Measuring and modelling of plant effects on denitrification using innovative techniques

项目P7“利用创新技术测量和模拟植物对反硝化的影响”将在DASIM第一阶段使用新开发的植物-土壤-培养箱，以进一步表征根际植物-微生物相互作用对反硝化和土壤中通过反硝化(NO、N2O、N2)产生N气体的重要性。除了迄今使用的氦(He)气体流动技术之外，我们还将首次测试先进的拉曼光谱技术在“标准”大气组成条件下(约20%O2/80%n2)用于氮气产生测量的适用性。虽然这将需要光子技术的进一步发展，但我们非常肯定，这种新的技术方法将为我们直接测量土壤中土壤-植物反硝化动态的能力提供新的见解和科学突破。我们假设植物光合作用和根际反硝化作用通过根分泌物紧密耦合，关系尚未量化。将与DASIM的所有合作伙伴密切合作，进行实验室和田间蒸渗仪实验(野外条件下大型完整土芯的全氮平衡)。自己的实验结果以及DASIM合作伙伴的实验和建模结果将用于进一步开发生物地球化学模型Landscape DNDC的反硝化和土壤水文/物理子模块。该模型将用于测试当前开发的各种DASIM模型方法，并用于扩展结果

The project P7 „Measuring and modelling of plant effects on denitrification using innovative techniques” will use the newly, in DASIM Phase I developed plant-soil-incubation chamber for further characterizing the significance of rhizosphere plant-micro-organism interactions for denitrification and N gas production via denitrification (NO, N2O, N2) in soils. In addition to the so far used Helium (He) gas flow technique, which is based on the headspace gas exchange with a N2 free atmosphere mixture of He and O2 to allow for N2 production, we will for the first time test the suitability of advanced Raman spectroscopy for N2 production measurements under “standard” atmospheric composition conditions (ca. 20% O2/ 80% N2). Though this will require further developments of the photonic technology, we are very positive that this new technological approach will offer new insights and a scientific breakthrough in our capability to measure soil-plant denitrification dynamics in soils directly.We hypothesize that plant photosynthesis and rhizosphere denitrification are closely coupled via root exudation, with relationships not being quantified yet. Laboratory and field-lysimeter experiments (total N balance of large intact soil cores under field condition) will be executed in close cooperation with all DASIM partners. Results of own experiments as well as experimental and modelling results of DASIM partners will be used for the further development of the denitrification and soil hydrology/physics submodules of the biogeochemical model LandscapeDNDC. This model will be used for testing various currently developed DASIM model approaches and for scaling resul