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971.
Stéphanie Topoliantz Jean-François Ponge Dominique Arrouays Sylvain Ballof Patrick Lavelle 《Biology and Fertility of Soils》2002,36(4):313-319
A biofertilisation assay was conducted in Maripasoula (French Guiana), testing the effects of three different organic amendments (manioc peels, sawdust and wood charcoal) and the inoculation of the endogeic earthworm Pontoscolex corethrurus on pod production of Vigna unguiculata sesquipedalis and on soil chemical properties (pH, C, N, total and exchangeable P and K). Pod production was highest with manioc peels as available P increased in the soil. Wood charcoal also had a beneficial effect on pod production as it decreased acidity and increased the C:N ratio in the soil. In sawdust-amended soil, pod production did not differ from that in unamended soil. Inoculation of earthworms at a density of 80 sub-adults m-2 did not significantly affect either pod production or soil nutrient content directly, although it increased the positive effect of manioc peels on pod production. Soil nutrient content, pod production and earthworm density at the end of the experiment were negatively correlated with soil moisture and positively with each other. Despite the strong effect of moisture, this assay demonstrated an interaction between the earthworm P. corethrurus and the legume V. unguiculata sesquipedalis mediated by soil nutrient content and organic matter inputs. We conclude that manioc peels improved soil P availability and were an interesting amendment for legume crops. We discuss also the effect of earthworm inoculation. 相似文献
972.
Carmen G. Méndez-García Mayra Y. Luna-Porres Maria E. Montero-Cabrera Marusia Renteria-Villalobos Bernardo Pérez-Cázares Rafael García-Tenorio 《Journal of Soils and Sediments》2016,16(7):1970-1985
Purpose
The El Granero reservoir is the last reservoir of the Rio Conchos before it joins the Rio Grande at the Mexico–USA border. This reservoir, together with the San Marcos reservoir, is located in the arid region of Chihuahua, Mexico. High, naturally occurring radioactivity levels, as well as high arsenic (As) concentrations, have been found in both reservoirs. The main goal of this research was to establish the spatial and temporal distribution of trace and radioactive elements in surface sediments and cores collected from these reservoirs.Materials and methods
Sediment cores were dated using 210Pb and 137Cs measurements and applying the constant rate of supply (CRS) model. Major, trace, and radioactive elements were determined in surface samples and three sediment cores. Radioactive elements were determined by both alpha and gamma spectrometry. Major and trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) using the EPA 3051a method. Enrichment factors (EF), contamination factors (CF), and pollution load indexes (PLI) were calculated in order to identify the human impact in both reservoirs, whereas the chemical index weathering (CIW) was used to assess differences in the degree of weathering.Results and discussion
High uranium (U) enrichment (EFs?=?24.9–54.7) was observed in core layers at the San Marcos reservoir, while in surface sediments, this enrichment was lower. The high variability of lead (Pb) and As in sediment cores from the Granero reservoir was attributed to human influence. Arsenic and Pb enrichment differences between entry and exit sediment cores were explained by the filtering capabilities of the elongated shape, the topography, and the presence of plants on the reservoir’s bed. The highest PLI was found at the entrance core of the Granero reservoir.Conclusions
The natural element concentration levels of As, Pb, and U were established at the Granero reservoir. High EFs for As and Pb suggest an anthropogenic origin of these pollutants at specific time intervals. High U concentrations in the San Marcos area are explained as naturally occurring. The concentrations of As in most of the studied sediments could pose a risk to human health by As ingestion, since they are above the probable effect level (PEL).973.
Falilou Diallo Dominique Masse Karamoko Diarra Frédéric Feder 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):215-223
ABSTRACTThe productivity levels of two arenosol (Ar40) and fluvisol (FL40) fields that had been cultivated for over 40 years were compared to that of fields with the same soils located nearby but never previously cultivated, i.e. Ar0 and FL0, respectively. Application of poultry manure (PM) and sewage sludge (SS) were compared to a mineral fertilizer (T100), corresponding to 100 kg/ha of nitrogen, over three lettuce (Lactuca sativa L.) crop cycles. PM and SS were applied at 50 and 150 kg/ha nitrogen equivalent fertilizer doses. Biomass production levels in the organic and mineral treatments were similar, except for the SS-50 for FL0 and the PM-150 for Ar40, FL40 and FL0. Biomass production levels of Ar40 were higher than those of Ar0 for the first cycle. In the initial state, the soil P content in Ar40 was higher than that of the Ar0 soil. With the treatment repetition, Ar0 showed the same production level as Ar40. For the fluvisols, biomass production levels of FL40 were lower than those of FL0 for the first cycle. Indeed, the initial nitrate content in FL40 was lower than in FL0. The biomass production levels of FL40 were higher than those of FL0 for the following cycles. 相似文献
974.
J. Zayed P. André J. C. Panisset S. Ducic G. Campanella M. Roy G. Kennedy C. Delisle 《Water, air, and soil pollution》1990,49(1-2):197-203
Parkinson's disease (PD) has been proposed to result from the interaction of aging and environment in susceptible individuals. The prevalence of PD in Quebec was 84 per 100 000 in 1985. The regional variation observed has been linked with several environmental factors. We intended to verify the existence of a relation between the development of PD with exposure to 3 metal pollutants: Fe, Mn, and Al. The choice of these metals rests on their potential presence in the environment caused by the industrial activity in the region studied, and on the fact that it theoretically favors the prevalence of the illness. Environmental exposure to these metals and the resulting risks were evaluated using red spruce as a bio-indicator. The metal concentrations in tree rings were determined by neutron activation analysis. These concentrations permitted a temporal estimation of contamination in each of the territories studied, from 1938 to 1987. The risk of environmental exposure was assumed to be proportional to the concentration of the metal. The calculated risks combined with the history of residence allowed a comparison between parkinsonians and controls. It appeared that environmental exposure to the metals was not significantly different between those two groups. 相似文献
975.
Fermentation of white wines in the presence of wood chips of American and French oak 总被引:2,自引:0,他引:2
Pérez-Coello MS Sánchez MA García E González-Viñas MA Sanz J Cabezudo MD 《Journal of agricultural and food chemistry》2000,48(3):885-889
Must obtained from Airén grapes was fermented in the presence of wood chips (4 and 7 g/L) of either French oak (from Vosges, central France, and Allier zones) or American oak. Fermentation yields were higher than in the control fermentations carried out in the absence of wood, and production of volatile substances during fermentation (alcohols, esters, and acetates) was also higher. The volatile substances that leached out of the wood were analyzed by GC-MS-SIR. The results showed that their concentrations depended on the type and amount of the oak; some of these substances were consumed in part by the yeasts during fermentation. A taste panel favorably assessed the wines produced by fermentation in the presence of oak chips, which retained part of the must original fruity aroma. 相似文献
976.
María Ferriol Maria Belén Picó Fernando Nuez 《Genetic Resources and Crop Evolution》2003,50(3):227-238
Increasing the knowledge of the molecular diversity of a crop is essential for extending its genetic base, identifying cultivars and selecting parental varieties for breeding programs. In this sense, Cucurbita maxima Duch. is poorly characterised. Nineteen accessions of this species and 8 related Cucurbita accessions were included in a genetic diversity analysis. For this purpose, Random Amplified Polymorphic DNA markers (RAPDs), which analyse neutral variability, and Sequence-Based Amplified Polymorphism (SBAPs), which preferentially amplify coding regions of the genome, were used. While the UPGMA cluster and the principal coordinates analysis obtained using RAPDs did not group the different accessions according either to fruit morphological criteria or to passport data (origin and agro-climatic conditions), the principal coordinates analysis obtained using SBAPs grouped the different pumpkin accessions fundamentally according to the type of use (human consumption, animal fodder or ornamental). This passport trait is reported to be associated with agronomic breeding characters of interest. The usefulness of both types of markers for discriminating accessions of breeding interest is discussed. 相似文献
977.
Grova N Feidt C Crépineau C Laurent C Lafargue PE Hachimi A Rychen G 《Journal of agricultural and food chemistry》2002,50(16):4640-4642
Polycyclic aromatic hydrocarbons (PAHs), mainly formed by incomplete anthropogenic organic matter combustion, are ubiquitous in the environment. To assess milk PAH contamination sources, milk samples were collected from the tank milk at farms located near potential contaminating emission sources such as cementworks, steelworks, and motorways. PAH analyses were carried out by gas chromatography coupled to mass spectrometry. Eight PAHs were identified in milk: naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, fluoranthene, pyrene, and benzo[a]anthracene. For all potential contaminating sources, these eight PAHs were detected with similar profiles and at low concentrations except for fluorene and naphthalene, for which source-molecule interaction is pointed out. 相似文献
978.
Houessou JK Benac C Delteil C Camel V 《Journal of agricultural and food chemistry》2005,53(4):871-879
The presence of polycyclic aromatic hydrocarbons (PAHs) in coffee has been reported and is suspected to be due to the degradation of coffee compounds during the roasting step. Due to the high toxicity of these compounds, among which benzo[a]pyrene is known to be the most carcinogenic, their presence in the coffee, especially the coffee brew that is directly ingested by the consumer, is of prime importance. However, due to the low solubility of these compounds, their concentrations are expected to be rather low. As a consequence, reliable and sensitive analytical methods are required. The aim of this study was to develop a reliable and fast analytical procedure to determine these organic micropollutants in coffee brew samples. PAHs were retained on a 0.5 g polystyrene-divinylbenzene cartridge before being eluted by a mixture of methanol/tetrahydrofuran (10:90 v/v), concentrated, and directly analyzed by reversed-phase high-performance liquid chromatography coupled to a fluorescence detector. Application to the determination of PAHs in several coffee brew samples is also given, with mean estimated concentrations in the range of 0-100 ng L(-1) for suspected benzo[b]fluoranthene and benzo[a]pyrene, whereas no fluoranthene could be detected. Tentative identification was made on the basis of UV spectra. However, identification of the suspected traces of PAHs could not be achieved due to matrix effects, so that the presence of coeluting compounds may not be excluded. 相似文献
979.
Improvement of table grapes quality and safety by the combination of modified atmosphere packaging (MAP) and eugenol, menthol, or thymol 总被引:1,自引:0,他引:1
Valverde JM Guillén F Martínez-Romero D Castillo S Serrano M Valero D 《Journal of agricultural and food chemistry》2005,53(19):7458-7464
Table grape is a nonclimacteric fruit that shows a rapid loss of quality during storage and is very susceptible to colonization by fungi, especially Botrytis cinerea, which is considered the most important disease of this commodity. To solve this problem, synthetic fungicides have been used, although legal restrictions and consumer's concern demand the search of other safe means. In the present paper, and as an alternative of synthetic fungicides, an active packaging to improve MAP effectiveness on preserving table grape (cv. Crimson Seedless) quality and safety was developed by the addition of 0.5 mL of eugenol, thymol, or menthol inside the packages. Packages were stored at 1 degree C for 35 days. The final gas composition inside the packages was 1.4-2.0 and 10.0-14.5 kPa of CO(2) and O(2), respectively, with no significant slight differences among treatments. Results showed that the addition of eugenol, thymol, or menthol improved the beneficial effect of MAP in terms of delaying weight loss and color changes, retarding degrees Brix/acidity ratio evolution, and maintaining of firmness. Thereafter, these treatments showed additional benefit in terms of delayed rates of rachis deterioration and berry decay. Finally, the total viable counts for both mesophilic aerobics and especially yeast and molds were significantly reduced in the grapes packaged with the natural antimicrobial compounds. All of the above effects led to maintenance of table grape quality and safety for longer storage periods (3 additional weeks as compared to controls under MAP only). 相似文献
980.
Chemical composition and antifungal activity of essential oil of Chrysactinia mexicana gray 总被引:1,自引:0,他引:1
Cárdenas-Ortega NC Zavala-Sánchez MA Aguirre-Rivera JR Pérez-González C Pérez-Gutiérrez S 《Journal of agricultural and food chemistry》2005,53(11):4347-4349
The chemical composition of the essential oil of Chysactinia mexicana was analyzed by gas chromatography-mass spectrometry. Seventeen compounds were characterized; eucalyptol (41.3%), piperitone (37.7%), and linalyl acetate (9.1%) were found as the major components. The essential oil of leaves and piperitone completely inhibited Aspergillus flavus growth at relatively low concentrations (1.25 and 0.6 mg/mL, respectively). 相似文献