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Results 1781-1790 of 62,157
Impacts of climate and management on water balance and nitrogen leaching from montane grassland soils of S-Germany
2017
Jin Fu | Gasche, Rainer | Na Wang | Haiyan Lu | Butterbach-Bahl, Klaus | Kiese, Ralf
How to design land application systems for agricultural utilization of sewage sludge [as a soil amendment].
1979
Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.)
2015
Rothenberg, Sarah E. | Mgutshini, Nomathamsanqa L. | Bizimis, Michael | Johnson-Beebout, Sarah E. | Ramanantsoanirina, Alain
Soil thresholds and a decision tool to manage food safety of crops grown in chlordecone polluted soil in the French West Indies
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
Show more [+] Less [-]Persistence of detectable insecticidal proteins from #Bacillus thuringiensis# (Cry) and toxicity after adsorption on contrasting soils
2016
Hung T.P. | Truong L.V. | Binh N.D. | Frutos R. | Quiquampoix H. | Staunton S.
Insecticidal Cry, or Bt, proteins are produced by the soil-endemic bacterium, Bacillus thuringiensis and some genetically modified crops. Their environmental fate depends on interactions with soil. Little is known about the toxicity of adsorbed proteins and the change in toxicity over time. We incubated Cry1Ac and Cry2A in contrasting soils subjected to different treatments to inhibit microbial activity. The toxin was chemically extracted and immunoassayed. Manduca sexta was the target insect for biotests. Extractable toxin decreased during incubation for up to four weeks. Toxicity of Cry1Ac was maintained in the adsorbed state, but lost after 2 weeks incubation at 25 °C. The decline in extractable protein and toxicity were much slower at 4 °C with no significant effect of soil sterilization. The major driving force for decline may be time-dependent fixation of adsorbed protein, leading to a decrease in the extraction yield in vitro, paralleled by decreasing solubilisation in the larval gut. (Résumé d'auteur)
Show more [+] Less [-]Investigating filamentous slime growth downstream of a municipal discharge [Sacramento River, California].
1978
Salo J.E. | Ikesaki T.
A review of recent reports dealing with the greenhouse effect of atmospheric carbon dioxide.
1984
Idso S.B.
Assessing impacts of ozone on agricultural crops. II. Crop yield functions and alternative exposure statistics [Barley, beans, cotton, peanuts, sorghum, soybeans, tomato, wheat].
1984
Heck W.W. | Cure W.W. | Rawlings J.O. | Zaragoza L.J. | Heagle A.S. | Heggestad H.E. | Kohut R.J. | Kress L.W. | Temple P.J.
Using farmers' actions to measure crop loss due to air pollution [Ozone, Illinois].
1984
Mjelde J.W. | Adams R.M. | Dixon B.L. | Garcia P.
Assessing impacts of ozone on agricultural crops. I. Overview.
1984
Heck W.W. | Cure W.W. | Rawlings J.O. | Zaragoza L.J. | Heagle A.S. | Heggestad H.E. | Kohut R.J. | Kress L.W. | Temple P.J.
