植物生态学报 ›› 2010, Vol. 34 ›› Issue (5): 498-504.DOI: 10.3773/j.issn.1005-264x.2010.05.003

• 研究论文 • 上一篇    下一篇

冬小麦生境中土壤养分对凋落物碳氮释放的影响

申艳1,2, 杨慧玲1, 何维明2,*()   

  1. 1河南农业大学生命科学学院, 郑州 450002
    2中国科学院植物研究所植被与环境变化国家重点实验室, 北京 100093
  • 收稿日期:2009-11-11 接受日期:2010-04-08 出版日期:2010-11-11 发布日期:2010-05-01
  • 通讯作者: 何维明
  • 作者简介:* E-mail: weiminghe@ibcas.ac.cn

Nutrient availability in habitats affects carbon and nitrogen releases of litter in winter wheat

SHEN Yan1,2, YANG Hui-Ling1, HE Wei-Ming2,*()   

  1. 1School of Life Science, Henan Agriculture University, Zhengzhou 450002, China
    2State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
  • Received:2009-11-11 Accepted:2010-04-08 Online:2010-11-11 Published:2010-05-01
  • Contact: HE Wei-Ming

摘要:

土壤养分影响植物生长, 进而影响凋落物质量和产量; 凋落物质量和产量影响凋落物分解过程。基于一个生长实验和一个相同环境分解实验, 研究了冬小麦(Triticum aestivum)生境中养分可利用性对凋落物碳(C)和氮(N)释放的影响。结果显示: (1)冬小麦凋落物产量、叶/根C:N比、C释放量和N释放量随土壤养分梯度呈单调变化; (2)土壤养分影响叶凋落物丢失率而不影响根凋落物丢失率; (3)初始叶/根C:N比与其C、N释放量之间存在负相关关系; (4)分解过程降低叶C:N比和根C:N比。结果表明: 生境中土壤养分的提高可加速凋落物C、N归还, 这反过来可能促进冬小麦生长, 因此这种效应是正反馈; 初始C:N比可预测凋落物C、N释放量。

关键词: C:N比, 碳氮归还, 凋落物分解, 土壤养分可利用性, 冬小麦

Abstract:

Aims Our objective is to test whether C and N releases in winter wheat (Triticum aestivum) litter change monotonically or unimodally with soil nutrients in its habitats.

Methods We conducted a growth experiment where winter wheat was subjected to 6-level nutrient regimes and a common garden decomposition experiment. We determined initial C:N ratios of live tissues, biomass loss of litters, C:N ratios of remaining litter, and the amounts of C and N releases. We analyzed correlations between initial C:N ratios and C/N release or between C:N ratios. All data were analyzed with SPSS 13.0 and R 2.9.1.

Important findings Litterfall, initial leaf/root C:N ratios, C:N ratios of remaining litter, and C and N releases changed monotonically along a soil nutrient gradient. Soil nutrients had significant effects on biomass loss of leaves, but not of roots. There were negative correlations between initial leaf/root C:N ratios and C and N releases. Initial leaf/root C:N ratios were strongly and positively correlated with C:N ratios of remaining litter. These findings suggest that (1) increased soil nutrients surrounding winter wheat plants enhance C and N return in litter, thereby being beneficial to its growth, (2) C:N ratios indicate the potential amounts of C and N releases, and (3) decomposition processes decrease C:N ratios in remaining litter.

Key words: C:N ratio, C and N return, litter decomposition, soil nutrient availability, Triticum aestivum