With the decreasing of soil water level, the efficiency of water use efficiency and stomatal limitation value kept stable, but the root and the rhizome grew more than the aboveground part.

• 研究表明，甘草的光合特性与生物量分配格局对于干旱环境具有很强的适应能力，引起甘草叶片光合速率下降的主要原因是非气孔因素。