Carbon input and turnover in subsoil biopores

碳(C)输入到底土中，特别是生物孔的重要性仍不清楚。该项目的目的是评估生物孔对不同作物的C运输和C向地下的周转的贡献，这取决于具有不同根系的作物。将详细研究不同来源(蚯蚓来源、根来源和混合来源)的生物孔道的生化特性。碳在不同来源的生物孔中的周转将通过培养和二氧化碳分析来研究。在作物序列实验(CeFiT)中，根据根系和生物孔密度的不同，将通过13C标记来估计进入底土的C输入。将用13C-PLFA分析生物孔内外微生物群对根际沉积物的利用。生物孔周围的酶活性分布将通过最近开发的土壤酶谱来测量。在受控条件下，将用~(14)C脉冲标记和成像来分析前茬作物的生物孔形成及其在主要作物中的利用。生物孔内和生物孔外的根的菌丝化作用将在CeFiT实验中进行分析，并与土壤深度有关，具体取决于表层的水分和养分含量。在这些研究的基础上，我们将量化生物孔对C运输和C周转的重要性，以及对底土中微生物活动的重要性，取决于以前的作物。

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.