Abstract: There area obvious daily variation patterns of the radiant budget items of Haibei alpine meadow vegetation in the sunny days.The radiant values reach the maximum during 13;00—14;00.The daily net radiant flux of soil surface is varied from 158W·m^-2 ·min^-1 to 499W·m^-2 ·min^-1 .The soil surface is under the condition of absorbing heat from 8;00 or 9;00 to 18;00,whereas the heat is out from soil surface from 18;00 to 8;00 of the next morning.Higher in the morning or the evening,the albedo is the lowest at 13;00 more or less during the whole day,however.The September;They are from 0.197 to 0.215 at noon;and from 0.239 to 0.485 in the morning or the evening;and 0.251 during 3 days in different season and 0.214 from 11;00 to 15;00.

Key words: Alpine meadow vegetation, Plant growing season, Radiant energy budget

摘要： 在晴天,海北高寒草甸植被辐射的各收支项均有明显的日变化规律,在中午13～14h最大。地表净辐射通量日变化在-158～499W·m^-2,8～9h到18h地表面净得到热量,地表处于吸热阶段,18h～翌晨8h区域净损失热量。反射率在早晨与傍晚最高,13h左右最低。植物生长季的4～9月,中午反射率约在0.20～0.22,早晨与傍晚在0.24～0.49,不同季节的3d日平均反射率为0.25,11h～15h平均为0.21。

关键词: 高寒草甸植被, 植物生长期, 辐射能量收支