DOI: 10.1016/j.earscirev.2021.103542
论文题名: Mapping the spatial distribution of global 137Cs fallout in soils of South America as a baseline for Earth Science studies
作者: Chaboche P.-A. ; Saby N.P.A. ; Laceby J.P. ; Minella J.P.G. ; Tiecher T. ; Ramon R. ; Tassano M. ; Cabral P. ; Cabrera M. ; da Silva Y.J.A.B. ; Lefevre I. ; Evrard O.
刊名: Earth Science Reviews
ISSN: 00128252
出版年: 2021
卷: 214 语种: 英语
中文关键词: Caesium-137
; Digital soil mapping
; Reference soil sites
; Soil erosion
; Soil redistribution rates
英文关键词: cesium isotope
; digital mapping
; Earth science
; inventory
; quantitative analysis
; soil chemistry
; soil erosion
; soil profile
; spatial distribution
; Brazil
; Chile
英文摘要: Owing to the rapid expansion of agriculture in South America in recent decades, soil erosion and fine sediment supply to river networks, which lead to deleterious on-site and off-site environmental impacts, are exacerbated in intensively cultivated catchments. Measuring soil inventories of bomb-derived fallout radiocesium (137Cs) bound to fine particles is one of the few techniques available to reconstruct soil redistribution rates and evaluate the sustainability of farming practices over the recent phase of agricultural intensification (1960s–2020). However, information about the spatial distribution of 137Cs fallout across the soils of South America remains scarce, and the published data has not been synthesized at the scale of this subcontinent so far. The objective of the current research is therefore to quantify and map the initial 137Cs fallout at the scale of South America, based on the compilation of published 137Cs inventories, additional measurements conducted on undisturbed soil profiles and digital soil mapping as this baseline information may be useful for a wide range of Earth Science applications. A database of 137Cs inventories at 96 reference sites (i.e. areas without soil erosion nor accumulation) has been compiled for a variety of soil profiles (Argentina = 10, Brazil = 34, Chile = 46, Uruguay = 5, French Guiana = 1) located between 5.3° North latitude and 53° South latitude. The spatial distribution of 137Cs fallout was shown to be highly latitude-dependent, with a maximum in the 30–50° South latitude band. There were higher fallout levels than expected between 20 and 60° South latitude compared to the previous estimations made by UNSCEAR. A partial least square regression approach based on rainfall data and geographical information as covariates was used to create a baseline map of 137Cs fallout in soils of continental South America. This baseline map provides a powerful reference dataset to anticipate the order of magnitude of 137Cs inventories in undisturbed soil profiles collected in Brazil and Southern Chile and for numerous other applications in Earth Sciences. The potential application of the 137Cs inventory technique in countries of South America in general, and in regions with vulnerable ecosystems threatened by the expansion of agricultural activities in particular, is discussed in light of this comprehensive literature review. Furthermore, the regions (i.e. the North-Western part of the continent) where additional samples should be collected in priority to improve this baseline map are outlined. Our results demonstrate that 137Cs inventories are sufficiently high to investigate soil redistribution rates in most of South American countries where detectable levels of 137Cs can be expected to be found in sites exposed to erosion. © 2021 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/166352
Appears in Collections: 气候变化与战略
There are no files associated with this item.
作者单位: Laboratoire des Sciences du Climat et de l'Environnement (LSCE/IPSL), Unité Mixte de Recherche 8212 (CEA-CNRS-UVSQ), Université Paris-Saclay, Gif-sur-Yvette, France; INRAE, Unité Infosol US1106, Orléans 2, France; Alberta Environment and Parks, 3535 Research Rd NW, Calgary, AB T2L 2K8, Canada; Department of Soils, Federal University of Santa Maria, Santa Maria, 97105-900, Brazil; Department of Soil Science, Federal University of Rio Grande do Sul, Bento Gonçalves Ave. 7712, Porto Alegre, RS 91540-000, Brazil; Graduate Program in Soil Science, Federal University of Rio Grande do Sul, Bento Gonçalves Ave, Porto Alegre, RS 91540-000, Brazil; Laboratorio de Radioquímica, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Agronomy Department, Federal University of Piaui (UFPI), Planalto Horizonte, Bom Jesus, PI 64900-000, Brazil
Recommended Citation:
Chaboche P.-A.,Saby N.P.A.,Laceby J.P.,et al. Mapping the spatial distribution of global 137Cs fallout in soils of South America as a baseline for Earth Science studies[J]. Earth Science Reviews,2021-01-01,214