The leaf nutrient, biomass and carbon reserve of 9-year-old Populus×euramericana cv. ‘74/76’ stump grafting stand with 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’as rootstock, 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and 9-year-old P.×euramericana cv. ‘74/76’ planting stands were compared. The result showed that the average increment and the annual average increment of stump grafting stand were greater than the two planting stands. The total nitrogen content in leaves of stump grafting stand was the highest, and it was 1.26 times and 1.05 times as much as that of the planting stands of Populus×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and P.×euramericana cv. ‘74/76’ separately. The total phosphorus content of stump grafting stand was 1.3 times as much as that of planting stand of 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’, but there was little difference between stump graftin stand and planting stand of 9-year-old P.×euramericana cv. ‘74/76’. The total potassium of stump grafting stand was 46.6% and 95.8% lesser than that of the planting stands of P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and P.×euramericana cv. ‘74/76’. The biomass of aerial parts and the biomasses of trunk, branches and leaves of stump grafting stand were 1.84, 1.80, 1.76, and 3.00 times as much as that of planting stand of P.×euramericana cv. ‘74/76’ separately. The total root biomass of the stump grafting stand was 1.42 times and 7.68 times as much as that of planting stands of 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and 9-year-old P.×euramericana cv. ‘74/76’. There was an obvious advantage in carbon reserve from all the parts of the stump grafting stand and the carbon sequestration capacity was the highest, which was 2.66 times and 1.62 times as much as that of planting stands of 26-year-old P.×xiaozhuanica W.Y.Hsu et Liang cv.‘Popularis’ and 9-year-old P.×euramericana cv. ‘74/76’. These showed that the stump grafting stand had more advantages than planting stands.

在晋西黄土区，研究了荒草地、锦鸡儿灌木林地和刺槐乔木林地3种典型植被不同土层的土壤密度、含水量、贮水能力和入渗性能的差异及其相关性，结果显示：3种植被类型都能有效减小表层（0~20 cm）土壤密度； 3种植被类型表层（0~20 cm）的土壤滞留贮水量较大，锦鸡儿林地（198.80 t·m-3）>刺槐林地（166.10 t·m-3）>荒草地（87.37 t·m-3），20~40 cm土层的土壤滞留贮水量也是锦鸡儿林地（127.30 t·m-3）>刺槐林地（55.60 t·m-3）>荒草地（47.30 t·m-3），表明在3种植被类型中，锦鸡儿林地对晋西黄土丘陵区土壤水分的涵养作用最强；锦鸡儿林地的土壤稳渗速率最大，为1.80 mm·min-1，刺槐林地次之，为1.46 mm·min-1，荒草地依然最小，且锦鸡儿林地土壤的均渗速率最大，为4.81 mm·min-1，其次是刺槐林地，为4.51 mm·min-1，荒草地最小。土壤密度与滞留贮水量呈极显著负相关关系，与土壤初渗速率和均渗速率呈极显著负相关关系，与稳渗速率呈显著负相关关系，非毛管孔隙度与稳渗速率和均渗速率存在极显著相关关系。 Kostiakov模型和Horton模型对晋西黄土区3种植被类型土壤入渗过程模拟的拟合系数高达0.97和0.95，明显优于Philip模型（0.43）。

In order to compare the differences in eco-physiological characteristics between male and female plants and to further understand the ecological adaptability of Rhus typhina Linn., the diurnal variations of photosynthetic parameters and the fluorescence characteristics of male and female plants were determined respectively with photosynthesis system (CIRAS-2) and portable chlorophyll fluorometer (PAM-2100). The relative chlorophyll content was determined with relative chlorophyll content determination (SPAD-502). The length and width of leaf were measured with ruler. The results showed that the SPAD of male was greater than that of the female by 9.6%. The diurnal variation of net photosynthetic rate of male and female plants showed obvious midday depression. The daily mean of net photosynthetic rate of male plant was greater than that of the female by 22.7%, and there was significant difference between them. The daily means of transpiration rate was greater than that of the female by 18.5%. The water use efficiency of male plant was 2.3 μmol·mmol-1, which was greater than that of the female by 21.7%, and there was significant differences between them. The diurnal variations of light use efficiency of male and female plants were similar but the light use efficiency of male was higher. The Fv/Fm of male plant was higher than 0.76 and was higher than that of the female during the measurement period. The female reduced to the lowest which was 0.69 at 13:00 p.m. Both the leaf length and width of female were smaller, but the ratio of length and width was greater compared with the male, and there was significant difference between them. The net photosynthetic rate, water use efficiency and light use efficiency of male were higher than that of female, and it had stronger adaptability to environment.