A primary study on turbulent fluxes over surface layer in the region of cropland to grassland conversion in southern Ningxia

Abstract

Abstract: Based on the data of microclimatic observation during 2002 to 2003,and using Bowen ratio energy balance method,the characteristics of net radiation flux,sensible heat flux,latent heat flux and heat flux in soil over surface in the region of cropland to grassland conversion in southern Ningxia were analyzed respectively.The results showed that the fluxes changed regularly during day time.Sensible heat flux was up to 50% of net radiation and generally reached 80%～100%.The latent fluxes were positive in all day in summer and daytime in autumn,and those in the morning of spring and evening of autumn were negative.The budget of heat fluxes in soil in spring and winter were greater than that in summer and autumn.

Key words: Fate of apex buds, Box-counting dimension, Branching type, Branching pattern

CLC Number:

ZHANG Xiaoyu, WANG Lianxi, YUAN Haiyan. A primary study on turbulent fluxes over surface layer in the region of cropland to grassland conversion in southern Ningxia[J]. cje, 2004, (6): 171-173.

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