Lipid and PAH composition as indicators for conditions of thermal degradation

脂类是土壤和沉积物中新鲜植物生物量和有机质的主要成分。个别植物和植物群携带特定的脂质分布模式，这使得它们可以作为生物标志物应用。植物生物量的热降解，即在人为或野火期间，根据燃烧条件改变了分布模式。因此，燃烧条件可以重建的基础上的模式的主要成分，如醇和酸，以及它们的降解产物，包括脂肪族和多环芳烃（PAHs）。将对土壤和沉积物中就地掺入的烧焦生物量进行生物标志物分析。在一个实验中，温度，持续时间和氧的可用性在热降解过程中对几种植物的脂质分布模式的修改的影响将进行调查。实验结果进行了比较，最近和化石土壤和沉积物中含有烧焦的生物质。由于频繁的燃烧和众所周知的燃烧历史，选择了近代土壤，而古代土壤则根据考古文物选择了已知燃烧历史。该项目的成果首次通过土壤和沉积物中烧焦物质的脂质组成，促进了自然和生物改良生态系统中火灾条件和植被的重建。

Lipids are main components of fresh plant biomass and organic matter in soils and sediments. Individual plants and plant groups carry a specific lipid distribution pattern which allows for their application as biomarkers. Thermal degradation of plant biomass i.e. during anthropogenic or wildfires shifts the distribution patterns depending on burning conditions. Therefore, burning conditions may be reconstructed based on patterns of primary lipidic components like alcohols and acids as well as their degradation products including aliphatic and polycyclic aromatic hydrocarbons (PAHs). Charred biomass incorporated in situ in soils and sediments will be subjected to biomarker analyses. Within an experiment the influence of temperature, duration, and oxygen availability during thermal degradation on modification of lipid distribution patterns of several plant species will be investigated. Experimental results are compared to recent and fossil soils and sediments containing charred biomass. Recent soils are selected due to frequent burning and well known burning history, whereas ancient soils are selected with a known burning history based on archaeological artefacts. The results of the project facilitate for the first time the reconstruction of fire conditions and vegetation in natural and anthropogenically modified ecosystems by means of lipid composition of charred materials from soils and sediments.