摘要
【目的】了解雷州半岛不同品种桉树(Eucalyptus spp.)速生人工林生态系统的碳、氮、磷分配格局及化学计量特征,为其科学经营提供依据。【方法】选取雷州半岛赤桉(E.camaldulensis)、粗皮桉(E.pellida)、托里桉(E.torelliana)、尾叶桉(E.urophylla)人工林为研究对象,以湿加松(P.elliottii×P.oaribaea)人工林为对照,对各桉树人工林生活叶、凋落物及土壤(0~20cm)的碳、氮、磷含量及化学计量特征进行测定分析。【结果】各桉树林分有机碳和全氮含量均表现为生活叶>凋落物>土壤,且其有机碳和全氮含量均存在显著差异;不同桉树品种生活叶全氮含量显著高于湿加松,有机碳含量均显著低于湿加松;托里桉凋落物全氮含量高于或显著高于其他桉树品种,与湿加松无显著差异;湿加松土壤全磷含量显著高于各品种桉树土壤;不同品种桉树人工林凋落物C/N为39.43~63.35,表明研究区人工林凋落物分解速率较慢,氮元素成为限制凋落物分解的主要元素;8a生赤桉和10a生粗皮桉土壤C/N显著高于10a生托里桉、高于15a生尾叶桉和湿加松,说明10a生托里桉及15a生尾叶桉和湿加松表层土壤具有较快的矿化速率;相关性分析表明,生态系统内部碳、氮、磷元素已在植物、凋落物与土壤之间实现了运输和转换。【结论】雷州半岛不同品种桉树及湿加松人工林下凋落物分解速率较慢,氮元素是限制分解的主要元素;相比各桉树品种,湿加松具有较高的植物营养利用效率及固碳能力;不同桉树品种及湿加松生长限制性元素有所不同,建议在雷州半岛人工林种植过程中,及时补充多元素复合肥,充分发挥氮、磷、钾等元素的使用效果。
【Objective】This study analyzed the distribution pattern and stoichiometric characteristics of carbon（C）,nitrogen（N）and phosphorus（P）in different Eucalyptusplantations on the Leizhou Peninsula to provide theoretical basis for scientific management.【Method】E.camaldulensis,E.pellida,E.torellianaand E.urophyllafast-growing forest stands were selected to measure and analyze contents and stoichiometric characteristics of C,N and P in leaf,litter,and soil（0-20 cm）with P.elliottii×P.oaribaeaas control.【Result】Organic C and total N contents of different Eucalyptus plantations showed the order of leaf〉litter〉soil with significant differences.Total N contents of Eucalyptus plantations in leaf were significantly higher than the control while organic C had opposite results.Total N content of E.torellianainlitter washigher or significantly higher than other Eucalyptus plantations,but was not significantly different from that of P.elliottii×P.oaribaea.Total P content in soil of control was significantly higher than that of the four Eucalyptus plantations.The litter C/N ratios were 39.43-63.35,indicating that litter decomposition rate was low and restricted by N.The soil C/N ratios in 8 years old E.camaldulensis and 10 years old E.pellida were significantly higher than that of 10 years old E.torelliana,15 years old E.urophyllaand P.elliottii×P.oaribaea,demonstrating that older plantations soil had faster nitrogen mineralization rate.The correlation analysis showed that the C,N and P in ecosystem realized transportation and transformation among plants,litter and soil.【Conclusion】The litter decomposition rates of Eucalyptus plantations and P.elliottii×P.oaribaeaon the Leizhou Peninsula were slow and restricted by N element.Compared to the four Eucalyptus plantations,P.elliottii×P.oaribaea had better nutrient utilization efficiency and carbon sequestration capacity.Different Eucalyptus types and P.elliottii×P.oaribaea had different growth restrictive elements.Therefore,balanced fertilization was needed to prevent soil degradation in these fastgrowing pine and Eucalyptus plantations.
作者
许宇星
王志超
竹万宽
杜阿朋
XU Yuxing,WANG Zhichao,ZHU Wankuan,DU Apeng(China Eucalypt Research Centre, Zhanjiang , Guangdong 524022, Chin)
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2018年第3期94-100,110,共8页
Journal of Northwest A&F University(Natural Science Edition)
基金
"十三五"国家重点研发计划课题(2016YFD0600505)
广东省林业科技创新项目(2014KJCX021-04
2013KJCX014-03)
广东湛江桉树林生态系统国家定位观测研究站项目(2016-LYPT-DW-126)
关键词
桉树
湿加松
生活叶
凋落物
土壤
化学计量特征
Eucalyptus
P.elliottii×P.oaribae
leaf
litter
soil
stoichiometry characteristics
作者简介
许宇星（1987-），男，山西大同人，工程师，主要从事桉树可持续经营研究。Email：wsxyx1987@163．com;[通信作者]杜阿朋（1979-），男，河北定州人，副研究员，博士，主要从事桉树林生态研究。Email：dapzj@163．com
