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81.
Dalia-Marija Brazauskiene Valdas Paulauskas Nomeda Sabiene 《Journal of Soils and Sediments》2008,8(3):184-192
Background, aim, and scope Heavy metal (HM) mobility in soil depends on the HM species in it. Therefore, knowledge of the HM speciation in soil allows
the prediction of HM impact on the environment. HM speciation in soil depends on the metal chemical origin, soil texture,
and other factors such as the origin and level of soil contamination. Recently, the problem of organic waste utilization is
of great importance as the amount of this recyclable material is continually increasing. One of the possible ways of recycling
is the use of processed organic wastes for agricultural needs. In this research, aerobically composted sewage sludge was used,
the utilization of which is of essential importance. But one of the most serious restrictions is HM transfer from such material
to the soil. Therefore, a prediction of HM mobility in soil and its migration in the environment is an important issue when
using sewage sludge compost (SSC) in agriculture. Zn, Cu, and Pb speciation was performed according to the modified methodology
of Tessier et al. (Anal Chem 51:844–851, 1979) in two different (sandy and clay) soils with background HM amounts and in soil samples amended with aerobically digested
SSC to find out the predominant species of the investigated HM and to predict their potential availability.
Materials and methods The modified method of sequential extraction initially proposed by Tessier et al. (Anal Chem 51:844–851, 1979) is designed for HM speciation into five species where HM mobility decreases in the order: F1—exchangeable HM (extracted with 1 M MgCl2 at an initial pH of 7 and room temperature), F2—carbonate-bound HM (extracted with 1 M CH3COONa buffered to pH 5 at room temperature), F3—Fe/Mn oxide-bound HM (extracted with 0.04 M NH2OH·HCl at an initial pH of 2 at 96°C), F4—organic matter-complexed or sulfide-bound HM (extracted with 0.02 M HNO3 and 30% (v/v) H2O2 at a ratio of 1:1 and an initial pH of 2 at 85°C), and F5—the residual HM (digested with HNO3, HF, and HCl mixture). After digestion, HM amounts in solution were determined by atomic absorption spectrometry (AAS ‘Hitachi’).
Mixtures of uncontaminated soils of different textures (clay and sandy) with SSC in ratios 20:1, 10:1, and 5:1 were used to
simulate the land application with SSC. During a period of 7 weeks, changes in Zn, Cu, and Pb content within species were
investigated and compared weekly in soil–SSC mixtures with their speciation in pure soil and in the SSC.
Results Results in the SSC showed that more HM were found as mobile species compared to the soils, and in sandy soil, more were found
in the mobile species than in clay soil. But the HM speciation strongly depended on the metal chemical origin. According to
the potential availability, HM ranked in the following order: Zn>Pb>Cu. Zinc generally occurred in the mobile species (F1
and F3), especially in sandy soils amended with SSC, and changes of the Zn speciation were insignificant at the end of the
experiment. Pb transfer to insoluble compounds (F5) was evident in the SSC–soil mixtures. This confirms that Pb is extremely
immobile in the soil. However, the observed increase of Pb amounts in the mobile species (F1 and F2) during the course of
experiment shows a critical trend of Pb mobilization under anthropogenic influence. Copper in the soil–SSC mixtures had a
trend to form compounds of low mobility, such as organic complexes and sulfides (F4) and nonsoluble compounds (residual fraction
F5). Initially, the amounts of mobile Cu species (F1 and F2) increased in the soils amended with SSC, probably due to the
influence of SSC of anthropogenic origin with lower pH and high organic matter content, but Cu mobility decreased nearly to
the initial level again after 3–4 weeks. Hence, the soil has a great specific adsorption capacity to immobilize Cu of anthropogenic
origin.
Discussion Zn mobility and environmental impact was greater than that seen for Cu and Pb, while mobility of both Cu and Pb was similar,
but variable depending on soil texture and contamination level. The effect on the shift of HM mobility and potential availability
was greater in sandy SSC-amended soils than in clay soils and increased with an increasing amount of SSC.
Conclusions Usage of SSC for land fertilization should be strictly regulated, especially regarding Pb amounts.
Recommendations and perspectives The influence of SSC on Cu and Zn mobility and potential availability was more significant only in the case of sandy soil
with a higher SSC ratio. Nevertheless, this waste product of anthropogenic origin increased Pb mobility in all cases in spite
of only moderate Pb mobility in SSC itself. Therefore, aerobic processing of sewage sludge must be strictly regulated, especially
regarding Pb amounts, and SSC ratios must be in control regarding HM amounts when using it for on-land application. 相似文献
82.
In planta detection used to define the distribution of the European lineages of Phytophthora ramorum on larch (Larix) in the UK 下载免费PDF全文
Two genetically distinct evolutionary lineages of the oomycete pathogen Phytophthora ramorum are responsible for the major epidemic on larch (Larix spp.) in the UK: EU1 (historically widespread) and the recently identified EU2 (reported only from Northern Ireland and a small area in southwest Scotland). Methods for lineage discrimination have required pure cultures of P. ramorum but, as the pathogen is challenging to isolate from infected larch tissue, only limited data have been available on the distribution of EU2. In this study a protocol was developed to determine the lineage of P. ramorum in infected larch tissue without the need for isolation. The protocol was applied to 134 UK samples collected during 2013–14. In addition, lineage testing was applied to over 300 P. ramorum isolates cultured from a wide range of hosts between 2002 and 2012. Combined data confirmed that EU2 is restricted to Northern Ireland and a small area of southwest Scotland where it is the dominant lineage. There was no evidence of EU2 spread into England and Wales where only EU1 was found. However, EU2 was more widely distributed in southern and eastern parts of Scotland than previously reported. Furthermore, EU1 and EU2 were detected <10 km apart in larch plantations. This study provides the first reports of natural EU2 infection on European larch (Larix decidua), hybrid larch (Larix × eurolepis), beech (Fagus sylvatica), noble fir (Abies procera) and western hemlock (Tsuga heterophylla). 相似文献
83.
In a two-year (2005–2006) study conducted at three sites in central (Larissa) and northern (Alexandroupolis, Thessaloniki) Greece, we aimed to investigate the relationships between seedcotton yield and lint quality with leaf physiological traits (carbon isotope discrimination-Δ, ash content and K concentration). Eighteen lines with their original cultivars (Christina, Flora, Corona) were tested under the ultra-low density of 1.2 plants m−2. In combined data over years, a significant, positive correlation between seedcotton yield and Δ or ash content was found only in the driest and lowest-yielding site (Larissa), indicating that genotypes that keep their stomata open and in turn exhibit the highest Δ values, had an advantage in such environments. In pooled data from the two most productive sites (Thessaloniki and Alexandroupolis), which had the highest Δ and ash content values, evidenced a negative correlation between seedcotton yield and both physiological traits. Seedcotton yield was negatively related with leaf K concentration in Larissa and Alexandroupolis but no significant relationship was found in Thessaloniki where leaf K concentration was below adequacy limit. Δ was positively related with ash content which suggests that the latter could be a putative surrogate of Δ. Negative correlation between Δ and leaf K concentration was found in two out of three sites (Larissa and Thessaloniki) as well as between ash content and K in one site (Larissa). These findings suggest that K accumulation in leaves is not just a passive procedure via transpiration stream. Significant, linear relationships of each physiological trait between sites showed that genotypic ranking was constant in the three sites, an indication of heritability. Ash content had the highest significance levels and correlation coefficients. Even though significant genotypic differentiation was observed for the three physiological and two of the lint quality traits (i.e. fibre length, micronaire) determined in Alexandroupolis, only a weak, negative relationship between fibre length and leaf K concentration was evident. In sum, leaf physiological traits (Δ, ash content and K concentration) could not be reliably used for yield selection in cotton owing to site-specific effects, which prejudice the yield–physiological traits relationship. Ash content–Δ relationship merits further research in order the former to be established as a putative surrogate of Δ. 相似文献
84.
From weed biology to successful control: an example of successful management of Ludwigia grandiflora in Germany 下载免费PDF全文
Ludwigia grandiflora (water primrose), a native to the Americas, is one of the most important invasive alien aquatic plants in Europe. In Germany, a first population was found in an oxbow lake of the River Leda in Lower Saxony, north‐western Germany, in 2004. Ludwigia grandiflora formed both dense monospecific patches and mixed stands with native plants. A study on the biology of L. grandiflora documented that the plants regrow in spring from vegetative means only, even though viable seed production occurred. Hand weeding was successfully tested in different sampling sites as a sustainable management tool and subsequently used for the management of this species. Within 3 days, more than 99% of the biomass (25 tonnes of fresh mass) was harvested in 2013. Afterwards, a one‐day post‐treatment in the same year, two‐one‐day treatments in 2014 and one‐one‐day treatment in 2015 were made to harvest the regrown plants. After the first year, plant regrowth occurred only in one extremely muddy site, while in more than 99% of the water body, L. grandiflora was eradicated. Even though L. grandiflora was not completely eradicated from the water, a total eradication seems achievable within the next few years. The study documented the difficulties in the management of aquatic weeds, particularly in heterogeneous habitats with varying sediment structure. Management measures must be adapted to the infested habitat and species biology, which is mandatory for successful management of all aquatic weeds. 相似文献
85.
A preliminary evaluation of the European Non‐native Species in Aquaculture Risk Assessment Scheme applied to species listed on Annex IV of the EU Alien Species Regulation 下载免费PDF全文
G. H. Copp M. J. Godard I. C. Russell E. J. Peeler F. Gherardi E. Tricarico L. Miossec P. Goulletquer D. Almeida J. R. Britton L. Vilizzi J. Mumford C. Williams A. Reading E. M. A. Rees R. Merino‐Aguirre 《Fisheries Management and Ecology》2016,23(1):12-20
Developed for carrying out risk assessments under the European Commission (EC) Council Regulation No 708/2007 concerning the use of alien and locally absent species in aquaculture (ASR), the European Non‐native Species in Aquaculture Risk Assessment Scheme (ENSARS) is briefly summarised, and the ‘Organism’ module is applied to the 24 species listed in ASR's Annex IV. Four other ENSARS modules (Infectious Agent, Facility, Pathway, and Socio‐economic) were used to assess two case study species (European catfish Silurus glanis L. and red swamp crayfish Procambarus clarkii Girard). No Annex IV species was categorised as low risk, 10 as moderately low risk, 12 as medium risk, two as moderately high risk and none as high risk. The results are discussed and recommendations are made on further development of the scheme as well as the need to have multiple assessors of multidisciplinary expertise from the Member States concerned carry out the assessments using an approach similar to that carried out by EU Reference Laboratory proficiency tests. 相似文献
86.
欧盟经过多年的发展,制订了《食品卫生法》等多部食品安全领域的制度法规,这些制度法规是欧盟保障食品安全的法律基础。将我国与欧盟的动物源性产品中药物残留限量进行对比分析,结合我国国情及进出口大宗动物源性产品情况,学习并借鉴欧盟的药物残留限值设置方式方法,促进我国药物残留标准体系的健全完善。 相似文献
87.
中国茶叶出口欧盟面临的技术性贸易壁垒分析 总被引:2,自引:0,他引:2
介绍了中国茶叶出口欧盟所面临的技术性贸易壁垒的现状,剖析了中国茶叶出口遭受技术性贸易壁垒的内外原因,并提出了跨越壁垒的建议。 相似文献
88.
89.
欧盟食品安全管理体系给中国贝类产业健康发展的启示 总被引:1,自引:0,他引:1
系统回顾了欧盟食品安全管理框架及特点,介绍了欧盟食品安全的"农场到餐桌"原则的特点及表现,着重介绍了欧盟有关贝类的法规要求,并以典型案例介绍了欧盟贝类安全事故紧急处理过程。通过对海洋贝类安全问题的特殊性的剖析,分析了影响中国海洋贝类产业发展的制约因素,特别是海洋贝类安全管理问题对中国贝类出口的影响。借鉴欧盟管理机制,分析了建立海洋贝类风险分析评估机制体系对中国海洋贝类产业健康可持续发展的重要性,最后提出促进中国贝类产业可持续健康发展的几条建议。 相似文献
90.
2022年3月25日,欧盟药品管理局(EMA)兽医药品委员会(CVMP)发布了食品动物注射部位兽药残留指南,并于2022年8月1日正式生效。该指南代替旧版的注射部位兽药残留指南(EMA/CVMP/542/03-FINAL)。本文就新发布指南的背景、适用范围、法律依据、评价方法、残留研究及相关定义等内容进行介绍。 相似文献