Effects of Artificial Water Treatment on Chlorophyll Contents and Photosynthetic Characteristics in Fraxinus rhynchophylla and Fraxinus mandshurica Seedlings
인위적인 토양내 수분처리 결과 물푸레나무와 들메나무 모두 6월〈8월〈9월로 갈수록 엽록소 함량이 증가하였다. 생육기간이 지나는 동안 엽록소 a는 0.89mg/g에서 1.67mg/g로, 엽록소 b는 0.18mg/g에서 0.44mg/g을 나타냈으며, 두 수종 모두 6월보다 8월과 9월에 높은 함량 증가를 보였다. 두 수종의 광합성율을 보면, 물푸레나무는 각 토양수분 처리구마다 광합성율의 차이를 보였으며, 충분한 토양수분처리구(90~78%)의 묘목이 상대적으로 낮은 토양수분조건에서 자란 묘목보다 높은 경향을 나타냈다. 들메나무 역시 물푸레나무와 비슷한 경향을 보였으며, 토양수분이 높을수록 광합성률이 높게 나타났고, 감소할수록 광합성률이 감소하였다. 광합성율의 생육시기별 변화는 두 수종 모두 9월〉8월〉6월 순으로. 9월에 상대적으로 높은 광합성률을 나타냈다. 이로 미루어보면 두 수종은 생장시기에 상관없이 수분함량이 높은 처리구에서 광합성이 활발히 이루어지는 것으로 생각된다.
The content of chlorophyll a, b have generally increased for Fraxinus rhynchophylla and Fraxinus mandshuricain the order of month of June 〈August and 〈September according to artificial water treatment. As similar tendency to F. rhynchophylla, the chlorophyll a content of F. mandshurica grown from different treatments of A, B, C and D also demonstrated increment from 0.89 to 1.67 mg/g and the chlorophyll b showed increment from 0.18 to 0.44 mg/g in the order of June 〈August 〈September period. Both F. rhynchophylla and F. mandshurica showed increment in amount of chlorophyll a and b with the lapse of growing period and the increment amount was higher between August and September than that of between June and August. The photosynthetic characteristics that respond to moisture process demonstrated decrease tendency as the moisture condition of the soil is low and as the stress lasted longer. The results showed even more irregular patterns in September. F. rhynchophylla that showed higher photosynthetic rate even in September that has past growth time due to the A treatment which has relatively fair soil moisture condition, the B, C and D treatments distracted by stress due to insufficient moisture in the soil are showing relatively lower photosynthetic rate during a comparison of photosynthetic rate by growth stage. As similar tendency to F. rhynchophylla, F. mandshurica also demonstrated higher photosynthetic rate according to the treatments in the order of A〉B〉C and 〉D. Therefore we suppose the photosynthesis rate will increase if the moisture level is high and in regardless of the growth stage.