Modelling nutrient acquisition by crops with specific consideration of biopores

定量理解土壤结构、土壤养分库、根系结构和作物对底土的水分和养分吸收之间的相互作用，需要考虑包括芽生长、根系发育、土壤水分动力学和土壤养分周转在内的复杂过程。数学建模为定量描述植物-土壤系统中的水分和养分动态提供了有益的手段。该提案的中心假设是，模拟作物从底土中获取养分不仅要考虑作物类型及其特定的根系，还要考虑土壤结构，特别是生物孔。我们假设，考虑生物孔密度和质量以及土壤水分状况对底土养分周转和可及性的影响，将改善作物在田间尺度上养分获取的动态模拟模型，为未来改进农艺管理和作物提供更好的依据。特别强调氮和磷的获取与土壤水分条件和养分需求的相互作用。该项目采用双室方法，在SIMPLACE建模框架内开发了具体的子模型，用于土壤基质和土壤生物孔内氮和磷的周转和吸收。模型开发、校准和验证利用了在1320研究单元收集的数据和在协调bundle的其他四个项目中收集的数据。此外，在j<s:1> lich研究中心运行的高分辨率3D根系生长模型中，有关生物孔特性、根系结构和养分吸收影响的发现和算法将在开发现场规模模型解决方案时得到考虑。

Quantitative understanding of the interactions between soil structure, soil nutrient pools, root architecture and water and nutrient uptake from subsoils by crops requires approaches that consider the complexity of processes involved including shoot growth, root development, soil water dynamics and soil nutrient turnover. Mathematical modelling provides a helpful mean for the quantitative description of water and nutrient dynamics within the plant-soil system. The central hypothesis of the proposal is that the simulation of nutrient acquisition by crops from the subsoil has to take into account not only crop types with their specific root system, but also soil structure and in particular biopores. We hypothesize that the consideration of the effects of biopore density and quality as well as soil water status on nutrient turnover and accessibility in the subsoil will improve the dynamic simulation modelling of nutrient acquisition by crops at the field scale providing a better basis for improving agronomic management and crops in the future. Specific emphasis is on the acquisition of N and P in interaction with soil moisture conditions and nutrient demand. Using a two-compartment approach, the project develops specific submodels within the modelling framework SIMPLACE for the turnover and uptake of N and P within the soil matrix as well as in the soil biopores. Model development, calibration and validation takes advantage of data which have been collected within the research unit 1320 and data which are gathered in the four other projects of the concerted bundle.In addition, findings and algorithms regarding the influence of biopore properties, root architecture and nutrient uptake from a higher resolution 3D root growth model running at the research center Jülich will be considered in the development of the field scale model solution.