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741.
The environmental occurrence and concentrations of cyanobacterial toxins (cyanotoxins) were investigated in the Czech Republic. Concentrations of microcystins (MCs), cylindrospermopsin (CYN) or saxitoxins (STXs) were determined immunochemically by ELISA assays in 30 water samples collected from the surface layers of 19 reservoirs during the summer season of 2010. MCs were detected in 18 reservoirs and 83 % of samples, with median and maximal concentration being 1.5 and 18.6 μg/L, respectively. The high frequency of MC occurrence coincided with prevalence of cyanobacterium Microcystis sp., which was detected in 87 % samples, followed by Dolichospermum (Anabaena) sp. observed in 33 % samples. CYN was detected by ELISA only in one sample at a concentration of 1.2 μg/L. STXs presence was indicated for the first time in Czech water reservoirs when the toxins were found at low concentrations (0.03–0.04 μg/L) in two samples (7 %) collected from two different reservoirs, where STXs co-occurred with MCs and eventually also with CYN. In both STX-positive samples, the phytoplankton community was dominated by Microcystis sp., but Dolichospermum sp. and/or Aphanizomenon sp. were also present as putative producers of STX and/or CYN. Cyanotoxins commonly occurred in Czech water reservoirs, and MCs frequently at concentrations possibly associated with human health risks. MCs were the most prevalent and abundant cyanotoxins, but also other cyanotoxins were detected, though sporadically. Further research and regulatory monitoring of cyanotoxins other than MCs is therefore required.  相似文献   
742.
The aim of this research was to assess the degree of heavy metal (cadmium, lead and mercury) contamination of wild boars from central Croatia and thereby conduct further tests to connect the contamination to oxidative stress occurrence. The highest cadmium concentration was noticed in the kidneys of older boars, the lead concentration was approximately the same in the liver and kidneys, but it was much higher than the concentration in the muscles, while the highest mercury concentration was measured in the kidneys of all wild boars. The correlation between the malondialdehyde (MDA) and the heavy metal concentrations was higher in tissue samples taken from younger animals (1 to 3 years of age) than in the tissue samples taken from older animals (5 to 6 years of age). In the kidneys of all wild boars there was a statistically significant connection between the MDA and cadmium concentration; in the kidneys of younger wild boars there was a statistically significant connection between the MDA and lead concentration. Further research on this topic should focus on MDA potential to find its use, not only as a contamination biomarker in the area of ecotoxicology, but also in the evaluation of the hygienic acceptability of animal products.  相似文献   
743.
Results of 2 years monitoring of 210Po and 210Pb activity concentrations in soft tissue of the species Mytilus galloprovincialis from Croatian part of the Adriatic coast are presented. The samples were collected at thirteen coastal stations (some of which are also a part of the Mediterranean Mussel Watch Project) in spring and autumn of 2010 and 2011. The collected mussels were ranging between 4 cm and 6 cm in shell length. After sample pre-treatment lead and polonium were radiochemically separated on Sr resin. 210Po was determined by alpha-particle spectrometry and 210Pb was determined, via 210Bi, by a low-level gas proportional counter. The results of 210Po activity concentrations were found to vary between (104 ± 11) and (1421 ± 81) Bq kg−1 dry weight while 210Pb activity concentrations were much lower and in range (8.2 ± 5.3)–(94.1 ± 29.8) Bq kg−1 dry weight. Higher 210Po and 210Pb activity concentrations were determined in spring period. The inter-site differences seen in their activity concentrations can be due to natural background levels of sites. The 210Po/210Pb activity concentration ratios in all cases exceeded unity for all mussel samples and ranged between 4.0 and 47.9.  相似文献   
744.
Summary Croatia, as a Mediterranean country in the south-eastern part of Europe, is an area with a characteristic flora and fauna. The ornithofauna of Croatia reflects that it is a breeding area for some of the globally endangered bird species, as well as a site for the spring/autumn passage and the wintering of European migratory birds. Many ornithologically significant localities are designated and there are 20 ornithological reserves and four wetland sites that are on the list of the Ramsar Convention.In Croatia, there are four governmental organizations dealing with scientific research on birds of which the Institute for Ornithology of the Croatian Academy, of Sciences and Arts is that with the longest tradition. There are also many non-governmental organizations dedicated to the protection of environment, but only the Croatian Society for Bird and Nature Protection is dedicated mostly to bird protection. There are not many sources of funding for research and the protection of birds; the chief source being the Ministry of Sciences and Technology of the Republic of Croatia.Croatia has to establish new legislation according to European criteria and The Hunting Law, The Nature Protection Law and The Environment Protection Law have been recently accepted in Parliament. International Conventions, such as Bern, Bonn and Washington, have yet to be adopted. Foreign, hunting tourism, especially organized by fishpond authorities, is believed to be killing large numbers of protected water birds. A red data book exists only for plants and mammals and this makes biological assessments difficult.With the end of military operations and the reintegration of the occupied areas of Croatia, an assessment of the damage to the national parks and nature reserves, and to nature in general, will be necessary. Bird and nature conservation in Croatia remains promising, provided the legal control of the Croatian government over the occupied parts of the country is restored soon and international organizations give assistance.Dr Jasmina Muini is Croatian by birth and she has studied in Paris, Oslo, and Zagred where she gained her PhD. She is a President of the Croatian Society for Bird and Nature Protection, a member of the Croatian Parliament Board for Environmental Protection, vice-president of the Scientific Council of the Zoological Garden in Zagreb, and a member of other Croatian environmental bodies. She is a leading authority on the ornithofauna of the Croatian wetlands.  相似文献   
745.
In this article, several findings on socio-economic conditions derived from national reports and a web-based questionnaire are discussed and related to the changing role of forestry and the future forest policy development. A number of Central and South-eastern European countries taking part in a SEE-ERA-NET project ReForMan project (www.reforman.de) participated in data acquisition: Austria, Bosnia and Herzegovina, Croatia, Germany, Serbia and Slovenia. The aim of the research was to illustrate the present structure of forestry sector, as well as investigate newly emerging topics in forestry of Central and South-eastern Europe. The results indicated certain patterns in attitudes and perceptions among stakeholders that can be related to socio-economic conditions defined for each country. Clear differences between member and non-member countries exist only in level of implementation of EU legislation. Results showed consensus on main threats to the forests among all countries, but also some country specifics in perceptions of factors influencing forestry, their importance and professional competencies. These results could be additionally explained by influence of historical conditions which shaped development of forest sector in SEE region especially in its organizational dimension as well as in perceived role of forestry expressed through recognition of main forest functions. The influence of European forest policy processes in the region is evident through adaptation of EU legislation and perceived implications of international processes on national levels. Based on this observation, two possible options for future development of the forestry sector can be foreseen: (i) focusing on the productive function of forests and fostering its' sustainable use; or (ii) putting an emphasis on environmental and social issues. In both cases supporting public participation in decision-making processes is recommendable. Another conclusion based on perceived medium to low professional competencies to cope with new topics, that there is lack of confidence and need for professional support in decisionmaking processes.  相似文献   
746.
In this paper, various spatial modelling techniques were applied to analyse changes in soil cover and their impact on soil erosion in the Oplenac wine-producing area in Serbia in the past (1985 and 2013) and in the future (with predictions for 2041). The Integrated Valuation of Ecosystem Services and Trade-offs Sediment Delivery Ratio (InVEST SDR) model and the Modules for Land Use Change Evaluation (MOLUSCE) model, integrated with methods of remote sensing, were successfully applied and were shown to be valid tools for predicting the impact of Land Use Land Cover (LULC) changes when estimating soil loss. The results revealed that the greatest impact of land use changes between 1985 and 2013 was on a reduction in areas under vineyards and an extension of meadow and pasturelands as an individual and social response to economic conditions during the research period. The forecast for 2041 reflected the trends observed in the previous period, with the greatest changes witnessing an increase in urban areas and a decrease in areas of arable land. It was also found that the effect of LULC changes on spatio-temporal patterns in the Oplenac wine-producing area did not have a major impact on soil loss, meaning this area, with its good agro-climatic characteristics, is suitable for the intensification of agricultural production.  相似文献   
747.
The objective of this paper is to study the hydrological characteristics and origin of the hydrogen sulphide spring water from the Split spa in Southern Croatia in 1987, 1988 and 2003. This paper presents the results of monitoring the content of chlorides and hydrogen sulphide as well as the temperature of the hydrogen sulphide spring water. Since the hydrogen sulphide content during the dry periods significantly differs from the hydrogen sulphide content during rainy periods, this paper also compares the results obtained for those two periods. Under the influence of great quantities of rainfall during cold periods (winter and the beginning of spring) the ratio between seawater and surface water changes and thus the reduction of chlorides and other minerals occurs. The lowered temperature also reduces hydrogen sulphide which can disappear completely. The concentration of 12‰ chlorides (76–94.4% days/year) and 12 mg/L hydrogen sulphide (66.7–88.9% days/year) has been taken as a limit value between water with a normal typical content and water in cold rainy periods. According to the monitoring results it can be concluded that hydrogen sulphide spring water consists of seawater and hydrogencarbonate surface water with a fairly constant content during dry periods while the hydrogencarbonate content increases during rainy periods.  相似文献   
748.
Phytoplankton distribution and environmental characteristics were determined in a shallow, highly stratified and oligotrophic estuary (Zrmanja, eastern Adriatic). Samples were collected in two contrasting seasons; winter (February 2000), when river discharge was high, and in summer (July 2003), a period of drought. Phytoplankton distribution was closely related to salinity gradients, nutrient levels, and water residence time. Microscopic analysis revealed that phytoplankton was composed mainly of marine diatoms, dinoflagellates, cryptophytes, green flagellates, and coccolithophorids. The dominant biomarker pigments were fucoxanthin, alloxanthin and 19'-hexanoyloxyfucoxanthin, while lower, but indicative contributions of peridinin and chlorophyll b were also noted. Maximum abundance and biomass were found in the middle estuary in winter and in the upper estuary in summer. The estuary is mostly P-limited. Development of chain-forming marine diatoms was evident in winter. Due to the reduced nutrient input in summer, the biomass accumulated in the upper estuary (1,000 ng chlorophyll a l(-1)) was composed mostly of nanoplanktonic unicellular diatoms, nanoplanktonic marine dinoflagellates, cryptophytes, and chlorophytes. The concentrations of about 200 ng l(-1) hex-fuco, suggested that the contribution of prymnesiophytes to total biomass was comparable to that of diatoms and dinoflagellates. In the middle estuary and coastal sea, PO(4) and TIN were 3.5 times lower, resulting in a fivefold decrease in biomass (<100 ng chlorophyll a l(-1)). The oligotrophic Zrmanja and other karstic rivers discharging in the eastern Adriatic Sea, provide insufficient source of nutrients and low productivity of the eastern Adriatic Sea.  相似文献   
749.
The objective of the investigations of the Jadro River, located in Croatia, was to estimate the nitrogen and phosphorus loads in the Jadro River spring and its streamflow by calculating the load in kg/day or tons/year and to compare this with the load for the maximum allowed concentrations (MAC) for drinking water (Official Bulletin, No 46/94) expressed in kg/day or tons/year.Daily pollution loads at the Jadro River spring for total N ranged from 0 to 304 kg, for NH3-N from 0 to 38 kg, for NO3-N from 0–1321 kg and for PO4-P from 0–92 kg in the period from September 1993 to September 2003. When compared with MAC loads the results prove that the Jadro River spring is not polluted by nitrogen compounds and phosphorus.The average annual load for total N ranged from 10 to 33 t, for NH3-N from 0.25 to 5.15 t, for NO3-N from 40 to 190 t, and for PO4-P from 0.3 to 11.5 t. The nitrogen compounds and phosphorus loads vary from one year to another without any constant decreasing or increasing trends. The annual average loads compared with the average annual MAC loads (especially for NH3-N and PO4-P) show that there were no threats of constant pollution of the spring.The loads for total N and PO4-P along the Jadro River flow from the spring to the fishpond entrance were monitored over a five year period from September 1999 to September 2004. The results show no regularities. The highest annual total nitrogen load of 45 t was recorded at the entrance to the fishpond during the 2002/2003 period. The highest annual PO4-P load of 10 t was measured at the Vidović Bridge during the 2003/2004 period; however, the concentrations of N and P did not exceed the MAC concentrations which are prescribed for drinking water.According to the investigation results of the daily and average annual loads compared with MAC loads for drinking water, it can be concluded that the Jadro River spring and its streamflow are not polluted by nitrogen and phosphorus.  相似文献   
750.
In order to assess the contribution of emission sources to the pollution of areas remote from industrial facilities, a combined approach of enrichment factor analysis and multivariate statistics was used for detecting the origin of heavy metal pollution in the Zlatibor ecosystem, in Serbia. Samples of moss (Pleurozium schreberi, Hylocomium splendens, Scleropodium purum, Hypnum cupressiforme and Thuidum delicatulum) and of topsoil (0-5 cm) were collected in 2005. The concentrations of seven heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined in moss and soil samples by atomic absorption spectrometry. The results obtained by enrichment factor analysis and two multivariate statistical methods, principal component analysis and cluster analysis, enabled discrimination of the lithologic and anthropogenic sources of heavy metals in the mosses. Enrichment factors, calculated to evaluate the contribution to the metal content in moss from anthropogenic sources, revealed pollution of the investigated area by Cd and Pb, originating from long-range transport and fossil fuel burning.  相似文献   
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