Author
Jean Riotte
Other affiliations: University of Toulouse, Paul Sabatier University, Centre national de la recherche scientifique ...read more
Bio: Jean Riotte is an academic researcher from Indian Institute of Science. The author has contributed to research in topics: Drainage basin & Weathering. The author has an hindex of 24, co-authored 80 publications receiving 2241 citations. Previous affiliations of Jean Riotte include University of Toulouse & Paul Sabatier University.
Papers published on a yearly basis
Papers
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TL;DR: Goldstein and Stirling as mentioned in this paper presented the main directions taken in these domains over the last decade, including the analytical developments made in the measurement of the medium half-life nuclides of 238U series (i.e., 234U-230Th-226Ra) in the mid-1980s, namely, the use of thermal ionisation mass spectrometry (TIMS) (e.g., Chen et al. 1986, Edwards et al 1987, Cohen et al 1991, Chabaux 1993,Chabaux et al 1994) and more recently the use
Abstract: The potential of radioactive disequilibria as tracers and chronometers of weathering processes has been recognised since the 1960’s (e.g., Rosholt et al. 1966; Hansen and Stout 1968). This interest results from the dual property of the nuclides of the U and Th radioactive series (1) to be fractionated during water-rock interactions and (2) to have radioactive periods of the same order of magnitude as the time constants of many weathering processes and chemical transfers to ground and river waters. Therefore, the study of radioactive disequilibria in surface environments should help to bring information about the nature, the intensity but also the time-scale of the water-rock interactions produced during weathering and related chemical transfers. These different properties have justified many of the studies on U-Th series in weathering profiles and river waters.
Rosholt (1982), Scott (1982) and Osmond and Ivanovich (1992) gave a synthesis of the studies of U-series in weathering and surface hydrology up to the 1980’s and the 1990’s respectively. Here, we present the main directions taken in these domains over the last decade. They were partly stimulated by the analytical developments made in the measurement of the medium half-life nuclides of 238U series (i.e., 234U-230Th-226Ra) in the mid-1980’s, namely, the use of thermal ionisation mass spectrometry (TIMS) (e.g., Chen et al. 1986; Edwards et al. 1987; Cohen et al. 1991; Chabaux 1993;Chabaux et al. 1994) and more recently the use of MC ICP-MS (Turner et al. 2001; Robinson et al. 2002) for U and Th isotope analysis. Details of these developments are given in this volume (Goldstein and Stirling 2003). Compared to the radioactive counting methods previously used, the new techniques permit (1) a reduction by one order of magnitude or more of the size of the sample required for …
306 citations
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TL;DR: In this article, the results of (234U/238U) activity ratios along the stream indicate a clear dependence between the surface waters and the different types of rocks forming the watershed, with near equilibrium values for the waters draining granites and high (1.4) disequilibria for those flowing over carbonates.
155 citations
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TL;DR: In this article, the extraction yields for these samples were calculated using presumable conservative elements (Fe, Ca, Mg, K, Na and Mn) and vary from 95.4% to 99.4%.
154 citations
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Paris Diderot University1, University of Grenoble2, University of Rennes3, Australian National Drag Racing Association4, Centre national de la recherche scientifique5, University of Paris6, Aix-Marseille University7, Université Paris-Saclay8, University of Avignon9, University of Caen Lower Normandy10, École Normale Supérieure11, Agrocampus Ouest12, Ecolab13, SupAgro14, University of Yaoundé15, Mines ParisTech16, Indian Institute of Science17, Higher University of San Andrés18
TL;DR: The OZCAR-RI project as discussed by the authors is a network of instrumented sites, bringing together 21 pre-existing research observatories monitoring different compartments of the zone situated between “the rock and the sky,” the Earth's skin or critical zone (CZ), over the long term.
Abstract: The French critical zone initiative, called OZCAR (Observatoires de la Zone Critique–Application et Recherche or Critical Zone Observatories–Application and Research) is a National Research Infrastructure (RI). OZCAR-RI is a network of instrumented sites, bringing together 21 pre-existing research observatories monitoring different compartments of the zone situated between “the rock and the sky,” the Earth’s skin or critical zone (CZ), over the long term. These observatories are regionally based and have specific initial scientific questions, monitoring strategies, databases, and modeling activities. The diversity of OZCAR-RI observatories and sites is well representative of the heterogeneity of the CZ and of the scientific communities studying it. Despite this diversity, all OZCAR-RI sites share a main overarching mandate, which is to monitor, understand, and predict (“earthcast”) the fluxes of water and matter of the Earth’s near surface and how they will change in response to the “new climatic regime.” The vision for OZCAR strategic development aims at designing an open infrastructure, building a national CZ community able to share a systemic representation of the CZ , and educating a new generation of scientists more apt to tackle the wicked problem of the Anthropocene. OZCAR articulates around: (i) a set of common scientific questions and cross-cutting scientific activities using the wealth of OZCAR-RI observatories, (ii) an ambitious instrumental development program, and (iii) a better interaction between data and models to integrate the different time and spatial scales. Internationally, OZCAR-RI aims at strengthening the CZ community by providing a model of organization for pre-existing observatories and by offering CZ instrumented sites. OZCAR is one of two French mirrors of the European Strategy Forum on Research Infrastructure (eLTER-ESFRI) project.
119 citations
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TL;DR: In this article, the authors proposed a method to assess the long-term chemical weathering mass balance for a regolith developed on a heterogeneous silicate substrate at the small experimental watershed scale by adopting a combined approach of geophysics, geochemistry and mineralogy.
119 citations
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01 Jan 2007
TL;DR: The Third edition of the Kirk-Othmer encyclopedia of chemical technology as mentioned in this paper was published in 1989, with the title "Kirk's Encyclopedia of Chemical Technology: Chemical Technology".
Abstract: 介绍了Kirk—Othmer Encyclopedia of Chemical Technology(化工技术百科全书)(第五版)电子图书网络版数据库,并对该数据库使用方法和检索途径作出了说明,且结合实例简单地介绍了该数据库的检索方法。
2,666 citations
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TL;DR: In this paper, the chemical weathering of basalts and the flux of carbon transferred from the atmosphere to the ocean during this major process at the surface of the Earth were investigated.
762 citations
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TL;DR: Global observations of water table depth compiled from government archives and literature are presented to fill in data gaps and infer patterns and processes using a groundwater model forced by modern climate, terrain, and sea level.
Abstract: Shallow groundwater affects terrestrial ecosystems by sustaining river base-flow and root-zone soil water in the absence of rain, but little is known about the global patterns of water table depth and where it provides vital support for land ecosystems We present global observations of water table depth compiled from government archives and literature, and fill in data gaps and infer patterns and processes using a groundwater model forced by modern climate, terrain, and sea level Patterns in water table depth explain patterns in wetlands at the global scale and vegetation gradients at regional and local scales Overall, shallow groundwater influences 22 to 32% of global land area, including ~15% as groundwater-fed surface water features and 7 to 17% with the water table or its capillary fringe within plant rooting depths
691 citations
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TL;DR: This is the first review regarding biogeochemical behaviour of heavy metals in atmosphere-plant system and summarizes the mechanisms involved in foliar heavy metal uptake, transfer, compartmentation, toxicity and in plant detoxification.
654 citations
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Environment Canada1, National Oceanic and Atmospheric Administration2, Norwegian Institute for Air Research3, University of East Anglia4, World Meteorological Organization5, North-West University6, CSIRO Marine and Atmospheric Research7, National Institute for Space Research8, Tokyo University of Agriculture and Technology9, Russian Academy of Sciences10, Cornell University11, Indian Institute of Tropical Meteorology12, Ontario Ministry of the Environment13
TL;DR: The Addendum contains supplementary material for the full version of this article as discussed by the authors. It can be viewed electronically at http://dx.doi.org/10.1016/j.atmosenv.2014.02.017
642 citations