水分条件对梭梭气体交换特性的影响  

Effects of Moisture Conditions on the Gas Exchange of Haloxylon ammodendron

作　　者：吴琦[1] 张希明[1] 

机构地区：[1]中国科学院新疆生态与地理研究所,乌鲁木齐830011

出　　处：《干旱区研究》2005年第1期79-84,共6页Arid Zone Research

基　　金：973项目专题 (G19990 43 5 0 5 0 4);中国科学院新疆生态与地理研究所创新领域前沿项目 (KZCX -XJ0 1-0 5 )

摘　　要：对梭梭 (Haloxylonammodendron) 在不同沙地水分条件下的净光合速率 (An)、蒸腾速率 (E)、气孔导度(gs)、水分利用效率 (WUE)和光响应曲线进行了测定和分析。结果表明 ,梭梭的净光合速率、蒸腾速率、气孔导度均随土壤含水率的增加而升高 ,光补偿点 (LCP)随含水率的增加呈下降趋势 ,表观量子效率 (Φ) 随含水率的增加而增大。在沙地含水率为 2 .2 5 %和 2 .6 3%时 ,梭梭的水分利用效率较高 ;含水率为 4 .2 9% ,6 .2 7% ,9.97%时 ,水分利用效率次之 ,且三者差异不大 ;当含水率为 1.6 5 %时 ,水分利用效率最低。Haloxylon ammodendron is the main community composition species temperate deserts and grows extensively in Central Asia. The area of Haloxylon ammodendron in China is 6.53×106 hm2, and it in Xinjiang occupies 56% of the total area in China. Haloxylon ammodendron has an extremely strong adaptability to arid desert environment and is a good species in psammophytes for sand-fixing. In this paper, the photosynthetic rate, transpiration rate, stomatal conductance, moisture use efficiency and sunshine response curve of Haloxylon ammodendron under the different moisture conditions in sandlands are measured and analyzed. The results show that the net photosynthetic rate, transpiration rate and stomatal conductance of Haloxylon ammodendron increase with the increase of soil moisture content, but the sunshine compensation point decreases with the increase of soil moisture content. The apparent quantum efficiency increases with the increase of soil moisture content. The moisture use efficiency of Haloxylon ammodendron is high when soil moisture contents are 2.25% and 2.63% respectively; the moisture use efficiency is low when soil moisture contents are 4.29%, 6.27% and 9.97% respectively, and the difference of moisture use efficiency under such soil moisture contents is not so big; the moisture use efficiency of Haloxylon ammodendron is the lowest when soil moisture content is 1.65%.

关 键 词：水分利用效率 水分条件 梭梭 蒸腾速率 净光合速率 沙地 气孔导度 气体交换 表观量子效率 光响应 

分 类 号：Q948[生物学—植物学]