Abstract
Human activities affecting hydrological processes in a catchment have
many forms and the effect of those activities on the propagation of
drought in a catchment depends on the relevant scales of the processes
involved. The research presented focuses on the influence of reservoir
and land use on drought dynamics. As a case study, we use the River
Kamienna, Swietokrzyskie mountains, Poland. The Kamienna River has a
mountainous character, with several water retention reservoirs and a
history of industrial activities in the region. Annual water balance is
also affected by water withdrawals in the catchment. Modeling tools in
the form of lumped and semi-distributed hydrological models are applied
to analyze hydrological processes in the catchment and to separate
climatological and human-related factors affecting them. Two main goals
of the modeling can be summarized as an investigation of the effects of
reservoir operation on hydrological processes, especially dry season
runoff, and an analysis of impacts of land-use change on the
spatial-temporal characteristics of hydrological drought propagation. We
apply three different models to simulate the catchment hydrological
processes: two semi-distributed models, SWAT, and TOPMODEL, and the
lumped hydrological model HBV. We present the calibration and
verification of the models applied and a comparison of results using the
goodness of fit criteria. The simulated flow at the gauging station
along the Kamienna River is compared with the observed flow. The study
applies several flow-related indices to understand how the climate and
human-induced changes are affecting flow patterns in the region. The
flow regime is described using a baseflow index and the runoff
coefficient. The standardized runoff index (SRI) and runoff coefficients
are also derived for the catchment. The results indicate that human
activities dominated the decrease in runoff over the Kamienna River. The
main finding shows that man-made activities such as the construction of
reservoirs, land-use changes, mining, etc. have led to a more severe
hydrological drought than under natural conditions. The research is part
of the project “Human and climate impacts on drought dynamics and
vulnerability” HUMDROUGHT (http://HUMDROUGHT.igf.edu.pl).