3.2 Hydrological modeling using GBHM
The GBHM is a distributed hydrological model that was proposed in 1998
by Yang et al. (1998). In this model, the basin can be divided into
several mountain slope units, and the regional runoff generation and
concentration processes are expressed based on the ”slope-river course”
using physical equations (Lyu et al., 2019; Ma et al., 2010). The model
can be described according to the following components: input, spatial
database, calculation of hydrological processes, and output (Yang et
al., 2002). Model input data include basic geographic information data
(e.g., DEM, river network), daily meteorological data (e.g.,
precipitation, temperature), annual land use data, and annual NDVI data.
To adequately characterize the hydrological response of the Qinhe River
Basin to the construction of reservoirs, the principal parameters of the
model were adjusted for the present study. The impacts of underlying
changes at the surface and major soil and water conservation measures on
temporal and spatial changes in runoff for the basin were also examined.
A schematic illustration of the improved model is displayed in Figure 3.