排序方式: 共有70条查询结果,搜索用时 15 毫秒
41.
Comparative bioaccumulation kinetics of trace elements in Mediterranean marine sponges 总被引:1,自引:0,他引:1
Genta-Jouve G Cachet N Oberhänsli F Noyer C Teyssié JL Thomas OP Lacoue-Labarthe T 《Chemosphere》2012,89(3):340-349
While marine organisms such as bivalves, seagrasses and macroalgae are commonly used as biomonitors for the environment pollution assessment, widely distributed sponges received little attention as potential helpful species for monitoring programmes. In this study, the trace element and radionuclide bioaccumulation and retention capacities of some marine sponges were estimated in a species-comparative study using radiotracers technique. Six Mediterranean species were exposed to background dissolved concentrations of 110mAg, 241Am, 109Cd, 60Co, 134Cs, 54Mn, 75Se and 65Zn allowing the assessment of the uptake and depuration kinetics for selected elements. Globally, massive demosponges Agelas oroides, Chondrosia reniformis and Ircinia variabilis displayed higher concentration factor (CF) than the erectile ones (Acanthella acuta, Cymbaxinella damicornis, Cymbaxinella verrucosa) at the end of exposure, suggesting that the morphology is a key factor in the metal bioaccumulation efficiency. Considering this observation, two exceptions were noted: (1) A. acuta reached the highest CF for 110mAg and strongly retained the accumulated metal without significant Ag loss when placed in depuration conditions and (2) C. reniformis did not accumulate Se as much as A. oroides and I. variabilis. These results suggest that peculiar metal uptake properties in sponges could be driven by specific metabolites or contrasting biosilification processes between species, respectively. This study demonstrated that sponges could be considered as valuable candidate for biomonitoring metal contamination but also that there is a need to experimentally highlight metal-dependant characteristic among species. 相似文献
42.
Plants grown on sewage sludge in South China and its relevance to sludge stabilization and metal removal 总被引:12,自引:0,他引:12
The production of sewage sludge in China has been increasing sharply in order to treat 40% of the municipal sewage in 2005 as planned by central government. The main sludge disposal method is landfill owing to heavy metal contamination, but it presents an attractive potential for agricultural land application. Experiments were carried out to study the simultaneous metal removal and sludge stabilization byplants. The sludge samples were collected from Datansha Wastewater Treatment Plant of Guangzhou, it contained excessive Cu and Zn comparedwith the Chinese National Standard for Agricultural Use of Sewage Sludge. Plants growing on sludge beds were investigated to follow their growthand metal uptake. 30 sludge plants were identified during 1 year‘s observation. A Zn high-accumulating and high growth rate plant( A/ocas/amacrorrhiza) was selected and grown on sludge beds in plots. The water, organic matter, heavy metals and nutrients contents, the E. colinumber and the cress seed germination index were monitored for the slu,ge samples collected monthly. The plant growth pparameters and its heavy metals contents were also determined. The sewage sludge treated by plants could be stabilized at about 5 months, the E. coli numberwas significantly decreased and the cress seed germination index attained 100%. Crop on sludge could ameliorate the sludge drying. Theexperiments are continuing to find out the appropriate plant combination for simultaneous sludge stabilization and metal removal for an acceptableperiod. Comparisons between the proposed processes and other methods for treating produced sludge such as composting, chemical and bacterial. 相似文献
43.
Dromard Charlotte R. Allenou Jean-Pierre Tapie Nathalie Budzinski Hélène Cimmaterra Nicolas De Rock Pauline Arkam Salim Cordonnier Sébastien Gonzalez Jean-Louis Bouchon-Navaro Yolande Bouchon Claude Thouard Emmanuel 《Environmental science and pollution research international》2022,29(54):81546-81556
Environmental Science and Pollution Research - The present study, conducted in the Galion Bay in Martinique, aims to highlight the temporal and seasonal variations of chlordecone contamination (an... 相似文献
44.
45.
Hanxiang Wu Sophie Marhadour Zhi-Wei Lei Wen Yang Cécile Marivingt-Mounir Jean-Louis Bonnemain Jean-François Chollet 《Environmental science and pollution research international》2018,25(15):14336-14349
Producing quality food in sufficient quantity while using less agrochemical inputs will be one of the great challenges of the twenty-first century. One way of achieving this goal is to greatly reduce the doses of plant protection compounds by improving the targeting of pests to eradicate. Therefore, we developed a vectorization strategy to confer phloem mobility to fenpiclonil, a contact fungicide from the phenylpyrrole family used as a model molecule. It consists in coupling the antifungal compound to an amino acid or a sugar, so that the resulting conjugates are handled by active nutrient transport systems. The method of click chemistry was used to synthesize three conjugates combining fenpiclonil to glucose or glutamic acid with a spacer containing a triazole ring. Systemicity tests with the Ricinus model have shown that the amino acid promoiety was clearly more favorable to phloem mobility than that of glucose. In addition, the transport of the amino acid conjugate is carrier mediated since the derivative of the L series was about five times more concentrated in the phloem sap than its counterpart of the D series. The systemicity of the L-derivative is pH dependent and almost completely inhibited by the protonophore carbonyl cyanide 3-chlorophenylhydrazone (CCCP). These data suggest that the phloem transport of the L-derivative is governed by a stereospecific amino acid carrier system energized by the proton motive force. 相似文献
46.
47.
48.
Yang Q Benoy GA Chow TL Daigle JL Bourque CP Meng FR 《Journal of environmental quality》2012,41(1):64-72
Runoff from crop production in agricultural watersheds can cause widespread soil loss and degradation of surface water quality. Beneficial management practices (BMPs) for soil conservation are often implemented as remedial measures because BMPs can reduce soil erosion and improve water quality. However, the efficacy of BMPs may be unknown because it can be affected by many factors, such as farming practices, land-use, soil type, topography, and climatic conditions. As such, it is difficult to estimate the impacts of BMPs on water quality through field experiments alone. In this research, the Soil and Water Assessment Tool was used to estimate achievable performance targets of water quality indicators (sediment and soluble P loadings) after implementation of combinations of selected BMPs in the Black Brook Watershed in northwestern New Brunswick, Canada. Four commonly used BMPs (flow diversion terraces [FDTs], fertilizer reductions, tillage methods, and crop rotations), were considered individually and in different combinations. At the watershed level, the best achievable sediment loading was 1.9 t ha(-1) yr(-1) (89% reduction compared with default scenario), with a BMP combination of crop rotation, FDT, and no-till. The best achievable soluble P loading was 0.5 kg ha(-1) yr(-1) (62% reduction), with a BMP combination of crop rotation and FDT and fertilizer reduction. Targets estimated through nonpoint source water quality modeling can be used to evaluate BMP implementation initiatives and provide milestones for the rehabilitation of streams and rivers in agricultural regions. 相似文献
49.
Saison C Perrin-Ganier C Schiavon M Morel JL 《Environmental pollution (Barking, Essex : 1987)》2004,130(2):275-285
This study examined the effect of regular tillage and cropping on the dissipation rate of PAHs in contaminated soil. Lysimeters were placed under natural climatic conditions for 2 years and designed to measure the concentration of PAHs in soil and leachates and their toxicity. The soil initially contained 2077 microg PAHs g(-1). The largest decrease in PAHs concentration occurred during the first 6 months. No further significant decrease was observed after this time. The surface soil layer always contained significantly less PAHs than the deeper layer, regardless of the treatments. Less than 8.4 x 10(-8)% of the PAH initially present in the soil (e.g. less or equal to 33 microg PAHs per lysimeter) were leached from the soils during the experiment and the leachates presented no toxicity (as measured by the Microtox test). The toxicity of the soils decreased with time and was significantly lower on the cropped soil compared to the other treatments, despite the residual concentration of PAHs being the highest in this soil. This study demonstrated that the dissipation rates of PAHs were slow after using natural attenuation even when tillage and cropping were performed at the soil surface. 相似文献
50.
Julio César Marín Leal Stanislas Dubois Francis Orvain Robert Galois Jean-Louis Blin Michel Ropert Marie-Paule Bataillé Alain Ourry Sébastien Lefebvre 《Marine Biology》2008,153(4):673-688
Food sources for cultivated marine bivalves generally are not well identified, although they are essential for a better understanding
of coastal ecosystems and for the sustainability of shellfish farming activities. In addition to phytoplankton, other organic
matter sources (OMS), such as microphytobenthos and detritus (of terrestrial or marine origins), can contribute significantly
to the growth of marine bivalves. The aim of this study was to identify the potential food sources and to estimate their contributions
to the growth of the Pacific oyster (Crassostrea gigas) in two contrasting trophic environments of Normandy (France): the Baie des Veys (BDV) and the Lingreville area (LIN). Two
sites were studied in the BDV area (BDV-S and BDV-N) and one in the LIN area. To estimate the contribution of each type of
OMS, we used a combination of stable natural isotope composition (δ13C, δ15N) analysis of OMS and oyster tissue together with a modelling exercise. Field sampling was conducted every 2 months over
1 year. The sampled sources were suspended particulate organic matter from marine (PhyOM) and terrestrial (TOM) origins, microphytobenthos
(MPB), detrital organic matter from the superficial sediment (SOM), and macroalgae (Ulva sp., ULV). A statistical mixing model coupled to a bioenergetic model was used to calculate the contributions of each different
source at different seasons. Results showed that isotopic composition of the animal flesh varied with respect to the potential
OMS over the year within each ecosystem. Significant differences were also observed among the three locations. For instance,
the δ13C and δ15N values of the oysters ranged from −20.0 to −19.1‰ and from 6.9 to 10.8‰ at BDV-S, from −19.4 to −18.1‰ and from 6.4 to 10.0‰
at BDV-N, and from −21.8 to −19.4‰ and from 6.3 to 8.3‰ at LIN. The contributions of the different sources to oyster growth
differed depending on the ecosystem and on the period of the year. Phytoplankton (PhyOM) predominated as the principal food
source for oysters (particularly in the LIN location). MPB, TOM, and ULV detritus also possibly contributed to oysters’ diet
during summer and autumn at the BDV-S and BDV-N sites. SOM was not considered an OMS because it was already a mix of the other
four OMS, but rather a trophic reservoir that potentially mirrored the trophic functioning of marine ecosystems. 相似文献