Late Holocene vegetation dynamic and human activities reconstructed from lake records in western Loess Plateau, China

Quantifying the relative contributions of climate variability and human activity to streamflow change is important for effective water resource use and management. Four sub-catchments of the Wei River Basin (WRB) in the Loess Plateau in China were selected as the study region, where the evolution of parameter α from the latest Budyko equation (Wang-Tang equation) was explored using an 11-year moving window. The elasticity of streamflow was derived from the climatic aridity index, represented by the ratio of annual potential evaporation ( E P ) to annual precipitation ( P ), and catchment characteristics as represented by α . The effects of climate change and human activities on streamflow change during 1971–2010 were quantified with climate elasticity and decomposition methods. The contributions of different types of human activities to streamflow were further empirically determined using the water and soil conservation method. Results indicate that (1) under the same climate condition ( P and E P ), a higher value of α caused an increase in evaporation rate ( E / P ) and a decrease in runoff. Changes in these hydrological variables led to a subsequent reduction in streamflow in the WRB; (2) The absolute value of the precipitation elasticity was larger than the potential evaporation elasticity, indicating that streamflow change was more sensitive to precipitation; (3) The results based on the two methods were consistent. Climate change and human activities contributed to the decrease in streamflow by 29% and 71%, respectively, suggesting that human activities have exerted more profound impacts on streamflow in the study region; (4) Contributions of different water and soil conservation measures to streamflow reduction were calculated and sorted in descending order: Irrigation, industrial and domestic consumption, terrace, afforestation, reservoirs, check-dams, then grass-planting.

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Plant diversity of the Tianshui Basin in the western Loess Plateau during the mid-Holocene – Charcoal records from archaeological sites

Quaternary International ◽

10.1016/j.quaint.2013.05.014 ◽

2013 ◽

Vol 308-309 ◽

pp. 27-35 ◽

Cited By ~ 10

Author(s):

Nan Sun ◽

Xiaoqiang Li ◽

John Dodson ◽

Xinying Zhou ◽

Keliang Zhao ◽

...

Keyword(s):

Loess Plateau ◽

Plant Diversity ◽

Archaeological Sites ◽

Tianshui Basin ◽

Western Loess Plateau

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Changes in streamflow regimes and their response to different soil and water conservation measures in Loess Plateau watersheds

10.22541/au.161734646.68347691/v1 ◽

2021 ◽

Author(s):

Shuyu Zhang ◽

Guangju Zhao ◽

Xingmin Mu ◽

Peng Tian

Keyword(s):

Loess Plateau ◽

Water Conservation ◽

Human Activities ◽

Soil And Water Conservation ◽

Low Flow ◽

Hydrological Change ◽

River Watershed ◽

Daily Streamflow ◽

Conservation Measures ◽

Soil And Water

Investigating the changes in streamflow regimes is useful for understanding the mechanisms associated with hydrological processes in different watersheds and for providing information to facilitate water resources management. In this study, we selected three watersheds, i.e., Sandu River, Hulu River, and Dali River on the Loess Plateau, to examine the changes in the streamflow regimes and to determine their responses to different soil and water conservation measures (terracing, afforestation, and damming). The daily runoff was collected continuously by three hydrological gauges close to the outlets of the three watersheds from 1965 to 2016. The eco-surplus, eco-deficit, and degree of hydrological change were assessed to detect hydrological alterations. The Budyko water balance equation was applied to estimate the potential impacts of climate change and human activities on the hydrological regime changes. Significant decreasing trends (P < 0.05) were detected in the annual streamflow in the Sandu and Dali River watersheds, but not in the Hulu River watershed where afforestation dominated. The annual eco-surplus levels were low and they decreased slightly at three stations, whereas the eco-deficit exhibited dramatic increasing trends in the Sandu and Dali River watersheds. In the Sandu River watershed (dominated by terraces), the runoff exhibited the most significant reduction and the eco-deficit was the highest among the three watersheds. The integral degrees of hydrological change were higher in the Sandu River watershed than the other two watersheds, thereby suggesting substantial variations in the magnitude, duration, frequency, timing, and rate of change in the daily streamflow. In the Dali River watershed (dominated by damming), the changes in the extreme flow were characterized by a decreasing number appearing in high flow. In these watersheds, human activities accounted for 74.1% and 91.78% of the runoff reductions, respectively. In the Hulu River watershed (dominated by afforestation), the annual runoff exhibited an insignificant decreasing trend but with a significant increase in the low flow duration. Rainfall changes accounted for 64.30% of the runoff reduction.

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Is there a regularity: the change of arable land use pattern under the influence of human activities in the Loess Plateau of China?

Environment Development and Sustainability ◽

10.1007/s10668-020-00909-5 ◽

2020 ◽

Author(s):

Jun Zhang ◽

Junping Yan ◽

Liang Xue ◽

Yuanzhi Yao ◽

Xin Shu

Keyword(s):

Land Use ◽

Loess Plateau ◽

Human Activities ◽

Arable Land ◽

The Loess Plateau ◽

Land Use Pattern ◽

Use Pattern ◽

Arable Land Use

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Effects of Stubble Management on Soil Fertility and Crop Yield of Rainfed Area in Western Loess Plateau, China

Applied and Environmental Soil Science ◽

10.1155/2012/256312 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

G. B. Huang ◽

Z. Z. Luo ◽

L. L. Li ◽

R. Z. Zhang ◽

G. D. Li ◽

...

Keyword(s):

Soil Erosion ◽

Soil Fertility ◽

Loess Plateau ◽

Soil N ◽

The Loess Plateau ◽

Stubble Retention ◽

Severe Erosion ◽

Agriculture Sustainability ◽

Sloping Land ◽

Western Loess Plateau

The combination of continuous cereal cropping, tillage and stubble removal reduces soil fertility and increases soil erosion on sloping land. The objective of the present study was to assessment soil fertility changes under stubble removal and stubble retention in the Loess Plateau where soil is prone to severe erosion. It was indicated that soil N increased a lot for and two stubble retention treatments had the higher N balance at the end of two rotations. Soil K balance performed that soil K was in deficient for all treatments and two stubble retention treatments had lower deficit K. The treatments with stubble retention produced higher grain yields than the stubble removal treatments. It was concluded that stubble retention should be conducted to increase crops productivity, improve soil fertility as well as agriculture sustainability in the Loess plateau, China.

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Effects of climatic variability and human activity on runoff in the Loess Plateau of China

The Forestry Chronicle ◽

10.5558/tfc2013-032 ◽

2013 ◽

Vol 89 (02) ◽

pp. 153-161 ◽

Cited By ~ 2

Author(s):

Yang Zhao ◽

Xinxiao Yu

Keyword(s):

Soil Water ◽

Loess Plateau ◽

Water Conservation ◽

Human Activities ◽

Climatic Variability ◽

Land Use Changes ◽

Annual Runoff ◽

Central China ◽

Vegetative Cover ◽

The Loess Plateau

The Loess Plateau in north-central China has a long history of human activities. As a result of climate change, deforestation and sparse vegetative cover, the region suffers from water shortages and severe soil erosion, significantly influencing efforts for sustainable social development. In order to understand the impacts of climatic variability and human activities on runoff and other hydrological factors in this region, the Luoyugou catchment and its paired catchments (Qiaozidong and Qiaozixi) were selected. Statistical analysis indicated precipitation did not vary significantly whereas the annual runoff decreased from 1986 to 2008, with an abrupt change in 1994. Actual evapotranspiration (AET) increased slightly but not significantly. A comparison of runoff in the paired catchments showed land use changes reduced runoff by more than 38% under the same rainfall conditions. Human activities were the strongest contributor to changes in runoff and AET, at 67% and 90% respectively, while the remaining contributor was climate variation. The influence of various human activities on runoff is quite different, and soil-water conservation initiatives have a greater impact on runoff (about 41%). Thus, human activities were the primary reason for the reduction in runoff in the study catchment compared to climate. Greater emphasis should be given to afforestation and soil-water conservation measures.

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