HYDROMED : Physical & biogeochemical dataset for North-Western Mediterranean Stations

HDROMED is a curated dataset built by aggregating and filtering already publicly available data. For a selection of physico-chemical parameters, the resulting dataset only contains measurements where all parameters meet minimal quality requirements. Moreover, only surface measurements for stations located in the north-western Mediterranean area and collected from january 2000 on are considered.
The Jupyter Notebook used to build the dataset is available at https://gitlab.sb-roscoff.fr/future-obs/wp5/hydrochimie-cotier-med
Parameter list
The following parameters are included in the output dataset.
- Temperature
- Salinity
- Nitrates
- Nitrites
- Ammonium
- Phosphates
- Silicates
- Chlorophyll a
Source Datasets
Two datasets have been selected as primary sources for measurement data:
- The dataset provided by the SOMLIT French National Observation Service, and available at https://doi.org/10.17882/100323
- The dataset provided by the REPHY network, and available at https://doi.org/10.12770/cf5048f6-5bbf-4e44-ba74-e6f429af51ea
Output Dataset
The output dataset columns are defined as follows:
- SITE : the name of the sampling location
- DATE : the sampling date
- LATITUDE : the latitude of the sampling location
- LONGITUDE : the longitude of the sampling location
Then, for each parameter, three columns are defined, the first one with the actual parameter value, the second one with the quality flag associated to the value, and the third one with a comment relative to the parameter. For the temperature parameter, the columns will be named as follows : T, T_QUALITY, T_COMMENTS.
Some parameters need special attention :
An additional NO2+NO3 parameter is included, as for some measurements no separate values are provided for NO2 and NO3, only the sum of both.
Due to the variety of methods for measuring Chlorophyll A, columns had to be defined reflecting the measurement method :
- CHLASPECTRO : Chlorphyll A measured using spectrometry
- CHLAHPLC : Chlorophyll A measured using liquid chromatography
- CHLAFLUO : Chlorophyll A measured using fluorimetry
- DVCHLA : Divynil Chlorophyll A
Finally, to more columns are added to explicit measurement provenance:
- SOURCE : Either SOMLIT or REPHY
- DOI : The DOI of the landing page where the original dataset was downloaded.

HDROMED是一套经精心整合并筛选公开现有数据构建的精选数据集。针对选定的理化参数（physico-chemical parameters），最终数据集仅保留所有参数均满足最低质量要求的测量结果。此外，仅纳入2000年1月起采集的地中海西北部海域监测站点的表层测量数据。
用于构建该数据集的Jupyter Notebook（交互式编程笔记本）可于https://gitlab.sb-roscoff.fr/future-obs/wp5/hydrochimie-cotier-med获取。
### 参数清单
本输出数据集包含以下参数：
- 水温（Temperature）
- 盐度（Salinity）
- 硝酸盐（Nitrates）
- 亚硝酸盐（Nitrites）
- 铵态氮（Ammonium）
- 磷酸盐（Phosphates）
- 硅酸盐（Silicates）
- 叶绿素a（Chlorophyll a）
### 源数据集
本测量数据的核心来源为两套公开数据集：
- 法国国家观测服务机构SOMLIT提供的数据集，可通过https://doi.org/10.17882/100323获取
- REPHY网络提供的数据集，可通过https://doi.org/10.12770/cf5048f6-5bbf-4e44-ba74-e6f429af51ea获取
### 输出数据集
输出数据集的列定义如下：
- SITE：采样点位名称
- DATE：采样日期
- LATITUDE：采样点位纬度
- LONGITUDE：采样点位经度
针对每个参数，均设置三列：第一列为参数实际测量值，第二列为对应测量值的质量标记，第三列为该参数的相关注释。以水温（Temperature）参数为例，其对应列将命名为：T、T_QUALITY、T_COMMENTS。
### 特殊参数说明
部分参数需进行特殊处理：
增设NO2+NO3参数：因部分测量未单独提供亚硝酸盐（Nitrites）与硝酸盐（Nitrates）的数值，仅给出二者的总和。
鉴于叶绿素a（Chlorophyll a）的测量方法存在多样性，需设置对应列以明确测量方式：
- CHLASPECTRO：光谱法测定的叶绿素a
- CHLAHPLC：液相色谱法测定的叶绿素a
- CHLAFLUO：荧光法测定的叶绿素a
- DVCHLA：二乙烯基叶绿素a
此外，还增设两列以明确测量数据的溯源信息：
- SOURCE：数据来源，取值为SOMLIT或REPHY
- DOI：原始数据集下载页面的数字对象唯一标识符（DOI）