海北高寒草甸植被在生长期辐射能量收支探讨

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。

The Study on the Radiant Energy Budget of Alpine Meadow Vegetation in the Sunny Days During the Plant Growing Season

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－1to 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.