Wu Jian, Sha Chen Yan, Wang Min, Wu Jian Qiang, Tan Juan, Qi Xiao Bao, Huang Shen Fa
Shanghai Academy of Environmental Sciences, Shanghai 200233, China.
College of Ecological and Environmental Science, East China Normal University, Shanghai 200062, China.
Ying Yong Sheng Tai Xue Bao. 2017 Jul 18;28(7):2231-2238. doi: 10.13287/j.1001-9332.201707.004.
Plant-soil carbon stable isotope characteristics of riparian herbaceous ecosystem were ana-lyzed by measuring the δC value of plant tissues from four typical riparian herbaceous plants, which were Cynodon dactylon, Trifolium repens, Festuca arundinacea and Imperata cylindrical, and that of soil organic carbon (SOC) from different vertical depths along Dongfeng Port River in Qingpu District, Shanghai. The result showed that T. repens and F. arundinacea were C3 plants while C. dactylon and I. cylindrical were C4 plants. There was no significant difference between the δC va-lue of stem and leaf, litter and root of the four herbaceous plants. The surface SOC δC value of C3 and C4 plants strips showed different trends with soil depth, which could be related to the background SOC δC value, soil carbon stable isotope fractionation effect and plant root distribution depth as well. Plant input was the main source of SOC and the δC composition of plant organisms had direct effect on the SOC δC value. The δC value of plant components were significantly correlated with the δC value of SOC. The SOC content and δC value were significantly correlated in the four herbaceous plants strips. The SOC content and δC value showed linear negative correlation in C3 plant strips and linear positive correlation in C4 plant strips.
通过测定上海青浦区东风港河沿岸4种典型河岸草本植物（狗牙根、白三叶、高羊茅和白茅）的植物组织δC值以及不同垂直深度土壤有机碳（SOC）的δC值，分析了河岸草本生态系统的植物-土壤碳稳定同位素特征。结果表明，白三叶和高羊茅为C3植物，而狗牙根和白茅为C4植物。4种草本植物的茎、叶、凋落物和根的δC值之间无显著差异。C3和C4植物条带的表层SOC δC值随土壤深度呈现不同趋势，这可能与SOC δC背景值、土壤碳稳定同位素分馏效应以及植物根系分布深度有关。植物输入是SOC的主要来源，植物有机体的δC组成对SOC δC值有直接影响。植物各组分的δC值与SOC的δC值显著相关。4种草本植物条带的SOC含量与δC值显著相关。在C3植物条带中，SOC含量与δC值呈线性负相关，在C4植物条带中呈线性正相关。
