温度对高山植物紫花针茅种子萌发特性的影响

温度是影响种子萌发的重要因子，在气候变暖和草地退化的背景下，认识温度变化对紫花针茅（Stipa purpurea） 种子萌发的影响有重要意义。作者系统研究了6个恒温条件（5、10、15、20、25、30℃）和3个变温条件（5/15、10/20、15/25℃）对不同居群紫花针茅种子萌发特性的影响。结果表明，紫花针茅种子适宜的萌发温度范围为15~25℃，低于10℃或高于30℃的温度都会抑制种子的萌发；与对应的恒温条件相比，变温条件不能起到促进紫花针茅种子萌发的作用；不同居群紫花针茅种子萌发对温度的响应既有相同点，也有不同点；海拔高度与种子萌发率存在极显著负相关关系，种子萌发季土壤温度与种子萌发存在显著负相关关系。本研究将为合理的保护和恢复紫花针茅草地提供一定科学依据。

Effects of Temperatures on Seed Germination Characteristics of Alpine Plant Stipa purpurea (Poaceae)*

Temperature is an important factor to impact seed germination. Under the background of climate warming and grassland degradation, it includes great value to understand temperature change on seed germination of Stipa purpurea. In the present study, six constant temperature conditions (5, 10, 15, 20, 25, and 30℃) and three variable temperature conditions (5/15, 10/20, and 15/25℃) were set to systematically detect the effects of temperatures on seed germination characteristics of Stipa purpurea from three different populations. The results showed that the more suitable seed germination temperature of Spurpurea ranged from 15 to 25℃, and temperatures lower than 10℃ or higher than 30℃ would not be conducive to seed germination. Compared to the corresponding constant temperatures, variable temperature conditions had no effects on promoting seed germination of Spurpurea. Seed germination characteristics of Spurpurea from different populations responded to temperature change with both same and different points. Correlation analysis revealed that altitude showed highly significant negative correlation with the germination rate, whereas soil temperature of seed germination seasons in the field had significant negative correlation with seed germination delay. This study will provide a scientific basis for reasonable protection and restoration of Spurpurea meadow.