【摘要】 用3阶多项式生长曲线数学模型拟合牧草产量各状况年的牧草生产力,与实际值吻合较好。模拟结果表明,最大生长率70.2 kg/hm2.d,最小生长率1.6 kg/hm2.d;月最大产量2 042.5 kg/hm2,月最小产量57.6 kg/hm2。生长季5~9月,旬≥0℃的累积积温每增加1℃,最高状况年比最低状况年每旬增加干物重2.54 kg/hm2;旬累积降水量每增加1 mm,最高状况年比最低状况年每旬增加干物重7.33 kg/hm2;旬累积日照时数每增加1 h,最高状况年比最低状况年每旬增加干物重3.83 kg/hm2。考虑到倾向率变化的不同,旬累积降水量引起的产量变化是主要原因,旬累积积温次之,旬累积日照时数影响弱。高产年气候资源利用率高,低产年气候资源利用率低。更多还原

【Abstract】 The pasture’s productivity simulated by the third-order polynomial growth curve mathematical model in different years in Maqu grassland coincided with the actual value.The simulation results show that the maximum growth rate is 70.2 kg/hm2·d and the minimum is 1.6 kg/hm2·d.The monthly maximum yield is 2 042.5 kg/hm2 and the minimum is 57.6 kg/hm2.From May to September,the 10 days accumulated temperature which is above 0 ℃ increased 1 ℃,the pasture’s dry matter increased 2.54 kg/hm2,and the amount of the precipitation increased every 1 mm in every 10 days,the dry matter increased 7.33 kg/hm2,as well as the sunshine duration increased every one hour in every 10 days,the dry matter increased 3.83 kg/hm2.Considering the difference of the climate tendency for different factors,the ten days precipitation is the main factor which influences the pasture’s yield,and the accumulated temperature in every 10 days plays the second role.The climate resources utilization rate in high production year is higher than that in the low production year.更多还原