岩生植物金发草生长特征研究

研究了重庆地区金发草在3种基质5种生境中的生长特征.结果表明，5种生境下金发草基径、冠幅、高度及根系面积、最长根和根深差异极显著.3种基质中，紫色土中金发草的地上部分基径(15.18 cm)、冠幅(3 086.77 cm2)和高度(66.58 cm)均为最大值，而紫色砂岩金发草的基径(10.89 cm)、冠幅(1 868.79 cm2)和高度(60.75 cm)均为最小值，但差异不显著.砂岩中金发草的根系比紫色土中分布广泛，差异显著，说明岩石生境中金发草将较多生物量投入到根系，通过增加根系的生长，提高其在岩石上的固着能力，扩大根系吸收面积，忍耐岩石基质的干燥和贫瘠.

Growth characteristics of rock plant Pogonatherum paniceum

The study on the growth characters,above and underground biomass,and root-shoot ratio of Pogonatherum paniceum grown on three types of substrates and five types of habitats in Chongqing showed that there were significant differences in plant growth characters,including stalk basal diameter,plant canopy and height,root system area and depth,and maximum root length among five habitats.For shoot growth,though the plants grown on purple soil had the maximum stalk basal diameter (15.18 cm),canopy (3 086.77 cm~2) and height (6.58 cm) while those grown on purple sandy rock had the minimum values (stalk basal diameter 10.89 cm,canopy (1 868.79) cm~2,and height 60.75 cm).There were no significant differences among three types of substrates.As for root system,there were significant differences between sandy rocks and purple soil,the plants grown on sandy rocks having higher means of root system area (1 389.14 cm~2 and 1 487.14 cm~2) and maximum root length (45.83 cm and 39.24 cm) than those grown on purple soil (root system area 717.09 cm~2,maximum root length 21.42 cm).The plants grown on sandy rock allocated more biomass to root system,and had higher root-shoot ratio,which was helpful for its fixation on rock and its endurance on the desiccation and arid of rock substrate.