Collaborative Research: Plant phenology, local adaptation, and growing season length in the changing Arctic tundra

在北极，植物在6月份冬季积雪融化后开始生长。当8月份气温回升时，它们就会停止生长。北极的生长季越往北越短，向南越长。这导致它们的生长时间在不同的常见植物种群之间有所不同。由于气候变化，北极变暖的速度比更靠南的地区更快，生长季也越来越长。由于基因的原因，一些植物可能无法适应较长的生长季。相比之下，其他人可能拥有允许他们改变的基因。我们在北极发现了这两种生物。这项研究将研究光、温度和遗传学如何共同作用，以确定北极植物如何对生长季节的变化做出反应。对于一些植物，我们将调整它们接收的光量，看看植物如何反应。我们将研究这些植物是否有基因允许它们在生长季节改变时保持活跃。这种方法将有助于了解这些植物是否会在未来变暖的北极生长。为了帮助在阿拉斯加工作的科学家，宾夕法尼亚州的高中生将在实验室里种植北极植物，看看它们对光线变化的反应。德克萨斯大学埃尔帕索分校的大学生将帮助阿拉斯加的田野工作。植物物候，或叶片开始、死亡和开花的时间，是受气候变化影响最大的特征之一。在北极，植物物候的变化可以在多个层面上改变生态系统的功能。我们课题组之前的研究发现，北部和南部种群的棉铃草在生长季长度上存在显著差异。这一发现表明，该物种的物候学受到遗传限制。本项目将研究当地适应对棉铃草及其两种竞争对手--矮化桦树和茶柳树物候的影响。假设是温度、光照和遗传在不同的组合中，导致了北极地区物候的差异。这些控制的力度将因不同环境中的人口而有所不同。田间和生长室实验将确定温度、光照和遗传学在植物物候学上的作用。我们将在叶和生态系统尺度上监测植物，以了解物候和生长季节长度如何影响植物功能和生态系统响应。多种方法的结合将为北极地区的植物应对气候变化提供统一的方法。这个项目将通过建立让本科生参与北极实地研究的强大传统，对北极科学产生更广泛的影响。该项目将从一所拥有许多第一代学生的小型大学和一家领先的拉美裔服务机构招聘助理。该奖项反映了NSF的法定使命，通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为是值得支持的。

In the Arctic, plants begin their growth after winter snow melts in June. They stop growing when cold temperatures return in August. The growing season in the Arctic is shorter further north and longer towards the south. This causes the timing of their growth to vary between different populations of common plants. Because of climate change, the Arctic is getting warmer faster than areas that are further south, and the growing season is getting longer. Some plants may not adjust to the longer growing season because of their genes. In contrast, others may have genes that permit them to change. We find both kinds in the Arctic. This research will examine how light, temperature, and genetics work together to determine how arctic plants respond to changes in the growing season. For some plants, we will adjust the amount of light they receive to see how the plants respond. We will study if the plants have genes that allow them to stay active if the growing season changes. This approach will help to understand whether the plants will grow in a future warmer Arctic. To help the scientists working in Alaska, high school students in Pennsylvania will grow arctic plants in a laboratory to see how they respond to changes in light. College students from the University of Texas at El Paso will help with fieldwork in Alaska.Plant phenology, or the timing of leaf initiation, leaf death, and flowering, is one trait most affected by climate change. In the Arctic, changes in plant phenology can alter how ecosystems function at multiple levels. Previous research by our group identified a significant difference in growing season length between northern and southern populations of tussock cottongrass. This finding suggests that the phenology of this species is under genetic constraint. The present project will investigate the effect of local adaptation on the phenology of tussock cottongrass and two of its competitors, the dwarf birch and tealeaf willow. The hypothesis is that temperature, light, and genetics, in different combinations, are responsible for differences in phenology in the Arctic. The strength of these controls will vary between populations that are found in different environments. Field and growth chamber experiments will determine the role of temperature, light, and genetics on plant phenology. We will monitor plants at the leaf and ecosystem scales to understand how phenology and growing season length affect plant function and ecosystem responses. A combination of methods will provide a unified approach to plant response to climate change in the Arctic. This project will have broader impacts on arctic science by building on a strong tradition that involves undergraduates in arctic field research. The project will recruit assistants from a small university with many first-generation students and from a leading Hispanic Serving Institution. It will also involve high school students from Wilkes-Barre in laboratory studies of phenology.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.