, 方福清3, 郑成洋2()   

  1. 1. 北京大学深圳研究生院城市规划与设计学院, 深圳 518055
    2. 北京大学城市与环境学院, 北京 100871
    3. 武夷山国家公园管理局, 武夷山 354300;
  • 基金资助:
    国家自然科学基金(31021001)资助

Abstract:

The authors carried out a N enrichment experiment in Wuyi Mountain with four N addition levels (control (0), low N (50 kg N/(hm2·a)), medium N (100 kg N/(hm2·a)) and high N (150 kg N/(hm2·a))) This study was designed to study the seasonal characteristics of DBH (diameter at breast height) growth of Castanopsis carlesii and its short term response to simulated nitrogen deposition. Results show that the Castanopsis carlesii annual growth can be divided into 3 periods: water recovery period, fast growth period and slow growth period. N additions play different roles on the growth of Castanopsis carlesii. In the fast growth period (June to October), low N and medium N significantly increase the relative growth rate of annual DBH. Relative DBH growth in slow growth period (November to April) has no significant response to N addition. Among different diameter classes, N additions affect the DBH growth differently: low and medium N additions significantly promote growth in low diameter class (5 cm<DBH<15 cm) (p<0.05), but the tree growth has no significant response to high N addition. With the increase of tree diameter, the DBH growth of Castanopsis carlesii decreases sensitivity to N additions. High diameter class (DBH>25 cm) does not show significant response to N deposition. The study also finds that medium N addition significantly increase the biomass growth rate of Castanopsis carlesii in the study area (p<0.05).

Key words: tree growth, nitrogen deposition, growth stage, diameter class

摘要:

通过设置对照(0)、低氮(50 kg N/(hm2·a))、中氮(100 kg N/(hm2·a))和高氮(150 kg N/(hm2·a)) 4 种水平的氮添加实验, 研究武夷山米槠(Castanopsis carlesii)径向生长的季节特征及其对模拟氮沉降的短期响应。结果表明, 米槠的全年生长可分为水分恢复期、快速生长期和缓慢生长期3个阶段。不同生长阶段对施肥的响应不同, 低氮和中氮处理对米槠的全年胸径相对生长速率有显著促进作用, 这种影响主要在快速生长期(6— 10月)产生, 氮添加在缓慢生长期(11—4月)对米槠径向生长无显著影响。氮添加对不同径级树木生长的影响存在差异, 低氮和中氮处理显著促进低径级(5 cm<DBH<15 cm)(p<0.05)的生长速率, 高氮处理的作用不显著; 随着径级增大, 米槠径向生长对氮添加的敏感性下降, 氮添加对高径级(DBH>25 cm)米槠径向生长无显著响应。中氮处理显著提高研究区内米槠群落的生物量增长速率(p<0.05), 其他处理的效果不显著。

关键词: 树木生长, 氮沉降, 生长阶段, 径级