Collaborative Research: Interactions Between Plant Chemicals and Microbial Communities through Forest Succession in the Alaskan Taiga

这项拟议的研究调查了植物化学投入对阿拉斯加泰加森林土壤微生物过程的影响。研究将集中在赤杨和香脂杨产生的单宁，这两个物种构成了阿拉斯加泛滥平原森林演替序列的一部分。不同化学结构的单宁将从这些物种中分离出来，并添加到赤杨和杨树的土壤中。将测量它们对一系列微生物过程的影响，包括呼吸作用、氮矿化和酶活性。这些化学物质的具体结构将与其生物活性联系起来，以提高我们对这些化学物质的生态功能的了解。单宁将从每个物种应用到每个土壤中，以确定微生物群落是否能够适应进入土壤的化学物质。这些研究将极大地提高我们对植物如何影响土壤过程的理解，土壤过程控制着养分的可获得性，从而控制着阿拉斯加针叶林的植物演替。我们将提高对森林群落动态、对凋落物质量和分解的控制、植物与微生物的相互作用以及微生物群落组成在生态系统功能中的作用的理解。

The proposed research investigates the impact of plant chemical inputs on soil microbial processes in the Alaskan taiga forest. Studies will focus on tannins produced by alder and balsam poplar, two species that form part of the successional sequence in the floodplain forests of Alaska. Tannins of varying chemical structure will be isolated from these species and added to soils from both alder and poplar sites. Their effects on a suite of microbial processes including respiration, nitrogen mineralization, and enzyme activities will be measured. The specific structure of the chemicals will be linked with their biological activities to improve our understanding of the ecological function of these chemicals. Tannins will be applied from each species to each soil to determine whether the microbial communities can adapt to the chemicals coming in. These studies will greatly improve our understanding of how plants affect the soil processes that control nutrient availability and therefore plant succession in the Alaskan taiga. We will improve our understanding of forest community dynamics, controls on litter quality and decomposition, plant-microbe interactions, and the role of microbial community composition in ecosystem function.