Experimental determination of energy and matter exchange processes and their modelling on stand scale

在这一分项目内，将通过实验和模拟活动调查林分规模上的物理和部分化学过程。计划在夏季、秋季、冬季和春季进行不同的实验，并在森林中进行长期观测计划，以观测以下过程：平流、湍流结构、气象和化学量的通量梯度、边界层。将使用涡旋协方差和不同的能量和物质通量(包括痕量气体和同位素)REA技术。所有数据，特别是通量数据，都是用最近开发的工具(与为CarboEuroFlux开发的类似)进行质量控制的。将根据足迹、QA/QC以及中、微尺度气象条件，为状态变量和高阶矩创建概率密度函数。将继续目前使用小波分析来研究相干结构，并使用有条件的样本工具进行更多的定量研究，并确定对强迫参数的影响，以便对火焰模型(森林-土地-大气模型)的传递矩阵进行更广泛的参数化。火焰实际上是用来模拟标准尺度上的交换过程的。在项目的第一阶段，应用1D/2D版本，结合详细的土壤-植物模型，预测详细的林分水文、生理和平流对水、能量和痕量物质循环的影响。将研究对外部和内部压力的敏感性。状态变量和湍动矩的PDF将与实验结果进行比较，并扩展到景观尺度上的应用。3D版本的开发--第一次在林分尺度上--还需要开发和评估3D瞬变理论，以描述从森林地面到大气边界层顶部的湍流和对流混合。根据使用气象数据以及二氧化碳和水蒸气通量的BayCEER监测方案(http://www.bayceer.uni-bayreuth.de/)，)，将为所有次级项目提供相关数据，重点主要放在建模和遥感部分。

Within this sub-project the physical and partly also chemical processes on the stand scale will be investigated by experimental and modelling activities. Different experiments for summer, autumn, winter, and spring and a long term observing programme in the forest are planned to observe the following processes: advection, turbulence structure, flux gradients of meteorological and chemical quantities, boundary layer. Eddy-covariance and different REA techniques for energy and matter fluxes (including trace gases and isotopes) will be used. All data and especially the flux data are quality controlled with recently developed tools (similar as developed for CarboEuroflux). Pdfs (probability density functions) will be created for state variables and higher moments on the basis of the footprint, QA/QC and the meso- and microscale meteorological conditions. The current use of wavelet analysis to investigate coherent structures will be continued with conditional sample tools to be employed for more quantitative investigations and for determining the influence on forcing parameters to develop a more extended parameterization of the transilient matrix of the FLAME model (Forest-Land-Atmosphere Model). FLAME is actually applied to model exchange processes on the stand scale. In the first phase of the project, the 1D/2D-version, coupled to a detailed soil-plant model, is applied to predict the influences of detailed stand hydrology, physiology and advection on the cycles of water, energy, and trace substances. The sensitivity towards external and internal forcings will be studied. Pdfs for state variables and turbulent moments will be compared to those from experiments and extended for the application on landscape scale. The development of a 3D-version – first on stand scale – also requires the development and evaluation of the 3D transilient theory to describe the turbulent and convective mixing from the forest floor to the top of the atmospheric boundary layer. Based on the BayCEER monitoring programme with meteorological data und carbon dioxide and water vapour fluxes (http://www.bayceer.uni-bayreuth.de/), the relevant data will be made available for all sub-projects, with a focus on mainly on the modelling and remote sensing parts.