摘要
对H1、H12、J5和J10等4个四川桤木品系的蒸腾特性和水分利用效率进行了研究,结果表明：（1）蒸腾速率日变化呈单峰、双峰曲线2种类型,具有明显的峰值,属轻蒸腾午休型.峰值出现时间因不同曲线类型和不同品系均有差别;蒸腾速率月均值以6月份（H1、H12）、7月份（J5、J10）的最高,分别是2.57、3.65、2.64、3.84 mmol·m^-2s^-1;J10、H12品系的蒸腾速率月均值明显高于J5、H1品系;（2）净光合速率日变化4月呈单峰曲线,6～8月有单峰、双峰2种类型,以6月份最高,H1、H12、J5、J10的净光合速率峰值分别为12.20、18.56、15.64、18.43μmol·m^-2s^-1,8月份最低,分别为6.43、11.73、9.62和10.74μmol·m^-2s^-1;（3）水分利用效率日变化以上午7：00～9：00最高,下午或傍晚较低;4月（H1、J5）、6月（H12和J10）的水分利用效率平均值最大,分别为4.82、5.80、2.98、3.34μmol·mol^-1,且H1和J5分别大于H12、J10.（4）通过多因子回归分析,影响蒸腾速率的关键因子是气孔导度、光照强度与空气温度,H1对光合有效辐射变化不敏感,受CO2浓度影响的品系H12受温度的影响较小,对水分比较敏感.
The transpiration characteristics and water use efficiency of four varieties （H1, H12, J5 and J10i of Alnus cremastogyne were studied in this paper. The results show as following： （1） the diurnal variation of their transpiration rate （Tr） presents a singlepeak curve or double-peak one and possesses an obvious peak value, thus, these varieties belong to poor-transpiration, midday- depression plants; however, the peak value appears in different periods with the difference of curve type and varieties and the monthly average of T, of H1 and H12 shows the maximum in June while J5 and J10 in July, which are 2. 57, 3. 65, 2. 64 and 3. 84μmol·m^-2s^-1, respectively; （2） the diurnal variation of Pn shows a single peak curve in April and reveals a single or double-peak one from June to August ; the maximum peak value of Pn of H1, H12, JS, and J10 are 12.20, 18.56, 15.64 and 18.43 μmol·m^-2s^-1 in June, respectively while their minimum appears in August, which are 6.43, 11.73, 9.62 and 10.74 μmol·m^-2s^-1, respeetively; （3） the diurnal variation of their water use efficiency（WUE） reaches the maximum at 7：00-9：00 but rather lower in the afternoon or evening and the monthly average value of WUE of H1 and J5 reaches the maximum in April, while H12 and J10 in June, which are 4.82, 5.80, 2.98 and 3. 34μmol·mol^-1, respectively; （4） multiple regression analyses show that the major factors affecting transpiration rate are stomatal conductance, light intensity and air temperature; H1 shows a poor sensitivity to the change of photosynthetically active radiation but a good one to CO2 concentration; and H2 is slightly affected by air temperature and sensitive to water.
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2008年第1期1-7,共7页
Journal of Central South University of Forestry & Technology
基金
国家林业局2005长江-2国家“十一五”重点工程科技支撑项目“植被恢复与特色资源高效培育及利用技术试验示范(2006BAD03A16-02)”湖南点研究内容
关键词
植物学
桤木品系
蒸腾特性
水分利用效率
botany
varieties of Alnus cremastogyne
transpiration characteristics
water use efficiency
