Evaporation of snow intercepted by forest canopies
1993
Nakai, Y. (Forestry and Forest Products Research Inst., Sapporo (Japan). Hokkaido Branch) | Kitahara, H. | Sakamoto, T. | Saito, T. | Terajima, T.
Field investigations of maximum snow-water-equivalents both in and out of various forests and net snowfalls of a todomatsu (Abies sachalinensis Masters) forest, and measurements of snow weights on coniferous branches, were conducted to estimate snow interceptions by forests. The following findings were obtained: 1) the maximum snow-water-equivalent in ever-green coniferous forests was 30 to 50% smaller than that in clear cut areas. 2) The interception rate of todomatsu forest was 50% of the 58mm-precipitation during 19 days. 3) The evaporation from snow per unit area of coniferous branches was approximately equal to the evaporation from snow on flat boards but a little larger within a day after a snowfall. 4) Evaporation from snow on canopies of coniferous forests was estimated to be as large as the multiplication of evaporation form snow on flat boards by the average number of branch layers per unit of ground area. 5) Evaporation from snow on coniferous branches had its maximum rates with snow amounts approximately on coniferous branches had its maximum rates with snow amounts approximately between 1.5 and 3 mm per unit of branch area, when air temperature was below 0 degrees C and wind velocity was below 0.9 m/sec. 6) The maximum snow amount on todomatsu branches was about 4 mm per unit branch area when the average air temperature was below -3 degrees C
显示更多 [+] 显示较少 [-]