Objective]Natural regeneration of Manchurian ash ( Fraxinus mandshurica ) has been observed in conifer plantations,secondary forests containing Populus davidiana and Betula platyphylla and mixed hardwood secondary forests. However,successful natural regeneration is unlikely in pure secondary forest of F. mandshurica. The objective of this study was to provide some evidences to explain factors that might improve the survival and growth of planted ash seedlings.[Method]One-year-old manchurian ash seedlings were planted under a secondary forest of manchurian ash located at a low-lying site with seasonal water logging. Site preparation was conducted using mounding combined with clearing of ground covers. A randomized blocks experimental design was used and plots with no site disturbance was used as control. Seedlings were either top-pruned to a height of 8 cm right away after planting,or planted without any stem cutting ( average height of control seedlings was 15 . 8 cm ) . The survival and growth of the planted seedlings during the first 3 years after planting and the surface soil moisture and temperature of the planted areas at the third year after planting were investigated and analyzed.[Results]Mounding combined with clearing of ground vegetation cover reduced the moisture of surface soil ant the extent of its variation. Mounding and removal of vegetation cover increased the temperature of surface soil especially during the primary growth season ( May) ,and decreased the extent of temperature reduction in late growth stage ( September) and therefore,homogenized the surface soil temperature. Mounding significantly increased survival and decreased mortality of the non-pruned seedlings,the increases of survival rates in the first,secondary and third year were 7. 17%,13. 37% ,and 15. 56% respectively and the decreasing rates were 100%,64. 73%,and 20. 89% respectively. This treatment significantly enhanced the root-collar diameter and height increment. For non-pruned seedlings,root-collar diameter was increased by 19 . 37%,27 . 13%,35 . 80% and height was increased by 100 . 53%,50 . 00%,64 . 17%respectively in the first,secondary and third year after planting. Mounding also increased the total biomass,total leaf area and number,and also increased the ratio of stem/root biomass. When planted at mounded sites,the top-pruning had no significant effect on survival or growth of seedlings. However,the survival rate and height increment of the top-pruned seedlings was smaller than those of non-pruned seedlings. At non-mounded sites,top-pruning reduced the survival rate. However,there was no significant effect on either height or diameter increment. The top-pruning increased both leaf-area and leaf number, and increased root biomass and leaf biomass. [Conclusion]Poor situation of soil moisture and temperature and the competition with surface vegetation were the two key reasons for the low survival of planted seedlings at non-mounded sites. Improving soil moisture and temperature conditions and reducing the competition from surface vegetation by mounding could promote the survival and growth of the planted seedlings.%【目的】研究高台整地和苗木截干对水曲柳次生林下水曲柳栽植苗成活及生长的影响，以期解释低洼地带水曲柳次生纯林林下水曲柳天然更新不良的原因，为同样立地的水曲柳人工造林提供参考依据。【方法】在水曲柳典型分布区内选择生长在低洼且有季节性积水地段上的水曲柳次生纯林，采用两因素随机区组试验设计，在其林下进行高台整地(配合地被物去除处理，并设置未整地对照)，人工栽植水曲柳1年生苗(栽植后立即截干至8 cm高和未截干保持原15.8 cm平均高2种处理)，对苗木栽植后3个生长季内的成活和成长情况及栽植后第3年的地表水分与温度变化动态进行观察分析。【结果】1)配合死、活地被物去除处理的高台整地可以有效降低表层土壤含水量，且变化幅度明显降低；高台整地可增加生长季初期(5月)地表温度升幅、降低生长季末期(9月)地表温度降幅和生长季地表温度变幅，使地表温度趋于匀质化；2)高台整地可提高栽植苗木的成活率和保存率(未截干情况下，3个生长季分别比未整地高出7.17%，13.37%和15.56%)，降低栽植苗木的生长季死亡率(未截干情况下，3个生长季分别比未整地低100%，64.73%和20.89%)，提高栽植苗木的地径和苗高生长量(未截干情况下，3个生长季内地径和苗高生长量分别比未整地高出19.37%，27.13%和35.80%及100.53%，50.00%和64.17%)，增加苗木生物量和茎根生物量比值，增加苗木叶片的叶面积和数量；3)在高台整地情况下，截干处理对水曲柳苗成活没有显著影响，但截干处理成活率和高生长量小于未截干处理；未整地情况下，截干处理水曲柳苗成活率和保存率显著低于未截干处理，但对苗高生长量和地径生长量无显著影响；截干处理可增加水曲柳苗叶片的面积与数量，提高苗木根和叶生物量积累。【结论】土壤水热状况不良和地被物竞争是中下坡低洼地带水曲柳次生纯林林下水曲柳更新幼苗存活和生长差的重要原因，通过高台整地改善土壤水热状况、削弱地被物竞争，可以促进水曲柳栽植苗的存活和成长。
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