不同草种混播组合在公路边坡的建植效果研究

Effect of different grass species combination on highway slope protection

在青海省高速公路边坡进行不同牧草与灌木混播试验,结果表明,出苗最快的为苜蓿+扁穗冰草,盖度增加也最快,到2005年9月盖度已达70%,赖草+柠条组合盖度变化较大,从2005年的5%增加到次年的90%,且生物多样性最大,群落稳定性最强。地上植物量(干重)增加最快的组合为扁穗冰草+星星草+沙棘,从2005年9月的40 g/m2增加到2006年10月的1200 g/m2。在短期内,适宜当地阴坡种植的优良组合为扁穗冰草+星星草+沙棘,阳坡为苜蓿+扁穗冰草,不同混播组合的建植效果排序如下:扁穗冰草+星星草+沙棘>苜蓿+扁穗冰草>柠条+赖草>其他。

Among the combination treatments,Agropyron cristatum ＋Medicago sativawas the best for seedling speed and coverage increasing （achieved 70% in September2005）. The coverage of Caragana korshin- skii ＋Leymus secalinus, greatly varied and increased from 5% in 2005 to 90% in 2006, and the plant biodiversity index was also the highest. The best combination for aboveground biomass （dry weight base） increasing speed was Agropyron cristatum ＋ Puccinellla tenul flora ＋ Hippophae rhamnoides and it increased from 40 g/m^2 in September 2005 to 1 200 g/m^2 in October 2006. The proper combination on north facing slope was Agropyron cristatum ＋ Puccinellia tenui flora ＋ Hippophae rhamnoides and the combination of Agropyron cristatum＋Medicago sativawas the best on the south-facing slope. The performance order of different combinations was as follows： Agropyron cristatum ＋ Puccinellia tenui flora ＋ Hippophae rhamnoides〉 Agropyron cristatum ＋ Medicago sativa 〉 Cara gana Korshinskii ＋ Leymus secalinus 〉 the rest.