白刺幼苗生物量与氮含量在叶与全株间的尺度转换

Scaling from leaf to whole plant in biomass and nitrogen content of Nitraria tangutorum seedlings

【目的】植物生物量和营养的分配模式是植物对生态系统中物质和能量循环的一种演变策略,其资源分配给不同构件的模式是其生物学特性的一个基本方面。本文目的为解决野外调查工作中植物整体生物量与养分含量难以测定等问题。【方法】以乌兰布和沙漠东北部唐古特白刺幼苗为研究对象,将其分为根、茎、叶3个主要组成部分,通过对这3个主要组成构件生物量的测定与拟合分析,以叶器官为变量,建立了白刺全株生物量的预测模型,并通过进一步测定其各部位氮含量,建立了其全株氮含量的预测模型,得出了白刺叶与全株不同尺度之间生物量与氮含量的缩放关系,探讨了白刺全株生物量与全株氮含量之间的相关关系。【结果】结果表明:以叶生物量对数转换值为自变量能够很好的拟合出根(R^2=0.901 2,P<0.001)和茎(R^2=0.926 4,P<0.001)的生物量;以叶氮含量为自变量也能够较好的拟合出根(R^2=0.850 1,P<0.001)和茎(R^2=0.844 7,P<0.001)的氮含量,进而得出以叶器官生物量为自变量的全株生物量预测模型:M_p=M_L+10^(0.020 9)M_L^(0.845 6)+10^(0.436 9)M_L^(0.867 8),以及以叶器官生物量与氮含量为自变量的全株氮含量预测模型:N_p=M_LN_L+10^(0.020 9)M_L^(0.845 6)(0.109 4N_L+0.015 6)+10^(0.436 9)M_L^(0.867 8)(0.108 8N_L+0.014 8),并经实测数据验证,白刺全株生物量与全株氮含量之间的相关关系可表达为:lgN'p=1.075 2lg M'p-1.768 4。【结论】白刺通过某一构件的生物量与氮含量能够较好的预测出其全株生物量与全株氮含量之间的相关关系。

[Objective]The relationship between the evolved strategies of plant species and the material and energy cycles of ecosystems is linked by plant biomass and nutrient allocation,and the pattern of plant resources allocated to its different components is a fundamental aspect of its biological characteristics.In this paper,the scaling from components to whole plant in biomass and nitrogen content of Nitraria tangutorum seedlings was researched in the northeast of Ulan Buh Desert,Inner Mongolia of northern China.[Method]Firstly,we measured the biomass of root,stem and leaf of Nitrariatangutorum,individually,and we converted them into a value of logarithm（base 10） to get the linear fitting equation of the stem biomass or root biomass taking leaf biomass as variable.Then we measured the nitrogen concentration of each component,also,we linearly fitted the nitrogen concentration of the leaf and the stem or root for further study.[Result]The results showed that the biomass of stem and root could be predicted accurately by giving the leaf biomass（R^2 of root-leaf and stem-leaf regression equations were 0.901 2 and 0.926 4,respectively）.And the nitrogen concentration of root and stem also could be predicated well by giving the leaf nitrogen concentration too（R^2 of root-leaf and stem-leaf regression equations was 0.850 1 and 0.844 7,respectively）.Then we obtained the prediction model of the whole plant biomass by adding the three parts of plant：M_p=M_L＋10^（0.020 9） M_L^（0.845 6）＋10^（0.436 9）M_L^（0.867 8）,and we inferred the nitrogen content predicting model of whole plant by adding the three parts together similarly：N_p=M_LN_L＋10^（0.020 9）M_L^（0.845 6）（0.109 4N_L＋0.015 6）＋10^（0.436 9）M_L^（0.867 8）（0.108 8N_L＋0.014 8）.And through the field data verifying,it was showed that the relationship between the biomass and nitrogen content of whole plant could be predicted by the biomass and nitrogen concentration of Nitraria tangutorum leaves：lg N＇p=1.075 2 lg M＇p-1.768 4.[Conclusion]It was showed that the biomass and nitrogen content of the whole plant of Nitraria tangutorum can be predicted by its components.