In situ surface soil water content and precipitation dataset from a preserved Caatinga area in the Brazilian semi-arid region

This dataset provides continuous time series of in-situ soil moisture and precipitation collected over a six-year period (2015–2020) in a preserved area of the Caatinga biome, located in the Brazilian semiarid region at the Embrapa Semiárido experimental field in Petrolina, Pernambuco, Brazil. The dataset contains essential hydrological observations for investigating ecohydrological processes in seasonally dry tropical ecosystems. Soil moisture was measured in situ at a depth of 5 cm, representing volumetric soil water content (m³/m³). Measurements include daily averaged values and two fixed daily observations recorded at 6:00 AM and 18:00 local time. Precipitation data correspond to daily accumulated rainfall (mm), measured using a rain gauge installed within the same experimental area to ensure spatial consistency between variables. Data are provided in a single CSV (comma separated values) file structured according to international formatting standards: comma-separated fields, decimal point, and dates in ISO 8601 format (YYYY-MM-DD). Each row represents one day of observation. Althought the dataset was primarily developed to support the validation of satellite-derived soil moisture products, its applicability extends to multiple research fields, including hydrology, remote sensing, ecology, hydrological modeling, climate change studies, and water resource management in semiarid environments. By making these measurements publicy available, this dataset contributes to reducing the scarcity of long term in situ observations from preserved Caatinga areas, a biome that remains underrepresented in global hydrological databases.

本数据集提供了巴西半干旱地区卡廷加（Caatinga）生物群落保护区内为期六年（2015–2020年）的原位土壤湿度与降水连续时间序列数据，采集点位位于巴西伯南布哥州佩特罗利纳市的巴西农牧业研究公司半干旱实验场（Embrapa Semiárido）。该数据集包含支撑季节性干旱热带生态系统生态水文过程研究的关键水文观测数据。土壤湿度于5 cm深度原位测定，表征体积土壤含水量（单位：m³/m³）。观测数据包含日平均值，以及当地时间每日6:00与18:00的两次固定时段观测值。降水数据为日累积降雨量（单位：mm），通过安装于同一实验区域内的雨量计测定，以保障各变量间的空间一致性。数据以单个CSV（逗号分隔值）文件提供，遵循国际格式标准：字段以逗号分隔、采用小数点作为小数分隔符，日期格式符合ISO 8601标准（YYYY-MM-DD）。每一行代表单日观测数据。尽管该数据集最初主要用于支撑卫星反演土壤湿度产品的验证工作，但其适用范围可拓展至多个研究领域，包括水文学、遥感、生态学、水文建模、气候变化研究，以及半干旱环境下的水资源管理。通过公开共享这些观测数据，本数据集有助于缓解全球水文数据库中受保护卡廷加生物群落区域长期原位观测数据匮乏的现状——该生物群落在全球水文数据库中的占比仍处于较低水平。