Sequential Application of Soil Vapor Extraction and Bioremediation Processes for the Remediation of Ethylbenzene-Contaminated Soils     

António Alves Soares  Maria Teresa Pinho  José Tomás Albergaria  Valentina Domingues  Maria da Concei??o M. Alvim-Ferraz  Paolo De Marco  Cristina Delerue-Matos 《Water, air, and soil pollution》2012,223(5):2601-2609

Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application of these technologies is presented as a valid option but is not yet entirely studied. This work presents the study of the remediation of ethylbenzene (EB)-contaminated soils, with different soil water and natural organic matter (NOMC) contents, using sequential SVE and BR. The obtained results allow the conclusion that: (1) SVE was sufficient to reach the cleanup goals in 63% of the experiments (all the soils with NOMC below 4%), (2) higher NOMCs led to longer SVE remediation times, (3) BR showed to be a possible and cost-effective option when EB concentrations were lower than 335?mg?kg _soil ^?1 , and (4) concentrations of EB above 438?mg?kg _soil ^?1 showed to be inhibitory for microbial activity.  相似文献   

Fast field cycling NMR relaxometry characterization of biochars obtained from an industrial thermochemical process   总被引：1，自引：0，他引：1  

Claudio De Pasquale  Valentina Marsala  Anne E. Berns  Massimo Valagussa  Alessandro Pozzi  Giuseppe Alonzo  Pellegrino Conte 《Journal of Soils and Sediments》2012,12(8):1211-1221

Purpose

Biochar has unique properties which make it a powerful tool to increase soil fertility and to contribute to the decrease of the amount of atmospheric carbon dioxide through the mechanisms of C sequestration in soils. Chemical and physical biochar characteristics depend upon the technique used for its production and the biomass nature. For this reason, biochar characterization is very important in order to address its use either for agricultural or environmental purposes.

Materials and methods

Three different biochars obtained from an industrial gasification process were selected in order to establish their chemical and physical peculiarities for a possible use in agronomical practices. They were obtained by charring residues from the wine-making industry (marc) and from poplar and conifer forests. Routine analyses such as pH measurements, elemental composition, and ash and metal contents were performed together with the evaluation of the cross-polarization magic angle spinning (CPMAS) ¹³C NMR spectra of all the biochar samples. Finally, relaxometry properties of water-saturated biochars were retrieved in order to obtain information on pore size distribution.

Results and discussion

All the biochars revealed basic pH values due to their large content of alkaline metals. The quality of CPMAS ¹³C NMR spectra, which showed the typical signal pattern for charred systems, was not affected by the presence of paramagnetic centers. Although paramagnetism was negligible for the acquisition of solid state spectra, it was effective in some of the relaxometry experiments. For this reason, no useful information could be retrieved about water dynamics in marc char. Conversely, both relaxograms and nuclear magnetic resonance dispersion profiles of poplar and conifer chars indicated that poplar char is richer in small-sized pores, while larger pores appear to be characteristic for the conifer char.

Conclusions

This study showed the potential of relaxometry in revealing chemical?Cphysical information on industrially produced biochar. This knowledge is of paramount importance to properly direct biochar agronomical uses.  相似文献   

Experimental cultivation of the Mediterranean calanoid copepods Temora stylifera and Centropages typicus in a pilot re‐circulating system     

Isabella Buttino  Adrianna Ianora  Silvia Buono  Valentina Vitiello  Maria G Malzone  Cira Rico  Antonio L Langellotti  Giovanni Sansone  Lorenzo Gennari  Antonio Miralto 《Aquaculture Research》2012,43(2):247-259

A pilot re‐circulating system was used for the cultivation of two Mediterranean calanoid copepods: Temora stylifera and Centropages typicus. The system automatically concentrated the naupliar and copepodite stages. Temora stylifera was fed the flagellate Rhodomonas baltica or Prorocentrum minimum, whereas C. typicus was fed with a mixture of R. baltica or P. minimum and Tetraselmis suecica. Both copepods also received Isochrysis galbana. After 21 days, the T. stylifera population increased 26‐fold, reaching a density of 38 000 individuals, mostly represented by nauplii (88%). The maximum density recorded was 380 ind. L^?1, with a production of 370 nauplii L^?1. On average, the egg hatching success for this copepod during the rearing period was 54%, with the highest viability in April and May (>75%). The C. typicus population increased more than 10‐fold after 7 weeks of rearing, reaching a density of 123 000 individuals, mainly represented by nauplii (>90%). The highest naupliar production was 100 ind. L^?1, with a mean egg hatching success of 68%. This system may be useful to produce nauplii and copepodite stages to be used as live, alternative or complementary food for fish larvae or to provide a ready source of organisms for physiological and bioassay studies.  相似文献   

Long-term erosion of tree reproductive trait diversity in edge-dominated Atlantic forest fragments     

Ariadna Valentina Lopes  Luciana Coe Girão  Carlos A. Peres 《Biological conservation》2009,142(6):1154-1997

Habitat loss and fragmentation promote relatively predicable shifts in the functional signature of tropical forest tree assemblages, but the full extent of cascading effects to biodiversity persistence remains poorly understood. Here we test the hypotheses that habitat fragmentation (a) alters the relative contribution of tree species exhibiting different reproductive traits; (b) reduces the diversity of pollination systems; and (c) facilitates the functional convergence of reproductive traits between edge-affected and early-secondary forest habitats (5-32 years old). This study was carried out in a severely fragmented 670-km² forest landscape of the Atlantic forest of northeastern Brazil. We assigned 35 categories of reproductive traits to 3552 trees (DBH ? 10 cm) belonging to 179 species, which described their pollination system, floral biology, and sexual system. Trait abundance was calculated for 55 plots of 0.1 ha across four habitats: forest edges, small forest fragments (3.4-83.6 ha), second-growth patches, and core tracts of forest interior within the largest available primary forest fragment (3500 ha) in the region. Edge-affected and secondary habitats showed a species-poor assemblage of trees exhibiting particular pollination systems, a reduced diversity of pollination systems, a higher abundance of reproductive traits associated with pollination by generalist diurnal vectors, and an elevated abundance of hermaphroditic trees. As expected, the reproductive signature of tree assemblages in forest edges and small fragments (edge-affected habitats), which was very similar to that of early second-growth patches, was greatly affected by both habitat type and plot distance to the nearest forest edge. In hyper-fragmented Atlantic forest landscapes, we predict that narrow forest corridors and small fragments will become increasingly dominated by edge-affected habitats that can no longer retain the full complement of tree life-history diversity and its attendant mutualists.  相似文献   

Metal Tolerance, Accumulation and Translocation in Poplar and Willow Clones Treated with Cadmium in Hydroponics   总被引：3，自引：0，他引：3  

Massimo Zacchini  Fabrizio Pietrini  Giuseppe Scarascia Mugnozza  Valentina Iori  Lucia Pietrosanti  Angelo Massacci 《Water, air, and soil pollution》2009,197(1-4):23-34

To evaluate the phytoremediation capability of some poplar and willow clones a hydroponic screening for cadmium tolerance, accumulation and translocation was performed. Rooted cuttings were exposed for 3 weeks to 50 μM cadmium sulphate in a growth chamber and morpho-physiological parameters and cadmium content distribution in various parts of the plant were evaluated. Total leaf area and root characteristics in clones and species were affected by cadmium treatment in different ways. Poplar clones showed a remarkable variability whereas willow clones were observed to be more homogeneous in cadmium accumulation and distribution. This behaviour was further confirmed by the calculation of the bio-concentration factor (BCF) and the translocation factor (Tf). Mean values of all the clones of the two Salicaceae species showed that willows had a far greater ability to tolerate cadmium than poplars, as indicated by the tolerance index (Ti), calculated on the dry weight of roots and shoots of plants. As far as the mean values of Tf was concerned, the capacity of willows to translocate was double that of poplars. On the contrary, the mean values of total BCF in poplar clones was far higher with respect to those in willows. The implications of these results in the selection of Salicaceae clones for phytoremediation purposes were discussed.  相似文献   

Monitoring deep Mediterranean rhodolith beds          下载免费PDF全文

Daniela Basso  Lorenza Babbini  Sara Kaleb  Valentina A. Bracchi  Annalisa Falace 《水产资源保护:海洋与淡水生态系统》2016,26(3):549-561

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Spatial scaling of wildland fuels for six forest and rangeland ecosystems of the northern Rocky Mountains, USA   总被引：1，自引：1，他引：0  

Robert E. Keane  Kathy Gray  Valentina Bacciu  Signe Leirfallom 《Landscape Ecology》2012,27(8):1213-1234

Wildland fuels are important to fire managers because they can be manipulated to achieve management goals, such as restoring ecosystems, decreasing fire intensity, minimizing plant mortality, and reducing erosion. However, it is difficult to accurately measure, describe, and map wildland fuels because of the great variability of wildland fuelbed properties over space and time. Few have quantified the scale of this variability across space to understand its effect on fire spread, burning intensity, and ecological effects. This study investigated the spatial variability of loading (biomass) across major surface and canopy fuel components in low elevation northern Rocky Mountain forest and rangeland ecosystems to determine the inherent scale of surface fuel and canopy fuel distributions. Biomass loadings (kg?m^?2) were measured for seven surface fuel components??four downed dead woody fuel size classes (0?C6?mm, 6?C25?mm, 25?C75?mm, and 75?+?mm), duff plus litter, shrub, and herb??using a spatially nested plot sampling design within a 1?km² square sampling grid installed at six sites in the northern US Rocky Mountains. Bulk density, biomass, and cover of the forest canopy were also measured for each plot in the grid. Surface fuel loadings were estimated using a combination of photoload and destructive collection methods at many distances within the grid. We quantified spatial variability of fuel component loading using spatial variograms, and found that each fuel component had its own inherent scale with fine fuels varying at scales of 1?C5?m, coarse fuels at 10?C150?m, and canopy fuels from 100 to 500?m. Using regression analyses, we computed a scaling factor of 4.6?m for fuel particle diameter (4.6?m increase in scale with each cm increase in particle diameter). Findings from this study can be used to design fuel sampling projects, classify fuelbeds, and map fuel characteristics, such as loading, to account for the inherent scale of fuel distributions to get more accurate fuel loading estimations.  相似文献   

Identification and Characterization of a Novel Lectin from the Clam Glycymeris yessoensis and Its Functional Characterization under Microbial Stimulation and Environmental Stress     

Tatyana O. Mizgina  Irina V. Chikalovets  Valentina I. Molchanova  Rustam H. Ziganshin  Oleg V. Chernikov 《Marine drugs》2021,19(9)

Lectin from the bivalve Glycymeris yessoensis (GYL) was purified by affinity chromatography on porcine stomach mucin–Sepharose. GYL is a dimeric protein with a molecular mass of 36 kDa, as established by SDS-PAGE and MALDI-TOF analysis, consisting of 18 kDa subunits linked by a disulfide bridge. According to circular dichroism data, GYL is a β/α-protein with the predominance of β-structure. GYL preferentially agglutinates enzyme-treated rabbit erythrocytes and recognizes glycoproteins containing O-glycosidically linked glycans, such as porcine stomach mucin (PSM), fetuin, thyroglobulin, and ovalbumin. The amino acid sequences of five segments of GYL were acquired via mass spectrometry. The sequences have no homology with other known lectins. GYL is Ca²⁺-dependent and stable over a range above a pH of 8 and temperatures up to 20 °C for 30 min. GYL is a pattern recognition receptor, as it binds common pathogen-associated molecular patterns, such as peptidoglycan, LPS, β-1,3-glucan and mannan. GYL possesses a broad microbial-binding spectrum, including Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli, Vibrio proteolyticus), but not the fungus Candida albicans. Expression levels of GYL in the hemolymph were significantly upregulated after bacterial challenge by V. proteolyticus plus environmental stress (diesel fuel). Results indicate that GYL is probably a new member of the C-type lectin family, and may be involved in the immune response of G. yessoensis to bacterial attack.  相似文献   

Improved physical control of glyphosate‐resistant Italian ryegrass (Lolium multiflorum) on rice paddy levees in Japan          下载免费PDF全文

Valentina Dwi Suci Handayani  Yuki Tanno  Masayuki Yamashita  Hiroyuki Tobina  Minoru Ichihara  Yoshiki Ishida  Hitoshi Sawada 《Weed Biology and Management》2017,17(2):77-83

Italian ryegrass ( Lolium multiflorum Lam.) is a non‐native annual winter grass that has seriously infested rice paddy levees and wheat fields in Japan. Recently, glyphosate‐resistant Italian ryegrass was found on paddy levees in central Japan, thereby making control of the grass by using glyphosate less effective. In this study, physical control methods were tested that combined the timing and frequency of mowing in order to more effectively control glyphosate‐resistant Italian ryegrass on rice paddy levees. A 3 year field experiment was conducted from 2012 to 2014 in a western region of Shizuoka Prefecture, where glyphosate‐resistant Italian ryegrass has become dominant. Five treatments were tested: (i) mowing once before the flowering of the grass (i.e. conventional mowing measure); (ii) mowing once during flowering; (iii) mowing twice during flowering; (iv) glyphosate application before flowering (i.e. one of the conventional mowing measures); and (v) no treatment. The above‐ground biomass, seed production, soil seed bank and seedling occurrence of Italian ryegrass were measured to determine the effectiveness of these treatments. Mowing during the flowering period resulted in reduced above‐ground biomass, seed production and soil seed bank when compared with the other treatments. Additionally, mowing twice during the flowering period resulted in a lower seedling density than mowing once. The results suggest that, in this region, physical control by mowing during the flowering period would be more effective than conventional measures for controlling glyphosate‐resistant Italian ryegrass.  相似文献   

The combined use of surgical debulking and diode laser photocoagulation for limbal melanoma treatment: a retrospective study of 21 dogs          下载免费PDF全文

Valentina Andreani  Adolfo Guandalini  Nunzio D'Anna  Chiara Giudice  Roberta Corvi  Nicola Di Girolamo  John S. Sapienza 《Veterinary ophthalmology》2017,20(2):147-154

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