地理学报 ›› 1978, Vol. 33 ›› Issue (2): 156-162.doi: 10.11821/xb197802006

• 论文 • 上一篇    

海拉尔东部开垦地与草场地表热量平衡及其对尘埃输送的影响

谢贤群, 鲍士柱   

  1. 中国科学院地理研究所
  • 出版日期:1978-07-15 发布日期:1978-07-15

THE HEAT BALANCE OF THE CULTIVATED AREA AND THE GRASSLAND IN THE HAI-LAERH REGION AND ITS EFFECT ON DUST TRANSPORT

Shieh Shiarn-chyurn, Pao Shin-chu   

  1. Institute of Geography Academia Sinica
  • Online:1978-07-15 Published:1978-07-15

摘要: 本文对呼伦贝尔草原海拉尔东部开垦地与草场春夏之交地表面热量平衡特征进行了分析,并讨论了草原开垦后,因下垫面热力特征的变化,而导致草原上空大气含尘量增加的原因。

关键词: 开垦地, 地表热量平衡, 蒸发耗热量, 海拉尔, 下垫面, 辐射平衡, 日变化, 含尘量, 交换通量, 湍流热通量

Abstract: This paper analyses the thermal regime of the underlying surface in the cul-tivated area of Hulun-Bir steppe and discusses the increase of atmospheric dust content over the area caused by the variation of the thermal condition of underlying surface after cultivating.The result of observation shows that after cultivating the albedo of the cultivated land is about 0.13 to 0.18, with a mean value of 0.16. The albedo for grassland is about 0.16-0.21, with a mean value of 0.19. The surface temperature of cultivated land is about 3-4℃ higher tham that of grassland during daytime, so that the effec-tive radiation of cultivated land is larger than that of grassland. The heat balance for cultivated land is quite different from that of the grassland. The net radiation on the grassland is mainly used for the evaporation, which constitutes about 60% to 70% of radiation balance, and is larger than that of the cultivated lanid. But the turbulent heat flux on cultivated land is larger than that on grassland, about 4 times larger at noon, sometimes even 10 times larger. The turbulent) heat flux on cultivated land constitutes about 60% of radiation balance so that the net radiation of cultivated land is mainly used for the turbulent transport of heat into the air.The relationship between the diurnal variation of the turbidity of atmosphere and the turbulent heat flux in spring over Pa-Kshi Farm shows that the turbulent heat flux increase rapidly following the development of turbulent thermal instability. In the meantime, the increasing turbidity of atmosphere over cultivated area is due to the increasing transport of dust particle from the surface of the earth to the air. This is the cause why there occurs frequently the dust bowls on the cultivated land of Hulun-Bir steppe during April and May.