It is studied that

among the climatic element at Huoditang forest farm in Qinling moun-tain range

increase of direct solar radiation

gross solar radiation

net radiation and wind speed areaccompanied by the progressive going up of elevation

and direct solar radiation and gross radiatlonincrease with elevation by the law of exponential function。 However

scattered radiation

ground ef-fective radiation

temperature

moisture pressure precipitation and evaporation capacity are goingdown with the increase of altitude。Scattered radiation and moisture Pressure decrease exponentiallywith the elevation going up

while ground effective radiation and precipilaion vary parabolically withthe elevation

which means when elevatton goes up both elements increase at the begining

but turnto decrease in a certain elevation later.The elevation is 2500 m when the maxium effective radiationappears

2 000 m when the maxium precipitation emerges.