Studies on the Productivity of Korean White Pine Forest (I) Effects of Temperature, Light and Water Stress on Photosynthesis and Dark Respiration Rates of Leaves

국문 초록 (Abstract)

본 연구(硏究)는 잣나무림(林)의 일차(一次) 생산력(生産力)을 알기위한 것으로, 엽(葉)의 온도(溫度) 광도(光度) 수분결핍(水分缺乏) 등이 광합성속도(光合成速度)및 호흡속도(呼吸速度)에 미치는 영향(影響)을 측정(測定) 보고(報告)한다. 1) 광포화(光飽和)는 40Klwx 전후에서 일어나며 광보상점(光補償点)은 l.0~1.3Klwx 임을 알았다. 2) 당년엽(當年葉)의 광합성(光合成) 속도(速度)가 가장 높고 엽령(葉令)이 증가함에 따라 감소(減少)했다. 3) 온도반응(溫度反應)에 따른 호흡속도(呼吸速度)는 2월엽(月葉)이 8월엽(月葉)보다 2배(倍)정도 높았고, 양자(兩者) 모두 $17^{\circ}C$ 이하에서 심한 감소(減少)를 보였다. 4) 광합성(光合成) 속도(速度)는 약 -10bar에서 감소(減少)가 시작되며 약 -24bar에서 0으로 되었다. 호흡속도(呼吸速度)는 약 -5 bar에서 감소(減少)가 시작 -24bar에서 43% 정도 감소했다. 5) 광합성(光合成)에 관한 최적온도(最適溫度)는 8월 엽(葉)에서 $23{\sim}26^{\circ}C$, 2월엽(月葉)에서 $15{\sim}18^{\circ}C$를 나타냈다.

다국어 초록 (Multilingual Abstract)

This study is to investigate the effects of temperature, light and water deficit on apparent phytosynthesis rate (Pn) and dark respiration rate(Rd) of leaves in the series of studies dealing with primary productivity of korean white pine forest. The results obtained are as follows: 1. The light saturation for Pn occured at about 40 Klux, and light compensation at 1.0 to 1.3 Klux. 2. The Pn of current leaves was highest, and Pn was decreased with increasing leaf age. 3. The Rd on the response of temperature in February was about two times value in all of the temperature ranges as compared with the ones in August. 4. The incipient water stress, above which Pn and Rd declined from 100%, was different for Pn(-10bar). The high water stress required to reduce Pn to nearly 0%, at -24 bar, but Rd was only 43% at -24 bar. 5. The optimum temperature range for Pn showed about 15 to $18^{\circ}C$ in February and 23 to $26^{\circ}C$ in August.