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通过将沙棘（HippophaerhamnoidesL．）与3种杨树品种（小黑杨（Populuscv．“Xiaohei”），昭林6号杨（P．cv“Zhaolin06”）和欧美杨64号（P.euramericanecv．“N3016”））的人工林分别按株混和行混两种方式进行混交实验，研究了固氮植物沙棘对亚湿润干旱区的杨树人工林生长和生产力的影响。研究结果表明：无论哪一种杨树品种或混交方式，沙棘与杨树混交后能显著地增加杨树人工林的生长量，林分平均胸径增加6％～38％，林分平均高增加8％～23％。在株混方式中，杨树地上部生物量大于杨树纯林的地上部生物量。但是在行混方式中，呈现相反的规律，这是由于行混方式中单位面积的杨树株数少。无论哪一种杨树品种或混交方式，杨树与沙棘混交林的地上部净生产力大于杨树纯林的地上部生产力。在珠混和行混两种方式中，沙棘占总地上部净生产力的比例分别为20％和41％，但草本植物所占的比重很小。
The effects of Hippophae rhamnoides L. on three poplar species (Populus cv. “Xiaohei”, P. cv “Zhaolin 06”) and P.euramericanecv. “N3016 ”)) Plantation were mixed by mixed lines and mixed two ways to conduct mixed experiments to study the nitrogen-fixing plant seabuckthorn on the subtropical arid poplar plantation growth and productivity. The results showed that the growth of poplar plantations could be obviously increased by the combination of seabuckthorn and poplar, no matter which kind of poplar or mixed, the average DBH increased by 6% -38% and average height increased by 8 % ~ 23%. In the mixed plantation, the aboveground biomass of poplar is larger than the aboveground biomass of poplar pure forest. However, in the row blending mode, the opposite law appears, due to the small number of poplar units per unit area in the row blending mode. Regardless of which poplar species or mixed mode, the above-ground net productivity of poplar and sea buckthorn mixed forest was greater than that of poplar pure forest. Among the two methods, the ratio of seabuckthorn to total net productivity in the upper part is 20% and 41%, respectively, but the proportion of herbaceous plants is very small.