Responses of streamflow to changes in climate and land use/cover in the Loess Plateau, China

Abstract

[1] To control the severe soil erosion in the Loess Plateau, China, a great number of soil conservation measures including terracing, afforestation, and construction of sedimenttrapping dams have been implemented since the 1950s. These measures have resulted in large-scale land use and land cover change. It is important to evaluate the impacts of these soil conservation measures on streamflow as streamflow is an important determinant on catchment sediment yield and obviously is related to water security in the region. In this study, data from 11 catchments in the Loess Plateau were analyzed to investigate the responses of streamflow to the land use/cover changes. The nonparametric MannKendall test and the Pettitt test were used to identify trends and change points in the streamflow records. All 11 catchments had significant negative trend in annual streamflow of À0.13 to À1.58 mm a À1 . Change points in streamflow occurred between 1971 and 1985. A method was employed to evaluate the impacts of climate variability and land use/ cover changes on mean annual streamflow on the basis of precipitation and potential evaporation. It was estimated that the land use/cover changes accounted for over 50% of the reduction in mean annual streamflow in 8 out of the 11 catchments. However, climate (i.e., precipitation and potential evaporation) played a more important role in reducing the streamflow in the three remaining catchments. Among the soil conservation measures, construction of sediment-trapping dams and reservoirs, with associated irrigation water extractions from the latter, appeared to be the main cause of the reduced streamflow.Citation: Zhang, X., L. Zhang, J. Zhao, P. Rustomji, and P. Hairsine (2008), Responses of streamflow to changes in climate and land use/cover in the Loess Plateau, China, Water Resour. Res., 44, W00A07,

Determining the hydrological responses to climate variability and land use/cover change in the Loess Plateau with the Budyko framework

“…The Loess Plateau of China is well known for the severe soil erosion and heavy sediment load because of the low vegetation cover, frequent high-rainfall storms in summer months, highly erodible loessial soil, steep topography, and long history of intensive cultivation and unsustainable land uses (Zhang et al, 2008). To control the severe soil erosion in the Loess Plateau, several soil and water conservation measures including afforestation, pasture reestablishment, terraces and checkdams have been implemented since the 1950s Zhang et al, 2008).…”

“…To control the severe soil erosion in the Loess Plateau, several soil and water conservation measures including afforestation, pasture reestablishment, terraces and checkdams have been implemented since the 1950s Zhang et al, 2008). A large reforestation campaign, the Grain-forGreen (GFG) project, which involved returning steep croplands to forest and pasture lands, was implemented at the end of the 1990s .…”

“…The streamflow within the Loess Plateau has exhibited an obvious downward trend over the past six decades (Zhang et al, 2008;Zhao et al, 2014;Gao et al, 2015;Zhang et al, 2016). Many studies have investigated the effects of land use/cover change and climate variability on streamflow in the Loess Plateau to support future water resource and local ecosystem management efforts.…”

“…Many studies have investigated the effects of land use/cover change and climate variability on streamflow in the Loess Plateau to support future water resource and local ecosystem management efforts. Zhang et al (2008) used the climate elasticity approach to explore the reasons for streamflow reduction in 11 catchments of the Loess Plateau between the 1950s and 2000, and found that land use/cover changes accounted for more than 50% of the reduction in 8 of the 11 catchments, while climate played a more important role in the three remaining catchments. Using the Budyko's curve equation and linear regression analysis, Zhao et al (2014) indicated that human activities accounted for the majority of the streamflow changes in most of the tributaries in the middle reaches of the Yellow River basin between the 1950s and 2010.…”

Vegetation changes in recent large-scale ecological restoration projects and subsequent impact on water resources in China's Loess Plateau

“…However, due to adverse environmental conditions (e.g., sparse vegetation coverage, periodic high intensity rainstorms) and intensified human activities (e.g., over grazing and coal mining) (Liang et al, 2013;Zhang et al, 2008), this region suffers from severe soil erosion and the average annual soil erosion rate of 2000-2008 is 3180 t km −2 yr −1 under soil erosion control service (Fu et al, 2011). The Northern Shaanxi Loess Plateau (NSLP), located in the middle of the Loess Plateau, is characterized by typical loess hills and gullies.…”