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Baseflow dynamics and multivariate analysis using bivariate and multiple wavelet coherence in an alpine endorheic
Qingping Cheng1, Fanglei Zhong2, Ping Wang3
1School of Geography and Ecotourism, Southwest Forestry University, Kunming, Yunnan 650224, China; Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
The Science of the Total Environment
|March 27, 2021
Summary
Baseflow in the Heihe River Basin originates mainly from groundwater. Climate change impacts upstream baseflow, while both climate and human activities affect downstream flow.
Area of Science:
- Hydrology
- Environmental Science
- Climate Science
Background:
- Baseflow is a critical streamflow component influenced by multiple factors.
- Accurate baseflow estimation is vital for understanding river basin dynamics.
Purpose of the Study:
- To estimate baseflow in the Heihe River Basin (HRB) using digital filtering.
- To identify relationships between baseflow and meteorological/circulation factors using wavelet coherence.
Main Methods:
- Digital filtering for baseflow separation.
- Bivariate and multivariate wavelet coherence for factor analysis.
- Spearman correlation for assessing relationships.
Main Results:
- Average baseflow index (BFI) was 0.62, indicating significant groundwater contribution.
- Precipitation and Atlantic Multidecadal Oscillation were key individual factors.
- Climate change impacts upstream baseflow; human activities influence midstream/downstream baseflow.
Conclusions:
- Hydrometeorological models for HRB should prioritize climate change in the upstream.
- Midstream and downstream models must incorporate both climate change and human impacts.
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