以2003年种植的小叶锦鸡儿（Caragana microphylla Lam.）为研究材料，于2018年秋季进行平茬处理（留茬高度分别为5、10、15、20和25 cm），对次年生长季（5月至9月）不同留茬高度处理小叶锦鸡儿叶片部分光合指标和土壤含水量进行比较和分析。结果表明：5个平茬处理中，留茬高度15 cm处理小叶锦鸡儿的株高在6月至9月均最高。7月，不同处理小叶锦鸡儿的净光合速率（Pn）日变化存在明显的“午休”现象；9月，Pn值无“午休”现象且达到最高。5月至9月，平茬处理小叶锦鸡儿的Pn值显著高于未平茬处理。留茬高度5、10、20和25 cm处理的Pn日均值呈逐渐升高的趋势，留茬高度15 cm处理的Pn日均值呈“升高—降低—升高”的趋势。不同处理小叶锦鸡儿的蒸腾速率（Tr）日均值呈“升高—降低—升高—降低”的趋势；而水分利用效率（WUE）日均值基本呈“降低—升高—降低”的趋势。留茬高度15 cm处理小叶锦鸡儿叶片Pn 5月至9月均值最高，分别较未平茬处理以及留茬高度5、10、20和25 cm处理增加了1.46、0.48、0.25、0.20和0.49倍；留茬高度20 cm处理的Tr 5月至9月均值最高，留茬高度15 cm处理的Tr 5月至9月均值次之；留茬高度15 cm处理的WUE 5月至9月均值也最高，分别较未平茬处理以及留茬高度5、10、20和25 cm处理增加了0.66、0.15、0.25、0.45和0.56倍。留茬高度15 cm处理0~100 cm土层土壤水分消耗较大，60~100 cm土层土壤水分消耗尤为突出，这与其具有较高的水分利用效率相吻合。总体上看，留茬高度15 cm处理的小叶锦鸡儿次年具有较强的光合能力，快速再生能力较强，建议小叶锦鸡儿的留茬高度为15 cm。

 Taking Caragana microphylla Lam. planted in 2003 as research materials， stumping treatment was taken in autumn of 2018， with stubble height of 5， 10， 15， 20， and 25 cm respectively. In the next growing season （from May to Sept.）， some photosynthetic indexes of leaves and soil water content of C. microphylla in different stubble height treatments were compared and analyzed. The results show that plant height of C. microphylla in treatment with stubble height of 15 cm is the highest from Jun. to Sept. among the 5 stumping treatments. In Jul., the diurnal variation of net photosynthetic rate （Pn） of C. microphylla in different treatments has a “lunch break” phenomenon. In Sept.， Pn value reaches the highest without the “lunch break” phenomenon. From May to Sept.， Pn values of C. microphylla treated with stumping treatments are significantly higher than that of no stumping treatment. The daily averages of Pn value of treatments with stubble height of 5， 10， 20， and 25 cm show gradually increasing trends， and that of treatment with stubble height of 15 cm shows an “increasing-decreasing-increasing” trend. The daily average of transpiration rate （Tr） of C. microphylla in different treatments shows an “increasing-decreasing-increasing-decreasing” trend， while the daily average of water use efficiency （WUE） basically shows a “decreasing-increasing-decreasing” trend. Compared with no stumping treatment and treatments with stubble height of 5， 10， 20， and 25 cm， the  monthly average from May to Sept. of Pn value of treatment with stubble height of 15 cm is the highest， which increases by 1.46， 0.48， 0.25， 0.20， and 0.49 times respectively. The monthly average from May to Sept. of Tr value of treatment with stubble height of 20 cm is the highest， followed by treatment with stubble height of 15 cm. Compared with no stumping treatment and treatments with stubble height of 5， 10， 20， and 25 cm， the  monthly average from May to Sept. of WUE value of treatment with stubble height of 15 cm is also the highest， which increases by 0.66， 0.15， 0.25， 0.45， and 0.56 times respectively. The water consumption of 0-100 cm soil layer of treatment with stubble height of 15 cm is large， especially in 60-100 cm soil layer， which is consistent with its high water use efficiency. In general， C. microphylla in treatment with stubble height of 15 cm has relatively strong photosynthetic capacity and rapid regeneration capacity in the next year， therefore， 15 cm stubble height is recommended for C. microphylla.