The Accumulation And Distribution Of Photosynthesis Product In Elevated Carbon Dioxide

The main tree species of northeast area(Pinus koraiensis, Fraxinas mandshurica, Betula platyphylla, Quercus mongolica are taken some measurement of photosynthesis and other physiological parameter in ambient and elevated carbon dioxide with Li-6400 system. With the measurement of height, biomass, leaf area, diameter, the root shoot ratio, the percent of different organs are calculated. Utilizing the mean net photosynthesis rate of different stage and weather type, we can get the net accumulation of whole growing season. With the analysis, there are some conclusions as follows:Elevated carbon dioxide increased leaf are, especially in the primary period, the amount according to the tree species: Betula platyphylla increased 122.62%, Fraxinas mandshurica is I 3.27%;the height of Fraxinas mandshurica increased 120.8%,decreased the diameter of Betula platyphylla 40.9%.In ambient conditions, the distribution type of Fraxinas mandshurica is mainly distributed to root and the value is 57.79) Betula pla!yphylla is mainly distributed to root and the value is 41.77%, Pinus koraiensis is mainly distributed to leaf and the value is63 .10%; while in elevated carbon dioxide Fraxinas mandshurica is mainly distributed to root and the value is 47.45%, Betula platyphylla is mainly distributed to shoot and the value is45.33%, Pinus koraiensis is mainly distributed to leaf and the value is 67.41% , Quercus mongolica is mainly distributed to leaf and the value is 56.27%.The root shoot ratio is decreased in elevated carbon dioxide and most photosynthesis products are used to increase above-ground growth, the distribution type is similar to that of ambient and the exact type and is different from tree species.