Refinar búsqueda
Resultados 1-5 de 5
The pesticide chlordecone is trapped in the tortuous mesoporosity of allophane clays
2018
Woignier, Thierry | Clostre, Florence | Fernandes, Paula | Soler, Alain | Rangon, Luc | Sastre-Conde, Maria Isabel | Jannoyer-Lesueur, Magalie
Some volcanic soils like andosols contain short-range order nanoclays (allophane) which build aggregates with a tortuous and fractal microstructure. The aim of the work was to study the influence of the microstructure and mesoporosity of the allophane aggregates on the pesticide chlordecone retention in soils. Our study shows that the allophane microstructure favors pollutants accumulation and sequestration in soils. We put forth the importance of the mesoporous microstructure of the allophane aggregates for pollutant trapping in andosols. We show that the soil contamination increases with the allophane content but also with the mesopore volume, the tortuosity, and the size of the fractal aggregate. Moreover, the pore structure of the allophane aggregates at nanoscale favors the pesticide retention. The fractal and tortuous aggregates of nanoparticles play the role of nanolabyrinths. It is suggested that chlordecone storage in allophanic soils could be the result of the low transport properties (permeability and diffusion) in the allophane aggregates. The poor accessibility to the pesticide trapped in the mesopore of allophane aggregates could explain the lower pollutant release in the environment. (Résumé d'auteur)
Mostrar más [+] Menos [-]Impacts of land uses on mercury retention in long-time cultivated soils, Brazilian Amazon
2013
Comte I. | Lucotte M. | Davidson R. | Reis de Carvalho C. | de Assis Oliveira F. | Rousseau G.X.
Many studies have shown the relationship between fire clearing and mercury contamination of aquatic ecosystems in the Brazilian Amazon. This study aimed at quantifying mercury content in long-time cultivated soils and at assessing the potential of a fire-free alternative clearing technique on mercury retention for long-time cultivated soils compared to traditional slash-and-burn. This case study included five land uses: one crop plot and one pasture plot cleared using slash-and-burn, one crop plot and one pasture plot cleared using chop-and-mulch, and one 40-year-old forest as a control. Low mercury concentrations were recorded in the surface horizon (24.83 to 49.48 ng g?1, 0–5 cm depth). The long-time cultivation (repeated burnings) of these soils triggered large mercury losses in the surface horizon, highlighted by high enrichment factors from surface to deeper horizons. The predominant effect of repeated burnings before the experimental implementation did not let us to distinguish a positive effect of the chop-and-mulch clearing method on soil mercury retention for crops and pastures. Moreover, some processes related to the presence of the mulch may favor mercury retention (Hg volatilization decrease, cationic sites increase), while others may contribute to mercury losses (cationic competition and dislocation, mobilization by the dissolved organic matter). (Résumé d'auteur)
Mostrar más [+] Menos [-]Diagnosis and management of field pollution in the case of an organochlorine pesticide, the chlordecone
2014
Woignier T. | Clostre F. | Cattan P. | Levillain J. | Cabidoche Y.M. | Lesueur Jannoyer M.
Physico-chemical and microbiological characteristics of agricultural soil of groundwater source of city Velika Plana [Serbia] - Livade
2006
Brebanovic, B. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Sikiric, B. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Perovic, V. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Zdravkovic-Boreli, Dj. (Institut za vodoprivredu Jaroslav Cerni, Beograd (Serbia))
In the frame of the project Water Supplying of the Cities and Protection of the Groundwater Quality in the Velika Morava Valley, was obtained the analysis of potential polluters of groundwater sources of town Velika Plana - Livade. This paper presents results of water physical, chemical and microbiological characteristics of soil. According to the results of research and way of usage of the soil, it was concluded that agricultural production does not have negative influence on quality of the groundwater source.
Mostrar más [+] Menos [-]Conditions of physico-chemical and microbiological characteristics of agricultural soil of groundwater source of city Smederevska Palanka - Trnovce [Serbia]
2006
Pivic, R. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Rasulic, N. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Nikolovski, M. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu | Popovic, V. (Institut za zemljiste, Beograd (Serbia)), E-mail: soilscis@eunet.yu
In the frame of the project Water Supplying of the Cities and Protection of the Groundwater Quality in the Velika Morava Valley, was obtained the analysis of potential polluters of groundwater source of city Smederevska Palanka - Trnovce. This paper presents results of water physical, chemical and microbiological characteristics of soil. According to the results of research and way of usage of the soil, it was concluded that agricultural production does not have negative influence on quality of the groundwater source.
Mostrar más [+] Menos [-]