GRiMeDB: a comprehensive global database of methane concentrations and fluxes in fluvial ecosystems with supporting physical and chemical information

The Global River Methane Database (GriMeDB) is a compilation of measurements of CH4 concentrations and fluxes for flowing water environments derived from publications, reports, data repositories, and other outlets between 1973 and 2021. Assembly of GRiMeDB was motivated by the goal of having a centralized, standardized resource to facilitate further studies of CH4 pattern and process in flowing water systems, upscaling efforts, and identification of tendencies in when, where, and how CH4 has been sampled in streams and rivers across the world. Thus, CH4 data are supported by concurrent observations (as available) of aquatic CO2, N2O, temperature, conductivity, pH, dissolved oxygen, nitrogen, phosphorus, organic carbon, and discharge, along with site data (latitude, longitude, elevation, and [as available]: stream order, elevation, channel slope, catchment size, and codes for distinct or disturbed channel types). GRiMeDB includes over 24,000 records of CH4 concentration and greater than 8,000 flux measurements from over 5,000 unique sites, most of which are resolved to the daily time scale.

全球河流甲烷数据库（Global River Methane Database, GriMeDB）是1973年至2021年间，从已发表文献、研究报告、数据仓储及其他渠道搜集的流水环境甲烷（CH4）浓度与通量实测数据汇编。构建该数据库的初衷在于打造一套集中化、标准化的共享资源，以推动流水系统中甲烷的模式与过程研究、尺度上推工作，并便于识别全球范围内溪流与河流中甲烷采样的时间、地点与实施方式特征。
因此，数据库收录的甲烷数据同步配套了可获取的水生二氧化碳（CO2）、一氧化二氮（N2O）、水温、电导率、pH值、溶解氧、氮、磷、有机碳及径流量等同步观测数据，同时包含采样位点信息：经纬度、海拔高度，以及（视可用情况提供的）河流等级、河道海拔、河道坡度、集水区面积，以及原生或受干扰河道类型的编码。
GriMeDB共收录超24000条甲烷浓度记录与8000余条通量实测记录，涉及5000余个独特采样位点，其中绝大多数数据的时间分辨率可达日尺度。