干旱区旱生芦苇根系分布及土壤水分动态

根据2003-2006年实测的旱生芦苇地的土壤水分资料和芦苇根系资料,对旱生芦苇的土壤水分时空变化特征及产生变化的原因进行了分析。结果表明,1)旱生芦苇根系深度达250 cm以上,毛细根分布最多区域在0~30cm土层,30~210 cm土层芦苇毛细根重密度呈现波动起伏,210 cm深度以下逐渐减小。2)2003-2006年芦苇地土壤水分年际间变化较为复杂,不同的生长阶段年际变化特征不同。3)每年的芦苇生长期(4-10月)内,土壤水分呈现"降-升-稳定-降-稳定"的变化规律。4)芦苇地土壤水分垂直变化特点是,0~200 cm土壤水分变化较为活跃,200 cm深度以下土壤水分变化较为稳定。

Study on the root distribution and soil water dynamics under Phragmites arid area

Based on soil water content and root measurements of Phragmites in 2003-2006,this paper analyzed the characteristics of soil water content changes in time and space and discussed the reasons for these changes.The results showed that: 1) The Phragmites root can reach a depth of more than 250 cm,the area of the largest weight density of Phragmites root is the upper(<30 cm) soil surface,and the weight density has a fluctuation down to 210 cm,and deeper than 210 cm the weight density is gradually reduced.2) The year-to-year change of Phragmites soil water was very complex,and there were different changing characteristics at different growth stages.3) In the Phragmites growth period(Apr.-Oct.) each year,soil water content had a regular "fall-stable-fall-stable" pattern.4) Soil water content actively changed in the 0-200 cm depth but was stable at depths lower than 200 cm.