Carbon input and turnover in subsoil biopores

碳（C）输入到底土，特别是生物孔隙的重要性仍然不清楚。本项目的目的是评估生物孔隙的碳运输和碳周转到底土取决于作物与对比根系的贡献。将详细研究各种来源（蚯蚓来源、根来源和混合来源）的生物孔隙的生物化学性质。将通过培养和CO2分析研究各种来源的生物孔隙中的C周转。C输入到底土取决于根系和生物孔密度将估计作物序列实验（CeFiT）中的13 C标记。利用13 C-PLFA分析了生物孔隙内外微生物类群对根际沉积物的利用。生物孔隙周围酶活性的分布将通过最近开发的土壤酶谱法来测量。在受控条件下，将通过14 C脉冲标记和成像来分析前茬作物的生物孔形成及其被主要作物的利用。在CeFiT实验中，我们将分析根在生物孔隙内外的菌根化，并根据表层土壤的水分和养分含量与土壤深度相关。基于这些研究，我们将量化生物孔隙对碳运输和碳周转以及对底土中微生物活动的重要性，这取决于前茬作物。

The carbon (C) input into the subsoil and especially the importance of biopores remains unclear. The aim of this project is to evaluate the contribution of biopores to the C transport and C turnover into the subsoil depending on crops with contrasting root systems. Biochemical properties of biopores of various origins (earthworm-derived, root-derived and mixed) will be studied in detail. C turnover in biopores of various origins will be studied by incubation and CO2 analysis. C input into the subsoil depending on the root system and on biopore density will be estimated by 13C labeling in the crop sequence experiment (CeFiT). The utilization of rhizodeposits by microbial groups in and out of biopores will be analyzed by 13C-PLFA. The distribution of enzyme activities around the biopores will be measured by recently developed soil zymography. The biopore formation by preceding crops and their use by main crops will be analyzed by 14C pulse labeling and imaging under controlled conditions. Mycorrhization of roots in and out of biopores will be analyzed in the CeFiT experiment and related to soil depths, depending on moisture and nutrient contents of the topsoil.Based on these studies, we will quantify the importance of biopores for C transport and C turnover and for microbial activity in the subsoil depending on preceding crops.