石臼湖正构烷烃及单体碳同位素记录数据集（1862-2010年）

正构烷烃及单体碳同位素的分布特征揭示了不同时期人类活动对湖区生态环境的影响：1862～1970年，总有机碳(TOC)、总氮(TN)及中低奇数碳正构烷烃(C17～C25)相对含量较低，长链正构烷烃单体碳同位素(δ13C25～31)值偏轻，说明人类活动对湖区环境影响较小，生态环境相对稳定；1970～1983年，TOC、TN及C17～C25相对含量显著增加，δ13C25～31值明显偏重，指示此时期内围湖造田、化肥农药滥用及废水排放等人类活动造成湖区陆生高等植物退化，水体中藻类暴发，湖泊富营养化程度显著提高，生态环境急剧恶化；1983～2010年，TOC、TN及C17～C25相对含量仍处于高值范畴，湖泊富营养化问题没有得到有效控制，湖区生态环境整体呈现相对退化趋势。The distribution characteristics of n-alkanes and their compound-specific carbon isotopes reveal the impacts of human activities on the lacustrine ecological environment across different time periods: From 1862 to 1970, the relative contents of total organic carbon (TOC), total nitrogen (TN), and low-to-middle chain odd-numbered n-alkanes (C17–C25) were relatively low, while the compound-specific carbon isotope values of long-chain n-alkanes (δ13C25–31) were depleted, indicating that human activities had little impact on the lacustrine environment and the ecological environment was relatively stable; From 1970 to 1983, the relative contents of TOC, TN and C17–C25 increased significantly, and the δ13C25–31 values became obviously enriched, indicating that human activities such as lake reclamation, overuse of chemical fertilizers and pesticides, and wastewater discharge during this period led to the degradation of terrestrial higher plants in the lake area, the outbreak of algae in the water body, a significant increase in lake eutrophication degree, and a sharp deterioration of the ecological environment; From 1983 to 2010, the relative contents of TOC, TN and C17–C25 remained at high levels, the lake eutrophication problem was not effectively controlled, and the overall lacustrine ecological environment showed a relatively degraded trend.