Soil invertebrates under global change

群落和生态系统正日益受到全球变化的影响，但我们对陆地生态系统中这些影响的理解大多是基于地上生物。相比之下，尽管土壤高度多样化，并支持许多关键的生态系统功能，如碳循环，但我们对地下全球变化的影响，特别是影响如何在时空尺度上变化的了解有限。我的研究重点是利用实地观察、实验、建模和数据合成的组合来解决我们知识中的这一差距。在我的研究中，我使用蚯蚓作为模型群，因为它们扮演着生态系统工程师的角色，可能对其他生物产生巨大影响，而且许多物种已经入侵了新的地区。我和我的学生将研究以下关键问题：1)土壤无脊椎动物如何分布在多个空间尺度上，全球变化将如何改变这种分布？随着时间的推移，我们将研究全球变化对蚯蚓生物多样性的影响，以及对非本地蚯蚓物种分布的影响。我们还将研究气候、栖息地和人类活动在确定非本地蚯蚓北部分布中的相对重要性，并利用这些信息来模拟潜在的未来分布。2)全球变化如何直接和间接影响土壤中物种相互作用和群落组成？我们将测试气候变暖导致的植物群落变化（如灌木扩张）如何影响北方生态系统中土壤无脊椎动物群落和凋落物分解。3)物种分布和群落的变化如何影响生态系统功能？我们将研究由于全球变化而发生的土壤大型动物群落的变化如何影响微生物呼吸等生态系统功能。本项目将培养5名本科生、3名研究生和1名博士后。此外，一个公民科学项目将为公众提供直接参与这项研究的机会。这项研究的出版物将为全球变化如何影响土壤群落和生态系统功能，以及生物多样性和入侵理论如何应用于地下系统提供关键见解。

Communities and ecosystems are increasingly being impacted by global change but much of our understanding of these impacts in terrestrial ecosystems is based on aboveground organisms. In contrast, although soils are highly diverse and support many key ecosystem functions such as carbon cycling, we have a limited understanding of global change impacts belowground and in particular how impacts vary across spatial and temporal scales. My research focuses on addressing this gap in our knowledge using a combination of field observations, experiments, modelling, and data synthesis. I use earthworms as a model group in my research because they act as ecosystem engineers with the potential for large impacts on other organisms and because many species have invaded new regions. My students and I will investigate the following key questions: 1) How are soil invertebrates distributed across multiple spatial scales and how will this be altered by global change? We will examine effects of global change on earthworm biodiversity over time, and on distributions of non-native earthworm species. We will also investigate the relative importance of climate, habitat, and human activity in determining northern distributions of non-native earthworms and use this information to model potential future distributions. 2) How does global change directly and indirectly impact species interactions and community composition in the soil? We will test how changes in plant communities (e.g., shrub expansion) due to climate warming affect soil invertebrate communities and litter decomposition in northern ecosystems. 3) How do changes in species distributions and communities impact ecosystem functioning? We will examine how shifts in soil macrofauna communities occurring as a result of global change affect ecosystem functions such as microbial respiration. Five undergraduate students, three graduate students, and one postdoctoral fellow will be trained during the course of this grant. In addition, a citizen science project will provide the public with the opportunity to directly participate in this research. Publications from this research will provide key insights into how global change affects soil communities and ecosystem functioning, as well as how biodiversity and invasion theories apply to belowground systems.