Catchment recession analysis for environmental impacts on
storage-discharge dynamics
- Chia-Chi Huang,
- Hsin-Fu Yeh
Abstract
The complex interaction of climate change and human activities has led
to significant changes in hydrological patterns, thus affecting the
catchment hydrological processes around the world. This has resulted in
increased water resource problems and conflicts between social
development and environmental sustainability. Moreover, the groundwater
resource is less concerned than others due to the challenges posed by
groundwater and aquifer monitoring. Recession analysis is typically used
to explore the groundwater-streamflow relationship with easily
accessible streamflow data. The environmental impacts can be considered
as a variable into the recession analysis to assess the changes in
dynamic groundwater storage and storage-discharge relationships.
Seventeen gauge stations in Southern Taiwan were selected as a case
study to elucidate the spatial and temporal results under a
comprehensive impact. In addition, the quantified environmental impacts
and changes in vegetation coverage were compared to assess whether these
changes were consistent and their effect on the catchment drainage
processes. The results showed that the regional differences in low-flow
recession characteristics and the dynamic storage indicated the local
differences in the aquifer properties. Decreasing dynamic storage and
increasing storage-discharge sensitivities in most catchments indicated
a consistent change with quantified environmental impacts. This
demonstrated that the environmental change led to more groundwater loss
and a lower streamflow with a reduced flow variation. This study
attempted to explore the storage-discharge dynamics caused by the
overall environmental impact, and the quantified impact can help us to
realize whether the groundwater storage and the susceptibility to
baseflow increase or decrease in the catchment drainage behaviors. This
provides a simple way to explain comprehensive effect on
storage-discharge processes under the environmental co-evolution.