科尔沁沙地15种禾本科植物种子萌发特性比较

在实验室条件下，观测了科尔沁沙地乌兰敖都地区禾本科植物当年新采种子的萌发特点．15种植物中，披碱草、糙隐子草、冠芒草、大油芒、芦苇、虎尾草、野古草、狼尾草的发芽率超过80％，水稗草、牛鞭草、虱子草、狗尾草的发芽率不足10％．1～3d开始发芽的植物有大油芒、画眉、芦苇、虎尾草、披碱草、冠芒草、毛马唐、糙隐子草．超过10d基本不发芽的植物包括狗尾草、虱子草、牛鞭草．发芽持续期小于10d的植物包括毛马唐、水稗草、芦苇、画眉草、大油芒；发芽持续期21～30d的植物有披碱草、冠芒草．发芽种子超过总发芽种子的50％需要天数为虎尾草2d，芦苇3d，大油芒4d，披碱草5d，糙隐子草5d，野古草7d，冠芒草7d，狼尾草10d．与英国Sheffield地区相比，乌兰敖都地区一年生禾草发芽率低的所占比重更大，发芽更为缓慢；乌兰敖都地区多年生禾草的发芽率差别很小，但发芽更为缓慢．杂草植物萌发的风险分摊能力相对明显，因此抗干扰能力相对较强．

A comparative study on seed germination of 15 grass species in Keeqin Sandyland

A laboratory study was made on the germination characteristics of freshly-collected seeds of grass species at the Wulanaodu area of Keeqin Sandyland in Eastern Inner-Mongolia.Of the 15 species examined, 8 species including Clinelymus dahuricus,Cleistogenes squarrosa,Pappophorum boreale,Spodiopogon sibiricus, Phragmites communis, Chloris virgata, Arundinella hirta, Pennisetum alopecuroides had a germination rate of over 80 % , but 4 species including Echinochloa hispidula .Hemarthria compressa, Tragus berteronianus and Se-taria viridis had a value of less than 10% . Spodiopogon sibiricus, Eragrostis pilosa, Phragmites communis, Chloris virgata, Clinelymus dahuricus, Pappophorurn boreale, Digitaria cilliaris and Cleistogenes squrrosa began to germinate within 1 ~3 days after the test began, while Setaria viridis, Tragus berteronianus and Hemarthria compressa failed to germinate in a period of more than 10 days. For the species such as Digitaria cilliaris, Echinochloa hispidula, Phragmites communis, Eragrostis pilosa and Spodiopogon sibiricus, their germination period was less than 10 days, while Clinelymus dahuricus and Pappophorum boreale had a germination period of more than 20 days. The days required for half the final germination rate to be reached were; 2 days for Chloris virgata, 3 days for Phragmites communis, 4 days for Spodiopogon sibiricus, 5 days for Clinelymus dahuricus and Cleistogenes squarrosa, 7 days for Arundinella hirta and Pappophorum boreale, and 10 days for Pennisetum alopecuriodes . Compared with the Sheffield region in Britain, the Wulanaodu area of Kerqin Sandyland had a higher proportion of annual grasses with a low germination rate and a longer germination period, and the perennial grasses at the Wulanaodu area had an approximately same germination rate, but a longer germination period. During germination,ruderals showed the potential for risk-sharring, and thus, they had a relatively higher disturbance-resistance capacity.