松嫩平原羊草草甸草原主要植物种群能量积累和分配

在松嫩平原羊草草甸草原，羊草、拂子茅、碱茅和虎尾草各器官热值的季节变化呈波动型，但总的规律是穗＞叶＞茎＞立枯体．4种植物种群地上部能量现存量的季节变化均呈单峰曲线，能量积累量为羊草＞拂子茅＞虎尾草＞碱茅．能量增长率一般呈双峰曲线，第一次峰值出现在抽穗期，第二次在种子成熟期，生长末期出现负值．地上部能量的水平分布规律，不同生育期在各器官中的分配比率不同．4种植物种群能量的垂直分布规律相似，即地上部能量的垂直空间分配格局基本上呈塔形，最大值出现在10-30cm空间内．地下部能量垂直结构由地表至土壤深层呈典型的倒塔形，最大值在0-10cm层．地下部的能量现存量约为地上部的3-4倍。

Energy accumulation and allocation of main plant populations in Aneurolepidium chinense grassland in Songnen Plain

The calorific value of plants is dependent on their biological characteristics and energy-containing materials. The allocation of calorific value in different organs of Aneurolepidium chinese, Calamagrostic epigejos, Puccinellia tenuiflora and Chloris virgata was inflorescence > leaf > stem > dead standing. The seasonal dynamics of standing crop energy of aboveground part of four plant populations showed single-peak curve, and the energy production was Aneurolepidium chinense > Calamagrostic epigejos > Chloris virgata > Puccinellia tenuiflora. Energy increasing rate showed double-peak curve, with the first peak at heading stage and the second peak at maturing stage of seeds. Energy increasing rate was negative at the final stage of growth. The horizontal distribution of energy of aboveground part was that the allocation ratio of different organs at different growth stages was different. There existed a similar trend for vertical distribution of energy among four plant populations, i.e., was the vertical distribution of energy of aboveground part showed a tower shape, with the maximum value in 10-30 cm height. The vertical distribution of energy of underground part showed an inverted tower shape from soil surface to deeper layer, with the maximum value in 0-10 cm depth. The standing crop energy of underground part was about 3-4 times than that of aboveground part.