Seitz Taylor J, Schütte Ursel M E, Drown Devin M
Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK, United States.
Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, United States.
Front Microbiol. 2021 Feb 1;12:619711. doi: 10.3389/fmicb.2021.619711. eCollection 2021.
Recent advances in climate research have discovered that permafrost is particularly vulnerable to the changes occurring in the atmosphere and climate, especially in Alaska where 85% of the land is underlain by mostly discontinuous permafrost. As permafrost thaws, research has shown that natural and anthropogenic soil disturbance causes microbial communities to undergo shifts in membership composition and biomass, as well as in functional diversity. Boreal forests are home to many plants that are integral to the subsistence diets of many Alaska Native communities. Yet, it is unclear how the observed shifts in soil microbes can affect above ground plant communities that are relied on as a major source of food. In this study, we tested the hypothesis that microbial communities associated with permafrost thaw affect plant productivity by growing five plant species found in Boreal forests and Tundra ecosystems, including low-bush cranberry and bog blueberry, with microbial communities from the active layer soils of a permafrost thaw gradient. We found that plant productivity was significantly affected by the microbial soil inoculants. Plants inoculated with communities from above thawing permafrost showed decreased productivity compared to plants inoculated with microbes from undisturbed soils. We used metagenomic sequencing to determine that microbial communities from disturbed soils above thawing permafrost differ in taxonomy from microbial communities in undisturbed soils above intact permafrost. The combination of these results indicates that a decrease in plant productivity can be linked to soil disturbance driven changes in microbial community membership and abundance. These data contribute to an understanding of how microbial communities can be affected by soil disturbance and climate change, and how those community shifts can further influence plant productivity in Boreal forests and more broadly, ecosystem health.
气候研究的最新进展发现，永久冻土特别容易受到大气和气候中发生的变化的影响，尤其是在阿拉斯加，那里85%的土地下面是大多不连续的永久冻土。研究表明，随着永久冻土解冻，自然和人为的土壤扰动会导致微生物群落的成员组成、生物量以及功能多样性发生变化。北方森林中有许多植物，它们是许多阿拉斯加原住民社区生存饮食中不可或缺的一部分。然而，目前尚不清楚观察到的土壤微生物变化如何影响作为主要食物来源的地上植物群落。在这项研究中，我们通过种植北方森林和苔原生态系统中发现的五种植物，包括矮蔓越莓和沼泽蓝莓，并使用来自永久冻土解冻梯度活跃层土壤的微生物群落，来检验与永久冻土解冻相关的微生物群落影响植物生产力的假设。我们发现植物生产力受到土壤微生物接种剂的显著影响。与接种未受干扰土壤中微生物的植物相比，接种解冻永久冻土以上区域群落的植物生产力下降。我们使用宏基因组测序来确定，解冻永久冻土以上受干扰土壤中的微生物群落与完整永久冻土以上未受干扰土壤中的微生物群落在分类学上存在差异。这些结果共同表明，植物生产力的下降可能与土壤扰动驱动的微生物群落成员和丰度变化有关。这些数据有助于理解微生物群落如何受到土壤扰动和气候变化的影响，以及这些群落变化如何进一步影响北方森林中的植物生产力，更广泛地说，影响生态系统健康。
