Sediment imbalances and flooding risk in European deltas and estuaries     

Albert Rovira  Rhoda Ballinger  Carles Ibáñez  Paul Parker  M. Dolores Dominguez  Xavier Simon  Andrzej Lewandowski  Boris Hochfeld  Marian Tudor  Liesbeth Vernaeve 《Journal of Soils and Sediments》2014,14(8):1493-1512

Purpose

We analysed the status of current water and sediment management practices in six deltas and estuaries, which were part of the European DELTANET, INTERREG-funded network.

Materials and methods

These systems—the Danube, Ebro and Vistula deltas and the Elbe, Minho and Severn estuaries—represent different geographic regions of Europe. This enables comparison between the sites’ approaches to common coastal issues, notably those associated with sediment budgets, contamination and flood risk. Based on documentary analysis, workshop events and expert discussion, we employ a simple classification scheme to distinguish between levels of risk from these aspects.

Results

We suggest that flood risk is the most significant risk, followed by upstream sediment retention and sediment aggradation. Chemical contamination, though less severe, is not unimportant. Key management issues include a lack of environmental quality standards for sediment and suspended particulate matter, as well as the limited deployment of monitoring programmes, regular sediment sampling and associated chemical analyses.

Conclusions

These include both general and specific recommendations. Within these, the limited scope of integrated plans that aim for sustainability of the respective systems is highlighted. It is suggested that these do not challenge traditional, classical engineering approaches sufficiently. Nor do they address the origin of many environmental problems, especially those which are closely linked to short-term political and economic priorities.  相似文献   

Comparison of acetamide and dimethylsulfoxide as cryoprotectants of European brown hare (Lepus europaeus) spermatozoa     

Kozdrowski R  Dubiel A  Noszczyk-Nowak A 《The Journal of reproduction and development》2009,55(1):45-49

The aim of the present study was to assess the effect of dimethylsulfoxide (DMSO) and acetamide on the post-thaw properties of hare semen and to perform an AI trial with frozen-thawed semen. Semen was collected under general anaesthesia by the electroejaculation method from 6 males. Immediately after collection, the semen was diluted with an extender containing the following components: 250 mM Tris, 80 mM citric acid, 70 mM glucose, 1.0 M DMSO, egg yolk (17% v/v) and kanamycin (80 mg/l); this extender was used for Protocol I (n=17). In Protocol II (n=15), the DMSO was replaced with 1.0 M acetamide. Immediately after thawing and after incubation for 90 and 180 min at 37 C, the properties of semen were evaluated by computer-assisted semen analysis, and the percentage of viable, acrosome intact spermatozoa was evaluated using flow cytometry. During the 3-h incubation, the percentages of motile spermatozoa and spermatozoa with progressive motility were significantly higher in Protocol I (P<0.01). Immediately after thawing, path and straight velocity were significantly higher in Protocol I (P<0.01), as was the curvilinear velocity (P<0.05). The amplitude of lateral head displacement was higher after 3-h incubation in Protocol I (P<0.05), and no differences in beat cross frequency were found between Protocol I and II at any incubation time. The percentage of viable, acrosome intact spermatozoa determined with flow cytometry was higher in Protocol I (P<0.01) at all incubation times. As a result of artificial insemination with the semen frozen with DMSO as a cryoprotectant, two out of three inseminated females delivered two healthy young each. Following artificial insemination with the semen frozen with acetamide as a cryoprotectant, two out of three inseminated females delivered one healthy young each. On the basis of the results, it should be stated that DMSO ensures better post-thaw properties of hare spermatozoa than acetamide.  相似文献   

Tree reactions and dune movements: Slowinski National Park,Poland   总被引：2，自引：0，他引：2  

Marcin Koprowski  Vanessa Winchester  Andrzej Zielski 《CATENA》2010

The effects on tree growth of both climatic and non-climatic variables were investigated in relation to dune dynamics at three sites on the Czolpinska dune in the Slowinski National Park, Poland where aeolian sediments are invading a forest of Scots Pine (Pinus sylvestris L.). We found that where dune advance was relatively rapid, tree vitality declined after stem burial was over 1.9 m, but where advance was under 1 m/yr survival was remarkably increased, one tree survived, albeit with thinning needles, after an estimated 11.4 m burial. Below sand-surface stem discs, cut 0.5 m apart, from a heavily suppressed tree revealed a difference in narrow-ring reactions of up to 2 years over a 2 m burial distance; the discs also showed a time lag of 4 years before compression wood formation. Consequently, when estimating sand-movement rates we discounted compression wood reactions; we also excluded climatic events and pest infestations. The remaining data supplied a sand-advance rate at Site 1 from 2.4 to 3.5 m/yr. At Site 2, rates were from 1.2 to 2.5 m/yr, with a direct measurement of 0.3 m/yr between 2006 and 2007. At Site 3 rates were from 0.3 to 1.2 m/yr, with dune migration here virtually at a standstill over the last seven years. Direct measurement of sand movement (3.03 m/yr) at Site 1 was slower than the lowest rate (3.5 m/yr) previously recorded by Borówka (1980) for the larger dune system.  相似文献   

The influence of \upbeta-hydroxy- \upbeta-methylbutyrate (HMB) on cell-mediated immunity in tench Tinca tinca (L.): in vitro and in vivo study     

Andrzej K. Siwicki  Zdzisław Zakęś  John C. Fuller Jr  Steven Nissen  Krzysztof Kazuń  Edward Głąbski 《Aquaculture International》2006,14(1-2):153-161

$\upbeta$ -Hydroxy- $\upbeta$ -methyl butyrate (HMB) has been shown to counteract many of the negative effects of intensive fish production methods and results in increased growth and protection against diseases. In the present study, the in vitro and in vivo effect of HMB on the immunocompetence cell activity in tench Tinca tinca (L.) was examined. In the in vitro study pronephric phagocytes and lymphocytes were isolated from the fish and grown in culture medium (RPMI-1640) containing 0, 0.1, 1, 5, 10, 25, 50 or $100\,\upmu$ g HMB cm^?3 of medium. The effects of HMB on the respiratory burst activity (RBA), the potential killing activity (PKA) and lymphocyte proliferation stimulated by concanavalin A (ConA) or lipopolysaccharide (LPS) were examined. The in vitro study showed that HMB increased the RBA and PKA of the phagocytes, compared to the medium over that of cells grown without HMB. Lymphocyte proliferation stimulated by ConA and LPS was also increased approximately when HMB was added to the culture medium at concentrations between 10 and $100\,\upmu$ g HMB cm^?3. In the in vivo study fish were fed daily with pellets containing HMB at doses 0, 10, 25 and 50 mg kg^?1 body weight day^?1. The study showed that HMB statistically increased the RBA and PKA and highest activity at 50 mg kg^?1 body weight day^?1 were observed. Also lymphocyte proliferation stimulated by ConA and LPS were maximally stimulated at dose 50 mg kg^?1 body weight day^?1. In conclusion, the current study shows that HMB could potentially improve immunocompetence cell activity in tench through increased cell proliferation and functionality.  相似文献   

Effect of mechanical damage on vigor,physiological parameters,and susceptibility of oat (<Emphasis Type="Italic">Avena sativa)</Emphasis> to <Emphasis Type="Italic">Fusarium culmorum</Emphasis> infection     

Tomasz Warzecha  Andrzej Zieliński  Edyta Skrzypek  Tomasz Wójtowicz  Maria Moś 《Phytoparasitica》2012,40(1):29-36

Vigor and selected physiological parameters (content of phenolic compounds, soluble sugars, chlorophyll a and b, and carotenoids) of eight naked and two husked oat cultivars harvested at 15% moisture content were determined. Oat seeds were threshed using two rotational speeds of the threshing drum: 1.6 m s⁻¹ (LS) and 2.4 m s⁻¹ (HS). They were then inoculated with a medium pathogenicity strain of Fusarium culmorum, strain IPO 348–01. In naked cultivars, the use of HS resulted in more severe mechanical damage; in consequence, seedling vigor decreased by 16%. In naked cultivars chlorophyll a and b and carotenoids content were significantly reduced—by more than 64%—when the HS was used. The inoculation caused over a 100% increase of carbohydrates in roots at LS but only a slight increase at HS. Phenolic compound content was twice as high in roots than in leaves after inoculation for both LS and HS. Area of microdamage and reduction of root fresh weight (f.wt.) are significantly correlated with biochemical parameters. Smaller microdamage area and root f.wt. reduction are connected with higher physiological parameters, which confirms lower seedling susceptibility to pathogen infection.  相似文献   

Thermal stability of 5-o-caffeoylquinic acid in aqueous solutions at different heating conditions     

Dawidowicz AL  Typek R 《Journal of agricultural and food chemistry》2010,58(24):12578-12584

Chlorogenic acid is a naturally occurring phenolic compound found in all higher plants. This component, being the ester of caffeic acid with quinic acid, is an important biosynthetic intermediate and plays an important role in the plant's response to stress. Potential uses of chlorogenic acid are suggested in pharmaceuticals, foodstuffs, feed additives, and cosmetics due to its recently discovered biomedical activity. This finding caused new interest in chlorogenic acid properties, its isomers, and its natural occurrence. It has been found that as many as nine compounds (chlorogenic acid derivatives and its reaction product with water) can be formed from 5-o-caffeoylquinic acid during the heating of its water solution. Three of them, two hydroxylated 5-o-caffeoylquinic acid derivatives and 4,5-dicaffeoylquinic acid, have been not reported, yet. The amount of each formed component depends on the heating time and temperature. The presented results are important for researchers investigating plant metabolism and looking for new plant components. The transformation product can be mistakenly treated as a new component, not found before in the examined plant, or can be a cause of erroneous quantitative estimations of plant composition.  相似文献   

Aluminium uptake by roots of rye seedlings of differing tolerance to aluminium toxicity     

Andrzej Anioł 《Euphytica》1996,92(1-2):155-162

Summary The aluminium accumulation pattern was studied in roots and root tips of rye seedlings from two inbred lines, differing in Al-tolerance and their F₁ hybrid.This investigations were undertaken in order to find whether the mechanism preventing root tips from to high Al-accumulation and damage to apical meristem observed in Al-tolerant isoline of wheat is also operating in rye. Al-uptake into the root tissue was studied in nutrient solution experiments during 24 h of incubation in solution containing aluminium. After Al-incubation roots were harvested, separated into root tips and basal parts, and aluminium content in root tissue was determined after wet digestion using catechol violet colorimetric method. It was found, that at low external Al-concentration in rye roots the mechanism preventing root tips from Al-accumulation and Al-damage operates, similarly as in Al-tolerant wheat isoline. But contrary to wheat in rye seedlings functioning of this mechanism was observed in both Al-tolerant and Al-sensitive lines. It is concluded that observed mechanism of the inhibition of Al-accumulation in apical part of roots plays much more important role in Al-tolerance mechanism in wheat than in rye.Abbreviations EDTA ethylenediaminetetraacetic acid - NIL near-isogenic line  相似文献   

Why asparagine needs carbohydrates to generate acrylamide   总被引：15，自引：0，他引：15  

Yaylayan VA  Wnorowski A  Perez Locas C 《Journal of agricultural and food chemistry》2003,51(6):1753-1757

Structural considerations dictate that asparagine alone may be converted thermally into acrylamide through decarboxylation and deamination reactions. However, the main product of the thermal decomposition of asparagine was maleimide, mainly due to the fast intramolecular cyclization reaction that prevents the formation of acrylamide. On the other hand, asparagine, in the presence of reducing sugars, was able to generate acrylamide in addition to maleimide. Model reactions were performed using FTIR analysis, and labeling studies were carried out using pyrolysis-GC/MS as an integrated reaction, separation, and identification system to investigate the role of reducing sugars. The data have indicated that a decarboxylated Amadori product of asparagine with reducing sugars is the key precursor of acrylamide. Furthermore, the decarboxylated Amadori product can be formed under mild conditions through the intramolecular cyclization of the initial Schiff base and formation of oxazolidin-5-one. The low-energy decarboxylation of this intermediate makes it possible to bypass the cyclization reaction, which is in competition with thermally induced decarboxylation, and hence promote the formation of acrylamide in carbohydrate/asparagine mixtures. Although the decarboxylated Amadori compound can be formed under mild conditions, it requires elevated temperatures to cleave the carbon-nitrogen covalent bond and produce acrylamide.  相似文献   

Field Data of Hydrogen Peroxide Concentrations in Urban and Mountain Air in Southwestern Poland     

Sówka  Izabela  Zwoździak  Jerzy  Zwoździak  Anna  Szczurek  Andrzej 《Water, air, and soil pollution》2004,155(1-4):321-338

The concentrations of ambient gas-phase hydrogen peroxide were measured during the summer of 1998, 1999 and 2000. The experiments were performed in the city of Wroclaw and in the vicinity of Mount Szrenica, 1362 m a.s.l., Poland. Analysis was carried out by the chemiluminescence method. Typical mean ranges of 30 min H₂O₂ concentrations measured were 1.4–6.0 μg m^-3 at Mount Szrenica, whereas in the urban atmosphere H₂O₂ concentrations were in the range of 2.7–11.7 μg m^-3. In the case of the urban atmosphere, H₂O₂ concentrations were well correlated only with solar radiation and temperature. In the mountain air, H₂O₂ concentrations increased along with the increase of temperature, O₃, CO and the decrease of humidity. The diurnal variation was not only caused by photochemicalprocesses.  相似文献   

The taxonomy of Protura present status and future problems: Proceedings of the Xth international Colloquium on Apterygota, České Budějovice 2000: Apterygota at the Beginning of the Third Millennium     

Andrzej Szeptycki   《Pedobiologia》2002,46(3-4)

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