麻疯树群体构件特征资源依赖性研究

The Dependency of Module Characteristics of the Jatropha curcas Population on Resources

本文首次以克隆木本植物构件的概念,研究了非克隆木本植物构件对资源环境的依赖性问题。在金沙江干热河谷攀枝花段,研究了生物柴油植物麻疯树群体构件对资源性因素光照、水分和养分的适应性反应。养分资源(土壤厚度为60 cm以上、20 cm和40 cm)不同时,构件直径、长度、长径比、叶片数量、叶片密度、头茬果实数量和生殖频率等参数都存在极显著差异,在养分资源充足时群体构件参数明显较大。与林外相比,乔木林下麻疯树林分构件直径、长度、长径比在花期呈现出显著差异,而在果期差异微弱,叶片数量、叶片密度、生殖频率却没有出现差异,而头茬果实产量差异极为明显。土壤水分对构件长度、长径比、叶片数量和生殖频率影响较大,而对构件直径和叶密度影响不显著,而对头茬果实数量的影响较为微弱。暗示资源性因素光照、水分和养分是构件光合作用所需要的基础资源,群体构件特征对资源性因素存在明显的适应反应,均反映了群体构件特征对资源性因素的依赖性。本文分析构件特征对资源性因素影响时,没有考虑密度效应和海拔问题。在理论上,非克隆木本植物构件麻疯树与克隆木本植物竹类的克隆分株一致,统一了木本植物中的构件概念,在研究中与组件性构件相区分。麻疯树萌生现象较为明显,是适应干热河谷季节性干旱环境的一种策略。在生产上,需要优化资源性因素的配置,在保证光照强度的条件下,通过增加土壤厚度,和/或人工增加养分元素来促进构件发育与生殖,来实现麻疯树生物柴油供应原料的高产与稳产。未来研究中,需要关注构件分支状况与资源性因素梯度的关系,探讨构件对资源性因素的适应对策,深入揭示构件的发生、发展与适应机制。

In this paper,studies were firstly made of the dependency of non-clone plant community modules on resource environments,applying the module concept of clonal woody plants（such as bamboo）.In the Panzhihua section of the Jinsha River watershed,researches were conducted on the adaptation response of Jatropha curcas population modules to resource factors such as difference of light,moisture and niutrition element content.With a difference of nutrition elements（in a 20 cm,40 cm and 60 cm-depth soil respectively）,there was an extremely obvious difference in these parameters,such as diameter,length,ratio of length and diameter,quantity of leaves,leaf density,fruit quantity of first rotation,and reproductive frequency of modules,which demenstrated that the components of module were bigger in the full condition of nutrition elements.Compared to Luoguo bridge community without the canopy of Eucalyptus spp.and Delonix regia,the diameter,length,and ratio of length and diameter of population module with the arbor canopy had extremely evident diferences in flowering time（although with a slight difference in fruiting time,p=0.075）,but no obvious differences in leaf quantity,leaf density and reproductive frequency with a excpetion of fruit production of the first rotation.Soil moisture had a siginificant influence on population module features in the Madianhe plot,although no influence in some parameters（such as module diameter and leaf density） and a slight difference for fruit quantity of the first rotation.These results demonstrated that light,moisture and nutrition elements were the elemetary resources that photosynthesis needed,and population module characteristics had obvious adaptaion response to resource factors,implying the dependency of these module features on resource environments.In this paper,no consideration was given on problems of density effect and hot factors when these responses were analysized.Theoreticaly,the modules of Jatropha cascus,a tree of non-clone woody plants（including leaves,branches,flowers and fruits,and roots）,was consistent with clonal woody plants（snch as bamboos）,which integrated the module concept of the woody plant and distinguished with the concept of organ in the study.The obvious sprouting phenomenon was founded in Jatropha curcas L.,which was a strategy adapting to the seasonal dry environment of the dry-hot valleys.Practically,the higher and stabler production of J.curcas biodiesiel seed provision required increasing the soil depth and fertilizer to induce the development and reproduction of population modules.In the future study,the relationship of population module architecture and resource environment gradient should loe considered,the discussion should be made on the strategy of population modules adapted to resource environment,thus deeply elucidating the occurrence,development and adaptation mechanism of population modules.