SOMLIT-Sète time series (French Research Infrastructure ILICO): long-term core parameter monitoring of the water column in the continental shelf in front of Sète City, North-western Mediterranean Sea

The SOMLIT-Sète station is a part of the French monitoring network SOMLIT (Service d’Observation en Milieu Littoral, https://www.somlit.fr/), accredited by the French Centre National de la Recherche Scientifique (CNRS) as a National Observatory System (SNO). The main scientific objective of the observations at the SOMLIT-Sète station is to assess the long-term impact of climate change and human activities on the coastal Northwestern Mediterranean ecosystem, the impact of potential mid- and long-term changes in continental inputs, as well as changes in the productivity of the Gulf of Lion coastal zone. The SOMLIT-Sète station (latitude 43.3267N, longitude 3.66167E) is located in the dilution zone of a large river, the Rhône, but also small coastal rivers (Vène, Aude, Herault), especially those of the Thau lagoon basin. The SOMLIT-Sète Station is monitored from the Station Méditerranéenne de l’Environnement Littoral (SMEL) of the University of Montpellier in Sète by the staff of the OSU OREME, and the Research Unities of MARBEC (http://www.umr-marbec.fr/en/) and GéoSciences (http://www.gm.univ-montp2.fr/?lang=en). The SOMLIT-Sète station, located on a water-column depth of 30 m, is sampled at the water surface in a bi-monthly frequency. The SOMLIT-Sète station is implemented near an instrumented Cardinal Buoy integrating on the same site two other monitoring systems called SNO COAST-HF (Coastal ocean observing system - High Frequency), and SNO PHYTOBS (Phytoplankton observation network), entitling at site: COAST HF-Sète and PHYTOBS-Sète. The SOMLIT-Sète is part of the long-term coastal observation stations of the French Research Infrastructure dedicated to coastal ocean observations (Infrastructure de Recherche Littorale et Côtières: ILICO, https://www.ir-ilico.fr). Bi-monthly collected samples are analyzed for more than 20 core parameters such as temperature, salinity, dissolved oxygen, pH, ammonia, nitrates, nitrites, phosphates, silicates, suspended matter, particulate organic carbon, particulate organic nitrogen, chlorophyll-a, delta15N, delta13C; pico- and nano- plankton; and CTD-PAR-Chla fluorescence profile. The SOMLIT network quality management system is in line with the ISO/IEC 17025:2017 standard: “General requirements for the competence of testing and calibration laboratories”. Further information on standard operating procedures for sample collection and data acquisition are available at: https://www.somlit.fr/parametres-et-protocoles. For more information on the quality flagging scheme: https://www.somlit.fr/codes-qualite/.SOMLIT-Sète站是法国沿海观测网络SOMLIT（沿海环境观测服务，Service d’Observation en Milieu Littoral，https://www.somlit.fr）的组成部分，该网络获法国国家科学研究中心（Centre National de la Recherche Scientifique，CNRS）认证为国家观测系统（National Observatory System，SNO）。SOMLIT-Sète站观测的核心科学目标为评估气候变化与人类活动对西北地中海沿岸生态系统的长期影响、大陆输入物中长期潜在变化的影响，以及利翁湾沿岸海域生产力的变化情况。该站点（纬度43.3267°N，经度3.66167°E）地处大型河流罗讷河与多条小型沿海河流（韦讷河、奥德河、埃罗河）的稀释混合区，尤以泰奥泻湖流域的河流为主。SOMLIT-Sète站由蒙彼利埃大学地中海沿海环境站（Station Méditerranéenne de l’Environnement Littoral，SMEL）的OSU OREME团队、MARBEC研究单元（http://www.umr-marbec.fr/en/）与GéoSciences研究单元（http://www.gm.univ-montp2.fr/?lang=en）负责运维监测。该站点所处水深为30米，采用双月频次对表层水体开展采样。SOMLIT-Sète站邻近一台集成了另外两套监测系统的仪器化主方位浮标（Cardinal Buoy），这两套系统分别为SNO COAST-HF（沿海海洋观测系统-高频）与SNO PHYTOBS（浮游植物观测网络），对应站点标识为COAST HF-Sète与PHYTOBS-Sète。SOMLIT-Sète站同时隶属于法国沿海海洋观测专属研究基础设施——沿海与海岸研究基础设施（Infrastructure de Recherche Littorale et Côtières，ILICO，https://www.ir-ilico.fr）的长期沿海观测站体系。每双月采集的样本将针对20余项核心参数开展分析，包括温度、盐度、溶解氧、pH、氨氮、硝酸盐、亚硝酸盐、磷酸盐、硅酸盐、悬浮颗粒物、颗粒有机碳、颗粒有机氮、叶绿素a、δ15N、δ13C、微微型与纳米级浮游生物，以及CTD-PAR-Chla荧光剖面。SOMLIT网络的质量管理体系符合ISO/IEC 17025:2017标准《检测和校准实验室能力的通用要求》。有关样品采集与数据获取的标准操作规程的详细信息，可访问https://www.somlit.fr/parametres-et-protocoles；关于质量标记方案的更多说明，可查阅https://www.somlit.fr/codes-qualite/。