适于深圳城市河道护坡的草类植物筛选

通过构建模拟城市河道,测定7种供试植物的盖度、生物量、坡面适应性、根系特征、耐淹能力及抗冲刷能力等,对适于深圳城市河道护坡的草类植物进行了筛选.结果表明:在深圳的自然条件下,各供试植物在模拟河道堤坡上都能正常生长;播种或幼苗移栽4个月后,各物种间的盖度、生物量、根系特征、耐淹能力及抗冲刷能力差异显著;百喜草盖度可达70%以上,生物量(干重)可达8.33 kg/m2,其中根系生物量为2.09 kg/m2,而且直径不超过1mm的有效根多,明显高于其它供试植物;百喜草植株在部分淹水、全淹时半数死亡时间分别为45及15 d,耐淹能力强;百喜草砌块能抵御4.0m/s的流速冲刷.综合各项指标,百喜草是最适于深圳地区城市河道护坡的优良水保草种.

Screening of Grasses for Slope Protection of Urban Rivers in Shenzhen City

Suitable grasses for the slope protection of urban rivers in Shenzhen city were screened from 7 species in a simulated urban river.In the investigation,the indexes such as covering rate,biomass,slope adaptability,root characteristics,submergence tolerance and erosion resistance of the grasses were compared.The results show that all the 7 species can grow in the embankments along the simulated urban river,and that there are significant diffe-rences in the above-mentioned indexes of the cultivars after 4 months of cultivation.It is also demonstrated that P.notatum is a desirable species due to its highest covering rate(70%),greatest biomass(8.33 kg/m2 in dry weight) and root biomass(2.09 kg/m2) and the most effective roots with a diameter of less than 1 mm.Furthermore,P.notatum is of the best submergence tolerance and its half lethal time under partial and full drowned conditions is up to 45 d and 15 d,respectively.The block of P.notatum is also found to be resistant to an erosive velocity of 4.0 m/s.By considering all the above-mentioned statements,it is thus concluded that P.notatum is the most suitable for the slope protection of urban rivers in Shenzhen city.