Abstract: In this study,pasture of two households in Oula town,maqu county of Gansu province was taken as the experimental area,the aboveground biomass,main nutrients and dry matter digestibility of forage were studied. Main results were as follows:The average aboveground biomass of the alpine meadow (3.27 t·hm^-2) and CP content (9.22%) were significantly higher,and contents of ADF and NDF were significantly lower than that of marshy meadow,respectively. Therefore,alpine meadow had high productivity and nutrition. For two types of pasture,the average aboveground biomass was the lowest in April (1.32 t·hm^-2),it increased from April to August,and the highest value was obtained in August (4.41 t·hm^-2). For the same month,alpine meadow owned high contents of CP and Ash;In contrast,contents of ADF and NDF were significantly increased from March to April and from May to October,and decreased from April to May,and for the same month,alpine meadow had lower contents of ADF and NDF than that of marshy meadow. In this experiment,the change tendency of the aboveground biomass and nutrition quality in the alpine pastoral area of Qinghai Tibet were studied,it would help people to understand the relationship between the livestock and forage and provide theory basis for the supplement in this area.

Key words: Qinghai-Tibet plateau, Aboveground biomass, Nutrient, Digestibility of dry matter (DMD), Change tendency

摘要： 本试验以甘肃省玛曲县欧拉乡2个项目户的天然草地为试验对象,研究了青藏高寒牧区高寒草甸和沼泽化草甸地上生物量、主要营养成分及干物质消化率间的差异以及年际和月际变化规律。结果表明:高寒草甸的平均地上生物量(3.27t·hm^-2)和粗蛋白含量(9.22%)显著高于沼泽化草甸,酸性洗涤纤维含量极显著低于沼泽化草甸,中性洗涤纤维含量显著低于沼泽化草甸,其营养成分优于沼泽化草甸;高寒草甸和沼泽化草甸4月份的平均地上生物量最低(1.32 t·hm^-2),4—8月份显著增加,8月份最高(4.41 t·hm^-2);同一月份高寒草甸的中性和酸性洗涤纤维含量均低于沼泽化草甸。本试验通过研究青藏高寒牧区天然草地生物量和营养成分的变化,有助于理解该区的草畜关系,可以为家畜补饲提供理论基础。

关键词: 青藏高寒牧区, 地上生物量, 营养成分, 干物质消化率, 变化动态