Integrated Hydrological Units of the United Kingdom: Groups

This dataset is part of Integrated Hydrological Units (IHU) of the UK, a set of geographical reference units for hydrological purposes including river flow measurement and hydrometric data collection. Groups represent the intermediate units of IHU in terms of spatial resolution. The most common size of a group is around 400 square kilometres. Each Group carries a name constructed from names of the major river flowing through the Group, the major river flowing into the Group, the major river into which the Group flows, and sometimes also from local county names. Each Group consists of one or more Section and Groups can be combined to form Hydrometric Areas without Coastline. Identifiers and attributes have been calculated so that direct upstream and direct downstream IHU units can be selected. This layer currently covers Great Britain only as no dataset with river geometries and names with suitable detail is available for Northern Ireland. Full details about this dataset can be found at https://doi.org/10.5285/f1cd5e33-2633-4304-bbc2-b8d34711d902本数据集属于英国综合水文单元（Integrated Hydrological Units, IHU）体系，是一类服务于水文工作的地理参考单元，可用于河流流量测量与水文数据采集。按空间分辨率划分，分组（Group）为综合水文单元的中间层级单元，单个分组的常见规模约为400平方千米。每个分组的名称由流经该分组的主要河流、汇入该分组的主要河流、该分组水流汇入的主要河流名称构成，部分分组还会加入当地郡名以完善命名。每个分组包含一个或多个区段（Section），多个分组可合并为无海岸线水文区域。已计算生成标识符与属性信息，可据此快速筛选直接上游与直接下游的综合水文单元。当前该图层仅覆盖大不列颠地区，因北爱尔兰暂无具备足够详细的河流几何形态与名称信息的可用数据集。本数据集的完整详情可访问：https://doi.org/10.5285/f1cd5e33-2633-4304-bbc2-b8d34711d902