牦牛放牧强度与小嵩草高寒草甸植物群落的关系
Studies on the Relationship Between Grazing Intensities for Yaks and Plant Groups in Kobrecia Parva Alpine Meadow

董全民 ¹ 赵新全 ¹ 马玉寿 ² 李青云 ² 王启基 ¹ 施建军 ²

文摘	分析牦牛放牧强度对小嵩草（Kobrecia parva）高寒草甸生物量和群落结构的影响。结果表明：优良牧草比例和牦牛个体增重的年度变化呈正相关；在牦牛放牧条件下，优良牧草比例年度变化是评价小嵩草高寒草甸放牧价值的直接度量指标；而相似性系数和草地质量指数的变化与牦牛生产力没有明显的联系，只能指示植物群落整体的相对变化程度；当放牧强度为1．86头／hm^2时，能维持优良牧草比例和牦牛年度增重，是保持小嵩草高寒草甸不退化的适宜放牧强度。
其他语种文摘	The trial was conducted in Dari County of Guoluo Prefecture, Qinghai Province, from 1998 through 1999. According to the usual practice of rotation grazing in Qinghai-Tibet Plateau, the trial area was divided into the warm-season and cold-season grazing pasturelands. Grazing times were five months （June-October） in the warm-season pastureland and 7 months （November-May） in the cold-season one. Each grazing pasture was divided into three paddocks that stocked yaks, and theoretically, 30%, 50%, and 70% of the herbage yield in a year would be consumed in the grazing period. Aboveground biomass of different plant groups and community structures constituted under different grazing intensities had been studied according to the data collected during the two years＇ yak grazing in the Kobrecia parva alpine warm-season pastureland. The results indicate that a positive correlation existed between the rate of desirable forage and the yearly live-weight gain of each yak. By setting up a standard of vegetation change extent, it was determined that the yearly change o{ the rate of desirable forage of a yak-grazing K. parva alpine pastureland was the direct measuring index of its grazing value, while the change of similarity coefficient, and pastureland quality index were not distinctly related to the yak production, and, therefore, did not reflect the change of the grazing value of the pastureland, but merely reflected the extent of relative change of the total plant communities. When grazing intensity reached 1.86 head/hm^2, the pastureland maintained the rate of desirable forage and ensured the yearly live-weight gain of the yaks as well. Consequently, 1.86 heads/hm^2 is considered to be the maximum grazing intensity assuring a lush green K. parva alpine warm-season pastureland.
来源	草地学报 ,2005,13(4):334-338,343 【扩展库】
关键词	小嵩草高寒草甸 ; 放牧强度 ; 优良牧草 ; 地上生物量 ; 植被变化指标
地址	1. 中国科学院西北高原生物研究所, 西宁, 810002 2. 青海省畜牧兽医科学院, 西宁, 810003
语种	中文
文献类型	研究性论文
ISSN	1007-0435
学科	畜牧、动物医学、狩猎、蚕、蜂
基金	青海省“九五”科技攻关项目 ; 国家“十五”科技攻关重大项目
文献收藏号	CSCD:2175121