Assessing Soil Erosion Rates on Manually-Tilled Hillslopes in the Sichuan Hilly Basin Using 137Cs and 210Pbex Measurements

doi:10.1016/S1002-0160(07)60034-4

Pedosphere

Volume 17, Issue 3, June 2007, Pages 273-283

https://doi.org/10.1016/S1002-0160(07)60034-4 Get rights and content

Abstract

Purple soils are widely distributed in the Sichuan Hilly Basin and are highly susceptible to erosion, especially on the cultivated slopes. Quantitative assessment of the erosion rates is, however, difficult due to small size of the plots of the manually-tilled land, the complex land use, and steep hillslopes. ¹³⁷Cs and ²¹⁰Pbex (excess ²¹⁰Pb) tracing techniques were used to investigate the spatial pattern of soil erosion rates associated with slope-land under hoe tillage in Neijiang of the Sichuan Hilly Basin. The ¹³⁷Cs and ²¹⁰Pbex inventories at the top of the cultivated slope were extremely low, and the highest inventories were found at the bottom of the cultivated slope. By combining the erosion rates estimates provided by both ¹³⁷Cs and ²¹⁰Pb_ex measurements, the weighted mean net soil loss from the study slope was estimated to be 3100 t km⁻² year⁻¹, which was significantly less than 6930 t km⁻² year⁻¹ reported for runoff plots on a 10° cultivated slope at the Suining Station of Soil Erosion. The spatial pattern of soil erosion rates on the steep agricultural land showed that hoe tillage played an important role in soil redistribution along the slope. Also, traditional farming practices had a significant role in reducing soil loss, leading to a lower net erosion rate for the field.

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Citation Excerpt :
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¹: Project supported by the Ministry of Science and Technology of China (No. 2003CB415201), National Natural Science Foundation of China (No. 40671120), the International Atomic Energy Agency (Nos. 12322/RO and UK-12094), and the Young Scientist Foundation of Sichuan Province (No. 06ZQ026-030).

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Assessing Soil Erosion Rates on Manually-Tilled Hillslopes in the Sichuan Hilly Basin Using 137Cs and 210Pbex Measurements1

Abstract

Pedosphere

Journal of Environmental Radioactivity

Soil & Tillage Research

Catena

Soil & Tillage Research

Geomorphology

Soil & Tillage Research

Soil & Tillage Research

Geomorphology

Soil & Tillage Research

Soil & Tillage Research

Soil & Tillage Research

Catena

Application of Lead-210 to sedimentation studies

The role of tillage in soil redisbution on hillslopes

Soil Science

The relative contribution of soil tillage and overland flow erosion to soil redistribution on agricultural land

Earth Surf. Pro. Landforms

Determination of surface erosion of the small watersheds in the hilly area of purple soils in the upper reaches of the Yangtze River

Journal of Yangtze River Scientific Research Institute

Assessing Soil Erosion Rates on Manually-Tilled Hillslopes in the Sichuan Hilly Basin Using ¹³⁷Cs and ²¹⁰Pb_ex Measurements¹