Abstract: [Objective] This study aims to explore the monthly dynamic changes and nutritional value of the three important grassland types in Xinjiang Shaertao Mountain and comprehensively rank the nutritive content of the three important grassland types (Stipa capillata + Achnatherum splendens, Iris ruthenica + Gramineae, Dactylis glomerata + herabarum varianum).[Method]The international standard method was used to measure the content of nutrients in the grass groups.The data were processed by SPSS 17, Duncan and membership function analysis.[Result]The result showed that the content of crude protein, calcium, phosphorus and total gross energy gradually reduced with the increase of month, while the content of acid detergent fiber and neutral detergent fiber tended to be increased.The order of comprehensive nutritive value during growth was May>June>July>August>September>October>November.The comprehensive nutritive value evaluation of different grassland types of vegetation was the third type(Dactylis glomerata+herabarum varianum), the second type(Iris ruthenica+Gramineae), the first type(Stipa capillata + Achnatherum splendens), respectively, in May and June.And from July to November, it was the second type, the third type, the first type, respectively.[Conclusion]According to the seasonal characters, the 3 important grass groups in the natural grassland in Xinjiang Shaertao Mountain in June and July have better utilization value.

摘要： [目的]研究新疆沙尔套山天然草地3个重要型草群营养物质的月动态变化与营养价值,对不同月季的3个重要草地型草群(针茅+芨芨草型、紫花鸢尾+禾草型、鸭茅+杂类草型)的营养成分(粗蛋白质、粗纤维、酸性洗涤纤维、中性洗涤纤维、粗灰分、钙、磷、总能)进行测定与分析和评价.[方法]采用国标法测定草群营养成分含量;运用SPSS 17.0、Duncan法及隶属函数分析法对数据进行处理.[结果]粗蛋白质、钙、磷、总能含量随着月份递增而下降,酸性洗涤纤维、中性洗涤纤维含量逐渐增高.营养价值评定按生长期综合排序为:5月>6月>7月>8月>9月>10月>11月.按不同草地型草群评定结果进行排序,其中5、6月的营养价值排序为:3型(针茅+芨芨草型)>2型(紫花鸢尾+禾草型)>1型(鸭茅+杂类草型);7、8、9、10、11月的营养价值排序均为:2型>3型>1型.[结论]新疆沙尔套山天然草地3个重要型草群在7、8月份具有较好的利用价值.