Comparing mineral magnetic properties of sediments in two reservoirs in “strongly” and “mildly” eroded regions on the Guizhou Plateau, southwest China: A tool for inferring differences in sediment sources and soil erosion

Geomorphology ◽  
2011 ◽  
Vol 130 (3-4) ◽  
pp. 255-271 ◽  
Author(s):  
Hongya Wang ◽  
Lin Xu ◽  
Xubo Sun ◽  
Minghui Lu ◽  
Xiaoya Du ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Soil Erosion ◽  
Southwest China ◽  
Sediment Sources ◽  
Mineral Magnetic ◽  
Guizhou Plateau

scholarly journals Tracing the origin of reservoir sediments using magnetic properties in Southeastern Brazil

2020 ◽  
Vol 41 (3) ◽  
pp. 847
Author(s):  
Pedro Luiz Terra Lima ◽  
Marx Leandro Naves Silva ◽  
John Quinton ◽  
Alona Armstrong ◽  
Alberto Vasconcellos Inda ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Soil Erosion ◽  
Control Strategies ◽  
Southeastern Brazil ◽  
Sediment Sources ◽  
Fe Oxide ◽  
Reservoir Sediments ◽  
Tropical Environments ◽  
Negative Impacts ◽  
Tracing Techniques

Determining the origin of eroded soil is essential to design effective soil erosion control strategies which preserve the soil resource, enhance agricultural productivity, and reduce the negative impacts of soil erosion, in-field and off-field. Magnetic properties have been widely used in temperate environments to identify sediment sources, pathways and links, but there have been very few applications in tropical and subtropical environments. Therefore, in this paper we investigated reservoir sediment sources in the Upper Grande River Basin, Southeastern Brazil, using sediment tracing techniques based on magnetic parameters (low and high frequency magnetic susceptibility, frequency dependent susceptibility). The different parent materials and subtropical weathering conditions resulted in soils having different Fe oxide minerals and Fe oxide contents, promoting magnetic variability that allowed comparison and identification of possible sources of reservoir sediments in order to reduce water erosion impacts. The results indicate the suitability of magnetic properties as a tracer for soil erosion studies in tropical environments.

Monitoring of suspended sediment load and Sediment Sources in a Karst Plateau Catchment of Southwest China.

2020 ◽  
Author(s):  
Tao Peng ◽  
Qianyun Cheng ◽  
Le Cao
Keyword(s):  
Soil Erosion ◽  
Suspended Sediment ◽  
Southwest China ◽  
Sediment Load ◽  
River Sediments ◽  
Primary Source ◽  
Suspended Sediments ◽  
Rainfall Erosivity ◽  
Sediment Sources ◽  
Underground River

<p>The development of karst landforms in southwest China has resulted in surface and underground dual hydrogeological structure. The characteristics of the mechanism of soil erosion and its environmental effects are different from those in non-karst regions. This study aims to monitor sediment load and identify the main sediment source in a typical karst plateau agroforestry catchment, to estimate the relative contribution rates of surface and underground river sediment sources. The results show that the annual sediment transport modulus in catchment is very low (5.1 Mg km<sup>-2</sup> a<sup>-1</sup>) in this carbonate agroforestry catchment compare to deforestation 20 years ago (20 Mg km<sup>-2</sup> a<sup>-1</sup>). Sediment Fluxes in the underground river and surface river account for 19.7% and 80.3% respectively. Soil leakage is an important way but not a main way of soil erosion in typical karst watershed. There is no obvious soil erosion on the hillsides (less than 1 Mg km<sup>-2</sup> a<sup>-1</sup>), but the sediment sources results shows sediment sources of surface and underground river are different in 2017 and 2018, In 2017, it indicate that carbonate surface soil contributes 16.2% and 11.9% of the total suspended sediment to the surface and underground river respectively, and the clastic rock pieces are the primary source of both surface and underground river sediments, 79.5% and 60.8% respectively. Subsurface soil contributes a smaller fraction to the total sediment load, 4.3% to surface rivers and 27.3% to underground rivers. The 137Cs values for some suspended sediments in 2018 were outside the range all of the soil source samples, it attributed to re-mobilization of old sediment stored in karst underground conduits during the deforestation, and these “old sediments” could generate to the surface again when with the rainfall erosivity above 49 J·mm·m<sup>-2</sup>·h<sup>-1</sup>.</p>

In situ cosmogenic 10Be, 26Al, and 21Ne dating in sediments from the Guizhou Plateau, southwest China

2021 ◽  
Author(s):  
Ye Yang ◽  
Yu Liu ◽  
Yan Ma ◽  
Sheng Xu ◽  
Cong-Qiang Liu ◽  
...  
Keyword(s):  
Southwest China ◽  
Cosmogenic 10Be ◽  
Guizhou Plateau

A new species ofGyraulus(Gastropoda: Planorbidae) from Ancient Lake Lugu, Yunnan-Guizhou Plateau, Southwest China

2013 ◽  
Vol 33 (1) ◽  
pp. 34-39 ◽  
Author(s):  
Fengyue Shu ◽  
Frank Köhler ◽  
Cuichang Fu ◽  
Hongzhu Wang
Keyword(s):  
New Species ◽  
Southwest China ◽  
Ancient Lake ◽  
Guizhou Plateau ◽  
Lake Lugu ◽  
A New Species

Tracer vertical movement and its affecting factors in karst soil profiles using the simulated leaching method

2021 ◽  
Author(s):  
Jianghu He ◽  
Keli Zhang ◽  
Zihao Cao ◽  
Qihua Ke
Keyword(s):  
Soil Erosion ◽  
Soil Loss ◽  
Southwest China ◽  
Vertical Movement ◽  
Karst Area ◽  
Affecting Factors ◽  
Tracer Movement ◽  
Traditional Research ◽  
Movement Distance ◽  
Karst Geomorphology

<p>Soil erosion is a severe issue in Southwest China due to complex karst geomorphology and excessive farming activities. It is also difficult to observe and evaluate using traditional research methods. Fortunately, as a supplement to traditional methods, the <sup>137</sup>Cs tracing technique has strong potential to monitor and evaluate soil loss in karst regions. However, <sup>137</sup>Cs might move downward with tiny particles under adequate rainfall conditions. This is critical because it directly affects accuracy of using the <sup>137</sup>Cs conversion model to evaluate soil erosion. Thus, in our study, in order to explore whether tracers actually moved vertically and to evaluate the movement distance and the factors influencing the movement, magnetic powder (Fe<sub>3</sub>O<sub>4</sub>) and rare earth oxides (CeO<sub>2 </sub>and La<sub>2</sub>O<sub>3</sub>) were used as the substitute tracers under different conditions (rainfall and leaching area) of a simulated leaching experiment, which possess similar properties as <sup>137</sup>Cs and have no toxicity problems in humans and the environment. The results showed that tracers moved downward 6 cm when water was added to simulate 1-10-year rainfall conditions and 8 cm when water was added to simulate 15-20-year rainfall conditions. The movement distance of tracers increased slowly with increasing water input, and the concentration of the tracers that moved related indirectly to the leaching area. Tracer movement at the edge of the simulated profile was affected by tracer type and concentration since there was no transition layer between soil and plastic column. Our field observations in two karst watersheds showed that ignoring the vertical movement of tracer can cause the overestimation of soil loss amount by 6.90% and 22.22% respectively. This study proved that in the karst area of Southwest China with abundant rainfall, <sup>137</sup>Cs would move vertically, and the soil loss will be overestimated if the vertical movement distance of the tracer is ignored.</p>

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