Root and mycorrhizal responses to nutrient additions in a tropical mountain forest and in pastures after forest conversion

热带山地森林和森林转变后牧场的根和菌根对养分添加的反应

• 批准号: 162628199
• 负责人: Professor Dr. Matthias C. Rillig, Ph.D.
• 金额: --
• 依托单位: Arbeitsgruppe Ökologie der Pflanzen
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/162628199?language=en
• 关键词: Root; mycorrhizal; responses; nutrient; additions

The goal of this project is to enhance the comparatively poor knowledge about arbuscular mycorrhizas (AM) and roots in tropical mountain forest systems in general, and in particular to integrate mycorrhizal responses into ongoing nutrient manipulations (NUMEX in the forest and FERFAST in the pasture) of the Research Unit. Within this framework, we ask questions about the abundance of AM fungi in roots and in the soil (extraradical hyphae), hypothesizing that even low levels of fertilization will cause decreased mycorrhizal fungal abundance. We also hypothesize that there are tradeoffs between extraradical AM hyphal abundance and fine roots, two structures with partially overlapping functions. Using molecular ecology tools (pyrosequencing and terminal restriction fragment length polymorphism analysis) we test for differences in AM fungal assemblages in the soil in response to nutrient manipulations and along an elevation gradient. Integrating both potential abundance and assemblage composition changes of AM fungi, we finally ask the pivotal question if fertilization can favor the occurrence of less mutualistic AM fungal assemblages. This will be accomplished using a greenhouse inoculation approach. One of the mycorrhizal functions examined will be plant growth, but we will also examine the ecosystem process of soil aggregation.

该项目的目标是提高对一般热带山地森林系统中丛枝菌根（AM）和根系的相对贫乏的知识，特别是将菌根反应纳入研究单位正在进行的营养操作（森林中的NUMEX和牧场中的FERFAST）。在这个框架内，我们问的问题，丰富的AM真菌在根和土壤中（根外菌丝），假设即使是低水平的施肥会导致减少菌根真菌丰度。我们还假设根外AM菌丝丰度和细根（两种功能部分重叠的结构）之间存在权衡。使用分子生态学工具（焦磷酸测序和末端限制性片段长度多态性分析），我们测试的差异AM真菌组合在土壤中的营养操作和沿着海拔梯度。结合潜在的丰富度和AM真菌组合组成的变化，我们最后问的关键问题，如果施肥可以有利于发生较少的互利共生AM真菌组合。这将使用温室接种方法完成。菌根的功能之一是植物生长，但我们也将研究土壤聚集的生态系统过程。