Workflow-based Spatial Modeling Environment and its application in food provisioning services of grassland ecosystem

Focusing on the topic of model integration, we develop a Workflow-based Spatial Modeling Environment (WF-SME) which enables scientists and modeling users easy to design and create of complex systems models through a drag-drop operation or editing mathematical formula in model constructor. WF-SME, a visual integrated modeling environment is mainly used for the rapid realization of model dynamic integration, in which we can implement the composition and connection of the existing models, and generate new model through graphical operation. The papers firstly introduce the framework of model integration designed for WF-SME as well as its supporting theory, and then explain in detail how the modules of WF-SME have been realized. WF-SME is a platform for spatial modelling, which was designed in four parts, Spatial Workflow Designer, Model builder, Spatial Calculation engine and Visualization of Modelling Output. The spatial workflow designer built-in WF-SME shipping with toolsets was adopted to create spatial workflow, reuse and aggregate models. Consisting of equation editor and data banding tool, the model builder enable modeller updates formulas on-demand. This editor parsed by MathML is powerful and flexible enough for the requirements of expressions of mathematical calculations. The spatial calculating engine developed based on component, through the map algebra language, executes mathematical calculations. The multi-form visualization module was developed to provide visual expression for a series of intermediate data and its result of the domain models. Finally, we illustrate how the typical practical application sample has been modeled in our modeling environment to validate the feasibility and efficiency of WF-SME. As a case study, grassland ecosystem productivity mechanism model whose input parameters include PAR (Photo synthetically active radiation), Temperature, Precipitation, Soil fertility etc, were build using WF-SME. By the experiments, it is shown that ou- - r research is a new attempt for model components reusing and complicated models integration, and WF-SME has been satisfied for complicatedly modeling in multi-domain of resource and environment.