Virtual Hydrologic Environment (VHE) - as a bridge between surface and subsurface hydrology

应开发一个虚拟水文环境(VHE)，以缩小目前地表和地下水文模型之间的差距。VHE是发生在水文系统(HS)中的物理过程的通用表示。HS可细分为地表水以及土壤和含水层隔层中的水(图1)，它们构成了地下系统。其内部相应的水文过程是地表的水流过程，如湖泊、河流和地表水流，土壤中的水流过程，如土壤中的非饱和渗流，以及多孔和裂隙介质中的地下水流动。VHE被定义为集成的数据和模型环境。与以数据为中心的地理信息系统(GIS)或基于物理过程的数值模拟器相比，VHE具有以通用的可理解的地质水文/数据库(GH/DB)结构存储地质和水文信息的能力。GH/DB将以一致的方式包含地表和次表层的数据组成部分，这是以前没有实现的，因为通常在水文数据库和建模中只分别考虑这两个部分。此外，VHE可以与地理信息系统软件和遥感技术的能力相结合，并促进与数值模型的集成，例如本项目计划使用的基于物理的水文模拟器GEOsys/RockFlow。由于内在的耦合过程使水文相互作用难以模拟，因此鼓励采用多学科方法，通过与其他相关科学的整合和跨学科交叉交流，拓宽水文视角，推动水文科学的发展。VHE作为连接地表和地下水文学的桥梁，可以加深我们对水循环、水、地球、生态系统和人类之间的相互作用及其在气候变化背景下的作用的理解。这是一项跨学科的研究建议，涉及以下学科：地理学、水文学、地质学、科学计算和信息技术。利用科学计算和信息技术的方法集成不同地球科学的数据库和模型，将使水系在水文模拟中得到全面和一致的表达，从而加深我们对水系不同区段之间的相互作用和耦合过程的理解。这项研究计划将中国最大的淡水湖--鄱阳湖作为一个国际合作框架的应用领域。

A Virtual Hydrologic Environment (VHE) shall be developed to close the current gap between surface and subsurface hydrological modelling. A VHE is a generic representation of the physical processes that take place in the hydrological system (HS). The HS can be subdivided into surface water as well as water in soil and aquifer compartments (Fig 1) which form the subsurface system. The corresponding hydrological processes inside a HS are flow processes at the surface, like lakes, rivers and overland flow, flow processes in the soil, like unsaturated flow in soils and groundwater flow in porous and fractured media. The VHE is defined as an integrated data and model environment. Compared with the data-centred Geographic Information Systems (GIS) or physical process based numerical simulators, VHE has the ability to store geological and hydrological information in a common understandable GeoHydro/DataBase (GH/DB) structure. The GH/DB will contain the data components of the surface and subsurface in a consistent manner, which has not been achieved before as commonly both parts were only considered separately in hydrological databases and modelling. In addition, VHE can be combined with the capabilities of GIS software and remote sensing technology and facilitates the integration with numerical models, e.g. physics-based hydrological simulator GeoSys/RockFlow as it is planned for the present project. As the inherent coupled processes make the hydrologic interactions difficult to simulate, a multi-disciplinary approach is encouraged that enables a broadening of the hydrologic perspective and the advancement of hydrologic science through the integration with other related sciences and the through cross-fertilization across disciplinary boundaries. VHE as a bridge between surface and subsurface hydrology can improve our understanding of the hydrologic cycle, the interactions between water, earth, ecosystems and man and its role in the context of climate change. This is an interdisciplinary research proposal, and the following disciplines are involved: geography, hydrology, geology, scientific computing, and information technology. The proposed integration of databases and modeling from the different geo-sciences by the use of methods from scientific computing and information technology will lead to a comprehensive and consistent representation of the HS in hydrological modeling, and thus will enhance our understanding about the interactions and coupling processes between the different compartments of the HS. This research program plans to take Poyang Lake, the biggest freshwater lake in China, as an application area in an internatiopnal collaborative framework.