An Analysis of Land Use Change Dynamics and Its Impacts on Hydrological Processes in the Jialing River Basin

Abstract

Land use changes are important aspects of global change and affect regional water cycles, environmental quality, biodiversity and terrestrial ecosystems. To understand the temporal and spatial land use change in the Jialing River Basin and its impacts on the hydrological cycle, land use change models and the variable infiltration capacity (VIC) model were applied separately to the Jialing River Basin. Real change and final change were analyzed to determine the consequences of land use changes and their hydrological consequences. Real change is defined as the total variation during a fixed period, including increases and decreases. Thus, real change is the sum of the absolute values of the decrease and the increase. Final change is defined as the difference between the beginning and end of a given period for a specific factor. Overall, the amounts of settlement and shrub land area changed significantly in the entire Jialing River (with final change rates of 20.77% and −16.07%, respectively, and real change rates of 34.2% and 30.1%, respectively, from 1985 to 1995, as well as final and real change rates of 29. 37%, 12.40%, 39.9% and 32.8%, respectively, from 1995 to 2000). Compared with the final change, the real change highlighted the rate of change and the change in woodland area. The land use changes in OPEN ACCESSWater 2014, 6 3759 the Lueyang (LY), Shehong (SH) and Fengtan (FT) subcatchments were more dynamic than in the other subcatchments. The economy, population and macro-policy were the main factors responsible for driving the land use changes. The decrease in woodland area in the LY subcatchment corresponded with an increase in evapotranspiration (ET) and with decreases in the other hydrological elements. Overall, the final changes in the hydrological elements in the LY, SH and FT subcatchments were not significant due to the average and compensation effects. The LY subcatchment was mainly affected by the average effect, whereas the SH and FT subcatchments were affected by the average and compensation effects. The use of real change can increase the detectability of hydrological elements changes caused by land use change in SH and FT. The results of this study provide new insights regarding the examination of the effects of land use changes on hydrological regimes. These results are useful for land use planners and water resource managers.

Evolution of the human–water relationships in the Heihe River basin in the past 2000 years

“…However, it is recognized that air temperature is one of most important factors influencing E 0 . As the range of the temperature change over the study period was not more than 2 • in this region (Zheng et al, 2010), and as Zhang et al (2014) found that the E 0 increased by only 1.16 mm per month for a temperature increase of 2 • in the Gulang River basin (next to the Heihe River basin), it was assumed that E 0 in the HRB was constant over the study period and the same as instrumented times. The term w is a catchment-scale model parameter determining the evaporation ratio (E/P ) for a given E 0 /P .…”

Effect of deforestation on watershed water balance: hydrological modelling-based approach / Vplyv odlesnenia na vodnú bilanciu povodia: prístup na báze hydrologického modelovania

“…Anyway, the obvious finding is that the deforestation increases and reforestation decreases the annual flow. At the same time, deforestation increases flood peaks and volumes (Andréssian 2004), while forested catchments have greater infiltration rates, which may decrease catchment runoff (Zhang et al 2014).…”

Study of the Spatiotemporal Characteristics of Meltwater Contribution to the Total Runoff in the Upper Changjiang River Basin

“…On one hand, previous studies showed that vegetation affects snow accumulation by interception and sublimation, and affects snowmelt by alerting the energy balance of land surface [64][65][66]. However, the relationship between snow and vegetation is highly variable and complicated, depending on climatic, topographic and vegetation conditions [65,67,68]; On the other hand, vegetation modifies runoff yield mainly by interception and ET [69,70]. The effects of land cover change on MCR cannot be evaluated since we adopted the constant land cover during the entire study period.…”