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

在北极，植物开始生长是在六月冬雪融化之后。当八月气温变冷时，它们就停止生长。北极的生长季节越往北越短，越往南越长。这导致它们的生长时间在不同种群的普通植物之间有所不同。由于气候变化，北极变暖的速度比更南部的地区更快，生长季节也越来越长。有些植物可能由于基因的原因而无法适应较长的生长季节。相反，其他人可能有允许他们改变的基因。我们在北极发现了这两种。这项研究将研究光照、温度和遗传学如何共同作用，以确定北极植物如何应对生长季节的变化。对于某些植物，我们将调整它们接受的光量，以观察植物的反应。我们将研究植物是否有基因，使他们保持活跃，如果生长季节的变化。这种方法将有助于了解这些植物是否会在未来更温暖的北极地区生长。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。来自德克萨斯大学埃尔帕索分校的大学生将帮助在阿拉斯加进行实地考察。植物物候学，或叶子开始、叶子死亡和开花的时间，是受气候变化影响最大的一个特征。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。我们小组以前的研究确定了北方和南方草丛棉草种群之间生长季节长度的显着差异。这一发现表明，该物种的物候是在遗传约束下。本项目将调查当地适应对草丛棉草及其两个竞争对手，矮桦和茶叶杨柳的物候的影响。这一假说认为，温度、光照和遗传因素的不同组合是造成北极地区物候差异的原因。这些控制的强度在不同环境中发现的种群之间会有所不同。田间和生长室实验将确定温度，光照和遗传对植物物候的作用。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。各种方法的结合将为北极地区植物对气候变化的反应提供一种统一的方法。这个项目将有更广泛的影响北极科学的强大传统，涉及北极领域的研究本科生的建设。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西班牙裔服务机构招募助理。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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.