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RESEARCH ARTICLE (Open Access)

Using environmental tracers to understand soil organic carbon and soil erosion on a steep slope hillslope in south-east Australia

G. R. Hancock https://orcid.org/0000-0002-1619-1265 A *
+ Author Affiliations
- Author Affiliations

A School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia.

* Correspondence to: Greg.Hancock@newcastle.edu.au

Handling Editor: Etelvino Novotny

Soil Research 61(6) 616-625 https://doi.org/10.1071/SR22263
Submitted: 17 December 2022  Accepted: 25 April 2023   Published: 26 May 2023

© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Context: It is well recognised that soil organic carbon (SOC) can be transported and deposited along the same pathways as those of soil erosion and deposition.

Aims: To examine the viability of environmental tracers 137Cs and unsupported 210Pb (210Pbex) as tools to inform soil erosion and deposition patterns as well as that of the distribution of SOC.

Methods: Multiple soil cores were collected along two transects of similar length and aspect in a steep-slope soil mantled environment in south-east Australia.

Key results: Average SOC concentration was high for both transects (~6% and 4%). SOC decreased moving downslope suggesting loss of SOC by erosion. There were strong and significant positive relationships of SOC with 137Cs and 210Pbex (both r > 0.77, P < 0.0001). At this site, SOC concentration appears related to erosion and deposition patterns.

Conclusion: The hillslope distribution of 137Cs and 210Pbex were very similar, indicating that both tracers were viable in this environment (r = 0.9, P < 0.0001). The different origins and half-lives of 137Cs and 210Pbex also demonstrate that the patterns of erosion and deposition are consistent at decadal time scales.

Implications: The use of 210Pbex provides an alternative method for understanding erosion and deposition patterns as well as that of SOC, given that the viability of 137Cs (half-life of 30.1 years) is now questionable due to no new replenishment.

Keywords: 137Cs, 210Pb, 210Pbex, carbon sequestration, lead-210, sediment transport, SOC, soil erosion.


References

Arrouays D, Vion I, Kicin JL (1995) Spatial analysis and modeling of topsoil carbon storage in temperate forest humic loamy soils of France. Soil Science 159, 191–198.
Spatial analysis and modeling of topsoil carbon storage in temperate forest humic loamy soils of France.Crossref | GoogleScholarGoogle Scholar |

Berhe AA, Harte J, Harden JW, Torn MS (2007) The significance of the erosion-induced terrestrial carbon sink. BioScience 57, 337–346.
The significance of the erosion-induced terrestrial carbon sink.Crossref | GoogleScholarGoogle Scholar |

Berhe AA, Arnold C, Stacy E, Lever R, McCorkle E, Araya SN (2014) Soil erosion controls on biogeochemical cycling of carbon and nitrogen. Nature Education Knowledge 5, 2

Beven KJ, Kirkby MJ (1979) A physically based, variable contributing area model of basin hydrology. Hydrological Sciences Bulletin 24, 43–69.
A physically based, variable contributing area model of basin hydrology.Crossref | GoogleScholarGoogle Scholar |

Bunzl K, Kretner R, Schramel P, Szeles M, Winkler R (1995) Speciation of 238U, 226Ra, 210Pb, 228Ra, and stable Pb in the soil near an exhaust ventilating shaft of a uranium mine. Geoderma 67, 45–53.
Speciation of 238U, 226Ra, 210Pb, 228Ra, and stable Pb in the soil near an exhaust ventilating shaft of a uranium mine.Crossref | GoogleScholarGoogle Scholar |

Campbell BL, Loughran RJ, Elliott GL (1988) A method for determining sediment budgets using caesium-137. 171–179.

Chen M, Willgoose GR, Saco PM (2015) Evaluation of the hydrology of the IBIS land surface model in a semi-arid catchment. Hydrological Processes 29, 653–670.
Evaluation of the hydrology of the IBIS land surface model in a semi-arid catchment.Crossref | GoogleScholarGoogle Scholar |

Doetterl S, Berhe AA, Nadeu E, Wang Z, Sommer M, Fiener P (2016) Erosion, deposition and soil carbon: a review of process-level controls, experimental tools and models to address C cycling in dynamic landscapes. Earth-Science Reviews 154, 102–122.
Erosion, deposition and soil carbon: a review of process-level controls, experimental tools and models to address C cycling in dynamic landscapes.Crossref | GoogleScholarGoogle Scholar |

Dorr H (1995) Application of 210Pb in soils. Journal of Paleolimnology 13, 157–168.
Application of 210Pb in soils.Crossref | GoogleScholarGoogle Scholar |

Fissore C, Dalzell BJ, Berhe AA, Voegtle M, Evans M, Wu A (2017) Influence of topography on soil organic carbon dynamics in a Southern California grassland. CATENA 149, 140–149.
Influence of topography on soil organic carbon dynamics in a Southern California grassland.Crossref | GoogleScholarGoogle Scholar |

Fukuyama T, Onda Y, Takenaka C, Walling DE (2008) Investigating erosion rates within a Japanese cypress plantation using Cs-137 and Pb-210ex measurements. Journal of Geophysical Research 113, F02007
Investigating erosion rates within a Japanese cypress plantation using Cs-137 and Pb-210ex measurements.Crossref | GoogleScholarGoogle Scholar |

Gaspar L, Navas A (2013) Vertical and lateral distributions of 137Cs in cultivated and uncultivated soils on Mediterranean hillslopes. Geoderma 207–208, 131–143.
Vertical and lateral distributions of 137Cs in cultivated and uncultivated soils on Mediterranean hillslopes.Crossref | GoogleScholarGoogle Scholar |

Gaspar L, Webster R, Navas A (2017) Fate of 210Pbex fallout in soil under forest and scrub of the central Spanish Pre-Pyrenees. European Journal of Soil Science 68, 259–269.
Fate of 210Pbex fallout in soil under forest and scrub of the central Spanish Pre-Pyrenees.Crossref | GoogleScholarGoogle Scholar |

Gaspar L, Quijano L, Lizaga I, Navas A (2019) Effects of land use on soil organic and inorganic C and N at 137Cs traced erosional and depositional sites in mountain agroecosystems. CATENA 181, 104058
Effects of land use on soil organic and inorganic C and N at 137Cs traced erosional and depositional sites in mountain agroecosystems.Crossref | GoogleScholarGoogle Scholar |

Grigal DF, Berguson WE (1998) Soil carbon changes associated with short-rotation systems. Biomass and Bioenergy 14, 371–377.
Soil carbon changes associated with short-rotation systems.Crossref | GoogleScholarGoogle Scholar |

Hancock GR, Wells T (2021) Predicting soil organic carbon movement and concentration using a soil erosion and landscape evolution model. Geoderma 382, 114759
Predicting soil organic carbon movement and concentration using a soil erosion and landscape evolution model.Crossref | GoogleScholarGoogle Scholar |

Hancock GR, Murphy D, Evans KG (2010) Hillslope and catchment scale soil organic carbon concentration: an assessment of the role of geomorphology and soil erosion in an undisturbed environment. Geoderma 155, 36–45.
Hillslope and catchment scale soil organic carbon concentration: an assessment of the role of geomorphology and soil erosion in an undisturbed environment.Crossref | GoogleScholarGoogle Scholar |

Hancock GR, Wells T, Martinez C, Dever C (2015) Soil erosion and tolerable soil loss: insights into erosion rates for a well-managed grassland catchment. Geoderma 237–238, 256–265.
Soil erosion and tolerable soil loss: insights into erosion rates for a well-managed grassland catchment.Crossref | GoogleScholarGoogle Scholar |

Hancock GR, Kunkel V, Wells T, Martinez C (2019) Soil organic carbon and soil erosion – understanding change at the large catchment scale. Geoderma 343, 60–71.
Soil organic carbon and soil erosion – understanding change at the large catchment scale.Crossref | GoogleScholarGoogle Scholar |

Hassink J (1997) The capacity of soils to preserve organic C and N by their association with clay and silt particles. Plant and Soil 191, 77–87.
The capacity of soils to preserve organic C and N by their association with clay and silt particles.Crossref | GoogleScholarGoogle Scholar |

Hazelton P, Murphy B (2007) ‘Interpreting soil test results: what to do all the numbers mean?’ (CSIRO Publishing: Melbourne, Vic., Australia)

He Q, Walling DE (1997) The distribution of fallout 137Cs and 210Pb in undisturbed and cultivated soils. Applied Radiation and Isotopes 48, 677–690.
The distribution of fallout 137Cs and 210Pb in undisturbed and cultivated soils.Crossref | GoogleScholarGoogle Scholar |

He Q, Walling DE, Wallbrink PJ (2002) Alternative methods and radionuclides for use in soil-erosion and sedimentation investigations. In ‘Handbook for the assessment of soil erosion and sedimentation using environmental radionuclides’. (Ed. F. Zapata) pp. 185–215. (Kluwer Academic Publishers: Dordrecht, Netherlands)

Hoyle FC, O’Leary RA, Murphy DV (2016) Spatially governed climate factors dominate management in determining the quantity and distribution of soil organic carbon in dryland agricultural systems. Scientific Reports 6, 31468
Spatially governed climate factors dominate management in determining the quantity and distribution of soil organic carbon in dryland agricultural systems.Crossref | GoogleScholarGoogle Scholar |

Jandl R, Rodeghiero M, Martinez C, Cotrufo MF, Bampa F, Van Wesemael B, Harrison RB, Guerrini IA, Richter Dd, Rustad L, Lorenz K, Chabbi A, Miglietta F (2014) Current status, uncertainty and future needs in soil organic carbon monitoring. Science of The Total Environment 468–469, 376–383.
Current status, uncertainty and future needs in soil organic carbon monitoring.Crossref | GoogleScholarGoogle Scholar |

Kato H, Onda Y, Tanaka Y (2010) Using 137Cs and 210Pbex measurements to estimate soil redistribution rates on semi-arid grassland in Mongolia. Geomorphology 114, 508–519.
Using 137Cs and 210Pbex measurements to estimate soil redistribution rates on semi-arid grassland in Mongolia.Crossref | GoogleScholarGoogle Scholar |

Kirkels FMSA, Cammeraat LH, Kuhn NJ (2014) The fate of soil organic carbon upon erosion, transport and deposition in agricultural landscapes – a review of different concepts. Geomorphology 226, 94–105.
The fate of soil organic carbon upon erosion, transport and deposition in agricultural landscapes – a review of different concepts.Crossref | GoogleScholarGoogle Scholar |

Knighton D (1998) ‘Fluvial forms and processes: a new perspective.’ (Routledge: Abingdon, Oxon, UK)

Kovac M, Lawrie JW (1991) Soil landscapes of the singleton 1:250 000 sheet. p. 456. Soil Conservation Service of NSW, Sydney, Australia.

Krause AK, Loughran RJ, Kalma JD (2003) The use of caesium-137 to assess surface soil erosion status in a water-supply catchment in the Hunter Valley, New South Wales, Australia. Australian Geographical Studies 41, 73–84.
The use of caesium-137 to assess surface soil erosion status in a water-supply catchment in the Hunter Valley, New South Wales, Australia.Crossref | GoogleScholarGoogle Scholar |

Kuhn NJ, Hoffmann T, Schwanghart W, Dotterweich M (2009) Agricultural soil erosion and global carbon cycle: controversy over? Earth Surface Processes and Landforms 34, 1033–1038.
Agricultural soil erosion and global carbon cycle: controversy over?Crossref | GoogleScholarGoogle Scholar |

Kunkel V, Wells T, Hancock GR (2016) Soil temperature dynamics at the catchment scale. Geoderma 273, 32–44.
Soil temperature dynamics at the catchment scale.Crossref | GoogleScholarGoogle Scholar |

Kunkel V, Hancock GR, Wells T (2019) Large catchment-scale spatiotemporal distribution of soil organic carbon. Geoderma 334, 175–185.
Large catchment-scale spatiotemporal distribution of soil organic carbon.Crossref | GoogleScholarGoogle Scholar |

Lal R (2001) Soil degradation by erosion. Land Degradation & Development 12, 519–539.
Soil degradation by erosion.Crossref | GoogleScholarGoogle Scholar |

Lal R (2003) Soil erosion and the global carbon budget. Environment International 29, 437–450.
Soil erosion and the global carbon budget.Crossref | GoogleScholarGoogle Scholar |

Lal R (2004) Soil carbon sequestration to mitigate climate change. Geoderma 123, 1–22.
Soil carbon sequestration to mitigate climate change.Crossref | GoogleScholarGoogle Scholar |

Lal R (2019) Accelerated soil erosion as a source of atmospheric CO2. Soil and Tillage Research 188, 35–40.
Accelerated soil erosion as a source of atmospheric CO2.Crossref | GoogleScholarGoogle Scholar |

Lewis DM (1977) The use of 210Pb as a heavy metal tracer in the Susquehanna River system. Geochimica et Cosmochimica Acta 41, 1557–1564.
The use of 210Pb as a heavy metal tracer in the Susquehanna River system.Crossref | GoogleScholarGoogle Scholar |

Li Y, Poesen J, Yang JC, Fu B, Zhang JH (2003) Evaluating gully erosion using 137Cs and 210Pb/137Cs ratio in a reservoir catchment. Soil and Tillage Research 69, 107–115.
Evaluating gully erosion using 137Cs and 210Pb/137Cs ratio in a reservoir catchment.Crossref | GoogleScholarGoogle Scholar |

Li Y, Zhang QW, Reicosky DC, Bai LY, Lindstrom MJ, Li L (2006) Using 137Cs and 210Pbex for quantifying soil organic carbon redistribution affected by intensive tillage on steep slopes. Soil and Tillage Research 86, 176–184.
Using 137Cs and 210Pbex for quantifying soil organic carbon redistribution affected by intensive tillage on steep slopes.Crossref | GoogleScholarGoogle Scholar |

Longmore ME, O’Leary BM, Rose CW, Chandica AL (1983) Mapping soil erosion and accumulation with the fallout isotope caesium-137. Soil Research 21, 373–385.
Mapping soil erosion and accumulation with the fallout isotope caesium-137.Crossref | GoogleScholarGoogle Scholar |

Loughran RJ (1994) The use of the environmental isotope caesium-137 for soil erosion and sedimentation studies. Trends in Hydrology 1, 149–167.

Loughran RJ, Pennock DJ, Walling DE (2002) Spatial distribution of caesium-137. In ‘Handbook for the assessment of soil erosion and sedimentation using environmental radionuclides’. (Ed. F. Zapata) pp. 97–109. (Kluwer Academic Publishers: Dordrecht, Netherlands)

Loughran RJ, Elliott GL, McFarlane DJ, Campbell BL (2004) A survey of soil erosion in Australia using caesium-137. Australian Geographical Studies 42, 221–233.
A survey of soil erosion in Australia using caesium-137.Crossref | GoogleScholarGoogle Scholar |

Mabit L, Bernard C, Makhlouf M, Laverdière MR (2008) Spatial variability of erosion and soil organic matter content estimated from 137Cs measurements and geostatistics. Geoderma 145, 245–251.
Spatial variability of erosion and soil organic matter content estimated from 137Cs measurements and geostatistics.Crossref | GoogleScholarGoogle Scholar |

Mabit L, Klik A, Benmansour M, Toloza A, Geisler A, Gerstmann UC (2009) Assessment of erosion and deposition rates within an Austrian agricultural watershed by combining 137Cs, 210Pbex and conventional measurements. Geoderma 150, 231–239.
Assessment of erosion and deposition rates within an Austrian agricultural watershed by combining 137Cs, 210Pbex and conventional measurements.Crossref | GoogleScholarGoogle Scholar |

Mabit L, Benmansour M, Abril JM, Walling DE, Meusburger K, Iurian AR, Bernard C, Tarján S, Owens PN, Blake WH, Alewell C (2014) Fallout 210Pb as a soil and sediment tracer in catchment sediment budget investigations: a review. Earth-Science Reviews 138, 335–351.
Fallout 210Pb as a soil and sediment tracer in catchment sediment budget investigations: a review.Crossref | GoogleScholarGoogle Scholar |

Martinez C, Hancock GR, Kalma JD (2009) Comparison of fallout radionuclide (caesium-137) and modelling approaches for the assessment of soil erosion rates for an uncultivated site in south-eastern Australia. Geoderma 151, 128–140.
Comparison of fallout radionuclide (caesium-137) and modelling approaches for the assessment of soil erosion rates for an uncultivated site in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Martinez C, Hancock GR, Kalma JD (2010) Relationships between 137Cs and soil organic carbon (SOC) in cultivated and never-cultivated soils: an Australian example. Geoderma 158, 137–147.
Relationships between 137Cs and soil organic carbon (SOC) in cultivated and never-cultivated soils: an Australian example.Crossref | GoogleScholarGoogle Scholar |

Mcfarlane DJ, Loughran RJ, Campbell BL (1992) Soil erosion of agricultural land in Western Australia estimated by cesium-137. Soil Research 30, 533–546.
Soil erosion of agricultural land in Western Australia estimated by cesium-137.Crossref | GoogleScholarGoogle Scholar |

Mills GA, Webb R, Davidson NE, Kepert J, Seed A, Abbs D (2010) The Pasha Bulker east coast low of 8 June 2007. Centre for Australian Weather and Climate Research technical report 23. p. 62. Centre for Australian Weather and Climate Research.

Minasny B, Malone BP, McBratney AB, Angers DA, Arrouays D, Chambers A, Chaplot V, Chen Z-S, Cheng K, Das BS, Field DJ, Gimona A, Hedley CB, Hong SY, Mandal B, Marchant BP, Martin M, McConkey BG, Mulder VL, O’Rourke S, Richer-de-Forges AC, Odeh I, Padarian J, Paustian K, Pan G, Poggio L, Savin I, Stolbovoy V, Stockmann U, Sulaeman Y, Tsui C-C, Vågen T-G, van Wesemael B, Winowiecki L (2017) Soil carbon 4 per mille. Geoderma 292, 59–86.
Soil carbon 4 per mille.Crossref | GoogleScholarGoogle Scholar |

Moore ID, Gessler PE, Nielsen GA, Peterson GA (1993) Soil attribute prediction using terrain analysis. Soil Science Society of America Journal 57, 443–452.
Soil attribute prediction using terrain analysis.Crossref | GoogleScholarGoogle Scholar |

Murphy BW (2015) Impact of soil organic matter on soil properties – a review with emphasis on Australian soils. Soil Research 53, 605–635.
Impact of soil organic matter on soil properties – a review with emphasis on Australian soils.Crossref | GoogleScholarGoogle Scholar |

Müller T, Höper H (2004) Soil organic matter turnover as a function of the soil clay content: consequences for model applications. Soil Biology and Biochemistry 36, 877–888.
Soil organic matter turnover as a function of the soil clay content: consequences for model applications.Crossref | GoogleScholarGoogle Scholar |

Oades JM (1988) The retention of organic matter in soils. Biogeochemistry 5, 35–70.
The retention of organic matter in soils.Crossref | GoogleScholarGoogle Scholar |

Olley J, Burton J, Smolders K, Pantus F, Pietsch T (2013) The application of fallout radionuclides to determine the dominant erosion process in water supply catchments of subtropical South-east Queensland, Australia. Hydrological Processes 27, 885–895.
The application of fallout radionuclides to determine the dominant erosion process in water supply catchments of subtropical South-east Queensland, Australia.Crossref | GoogleScholarGoogle Scholar |

O’Brien SL, Jastrow JD, Grimley DA, Gonzalez-Meler MA (2015) Edaphic controls on soil organic carbon stocks in restored grasslands. Geoderma 251–252, 117–123.
Edaphic controls on soil organic carbon stocks in restored grasslands.Crossref | GoogleScholarGoogle Scholar |

Özden B, Uğur A, Esetlili T, Esetlili BC, Kurucu Y (2013) Assessment of the effects of physical–chemical parameters on 210Po and 210Pb concentrations in cultivated and uncultivated soil from different areas. Geoderma 192, 7–11.
Assessment of the effects of physical–chemical parameters on 210Po and 210Pb concentrations in cultivated and uncultivated soil from different areas.Crossref | GoogleScholarGoogle Scholar |

Pennock DJ, Appleby PG (2002) Site selection and sampling design. In ‘Handbook for the assessment of soil erosion and sedimentation using environmental radionuclides’. (Ed. F Zapata) pp. 219. (Kluwer Academic Publishers: Dordrecht, Netherlands)

Percival HJ, Parfitt RL, Scott NA (2000) Factors controlling soil carbon levels in New Zealand grasslands is clay content important? Soil Science Society of America Journal 64, 1623–1630.
Factors controlling soil carbon levels in New Zealand grasslands is clay content important?Crossref | GoogleScholarGoogle Scholar |

Quinton JN, Govers G, Van Oost K, Bardgett RD (2010) The impact of agricultural soil erosion on biogeochemical cycling. Nature Geoscience 3, 311–314.
The impact of agricultural soil erosion on biogeochemical cycling.Crossref | GoogleScholarGoogle Scholar |

Ritchie JC, McHenry JR (1975) Fallout Cs-137: a tool in conservation research. Journal of Soil and Water Conservation 30, 283–286.

Ruiz Sinoga JD, Pariente S, Diaz AR, Martinez Murillo JF (2012) Variability of relationships between soil organic carbon and some soil properties in Mediterranean rangelands under different climatic conditions (South of Spain). CATENA 94, 17–25.
Variability of relationships between soil organic carbon and some soil properties in Mediterranean rangelands under different climatic conditions (South of Spain).Crossref | GoogleScholarGoogle Scholar |

Rumpel C, Kögel-Knabner I (2011) Deep soil organic matter – a key but poorly understood component of terrestrial C cycle. Plant and Soil 338, 143–158.
Deep soil organic matter – a key but poorly understood component of terrestrial C cycle.Crossref | GoogleScholarGoogle Scholar |

Rüdiger C, Hancock G, Hemakumara HM, Jacobs B, Kalma JD, Martinez C, Thyer M, Walker JP, Wells T, Willgoose GR (2007) Goulburn River experimental catchment data set. Water Resources Research 43, W10403
Goulburn River experimental catchment data set.Crossref | GoogleScholarGoogle Scholar |

Schwanghart W, Jarmer T (2011) Linking spatial patterns of soil organic carbon to topography – A case study from south-eastern Spain. Geomorphology 126, 252–263.
Linking spatial patterns of soil organic carbon to topography – A case study from south-eastern Spain.Crossref | GoogleScholarGoogle Scholar |

Singh M, Sarkar B, Biswas B, Churchman J, Bolan NS (2016) Adsorption-desorption behavior of dissolved organic carbon by soil clay fractions of varying mineralogy. Geoderma 280, 47–56.
Adsorption-desorption behavior of dissolved organic carbon by soil clay fractions of varying mineralogy.Crossref | GoogleScholarGoogle Scholar |

Smith RT, Atkinson K (1975) ‘Techniques in pedology: a handbook for environmental and resource studies.’ (Paul Elek: London, UK)

Story R, Galloway R, van de Graff R, Tweedie AD (1963) General report on the lands of the Hunter Valley. CSIRO Land Research Series No. 8. Commonwealth Scientific and Industrial Research Organization, Australia.

Taylor A, Blake WH, Smith HG, Mabit L, Keith-Roach MJ (2013) Assumptions and challenges in the use of fallout beryllium-7 as a soil and sediment tracer in river basins. Earth-Science Reviews 126, 85–95.
Assumptions and challenges in the use of fallout beryllium-7 as a soil and sediment tracer in river basins.Crossref | GoogleScholarGoogle Scholar |

Teramage MT, Onda Y, Kato H, Wakiyama Y, Mizugaki S, Hiramatsu S (2013) The relationship of soil organic carbon to 210Pbex and 137Cs during surface soil erosion in a hillslope forested environment. Geoderma 192, 59–67.
The relationship of soil organic carbon to 210Pbex and 137Cs during surface soil erosion in a hillslope forested environment.Crossref | GoogleScholarGoogle Scholar |

Teramage MT, Onda Y, Wakiyama Y, Kato H, Kanda T, Tamura K (2015) Atmospheric 210Pb as a tracer for soil organic carbon transport in a coniferous forest. Environmental Science: Processes & Impacts 17, 110
Atmospheric 210Pb as a tracer for soil organic carbon transport in a coniferous forest.Crossref | GoogleScholarGoogle Scholar |

Wallbrink PJ, Olley JM, Murray AS (1994) Measuring soil movement using 137Cs: implications of reference site variability. In ‘Variability in stream erosion and sediment transport. Proceedings of the Canberra symposium’. December 1994, IAHS Publication no. 224. pp. 95–102. (IAHS)

Walling DE, He Q (1999) Improved models for estimating soil erosion rates from cesium-137 measurements. Journal of Environmental Quality 28, 611–622.
Improved models for estimating soil erosion rates from cesium-137 measurements.Crossref | GoogleScholarGoogle Scholar |

Walling DE, He Q (2001) Models for converting 137Cs measurements to estimates of soil redistribution rates on cultivated and uncultivated soils, estimating bomb-derived 137Cs reference inventories (including software for model implementation). A contribution to the IAEA Coordinated Research Programmes on Soil Erosion (D1.50.05) and Sedimentation (F3.10.01). p. 32. University of Exeter, UK.

Walling DE, Collins AL, Sichingabula HM (2003) Using unsupported lead-210 measurements to investigate soil erosion and sediment delivery in a small Zambian catchment. Geomorphology 52, 193–213.
Using unsupported lead-210 measurements to investigate soil erosion and sediment delivery in a small Zambian catchment.Crossref | GoogleScholarGoogle Scholar |

Walling DE, Zhang Y, He Q (2011) Models for deriving estimates of erosion and deposition rates from fallout radionuclide (caesium-137, excess lead-201, and beryllium-7) measurements and the development of user friendly software for model implementation. In ‘Impact of soil conservation measures on erosion control and soil quality’. IAEA-TECDOC-1665. pp. 11–33. (International Atomic Energy Agency: Vienna, Austria)

Wei H, Guenet B, Vicca S, Nunan N, Asard H, AbdElgawad H, Shen W, Janssens IA (2014) High clay content accelerates the decomposition of fresh organic matter in artificial soils. Soil Biology and Biochemistry 77, 100–108.
High clay content accelerates the decomposition of fresh organic matter in artificial soils.Crossref | GoogleScholarGoogle Scholar |

Wells T, Hancock G (2014) Comparison of vertical transport of 137Cs and organic carbon in agricultural cracking soils. Geoderma 214–215, 228–238.
Comparison of vertical transport of 137Cs and organic carbon in agricultural cracking soils.Crossref | GoogleScholarGoogle Scholar |

Wells T, Hancock GR, Dever C, Murphy D (2012) Prediction of vertical soil organic carbon profiles using soil properties and environmental tracer data at an untilled site. Geoderma 170, 337–346.
Prediction of vertical soil organic carbon profiles using soil properties and environmental tracer data at an untilled site.Crossref | GoogleScholarGoogle Scholar |

Zapata F (2003) Introduction. Soil and Tillage Research 69, 1–2.
Introduction.Crossref | GoogleScholarGoogle Scholar |

Zapata F, Garcia-Agudo E, Ritchie JC, Appleby PG (2002) Chapter 1: Introduction. In ‘Handbook for the assessment of soil erosion and sedimentation using environmental radionuclides’. (Ed. F Zapata) pp. 1–13. (Kluwer Academic Publishers: Dordrecht, Netherlands)

Zhang X, Qi Y, Walling DE, He X, Wen A, Fu J (2006) A preliminary assessment of the potential for using 210Pbex measurement to estimate soil redistribution rates on cultivated slopes in the Sichuan Hilly Basin of China. CATENA 68, 1–9.
A preliminary assessment of the potential for using 210Pbex measurement to estimate soil redistribution rates on cultivated slopes in the Sichuan Hilly Basin of China.Crossref | GoogleScholarGoogle Scholar |