短生植物重量的动态变化及其分析

通过对阜康站研究区域10种常见短生植物重量的研究表明：1)绝大多数短生植物在其生长发育过程中重量动态变化明显，生长曲线呈单峰型。2)生长初期，多数短生植物株重的增加与株高生长同步。生长后期，株高生长停止，株重先是伴随花果的形成得以增加，果实成熟后则随叶片的脱落迅速下降。3)与长营养期植物相比，在一年生短生植物当中，果实在地上部重量中的比例很高，最高者达77.8%。4)同为短生植物，生长特征存在着较大的差异。据以鲜重、干重、株高、根长和地上、地下重量比例为变量进行的聚类分析结果，可将短生植物分为多年生营养繁殖、多年生种子兼营养繁殖和一年生种子繁殖三大类。

ANALYSIS OF DYNAMICS OF PLANT WEIGHT IN EPHEMERALS

Ephemerals are a group of plants in arid and semi-arid area. By analyzing weight dynamics of 10 species of ephemerals in Fukang Desert Ecosystem Observation and Experiment Station of Xinjiang, The Chinese academy of Sciences in 1991, the following was found out:1. The weight of most ephemerals greatly changed during their growth and development processes. There was hue peak on the growth curves of most ephemerals except for Eremurus anisopteris (Fig. 1).2. The weight of most ephemerals increased rapidly in May. Their weight peaks took place during the middle ten days of July (Table 2).3. The growth characteristics were evidently different among the species of ephemerals. According to the differences the ephemerals could be divided into three types: perennial vegetative propagation type, perennial vegetative and seed propagation type and seed propagation type (Fig. 2, 3).4. The proportion of fruits to the aboveground weight of ephemerals was obviously higher than that of long life cycle herbage (Table 1). The Lowest was 21.5% and thehighest was 77%. 5. Weight dynamics of most ephemerals were closely related to their height and phenological phase (Fig. 1). The shapes of weight and height growth curves were similar during the earlier period of growth and developnent. The weight of most ephemerals increased rapidly in the period of reproduction.