Study On The Heat Balance During The Growing Season Of Quercus Liaotungeusis Koidz Stand In Taiyue Mount Area Shanxi Provice

The forest heat balance is a very important content in forest energy system. The value of heat balance items could be obtained using Bowen-Ratio Energy balance method. The diurnal and seasonal trends of net radiation reflect radiation reflect ratio, sensible heat flux, talent heat flux and soil heat flux could also be obtained with this method. The sap flow flux could be gauged using ICT-2000 auto meteorological station instrument with Thermal Dissipation Method so transpiration flux and transpiration heat flux also could be calculated and then the latent heat flux could be parted into transpiration heat flux and evaporation heat flux. Through gauging the heat balance of Quercus liaotungeusis Koidz deciduous broad-leaved stand under typical weather condition during the whole growing season in Taiyue Mount area Shanxi province, during the whole growing season the monthly average of reflect ratio at canopy height varied from 8% to 12%, the difference of reflect ratio was unconspicuous under different typical weather but was prominent in different months, the reflect ratio at mid-stage of growing season was larger than the ratio at the beginning and the end of season. The seasonal change of the transpiration heat flux and soil heat flux were single-climax curves that the value at mid-stage was larger than that at the beginning and the end of season. During the whole growing season , in radiation balance the total radiation at canopy height of deciduous broad-leaves stand was 2904. 39 MJ ?m2, and the total reflect radiation was 307. 56 MJ ?m2, the reflect ratio average was 10.59%, the total long wave radiation and the total net radiation was 809.24 MJ ?m2 and 1787. 58 MJ ?m2 respective, the ratio to radiation was 27. 86 % and 61.55% respective. The total sensible heat flux, the total transpiration heat flux , the total evaporation heat flux and the total soil heat flux were 640. 00 MJ ?m2, 235. 49 MJ ?m2, 803. 73 MJ ?nf2 and 108. 37 MJ ?m2 respective , and the ratio to net radiation was 35. 80%, 13.17% , 44. 96% and 6. 06% respective.The novelty in this study was the evaportranspiration energy consume could be discriminated into evaporation energy consume and transpiration energy consume, and try the primary explore in parting the evaportranspiration into evaporation and transpiration. It may do well to the explanation of structure and function of forestry ecosystem.