Abstract: Four sites that depend on different altitudes along northern slop of Daban Mountain were used to investigate the impacts of altitude of sites herbage grow on gramineous herbage vitro digestibility, Every 200m of each site were choosed from 3200m to 3800m.Three species of Tibetan Plateau gramineous herbage, such as Festuca ovina,poa annua,Koeleria cristata,which grown at different altitudes of Daban Mountain were selected to determine vitro digestibility, The results obtanied from the experiment indicate that there are a positive correlation between herbage vitro digestibility and the altitude of sites herbage grow.based on the results of 1999 and 2000 vitro digestibility of Festuca ovina,Poa annua,Koeleria cristata increase 6.42 and 6.35,8.69 and 4.89, 9.8 and 5.1 percent respectively as raise of altutude from 3200m to 3800m.

Key words: Daban Mountain, altitude, Festuca ovina, Poa annua, Koeleria cristata, Vitro digestibility

摘要： 利用大板山北坡3200m-3800m的海拔梯度,分别在3200m、3400m、3600m和3800m处选取羊茅、一年生早熟禾和(艹洽)草用二级离体培养法测定其体外消化率。1999和2000年测定结果表明,随着海拔的升高,3种牧草的体外消化率呈增加趋势,海拔从3200m升到3800m,羊茅、早熟禾、(艹洽)草的体外消化率分别增加6.42、6.35、8.69和4.89、9.8和5.1个百分点。显著性分析结果表明,供试牧草的体外消化率与其生长的海拔高度之间的正相关关系差异显著(P<0.05)。

关键词: 大板山, 海拔, 羊茅, 早熟禾, 艹洽草, 体外消化率