Comprehensive network hydraulic scaling datasets and associated resources (discharge, channel length surveys, watershed metadata, blueline network shapefiles and reference images)

Wetted channel networks expand and contract throughout the year. Direct observation of this process can be made by multiple intensive surveys of a catchment throughout the year. Godsey et al. (2014) suggest that the extent of the wetted channel network scales with discharge at the outlet by a power law (L = αQ^β). Using this relationship, we developed a framework to assess variability in the extent of wetted channels as a function of β and the variability in streamflow Q (Lapides et al., In Review, https://eartharxiv.org/mc6np/). This resource constitutes the empirical basis for that study, a comprehensive dataset compiled from literature including:

1 - Channel length survey data (csv files)
2 - Discharge time series data (csv files)
3 - Watershed metadata (csv file)
4 - Blueline network files (pdf, png, and shp files)

This collection is comprehensive in that it includes all watersheds where at least three channel length surveys have been conducted and where a corresponding discharge time series dataset is available. The requirement of a minimum of three channel length surveys stems from the data requirements to find α and β for the power law relationship between discharge and stream network length for headwater catchments (Godsey et al., 2014). At present, data for 14 watersheds worldwide are included in the collection along with reference maps, watershed metadata, shapefiles and a composite of USGS blueline stream network imagery with terrain for watersheds of interest in the United States. Notably, this collection brings data from a variety of earth science agencies worldwide into a common, clearly labelled format.

Methods used to process the datasets or create other assets in this collection are included in the abstracts or additional metadata for each of the four resources listed above. Python code used to process data, compute variables, and create graphics is available at: https://zenodo.org/record/4057320

湿态河道网络（Wetted Channel Network）会在全年中不断扩张与收缩。对该过程的直接观测，可通过对某一流域（Catchment）开展全年多轮密集踏勘完成。Godsey等人（2014年）提出，湿态河道网络的覆盖范围与流域出口处的流量（Discharge）呈幂律（Power Law）关系：$L = alpha Q^eta$。基于该关系，我们构建了一套框架，用于基于$eta$参数与径流$Q$的变异性，评估湿态河道覆盖范围的变化情况（Lapides等人，已投稿待刊，https://eartharxiv.org/mc6np/）。本数据集为该项研究提供了实证基础，是从公开文献中整合得到的综合数据集，具体包含以下内容：
1. 河道长度踏勘数据（CSV格式文件）
2. 流量时间序列数据（CSV格式文件）
3. 流域元数据（CSV格式文件）
4. 蓝线河道网络文件（包含PDF、PNG及SHP格式文件）

本数据集具有全面性：其收录的所有流域，均至少开展过3次河道长度踏勘，且配有对应的流量时间序列数据集。设置“至少3次河道长度踏勘”这一要求，是为了满足源头流域（Headwater Catchment）流量与河道网络长度之间幂律关系的$alpha$、$eta$参数拟合的数据需求（Godsey等人，2014年）。目前，本数据集已收录全球范围内14个流域的相关数据，其中包括美国境内目标流域的参考地图、流域元数据、形状文件（SHP格式），以及美国地质调查局（USGS）发布的蓝线河道网络影像与地形的合成图。值得注意的是，本数据集将全球多家地球科学机构的相关数据整合为统一且标注清晰的格式。

本数据集的处理方法及其他配套素材的制作方法，已在上述四类资源的摘要或附加元数据中予以说明。用于数据处理、变量计算及绘图的Python代码已公开于：https://zenodo.org/record/4057320