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Resultados 1781-1790 de 62,508
Has the environmental movement help or hindered?.
1977
Delanay L.
Agricultural return flows, and fish and wildlife resources: In the Imperial Valley they interact ironically [Irrigation, California].
1977
Herrgesell P.L.
Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.) Texto completo
2015
Rothenberg, Sarah E. | Mgutshini, Nomathamsanqa L. | Bizimis, Michael | Johnson-Beebout, Sarah E. | Ramanantsoanirina, Alain
Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.) Texto completo
2015
Rothenberg, Sarah E. | Mgutshini, Nomathamsanqa L. | Bizimis, Michael | Johnson-Beebout, Sarah E. | Ramanantsoanirina, Alain
Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.) Texto completo
2015
Rothenberg, Sarah E. | Mgutshini, Nomathamsanqa L. | Bizimis, Michael | Johnson-Beebout, Sarah E. | Ramanantsoanirina, Alain
The rice ingestion rate in Madagascar is among the highest globally; however studies concerning metal(loid) concentrations in Madagascar rice are lacking. For Madagascar unpolished rice (n = 51 landraces), levels of toxic elements (e.g., total mercury, methylmercury, arsenic and cadmium) as well as essential micronutrients (e.g., zinc and selenium) were uniformly low, indicating potentially both positive and negative health effects. Aside from manganese (Wilcoxon rank sum, p < 0.01), no significant differences in concentrations for all trace elements were observed between rice with red bran (n = 20) and brown bran (n = 31) (Wilcoxon rank sum, p = 0.06–0.91). Compared to all elements in rice, rubidium (i.e., tracer for phloem transport) was most positively correlated with methylmercury (Pearson's r = 0.33, p < 0.05) and total mercury (r = 0.44, p < 0.05), while strontium (i.e., tracer for xylem transport) was least correlated with total mercury and methylmercury (r < 0.01 for both), suggesting inorganic mercury and methylmercury were possibly more mobile in phloem compared to xylem.
Mostrar más [+] Menos [-]Soil thresholds and a decision tool to manage food safety of crops grown in chlordecone polluted soil in the French West Indies Texto completo
2017
Clostre F. | Letourmy P. | Lesueur Jannoyer M.
Due to the persistent pollution of soils by an organochlorine, chlordecone (CLD also known as Kepone ©) in the French West Indies, some crops may be contaminated beyond the European regulatory threshold, the maximum residue limit (MRL). Farmers need to be able to foresee the risk of not complying with the regulatory threshold in each field and for each crop, if not, farmers whose fields are contaminated would have to stop cultivating certain crops in the fields concerned. To help farmers make the right choices, we studied the relationship between contamination of the soil and contamination of crops. We showed that contamination of a crop by CLD depended on the crop concerned, the soil CLD content and the type of soil. We grouped crop products in three categories: (i) non-uptakers and low-uptakers, (ii) medium-uptakers, and (iii) high-uptakers, according to their level of contamination and the resulting risk of exceeding MRL. Using a simulation model, we computed the soil threshold required to ensure the risk of not complying with MRL was sufficiently low for each crop product and soil type. Threshold values ranged from 0.02 ?gkg?1 for dasheen grown in nitisol to 1.7 ?gkg?1 for yam grown in andosol in the high-uptake category, and from 1 ?gkg?1 for lettuce grown in nitisol to 45 ?gkg?1 for the leaves of spring onions grown in andosol in the medium-uptake category. Contamination of non-uptakers and low-uptakers did not depend on soil contamination. With these results, we built an easy-to-use decision support tool based on two soil thresholds (0.1 and 1 ?gkg?1) to enable growers to adapt their cropping system and hence to be able to continue farming. (Résumé d'auteur)tttttt
Mostrar más [+] Menos [-]Field surveys of vegetation during a period of rising electric power generation in the Ohio River Valley [Sulfur dioxide].
1984
Jacobson J.S. | Showman R.E.
Diesel exhaust odor and irritants: a review [Light-duty vehicles, air pollution].
1983
Cernansky N.P.
Factors affecting the variability of summertime sulfate in a rural area using principal component analysis [Air pollution].
1982
Lioy P.J. | Mallon R.P. | Lippmann M. | Knelp T.J. | Samson P.J.
Estimation of economic losses to the agricultural sector form airborne residuals in the Ohio River basin region [USA].
1982
Page W.P. | Arbogast G. | Fabian R.G. | Ciecka J.
Silver Valley lead study: further analysis of the relationship between blood lead and air lead [Air pollution].
1982
Snee R.D.
Permitting a wood-burning boiler in a major metropolitan area [Staten Island, NY].
1982
Foster K.L. | Scherr R.C. | Dickson R.E.