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Anglade, J.; Billen, G.; Garnier, J.. |
This work suggests that Soil Surface Balance is a robust indicator to compare the performances of organic agriculture with those of conventional agriculture, even strictly following the rules of rational and optimised application of fertilisers. The results of long term nitrogen budget calculation brought us to seriously reconsider the relevance of the need to increase crop yields, and more broadly to reconsider cropping patterns and production systems. In terms of policy levers for mitigating nitrogen contamination of water resources, only the shift to organic farming provides a possible way to reconcile agricultural production and water quality. Further, this view points out the need for specific measures to encourage more mixed farming approach to... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Air and water emissions; Farm nutrient management. |
Ano: 2013 |
URL: http://orgprints.org/24519/1/24519.pdf |
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Ratie, G.; Garnier, J.; Calmels, D.; Vantelon, D.; Guimaraes, E.; Monvoisin, G.; Nouet, J.; Ponzevera, Emmanuel; Quantin, C.. |
Ultramafic (UM) rocks are known to be nickel (Ni) rich and to weather quickly, which makes them a good candidate to look at the Ni isotope systematics during weathering processes at the Earth’s surface. The present study aims at identifying the Ni solid speciation and discussing the weathering processes that produce Ni isotope fractionation in two deep laterite profiles under tropical conditions (Barro Alto, Goiás State, Brazil). While phyllosilicates and to a lower extent goethite are the main Ni-bearing phases in the saprolitic part of the profile, iron (Fe) oxides dominate the Ni budget in the lateritic unit. Nickel isotopic composition (δ60Ni values) has been measured in each unit of the regolith, i.e., rock, saprock, saprolite and laterite (n=52).... |
Tipo: Text |
Palavras-chave: Nickel cycle; Lateritic regolith; Nickel isotopes; XANES; Ultramafic environment; Weathering. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00436/54712/56149.pdf |
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Ratie, G.; Quantin, C.; Jouvin, D.; Calmels, D.; Ettler, V.; Sivry, Y.; Cruz Vieira, L.; Ponzevera, Emmanuel; Garnier, J.. |
Nickel isotope ratios were measured in ores, fly ash, slags and FeNi samples from two metallurgical plants located in the Goiás State, Brazil (Barro Alto, Niquelândia). This allowed investigating the mass-dependent fractionation of Ni isotopes during the Ni-laterite ore smelting and refining. Feeding material exhibits a large range of δ60Ni values (from 0.02 ± 0.10 ‰ to 0.20 ± 0.05 ‰, n=7), explained by the diversity of Ni-bearing phases, and the average of δ60Nifeeding materials was found equal to 0.08 ± 0.08‰ (2SD, n=7). Both δ60Ni values of fly ash (δ60Ni = 0.07 ± 0.07‰, n=10) and final FeNi produced (0.05 ± 0.02 ‰, n=2) were not significantly different from the feeding materials ones. These values are consistent with the very high production yield of... |
Tipo: Text |
Palavras-chave: Nickel; Isotope; Smelting; Refining; Source; Soil. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00278/38961/37501.pdf |
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Benoit, M.; Garnier, J.; Billen, G.; Mercier, B.; Azougui, A.. |
A great challenge to science is to elucidate how agriculture can feed the increasing world population without damaging the environment, while preserving other resources such as freshwater. In the Seine basin, characterised by intensive agriculture, most of surface and underground water is contaminated by nitrate. Conventional agriculture has regularly increased the use of industrial fertilisers since the WWII, leading to high nitrogen leaching, as shown by lysimeters or suction cup measurements. Such measurements are very scarce for other agricultural systems such as organic farming (Hansen et al. 2000; Haas et al. 2002; Mondelaers et al. 2009). The goal of our study is to investigate nitrogen leaching from organic agriculture, taking into account complete... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Nutrient turnover; Air and water emissions. |
Ano: 2013 |
URL: http://orgprints.org/24518/1/24518.pdf |
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Desmit, X.; Thieu, V.; Billen, G.; Campuzano, F.; Duliere, V.; Garnier, J.; Lassaletta, L.; Menesguen, Alain; Neves, R.; Pinto, L.; Silvestre, M.; Sobrinho, J. L.; Lacroix, G.. |
Marine eutrophication in the North-East Atlantic (NEA) strongly relies on nutrient enrichment at the river outlets, which is linked to human activities and land use in the watersheds. The question is whether human society can reduce its nutrient emissions by changing land use without compromising food security. A new version of Riverstrahler model (pyNuts-Riverstrahler) was designed to estimate the point and diffuse nutrient emissions (N, P, Si) to the rivers depending on land use in the watersheds across a large domain (Western Europe agro-food systems, waste water treatment). The loads from the river model have been used as inputs to three marine ecological models (PCOMS, ECO-MARS3D, MIRO&CO) covering together a large part of the NEA from the Iberian... |
Tipo: Text |
Palavras-chave: North-East Atlantic; Eutrophication; Model scenarios; Land-sea continuum; Land use; Pristine; Management support. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00438/55007/56426.pdf |
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Ratie, G.; Quantin, C.; Maia De Freitas, A.; Echevarria, G.; Ponzevera, Emmanuel; Garnier, J.. |
Ultramafic derived soils are characterized by low nutrient soils, a low Ca:Mg ratio, and high metal contents such as Ni, Co and Cr. The vegetation growing on these soils is highly adapted and includes both Ni hyperaccumulator and accumulator species. Today, approximately 530 Ni hyperaccumulator species are listed worldwide and the Ni concentration can be extremely high, e.g. up to 25% in latex from Pycnandra acuminata (Sapotaceae), a tree found in New Caledonia. The aim of this study is to identify the potential role of Ni hyperaccumulator plants in the Ni biogeochemical cycle at the soil surface by using Ni isotopes. A set of Ni hyperaccumulator and Ni accumulator plants as well as topsoils were sampled on the Barro Alto and Niquelândia ultramafic... |
Tipo: Text |
Palavras-chave: Nickel; Isotope; Ni hyperaccumulator species; Ultramafic environment. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00464/57565/59740.pdf |
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