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Effect of vinegar residue compost amendments on cucumber growth and Fusarium wilt 全文
2015
Du, Nanshan | Shi, Lu | Du, Lantian | Yuan, Yinghui | Li, Bin | Sang, Ting | Sun, Jin | Shu, Sheng | Guo, Shirong
Fusarium wilt of cucumber caused by Fusarium oxysporum f. sp. cucumerinum J. H. Owen is one of the major destructive soilborne diseases and results in considerable yield losses. Methyl bromide was once the most effective disease control method but has been confirmed as harmful to the environment. Using suppressive media as biological controls to assist crop growth is becoming popular. In this study, Fusarium wilt of cucumber was successfully controlled by a newly identified suppressive media: vinegar residue compost-amended media (vinegar residue compost mixed with peat and vermiculite in a 6:3:1 ratio (v/v) vinegar residue substrate (VRS). Greenhouse experiments were carried out to evaluate the effect of VRS on the growth of cucumber seedlings and disease suppression. The control was peat/vermiculite (2:1, v/v). To identify the mixed media most suitable for the growth of plants and their suppressiveness indicators, we evaluated the biological characteristics of cucumber, the physicochemical and biochemical properties of the growth media, and the enzyme activities. Total organic C (Cₒᵣg), microbial biomass C (Cₘᵢc), basal respiration (Rₘᵢc), and enzyme (catalase, invertase, urease, proteinase, phosphatase, β-glucosidase, and hydrolysis of fluorescein diacetate) activities increased significantly after vinegar waste compost amendment. The compost media also showed a significantly positive effect on the growth of cucumber seedlings and the suppression of the disease severity index (DSI, 38 % reduction). The cucumber rhizosphere population of F. oxysporum f. sp. cucumerinum (FOC) was significantly lower in VRS than in the control. These results demonstrate convincingly that vinegar residue compost-amended media has a beneficial effect on cucumber growth and could be applied as a method for biological control of cucumber Fusarium wilt.
显示更多 [+] 显示较少 [-]Effect of combined microbes on plant tolerance to Zn–Pb contaminations 全文
2015
Ogar, Anna | Sobczyk, Łukasz | Turnau, Katarzyna
The presence and composition of soil microbial communities has been shown to have a large impact on plant–plant interactions and consequently plant diversity and composition. The goal of the present study was to evaluate impact of arbuscular mycorrhizal fungi (AMF) and nitrogen-fixing bacteria, which constitutes an essential link between the soil and the plant’s roots. A greenhouse pot experiment was conducted to evaluate the feasibility of using selected microbes to improve Hieracium pilosella and Medicago sativa growth on Zn–Pb-rich site. Results of studies revealed that biomass, the dry mass of shoots and roots, increased significantly when plants were inoculated with mycorrhizal fungi and nitrogen-fixing bacteria. The addition of Azospirillum sp. and Nostoc edaphicum without mycorrhiza suppressed plant growth. Single bacterial inoculation alone does not have a positive effect on M. sativa growth, while co-inoculation with AMF improved plant growth. Plant vitality (expressed by the performance index) was improved by the addition of microbes. However, our results indicated that even dry heat sterilization of the substratum created imbalanced relationships between soil-plant and plants and associated microorganisms. The studies indicated that AMF and N₂-fixers can improve revegetation of heavy metal-rich industrial sites, if the selection of interacting symbionts is properly conducted.
显示更多 [+] 显示较少 [-]Metal bioaccumulation pattern by Cotylorhiza tuberculata (Cnidaria, Scyphozoa) in the Mar Menor coastal lagoon (SE Spain) 全文
2015
Muñoz-Vera, Ana | García, Gregorio | García-Sánchez, Antonio
Coastal lagoons are ecosystems highly vulnerable to human impacts because of their situation between terrestrial and marine environment. Mar Menor coastal lagoon is one of the largest lagoons of the Mediterranean Sea, placed in SE Spain and subjected to major human impacts, in particular the mining of metal sulphides. As a consequence, metal concentration in water column and sediments of this ecosystem is usually higher than in other areas. For monitoring ecosystem health, the present study has assessed the ability of Cotylorhiza tuberculata for bioaccumulating metals from sea water. Up to 65 individuals were sampled at 8 different sampling stations during the summer of 2012. Although the concentration values for different elements considered were moderate (Pb: 0.04-29.50 ppm, Zn: 2.27-93.44 ppm, Cd: 0-0.67 ppm, As: 0.56-130.31 ppm) by dry weight of the jellyfish tissues (bell and oral arms combined), bioconcentration levels in relation to seawater metal concentration were extremely high. In any case, the use or disposal of these organisms should consider their metal content because of their potential environmental and health implications.
显示更多 [+] 显示较少 [-]Evaluation of the fate of arsenic-contaminated groundwater at different aquifers of Thar coalfield Pakistan 全文
2015
Ali, Jamshed | Kazi, Tasneem G. | Baig, Jameel A. | Afridi, Hassan I. | Arain, Mariam S. | Ullah, Naeem | Brahman, Kapil D. | Arain, Sadaf S. | Panhwar, Abdul H.
In present study, the ground water at different aquifers was evaluated for physicochemical parameters, iron, total arsenic, total inorganic arsenic and arsenic species (arsenite and arsenate). The samples of groundwater were collected at different depths, first aquifer (AQ₁) 50–60 m, second aquifer (AQ₂) 100–120 m, and third aquifer (AQ₃) 200–250 m of Thar coalfield, Pakistan. Total inorganic arsenic was determined by solid phase extraction using titanium dioxide as an adsorbent. The arsenite was determined by cloud point extraction using ammonium pyrrolidinedithiocarbamate as a chelating reagent, and resulted complex was extracted by Triton X-114. The resulted data of groundwater were reported in terms of basic statistical parameters, principal component, and cluster analysis. The resulted data indicated that physicochemical parameters of groundwater of different aquifers were exceeded the World Health Organization provisional guideline for drinking water except pH and SO₄ ²⁻. The positive correlation was observed between arsenic species and physicochemical parameters of groundwater except F⁻ and K⁺, which might be caused by geochemical minerals. Results of cluster analysis indicated that groundwater samples of AQ₁ was highly contaminated with arsenic species as compared to AQ₂ and AQ₃ (p > 0.05).
显示更多 [+] 显示较少 [-]Simultaneous detection of imidacloprid and parathion by the dual-labeled time-resolved fluoroimmunoassay 全文
2015
Shi, Haiyan | Sheng, Enze | Feng, Lu | Zhou, Liangliang | Hua, Xiude | Wang, Minghua
A highly sensitive direct dual-labeled time-resolved fluoroimmunoassay (TRFIA) to detect parathion and imidacloprid simultaneously in food and environmental matrices was developed. Europium (Eu³⁺) and samarium (Sm³⁺) were used as fluorescent labels by coupling separately with L₁-Ab and A₁P₁-Ab. Under optimal assay conditions, the half-maximal inhibition concentration (IC₅₀) and limit of detection (LOD, IC₁₀) were 10.87 and 0.025 μg/L for parathion and 7.08 and 0.028 μg/L for imidacloprid, respectively. The cross-reactivities (CR) were negligible except for methyl-parathion (42.4 %) and imidaclothiz (103.4 %). The average recoveries of imidacloprid ranged from 78.9 to 104.2 % in water, soil, rice, tomato, and Chinese cabbage with a relative standard deviation (RSD) of 2.4 to 11.6 %, and those of parathion were from 81.5 to 110.9 % with the RSD of 3.2 to 10.5 %. The results of TRFIA for the authentic samples were validated by comparison with gas chromatography (GC) analyses, and satisfactory correlations (parathion: R ² = 0.9918; imidacloprid: R ² = 0.9908) were obtained. The results indicate that the dual-labeled TRFIA is convenient and reliable to detect parathion and imidacloprid simultaneously in food and environmental matrices.
显示更多 [+] 显示较少 [-]Histopathological changes in the perivisceral fat body of Rhinocricus padbergi (Diplopoda, Spirobolida) triggered by biosolids 全文
2015
Francisco, Annelise | Christofoletti, Cintya Aparecida | Neto, Nilton Righetto | Fontanetti, Carmem Silvia
Human activities generate a great amount of sewage daily, which is dumped into the sewer system. After sewage-treatment processes, sewage sludge is generated. Such byproduct can be treated by different methods; the result of treatment is a stabilized compost of reduced pathogenicity that has a similar inorganic chemical composition to the raw sewage sludge. After such pretreatment, sewage sludge is called a biosolids, and it can be used in agriculture. In this contest, the present study evaluated the effects of a sample of biosolids on the perivisceral fat body of a diplopod. These invertebrates are soil organisms that play an important role in the dynamics of terrestrial ecosystems, and as a consequence, they are in contact with xenobiotics present in this environmental compartment. Special emphasis is given on the interpretation of the effects of complex mixtures in target organs of diplopods. A semiquantitative analysis for the evaluation of histopathological changes in the perivisceral fat body was proposed. The sample-induced histopathological and ultrastructural changes in individuals exposed to it, and the severity of the effects was positively related to the exposure time, resulting in the deaths of exposed individuals after 90 days. Thus, the results indicate the need for caution in the use of biosolids as well as the need for improving waste management techniques, so they will produce environmentally innocuous final products.
显示更多 [+] 显示较少 [-]Trends in health burden of ambient particulate matter pollution in Iran, 1990–2010: findings from the global burden of disease study 2010 全文
2015
Poursafa, Parinaz | Kelishadi, Roya | Ghasemian, Anoosheh | Sharifi, Farshad | Djalalinia, Shirin | Khajavi, Alireza | Nejatifar, Masoumeh | Asayesh, Hamid | Mansourian, Morteza | Qorbani, Mostafa | Anṣārī, Ḥusayn
This paper aims to report the assessment of trends in deaths and disability-adjusted life years (DALYs) attributed to ambient particulate matter (PM) pollution from 1990 to 2010 by sex and age in Iran. We used the data of the Global Burden of Disease (GBD) 2010 Study, and then we extracted its data on Iran for the years 1990, 2005, and 2010. The proportion of deaths and the DALYs caused by specific risk factors were assessed by using the comparative risk assessment and calculating the attributed burden of exposure level to each risk factor compared with the theoretical minimum level of risk exposure. Uncertainties in distribution of exposure, relative risks, and relevant outcomes calculation were disseminated into the estimates of the attributable deaths and DALYs. We found that the age-standardized death rate attributed to ambient PM pollution decreased to 27.90 cases per 100,000 populations from 1990 to 2010 [86, 95 % uncertainty interval (UI) 76–97 to 62; 95 % UI 54–71 per 100,000 populations, respectively]. This was mainly because of greater decrease in cardiovascular diseases (CVDs) than in the other diseases attributed to PM pollution. Despite a decrease in the total DALYs and mortality rate attributed to PM pollution, the death percent increased by 6.94 %, 95 % UI 6.06–7.90 % from 1990 to 2010. The number of the DALYs and death in age groups of more than 70 years increased in 2010 compared to that in 1990. The median percent change of the DALYs and death for all age groups shows that the DALYs and death increased by 6 % (95 % UI 8–19 %) and 45 % (95 % UI 30–60 %), respectively, in 2010 in comparison to that in 1990. The increase in the DALYs and mortality attributable to PM pollution emphasizes the necessity of the effective interventions for improving air quality, as well as for increasing the public awareness to reduce the exposure of vulnerable age groups to PM pollution.
显示更多 [+] 显示较少 [-]Water and acrylamide monomer transfer rates from a settling basin to groundwaters 全文
2015
Binet, Stéphane | Bru, Kathy | Klinka, Thomas | Touzé, Solène | Motelica-Heino, Mickael
The aim of this paper was to estimate the potential leakage of acrylamide monomer, used for flocculation in a settling basin, towards the groundwaters. Surface–groundwater interactions were conceptualized with a groundwater transport model, using a transfer rate to describe the clogged properties of the interface. The change in the transfer rate as a function of the spreading of the clogged layer in the settling basin was characterized with respect to time. It is shown that the water and the Acrylamide transfer rate are not controlled by the spreading of the clogged layer until this layer fully covers the interface. When the clogged layer spreads out, the transfer rate remains in the same order of magnitude until the area covered reaches 80 %. The main flux takes place through bank seepage. In these early stage conditions of a working settling basin, the acrylamide flux towards groundwaters remains constant, at close to 10 g/year (±5).
显示更多 [+] 显示较少 [-]Comparison of waterborne and in ovo nanoinjection exposures to assess effects of PFOS on zebrafish embryos 全文
2015
Li, Yabing | Han, Zhihua | Zheng, Xinmei | Ma, Zhiyuan | Liu, Hongling | Giesy, John P. | Xie, Yuwei | Yu, Hongxia
Since perfluorooctane sulfonate (PFOS) had been detected in eggs of seabirds and fish, toxicity of waterborne PFOS to embryonic development of zebrafish (Danio rerio) was investigated. However, because assessment of effects by use of dietary exposure of adults is time-consuming and expensive, a study was conducted to compare effects on embryos via nanoinjection and waterborne exposure. Nanoinjection, in which small amounts of chemicals are injected into developing eggs, was used to incorporate PFOS into the yolk sac of embryos of zebrafish. Effects of PFOS during the period of development of the embryo were assessed within 96 h post-fertilization (hpf). PFOS significantly retarded development of embryos of zebrafish and resulted in abnormalities as well as lethality of developing embryos. Both methods of exposure, waterborne and nanoinjection, resulted in similar dose-dependent effects. Some sublethal effects, such as edema at 48 hpf, delayed hatching, and curvature of the spine was observed after 72 hpf. In ovo, nanoinjection was deemed to be an accurate method of exposure for controlling the actual internal dose for study of adverse effects, which closely mimicked responses to waterborne exposure of zebrafish embryo to PFOS.
显示更多 [+] 显示较少 [-]Catalog of total excitation–emission and total synchronous fluorescence maps with synchronous fluorescence spectra of homologated fluorescent pesticides in large use in Morocco: development of a spectrometric low cost and direct analysis as an alert method in case of massive contamination of soils and waters by fluorescent pesticides 全文
2015
Foudeil, S. | Hassoun, H. | Lamhasni, T. | Ait Lyazidi, S. | Benyaich, F. | Haddad, M. | Choukrad, M. | Boughdad, A. | Bounakhla, M. | Bounouira, H. | Duarte, R. M. B. O. | Cachada, A. | Duarte, A. C.
Catalog of total excitation–emission and total synchronous fluorescence maps with synchronous fluorescence spectra of homologated fluorescent pesticides in large use in Morocco: development of a spectrometric low cost and direct analysis as an alert method in case of massive contamination of soils and waters by fluorescent pesticides 全文
2015
Foudeil, S. | Hassoun, H. | Lamhasni, T. | Ait Lyazidi, S. | Benyaich, F. | Haddad, M. | Choukrad, M. | Boughdad, A. | Bounakhla, M. | Bounouira, H. | Duarte, R. M. B. O. | Cachada, A. | Duarte, A. C.
The purpose of this research is to develop a direct spectrometric approach to monitor soils and waters, at a lower cost than the widely used chromatographic techniques; a spectrometric approach that is effective, reliable, fast, easy to implement, and without any use of organic solvents whose utilization is subject to law limitation. It could be suitable at least as an alert method in case of massive contamination. Here, we present for the first time a catalog of excitation–emission and total synchronous fluorescence maps that may be considered as fingerprints of a series of homologated pesticides, in large use in Morocco, aiming at a direct detection of their remains in agricultural soils and neighboring waters. After a large survey among farmers, agricultural workers and product distributors in two important agricultural regions of Morocco (Doukkala-Abda and Sebou basin), 48 commercial pesticides, which are fluorescent, were chosen. A multi-component spectral database of these targeted commercial pesticides was elaborated. For each pesticide, dissolved in water at the lowest concentration giving a no-noise fluorescence spectrum, the total excitation-emission matrix (TEEM), the total synchronous fluorescence matrix (TSFM) in addition to synchronous fluorescence spectra (SFS) at those offsets giving the highest fluorescence intensity were recorded. To test this preliminary multi-component database, two real soil samples, collected at a wheat field and at a vine field in the region of Doukkala, were analyzed. Remains of the commercial Pirimor (Carbamate) and Atlantis (Sulfonylurea) were identified by comparison of the recorded TEEM, TSFM, and SFS to those of the preliminary catalog at one hand, and on the basis of the results of a field pre-survey. The developed approach seems satisfactory, and the fluorimetric fingerprint database is under extension to a higher number of fluorescent pesticides in common use among the Moroccan agricultural regions.
显示更多 [+] 显示较少 [-]Catalog of total excitation-emission and total synchronous fluorescence maps with synchronous fluorescence spectra of homologated fluorescent pesticides in large use in Morocco: development of a spectrometric low cost and direct analysis as an alert method in case of massive contamination of soils and waters by fluorescent pesticides 全文
2015 | 1000
Foudeil, S. | Hassoun, H. | Lamhasni, T. | Ait Lyazidi, S. | Benyaich, F. | Haddad, M. | Choukrad, M. | Boughdad, A. | Bounakhla, M. | Bounouira, H. | Duarte, R. M. B. O. | Cachada, A. | Duarte, A. C.
The purpose of this research is to develop a direct spectrometric approach to monitor soils and waters, at a lower cost than the widely used chromatographic techniques; a spectrometric approach that is effective, reliable, fast, easy to implement, and without any use of organic solvents whose utilization is subject to law limitation. It could be suitable at least as an alert method in case of massive contamination. Here, we present for the first time a catalog of excitation– emission and total synchronous fluorescence maps that may be considered as fingerprints of a series of homologated pesticides, in large use in Morocco, aiming at a direct detection of their remains in agricultural soils and neighboring waters. After a large survey among farmers, agricultural workers and product distributors in two important agricultural regions of Morocco (Doukkala-Abda and Sebou basin), 48 commercial pesticides, which are fluorescent, were chosen. A multi-component spectral database of these targeted commercial pesticides was elaborated. For each pesticide, dissolved in water at the lowest concentration giving a no-noise fluorescence spectrum, the total excitation-emission matrix (TEEM), the total synchronous fluorescence matrix (TSFM) in addition to synchronous fluorescence spectra (SFS) at those offsets giving the highest fluorescence intensity were recorded. To test this preliminary multi-component database, two real soil samples, collected at a wheat field and at a vine field in the region of Doukkala, were analyzed. Remains of the commercial Pirimor (Carbamate) and Atlantis (Sulfonylurea) were identified by comparison of the recorded TEEM, TSFM, and SFS to those of the preliminary catalog at one hand, and on the basis of the results of a field pre-survey. The developed approach seems satisfactory, and the fluorimetric fingerprint database is under extension to a higher number of fluorescent pesticides in common use among the Moroccan agricultural regions.
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