Potential Toxic Elements (PTEs) Dataset of Surface Sediments in the Sanjiangyuan Region

1. Dataset Title
Potential Toxic Elements (PTEs) Dataset of Surface Sediments in the Sanjiangyuan Region
2. Authors & Affiliation
Dongdong Chen, Qi Li, Yukun Zhang, Li Zhang, Fuquan He, Quanbang Li, Liang Zhao (Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China)
Xin Chen (Xingzhi College, Zhejiang Normal University, Jinhua 321000, China)
Zongjian Zhao (Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China)
3. Contact Information
Corresponding Author: Liang Zhao
E-mail: [e-mail]
Affiliation: Northwest Institute of Plateau Biology, Chinese Academy of Sciences
Address: Xining 810008, Qinghai Province, China
4. Geographic Coverage
4.1 Study Area
Sanjiangyuan Region, located in the hinterland of the Qinghai-Tibet Plateau (31°39′-36°16′ N, 89°24′-102°23′ E), southern Qinghai Province, China. As the source area of the Yellow River, Yangtze River, and Lancang River (Mekong River), it is known as "China's Water Tower". It plays a critical role in the national ecological security barrier.
4.2 Sampling Site Distribution
Sampling sites cover the main streams and tributaries of three major river systems, with a total of 48 sampling points (Figure 1 in the associated manuscript):
5. Data Content and Structure
The dataset is stored as an Excel file with 4 worksheets, integrating raw concentration data, pollution assessment indices, and source apportionment results. All data are complete (no missing values) and consistent with the analytical results in the associated manuscript.
6. Data Collection and Processing Methods
6.1 Sample Collection
Medium: Surface sediments collected via the multi-point mixing method.
Preservation: Samples sealed in acid-washed polyethylene bags, stored at 4°C, air-dried, and sieved through a 0.15 mm mesh in the laboratory.
6.2 Laboratory Analysis
Instrumentation: Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for Cr, Ni, Cu, Zn; atomic fluorescence spectrometry for Hg, As, Pb, Cd (compliant with Chinese national standards GB/T 17141—1997, GB/T 22105.1-2008, GB/T 22105.2—2008).
Quality Control: Method Detection Limits (MDLs): Hg=0.002 mg kg-1, As=0.01 mg kg-1, Pb=17.50 mg kg-1, Cr=7.500 mg kg-1, Cd=0.050 mg kg-1, Ni=1.750 mg kg-1, Cu=1.500 mg kg-1g, Zn=1.000 mg kg-1; recovery rate: 85%–115%.
6.3 Data Calculation
Enrichment Factor (EF): Normalized by Ni (reference element) with background values from Chinese fluvial sediments.
Geo-accumulation Index (Igeo): Igeo = log₂(Cₙ/(1.5×Bₙ)), where Cₙ=measured concentration, Bₙ=background value.
PMF Model: EPA-PMF 5.0 with 5 factors (Qrobust/Qtrue=60.3, residuals within [-3, 3]).
7. Data Format
File Type: Microsoft Excel (.xlsx)
Compression: Uncompressed (single file)
Encoding: UTF-8

8. Acknowledgment
This work was supported by the Chief Scientist Program of Qinghai Province (2024-SF-102).

1. 数据集标题
三江源地区表层沉积物潜在有毒元素（Potential Toxic Elements，PTEs）数据集
2. 作者及所属机构
陈东冬、李琦、张玉坤、张莉、何福全、李全邦、赵亮（中国科学院西北高原生物研究所，西宁 810008，中国）
陈鑫（浙江师范大学行知学院，金华 321000，中国）
赵宗健（中国科学院西北高原生物研究所，西宁 810008，中国；中国科学院大学，北京 100049，中国）
3. 联系方式
通讯作者：赵亮
电子邮箱：[e-mail]
所属机构：中国科学院西北高原生物研究所
通讯地址：中国青海省西宁市 810008
4. 地理覆盖范围
4.1 研究区域
三江源地区位于青藏高原腹地（北纬31°39′—36°16′，东经89°24′—102°23′），地处中国青海省南部。作为黄河、长江、澜沧江（湄公河）的源头区域，该地区被誉为“中华水塔”，在国家生态安全屏障中发挥着至关重要的作用。
4.2 采样点分布
采样点覆盖三大河流水系的干流与支流，共计48个采样点（详见相关学术论文中的图1）：
5. 数据内容与结构
本数据集以Microsoft Excel格式存储，包含4个工作表，整合了原始浓度数据、污染评价指数及源解析结果。所有数据完整无缺失值，且与相关学术论文中的分析结果一致。
6. 数据采集与处理方法
6.1 样品采集
介质：采用多点混合法采集表层沉积物。
保存：样品密封于酸洗聚乙烯袋中，4℃冷藏，经实验室风干后过0.15mm筛。
6.2 实验室分析
仪器：采用电感耦合等离子体原子发射光谱法（Inductively Coupled Plasma Atomic Emission Spectrometry，ICP-AES）测定Cr、Ni、Cu、Zn含量；采用原子荧光光谱法测定Hg、As、Pb、Cd含量，分析方法符合中国国家标准GB/T 17141—1997、GB/T 22105.1-2008及GB/T 22105.2—2008。
质量控制：方法检出限（Method Detection Limits，MDLs）：Hg=0.002 mg·kg⁻¹，As=0.01 mg·kg⁻¹，Pb=17.50 mg·kg⁻¹，Cr=7.500 mg·kg⁻¹，Cd=0.050 mg·kg⁻¹，Ni=1.750 mg·kg⁻¹，Cu=1.500 mg·kg⁻¹，Zn=1.000 mg·kg⁻¹；回收率范围为85%—115%。
6.3 数据计算方法
富集因子（Enrichment Factor，EF）：以Ni作为参比元素，采用中国河流沉积物背景值进行归一化处理。
地质累积指数（Geo-accumulation Index，Igeo）：计算公式为Igeo = log₂(Cₙ/(1.5×Bₙ))，其中Cₙ为实测浓度，Bₙ为背景值。
正定矩阵因子分解模型（PMF Model）：采用EPA-PMF 5.0版本，设置5个因子，Qrobust/Qtrue=60.3，残差范围为[-3, 3]。
7. 数据格式
文件类型：Microsoft Excel (.xlsx)
压缩方式：未压缩（单文件）
编码格式：UTF-8
8. 致谢
本研究得到青海省首席科学家项目（2024-SF-102）资助。