河北坝上草地群落季节动态的定位研究

Site Investigation on the Seasonal Dynamic of Grassland Association in Hebei Highland

１９８６年５～１０月在河北省坝上草地，从牧草返青至枯黄一个完整的生长周期里，对２个人工草地、３个天然草地的样地定期测试了地上生物量、叶面积指数和叶绿素的季节动态。结果表明，该年牧草和草地群落的生长发育模式的趋势为双峰式，前低后高；第一次峰出现在７月末８月初，第二次峰出现在８月末９月初；活的地上生物现存量的最大值为老芒麦草地２６１．０ｇ／ｍ２，丘间平地贝加尔针茅＋羊草草甸草原３２４．

The seasonal dynamic of above ground biomass, leaf area index and chlorophyll contents were regularly investigated on two artificial and three natural grassland from green turning to withering and yellow in Hebei Highland from May to October in 1986.The result shows the pattern of growth have two peaks,the formal is higher and appears in the end of July to the beginning of August; the latter is lower and appears in the end of August to the beginning of September;the maximum value of above ground biomassbelongsto the artificial grassland ( Elyms sibiricus ) with 261.0 g/m 2,the natural grassland ( Stipa baicalensis + Leymus chinensis ) with 324.2 g/m 2.