固沙先锋植物沙米的生物学特征研究

以石羊河下游荒漠区的古浪明沙咀和民勤西沙窝为研究区,研究了沙米的形态结构特征、种子形态及其萌发特性等,结果表明:沙米植株冠幅大小、第1层侧枝数、根径、根深、根幅和最大根长与株高呈线性正相关关系;地上生物量、地下生物量和总生物量与株高呈二次曲线关系,达到显著正相关;沙米生物量中地上生物量占到绝大部分,地上部分生物量中以10～20 cm生物总量最大,各层生物量逐渐减少;沙米种子的大小、千粒质量、种子含水率在不同生态区域或不同年份之间差异显著;沙米种子自然萌发率不高,在黑暗条件下,可提高其发芽率。

Study on Biological Characters of Agriophyllum spuarrosnm, A Pioneer Plant for Sand Control

The Mingshazui of Gulang county,and the Xishawo of Minqin county,both are in the lower reaches of the Shiyang River,were selected as research sites.The researches on the morphology,seed form and germina-tion of Agriophyllum squarrosum were conducted.The results showed that the canopy,root depth,root volume,length of the largest root of A.squarrosum all were increasing with its height,and were highly correlated positively with its height.There was a significant positive conic correlationship between the above-ground biomass,under ground biomass,and total biomass and its height respectively.As to the biomass above ground,the biomass the height of 10~20 cm above ground was the greatest,and decreasing from low part up to top.As to the biomass for different organs,the biomass for roots was the smallest,and the biomass for fruits was the greatest.The variance of the size,the 1 000 kernel weight and moisture content of air-dried seeds for different ecological regions or differ-ent years was extremely significant.The natural germination rate of A.squarrosum was not high,and was suitable in darkness.