Chironomid counts and loss-on-ignition for a 28cm long gravity core from lake Støylsvatnet, Norway

This dataset provides chironomid count data and loss-on-ignition measurements for a short sediment record from lake Støylsvatnet, located in the Førde region, Norway. The core spans 28 cm and dates from ca 940 CE to the present. We obtained a sediment core from the centre of the lake (8.3 m water depth) using a HON/Kajak gravity corer during fieldwork in September 2019, and subdivided the core into 1-cm-thick samples in the field. Samples were transported to the laboratory (Birkbeck University of London, UK), where they were weighted and processed using standard protocols – this involved 20 min treatment with warm KOH (10 %) and sieving over a 100 µm mesh. Chironomid head capsules were subsequently handpicked from the residue, mounted on permanent microscope slides, and identified using Brooks et al. (2007). This dataset provides chironomid count data in number of chironomid head capsules per sample. Additionally, loss-on-ignition was determined for each sample by comparing the dry weight of the sample before and after combustion at 550°C following Heiri et al. (2001). The chironomid dataset provides insight in centennial-scale changes in the insect community of the lake ecosystem under past climate change and current anthropogenic impact.

本数据集提供了挪威菲尤尔（Førde）地区斯托伊尔湖（Støylsvatnet）一处短沉积序列的摇蚊（Chironomid）计数数据与烧失量（loss-on-ignition）测定结果。该沉积岩芯总长28厘米，年代跨度约为公元940年至今。2019年9月的野外考察中，研究团队采用HON/Kajak重力采样器，从该湖湖心（水深8.3米）采集了沉积岩芯，并于野外将岩芯切割为1厘米厚度的样品。样品被运送至英国伦敦大学伯贝克学院（Birkbeck University of London）实验室，按照标准操作规程进行称重与前处理：包括用10%温热氢氧化钾（KOH）溶液浸泡处理20分钟，随后过100微米（µm）筛网。之后研究人员从筛上残留物中手动挑取摇蚊头囊，将其封固于永久显微载玻片上，并参照Brooks等（2007）的方法进行物种鉴定。本数据集以每样品的摇蚊头囊数量为单位，提供摇蚊计数数据。此外，参照Heiri等（2001）的方法，通过测量样品在550℃灼烧前后的干重差值，计算得到每个样品的烧失量。本摇蚊数据集可为揭示过去气候变化与当前人为扰动背景下湖泊生态系统昆虫群落的百年尺度变化提供科学依据。