【摘要】 利用便携式光合作用测定系统测定了陕北吴旗县沙棘年生长季内叶片净光合速率随光照强度和CO2浓度的变化规律,并测定了沙棘叶片的蒸腾速率(Tr)和水分利用率(WUE)。结果表明:沙棘叶片光补偿点(LCP)在年生长季内的变化范围为15.66~112.31μmol/(m2.s),光饱和点(LSP)变化范围为1 327.39~1 638.89μmol/(m2.s),表观光量子效率(Φ)的变化范围为0.0052~0.0122μmol/mol;沙棘叶片的CO2补偿点(CCP)在年生长季内的变化范围为120.83~278.29μmol/mol,CO2饱和点(CSP)的变化范围为192.24~775.59μmol/mol。表明沙棘为C3植物,不耐荫,宜栽植在阳光充足的地方。沙棘在年生长季内Tr的变化为:8月、9月高于6月、7月、5月;8月份的蒸腾速率最高,5月份的蒸腾速率最低;WUE高低排序为:9月>5月>8月>7月>6月。更多还原

【Abstract】 With the Li-6400 portable photosynthesis system the photosynthetic characteristics in leaves of Hippophae rhamnoides L.during different period was determined.The main results were as follows: the light compensation points（LCP） in leaves of Hippophae rhamnoides L.changed from 15.66 to 112.31（μmol/（m²·s）） in different period,the light saturation points（LSP） varied from 1 327.39 to 1 638.89（μmol/（m²·s）） and the apparent photon utilization efficiency varied from 0.0052 to 0.0122 μmol/mol;the CO₂ compensation point（CCP） of photosynthesis varied from 120.83 to 278.29 μmol/mol;the CO₂ saturation points（CSP） varied from 192.24 to 775.59 μmol/mol.The Tr of Hippophae rhamnoides L.is in Sept.and Aug.higher than in Jun.,Jul.and May,and is at the highest in Aug.,at the lowest in May;the WUE shows Sept.>May.>Aug.>Jun.>Jul..更多还原