Dissertation Research: Snow-melt Gradients and the Distribution of Potentilla Species

9520859 Stratton我们正在研究委陵菜的生长和繁殖时机的变化，以应对高山环境中积雪融化的时间梯度。我们问，观察到的变异是由表型可塑性还是遗传分化造成的。实验将操纵积雪融化的时间，这决定了生长季的长度。相互移栽实验和植物密度控制将决定适应一种融雪制度的地点是否在其他类型的制度下无效。将比较广域物种和受限物种的反应，以确定生长和繁殖方面的差异如何限制物种边界。我们的结果将增加我们对物种水平变异在应对环境变化中的重要性的理解。更具体地说，我们将确定气候变化导致的融雪制度的改变如何导致高山植物的持续表型反应、分布限制的变化或局部灭绝。

9520859 STRATTON We are studying the variation in growth and the timing of reproduction in species of Potentilla in response to a gradient in the timing of snow melt in alpine environments. We ask whether the observed variation results from phenotypic plasticity or genetic differentiation. Experiments will manipulate the timing of snow melt which determines length of the growing season. Reciprocal transplant experiments and plant density manipulations will determine whether adaptation to sites of one snow melting regime are ineffective in other types of regimes. The responses of broad-ranging versus more restricted species will be compared to determine how variation in growth and reproduction restricts species boundaries. Our results will increase our understanding of the importance of species-level variability in responding to environmental change. More specifically we will determine how alteration of snow-melt regimes due to climate change could lead to sustained phenotypic responses, shifts in distribution limits, or local extinctions in alpine plants.