摘要
2004年夏在山西方山北京林业大学试验基地，采用LI-1600稳态气孔仪，对不同土壤水分条件下盆栽刺槐的生理指标进行了观测。比较分析了不同水势梯度下、不同时间段刺槐蒸腾耗水速率的变化规律，结果表明：刺槐的蒸腾速率ηt（μg／（s·cm^2））与生理辐射强度Ⅰ（μmol／（s·m^2））成幂函数关系；蒸腾速率ηt（μg／s·cm^2））、气孔阻力Rs／（s·m^2）和土壤体积含水最（W％）之间存在着密切的关系；蒸腾速率一般随光强的增强和土壤水分的提高而增大，刺槐蒸腾速率与土壤水分含量的相关系数平均可达0．8825。通过研究不同土壤水分条件下刺槐蒸腾速率的差异，提出了刺槐水分利用效率的合理供水范围在10％～15％之间，为干旱半干旱地区提高林木的水分利用效率提供了理论依据。
It mainly analyzed the transpiration characteristic of Black locust , major tree for forestation in the Loess Plateau. Physiological indices of Black Locust in different soil water conditions were measured by portable steady porometer （LI- 1600） in the summer of 9.004, in Fangshan, Shanxi Province （Forestry Experimental Station of Beijing Forestry University）. The respohse processes of physiological absorbed radiation （Ⅰ）, stomatal resistance （Rs） , leaf water potential （ψ） and transpiration rate （Tr） to different soil water content were studied. The resuks showed, the relationship between transpiration rate and physiological absorbed radiation of Black Locust in semi-arid regions of Loess Plateau was power function. Meanwhile, the relationship of transpiration rate （ ηt ） and stomatal resistance （ Rs ） with soil water content （ W ） was relatively. Generally, transpiration rate increased with the raising of irradiance and soil water content. The correlation between transpiration rate and soil water content was close. （average logarithmic relations, R^2= 0. 8825）. Furthermore, the transpiration rate could rise greatly with the increase of soil water content. Based on the above analysis of the transpiration rate in different soil water conditions, therefore, to lighten injuring on physiology as transpiration seriously, to increase the rate of survivor and to promote growing, it is necessary to adopt measure as avoiding violent irradiance of the sapling when the soil is short of water. The soil water content as 10%〈SWC〈15 % is beneficial to increase the water use efficiency of plants, which could help plants to enhance water use efficiency in arid and semiarid region.
出处
《水土保持学报》
CSCD
北大核心
2006年第2期122-125,共4页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(3007063)
国家攻关项目(2004BA510B0304)资助
关键词
刺槐
蒸腾
土壤水分
气孔阻力
水分利用效率
Black Locust
transpiration
soil water content
stomatal resistance
water use efficiency
