中文摘要：

2003年6月-2004年10月植物生长季．利用表面覆盖油毡的非称重式蒸渗池测定了油蒿和柠条的蒸腾量．观测了土壤水分平衡场的蒸散量及植物地上部分生长情况。结果表明。蒸渗池测定结果通过单位换算统一和尺度转换，同LI-1600气孔计测定结果进行方差分析表明物种间（油蒿和柠条）差异达显著水平（P〈0．05）．测定方法间（蒸渗池和LI-1600气孔计）差异不显著。从而说明．在干旱沙漠区利用蒸渗池表面覆盖油毡测定植物蒸腾是可行的，以叶面积指数和有效盖度为基础进行叶片水平与种群水平间的尺度转换是成功的；同时，基于蒸渗池测定结果推算出了土壤水分平衡场4个样地的蒸腾总量。2003年的降水量约是2004年降水量110．9mm的2倍多；受此影响，2003年的植物地上部分生长情况好于2004年；同时．干旱不仅降低了样地内植物的蒸腾量和蒸散量，而且增加了降水的蒸发损失。

英文摘要：

In the plant growth season June 2003 to October 2004, the transpiration of Arternisia ordosica and Caragana korshinskii were determined by non-weighing lysimeter cornered with bitumen felt, and by evapotranspiration from the plant＇s above-ground parts in four quadrats of a Soil Water Balance Experimental Plot at the Shapotou Desert Research and Experiment station. The transpirations were determined by lysimeters through unit integration and scale convertion before comparison and analyzis by ANOVA. The results from a LI-1600 stoma meter showed that the difference between species was significant （P〈0.05）, but the difference between methods was not. Thus it is feasible to determine plant transpiration by non weighing lysimeter covered with bitumen felt in arid desert areas, and is successful from a leaf level scale to a plant population level based on effective canopy and leaf area index. The gross transpirations of plants in four quadrats were calculated from the results of non weighing lysimeter. The precipitation in 2003 was about twice （110.9 mm） of that in 2004, with the result that the growth of above-ground plant parts in 2003 was better than that in 2004 over the same time period. Drought not only decreases the amount of transpiration and evapo-transpiration, but increases precipitation loss by evaporation.