毛乌素沙地中国沙棘生长过程与水热条件的关系

The Growth Process of Hippophae rhamnoides ssp. sinensis and the Relationship between Growth Increment and Water-heat in Maowusu Sands

依据定期观测和树干解析资料，采用逻辑斯谛方程和“分段分析”法，探讨了毛乌素沙地中国沙棘的生长特征。结果表明，中国沙棘全年生长历时约１５０ｄ，高峰期出现在５月中旬至７月上旬，其生长过程受制于沙地特殊的气候变化，前期降水和热量不足，后期热量较多、降水稀少且分布不均，天然林中个体的年生过长程明显地区别于人工林，树高速生期到来早，高、径生长具有异速性。这与天然林“过分拥挤”、分株间的“根系连结”及种内自疏密切相关。

Based on the data of periodic growth test and stem analysis ,growth characteristics of Hippophae rhamnoides ssp. sinensis in Maowusu sands were studied by using the methods of Logistic equation and analysis of stages. The results indicated that the growth period was about 150d in a year, the prosperous stage of growth appeared from the middle of May to the beginning of July. And the process of growth was affected closely by special fluctuation in climate, such as shortage of rainfall and heat at pre-stage, the scarce with uneven distribution of rainfall at post -stage. The rapid period of annual growth in height for an individual in natural forest appeared earlier than that in artificial one, meanwhile the period in height and in diameter appeared at different ages. The causes were closely correlated with “overcrowded”, “root connection” and intra-specific thining.