The influences of climate factors caused by changing vegetation with development

研究了植被变化对气温、净辐射、蒸散量和太阳辐射等气候因子的影响。当植被密度稀薄时，水稻和草地上的冠层温度高于森林。但随着林冠的生长和植被密度的增加，林木的冠层温度逐渐变得与水稻和草地相当。60%以上的绿地面积，有效辐射占净辐射的比例随着绿地面积的增加而增加，绿地面积受反照率的影响可用公式表示：0.121 G+10.321 C+0.835 S+3.406(G：绿地面积，C：连续降雨日数，S：大气太阳辐射)。并利用不同的冠层模型观测了不同植被类型的净辐射变化和夜间降温效果。不同冠层模式的冠层长波辐射不同，导致地表温度和气温发生变化，冠层下热量收支受植被厚度的影响，进入土壤的热量随植被厚度的增加而减小，而感热和潜热则随植被厚度的增加而增大。

The influences of the climate factors, i. e. air temperature, net radiation, evapotranspiratio and solar radiation, caused by changing vegetation were studied.The canopy temperature above paddy rice and grass higher than that of the forest, when the density of vegetations was thin. Howver, the canopy temperature of forest became equal to that of paddy rice and grass, when the canopys were grown up and the density of vegetations became thick. In conclusion, air temperature will be variable and will raise up, when the forest was changed to the paddy field and the grass land.The ratio of effective radiation to net radiation increased with increasing green covered area for above 60 % of greencovered area, and greencovered area was affected by the albedo that was expressed a equation;0.121 G + 10.321 C + 0.835 S + 3.406 ( G:greencovered area, C: continuous rain fall days, S: solar radiation over atmosphere ). Also the changing of the net radiation and the effect of night cooling by difference of vegetation were obsereved by using various canopy models. The longwave radiations from canopies are different for each canopy model, and consequently their surface temperatures and air temperatures changed.The heat budget under canopy is affected by thickness of vegetation and the heat transfer into soil became small with its thickness, otherhand, sensible heat and latent heat became large with it.