【Objective】This study aimed to explain the formation mechanism of Picea balfouriana tree line in terms of nutrient elements.Effects of different soil temperature and moisture on the growth and physiology,and nutrient concentration (unit mass content) and content in responses to low soil-temperature and water stress(drought and saturated water stress) were studied by simulating changes of soil temperature and moisture.【Method】In this study,5-year-old P.fouriana seedlings were taken as experimental material.The experiment was conducted in a walk-inartificial climate chamber with a nested design.Five soil temperature regimes (2,7,12,17,22 ℃) and three soil moisture treatments(drought treatment,normal moisture treatment and saturated moisture treatment) were set up.A total of 135 seedlings were used in the experiment,and 9 seedlings were randomly selected in each treatment.After 4 months treatments,phenotypic traits,dry mass,total nitrogen and total phosphorus of seedlings were measured and analyzed.At the same time,soil samples were collected to measure total nitrogen and total phosphorus.【Result】Soil temperature treatments had no significant effects on basal diameter and height increment,while soil moisture treatments had significant effects on height increment.Drought treatment significantly reduced height increment at 2 ℃ and 7 ℃,however the effect was no longer significant with soil temperature increasing.Soil temperature treatments had no significant influences on nitrogen(N) and phosphorus (P) concentration in soil,while drought stress significantly increased N and P concentration in soil.The N and P concentration in different organs,and N content in annual needles of spruce seedlings were significantly decreased with soil temperature decreasing.Drought and saturated water stress significantly reduced N concentration in annual needles and annual branches.Saturated water stress significantly reduced P concentration in annual needle,and drought stress significantly reduced P concentration in annual branch,stem and root.Drought and saturated water stress significantly decreased N and P content in annual needle and root,and the higher the temperature the effect was more significant.【Conclusion】In the short term,low soil temperature and water stress had no significant limitations on phenotypic traits,while the stress had significant effects on N,P concentration and content,especially in annual needle and root.The deficiency of N and P content in organs of the seedlings caused by extreme climate changes,such as low temperature stress and water stress,is likely to limit the vertical distribution of P.balfouriana in the western of Sichuan province,in China.In addition,there was a significant interaction between soil temperature and moisture treatment,The effects of water stress on nutrient in various organs of the seedlings was significantly reduced with soil temperature decreasing.It was suggested that low soil temperature became the leading factor for the deficiency of nutrient elements in various organs of P.balfouriana seedlings with the increase of altitude.