落叶松人工林生态系统净初级生产力形成过程中的能量特征

THE CHARACTERISTICS OF ENERGY IN THE FORMATIVE PROCESS OF NET PRIMARY PRODUCTIVITY OF LARCH ARTIFICIAL FOREST ECOSYSTEM

本文在生物生产力研究的基础之上,通过热值测定,对东北东部帽儿山地区21年生人工落叶松(Larix gmelinii)生态系统净初级生产力形成过程中的能量特征做了系统研究。结果表明:(1)植物热值随植物种类、器官、分布层次、年龄及季节而发生变化。(2)生态系统中活植物体的能量现存量为269.719×10^(10)J/ha,而枯死体中的能量现有量为36.817×10^(10)J/ha,其中凋落物层和立枯体中能量贮量各占84.04％和15.6％。(3)生态系统能量净固定量为264.346×10~9J/ha·yr,其中29.49％的能量存留在植物体中,用于植物净生长。生态系统年能量归还量为88.809×10~9J/ha,其中32.39％的能量在当年被分解释放,余下能量积累于凋落物层之中;生态系统的能量转化效率为2.299％,与其它森林植物群落相比,落叶松人工林系统是高效率的能量代谢系统。

Based on the studies of ecosystem productivity and by means of calormetry measurement,the characteristics of energy in the formative process of net primary productivity of 21 years Dahurian Larch plantion ecosystem was studied systematically on Moer Shan Forest Farm in the eastern part of northeast China. The results showed that (1)Caloric content of plant samples varies with species, organs,ages, distributive layers and seasons. (2) Standing crop energy accumulated in the living plant is 269.719×10^(10) J/ha, while that accumulated in the dead plant is 36.817×10^(10) J/ha, in which 84.04% is in the litter and 15.96% in the standing dead plant. (3) Net energy production of Larch forest ecosystem is 264.346×10~9 J/ha·a, 29.49% of which goesinto the litter in the form of litterfall and the rest retains in the plant for growth. The annual energy return of Larch forest ecosystem is 88.809×10~9 J/ha, with 32.39% from decomposition and rest accumulating in the litter. The energy transformation efficiency of Dahurian Larch plantation ecosystem is 2.299%. Compared to the other plant communitie, Dahurian Larch plantation ecosystem is an energy metobolic system with a high energy conversion efficiency.