Abstract: These studies were carried out at the Institute of Silviculture University of Freiburg，the Federal Republic of Germany from 1983- 1984．In a 19 years-old Picea abies stand，four trees chosen at random for the test．The tes t shoots were obtained from the 2nd，4th, fith and 7th crown layers of these four test trees．Under the constant conditions，the needle gas exchange was measured in annual shoots(1983)and two years—old shoots(1982)．Here are the main results． The foilowing data is drRWll from the shoots of the 2nd and 7th crowll layer．The 2nd crowll layer indicate the upper part of the crown，while the 7th indieaters the lower part of the crown．The needle photosynthetic capacity decreased as the crown increased．There Wa Sadecrea．Se of 20．4—27.8，in the annual shoots and of 40.5—47.9％in the two years—old shoots．However，the ratio of needle water loss in—creased as the CROWR layers increased．IN the annual shoot，it increased by 4．8—23．7％，38．8—61．5％respectively．The intensity of needle dark respiration also increased as the crown layers increased．It increased by 5．8—10．9％in the annual shoots and by 3.5一l7.3％in the two years-old shoots．The photosynthetic economic coefficient changed in the same way aS the needle photosynthetic capacity did．It dereased by 10——26％in the annual shoots and by 44——了1％in the two years—old shoots