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Gudelj I.,HIPALAB D.o.o. | Hrenovic J.,Prirodoslovno matematicki Fakultet Sveucilista U Zagrebu | Dragicevic T.,Prehrambeno biotehnoloski Fakultet Sveucilista U Zagrebu | Delas F.,Prehrambeno biotehnoloski Fakultet Sveucilista U Zagrebu | And 2 more authors.
Arhiv za Higijenu Rada i Toksikologiju | Year: 2011

Intense industrial development has been accompanied by the production of wastewaters of very complex content, which pose a serious hazard to the environment, put at risk sustainable development, and call for new treatment technologies that would more effectively address the issue. One particular challenge in terms of science and technology is how to biodegrade xenobiotics such as azo dyes, which practically do not degrade under natural environmental conditions. These compounds tend to bioaccumulate in the environment, and have allergenic, carcinogenic, mutagenic, and teratogenic properties for humans. Removal of azo dyes from effluents is mostly based on physical-chemical methods. These methods are often very costly and limited, as they accumulate concentrated sludge, which also poses a significant secondary disposal problem, or produce toxic end-products. Biotechnological approach may offer alternative, lowcost biological treatment systems that can completely biodegrade and detoxify even the hard-to-biodegrade azo dyes.

Vukelic J.,University of Zagreb | Alegro A.,Prirodoslovno Matematicki Fakultet Sveucilista u Zagrebu | Segota V.,Prirodoslovno Matematicki Fakultet Sveucilista u Zagrebu | Sapic I.,University of Zagreb
Sumarski List | Year: 2010

Common beech (Fagus sylvatica) forms a strong vegetation belt in the sub-alpine region of the Croatian Dinaric range, with natural forests of common spruce (Picea abies) occurring as azonal communities in some specific localities of this belt. The association Laserpitio krapfii-Piceetum Vukelić, Alegro et Šegota 2010 inhabits sinkholes and northern, colder and shadier slopes from 1,100 to 1,400 m above the sea, while shady and open ridges and peaks above 1,400 m are occupied by the spruce forest described by S. Bertović (1975) under the name of Calamagrostio variae-Piceetum dinaricum Bertović 1975. Bertović's name of the association is illegitimate (articles 31 and 34a, International Code of Phytocoenological Nomenclature - ICPN, Weber, Moravec and Theurillat 2000) since the name was already used by Schweingruber in 1972 for an association in the Randalpen in Switzerland. One of the objectives of this research was to revise the nomenclature and propose a new name for the phytocoenosis (Hyperico grisebachii-Piceetum), as well as define the diagnostic species and other features. We used a method of the Zurich-Montpellier Phytocoenological School with a six-degree scale. The floral composition was classified according to the social affiliation of the species. The plant nomenclature was adjusted to the Flora Croatia database (Nikolić 2010), while mosses were adjusted according to Koperski et al. (2000). The association Hyperico grisebachii-Piceetum is distributed above an altitude of 1,400 m (slightly lower on Samarske Stijene). It grows on distinctly rocky peaks, ridges, hooks, karrens, and upper, steep and sun-exposed slopes. The sites of this association are basically characterized by the rockiness of the terrain, which almost always exceeds 40 %. This contributes significantly to the broken tree canopy layer and to the composition of shrubs and ground vegetation (Figure 1). The soils mostly consist of different subtypes of calcomelanosol, from organogenic, over organomineral to browned soils, and less frequently of shallow calcocambisol (Bakšić et al. 2010). According to the macroclimatic features of the Zavižan set, the average annual temperature is 3.5 °C and the average annual precipitation amount is 1,898 mm (Vučjak meteorological station on Northern Velebit - 1,594 m, period 1061-1990). The ecological amplitude of the occurrence of the community is very narrow, whereas the specific relief, pedological and climatic conditions are unfavourable for the successful growth of forest vegetation. Ten phytocoenological relevés (Table 1, relevés 1-6, Zavižan area; 7 and 8, Smrčeve Doline area; 9 and 10, Samarske Stijene area) contain 153 species of higher plants and 31 moss species. The interrupted tree layer is completely dominated by spruce, while the shrub layer, in addition to the species from the tree layer, contains further 18 species. Lonicera caerulea inc. subsp. borbasiana, Clematis alpina, Vaccinium myrtillus, Rosa pendulina, Salix appendiculata, Rubus idaeus, Sambucus racemosa and Juniperus communis subsp. alpina feature in more than two thirds of the relevés. From the sociological standpoint, there is a prevalence of socalled "picetal" (spruce) species, characteristic for spruce forests of the major part of Europe. Together with mosses, there are 38 such species in all. They are decisive for the sin-systematic position of the association and their participation is higher than in the marginal phytocoenosis Laserpitio krapfii-Piceetum. The species Calamagrostis varia, Cirsium erysithales, and even Carex ornithopoda, which belong to the order Erico-Pinetalia, deserve special mention in terms of participation and cover. Of other higher categories, the order Fagetalia Pawl. 1928 and lower categories consist of 31 species, of which 7 occur in over 40% of the relevés. The alliance Adenostylion Br.-Bl. 1925 and the order Adenostyletalia G. & J. Br.-Bl. 1931 are represented by 17 species, with 5 species occurring in over 40% of the relevés. The species of these syntaxa occur in a considerably lesser amount than is the case with the phytocoenosis Laserpitio krapfii-Piceetum mentioned above. The comparison of the newly-nominated phytocoenosis Hyperico grisebachii-Piceetum with Shwaingruber's Calamagrostio variae-Piceetum shows big differences, as well as their absolute independence. Over thirty species from the Dinaric Alps (e.g. Salix appendiculata, Sambucus racemosa, Lonicera caerulea subsp. borbasiana, Festuca bosniaca, Hypericum richeri subsp. grisebachii, Cardus acanthoides, Geranium macrorrhizum, Achillea clavene, Gentiana lutea subsp. symphyandra, Ribes alpinum and many others) are missing from stands of spruce forest with small-reed in the Austrian Alps (Willner and Grabherr 2007, columns 7 and 8, Table 34). On the other hand, these stands contain more than 100 species which were not recorded in the Dinaric association. Of these species, Larix decidua, Pinus sylvestris, Polygala chamaebuxus, Sesleria albicans, Homogyne alpina, Carex alba, Hepatica nobilis, Erica carnea, Campanula cochleariifolia, Ranunculus nemorosus and others are particularly prominent in terms of occurrence or participation. The investigated spruce association differs from subalpine spruce forests growing in Slovenia (Zupančič 1999) and in other Dinaric regions (Vukelić, Alegro and Šegota 2010). To select diagnostic species of the association, we compared ten relevés from Table 1 and used the results of research into the forest vegetation of south-eastern Europe, primarily that of Fukarek (1964), Stefanović (1970), Zupanč ič (1980, 1999), Zupančič and Acceto (1994), Vukelić, Alegro and Šegota (2010) and other phytocoenologists. Special mention should be made of a broader group of differentiating species which characterize the subalpine, open-canopy rocky sites and which either do not occur in other spruce communities or are present to a much lesser degree. These include in the first place Juniperus communis subsp. alpina, Salix apendicullata, Sambucus racemosa, Hypericum richeri subsp. grisebachii, Achillea clavenae, Gentiana lutea subsp. symphyandra, than Festuca bosniaca, Cardus acanthoides, Carlina acaulis subsp. caulescens, Asplenium fissum, Melampyrum velebiticum and others. Not all of them are primarily forest species; the sites of this spruce forest are frequently interspersed with mountain clearings and massive blocks whose cracks are inhabited by these species. In relation to other spruce forests in Croatia and wider, there is also a group of forest species with high participation and cover that includes Calamagrostis varia, Polystychum lonchitis, Adenostyles alpina and Vaccinium vitis-idaea. These species play an important role in the identification and differentiation of this association, although they cannot be determined as differentiating since they are also present in other Dinaric phytocoenoses. St John's wort, Hypericum richeri Vill. subsp. grisebachii (Boiss.) Nyman, proved to be the most suitable species for nominating the association. Its participation and amounts are much higher than in the related phytocoenoses, while its eco-indicator properties are ideally suited to the site conditions of the association. Moreover, it has not been used in the nomination of common spruce communities. In forest communities of Croatia, Hypericum richeri subsp. grisebachii is found in mugo pine stands and in the investigated spruce association. Regardless of the same sinsystematic affiliation, these two associations differ profoundly. Based on the above, the valid name of the analyzed association is Hyperico grisebachii-Piceetum abietis (Bertović 1975) nom. nov. hoc loco. We propose Bertović's relevé No 5 in Table 17 (Bertović 1975, p. 34) to be the nomenclatural type (lectotypus hoc loco), This will solve the problem of the name and independent status of the association. In the syntaxonomic sense, it belongs to the alliance Vaccinio-Piceion, order Vaccinio-Piceetalia and class Vaccinio-Piceetea. The phytocoenosis does not have any commercial importance, but is of high protective and natural-scientific significance. The most important stands are found in North Velebit National Park, but the association also occurs sporadically in Samarske Stijene on Bjelolasica and in the Smrekovac area in the Risnjak massif. The composition of the phytocoenosis is not uniform across the entire distribution range. The high ridges on which it grows are relatively distant enclaves with their specific geobotanical and horological features.

Pejnovic D.,Prirodoslovno matematicki Fakultet Sveucilista U Zagrebu | Krapinec K.,University of Zagreb | Slamar M.,University of Zagreb
Sumarski List | Year: 2010

Numbering 50,000, hunters in Croatia are a sizeable and proportionately influential social group. They are bound by similar modes of behaviour in their leisure time, a common space of activity (hunting grounds) and identical spatial impact (hunting management zones and the associated structures), wherein they constitute a clearly distinguished and defined socio-geographic group. From 2001 to 2007 we found slow but statistically significant growth of number of hunters (r = 0,66; p < 0,05). Trends in the number of hunters in Croatia since the early 1960s have been characterised by significant fluctuations, with three basic and discernible stages: growth in their numbers up to the onset of the 1990s, when the largest number of hunters in the history of Croatian hunting was recorded (100,409 hunters); a drastic decline during the wartime and post-war periods (during the 1990s); and light growth since the beginning of the current decade. In recent years, the number of hunters in Croatia has been continually growing. During the 2001-2007 period alone, the number grew by 10,916, or 27.4 %, which is average annual growth of 1,819 hunters, or 4.6% (Figure 1). The highest correlation (Table 2) exists between ratio of hunters to general population and population density(r = 0,93; p <0,05), respectively average number of citizens per settlement (r = 0,90; p<0,05). These results indicate that number of hunters in total population will be lower as population density is higher. In 2001 Ratio of hunters to general population was 1:117, but 2007 this ratio was 1:73. This ratio classifies Croatia in the middle on the European scale of portion of hunters in general population. The spatial distribution of hunters results from the interference of several factors, from natural/geographic features, through population density, phase of socio-economic development, degree of urbanisation/ruralisation and functional orientation of physical space, to the status and role of hunting traditions in the regional system of values. As a result of the cumulative causality of these factors, the highest number of hunters in 2001 at the county level was registered in Istria (3,246), followed by Primorje-Gorski Kotar County (3,005), while the lowest numbers were recorded in Varaždin (703) and Dubrovnik-Neretva Counties (994). From the geographic standpoint, fundamental significance is accorded to study of spatial differences in hunting intensity, both hunting-geographic (number of hunters per unit surface), and hunting-demographic intensity (number of hunters per 1,000 inhabitants). Comparative analysis at the county level shows the highest hunting-geographic intensity is characterised by Medimurje County, which records a spatial intensity 2.7 times higher than Croatia's average (185.3 hunters per 100 km2 of territory in the County, in relation to 67.4 in Croatia), while the lowest is in Virovitica-Podravina County, which lags behind the national average in equal measure (25.8 hunters per 100 km2 of territory in the County, in relation to 67.4 in Croatia). On the other hand, Lika-Senj County stands out with the highest hunting-demographic intensity, more than three times the Croatian average (27.9 hunters per 1,000 inhabitants in the County compared to 8.6 for Croatia as a whole). This county simultaneously records the highest coefficient of use of hunting-demographic potential among Croatia's counties, three times the country's average (34.3 effective per 1,000 potential hunters in the County, in comparison to 10.8 in Croatia as a whole), while the lowest coefficient of use of this potential, after the City of Zagreb (1.8 effective per 1,000 potential hunters), is Varaždin County (4.8 effective per 1,000 potential hunters). The results of survey research conducted in December 2007, which encompassed 2,132 hunters from 44 hunting associations from almost all Croatian counties, indicate that the primary drivers of hunting activities in Croatia are men between the ages of 45 and 65, with emphasis on the 50-54 age group, and an average age of 49, of whom most have completed secondary school and are employed, and largely reside in rural areas. The highest number of hunters became involved in this activity while in their twenties, motivated by the personal need for outdoor recreation, and they account for over one half of the total number of hunts during the season and they enjoy the support/understanding of their families for this manner of using their leisure time. The recent growth in the number of members of this social group in Croatia is a result of growing interest in hunting as an increasingly popular way to spend leisure time as the country undergoes increasing urbanisation. Growth in the number of hunters is accompanied by the correspondingly increased role of hunting as an instrument of sustainable development, both in terms of economic advancement and environmental protection, in the sense of preservation of biological diversity. This pertains in particular to Croatia's rural and more tourism-oriented regions, in which hunting has been traditionally and even economically important in the former, while in the latter it contributes as a selective form to diversification of the tourism product. Knowledge of the socio-demographic characteristics of hunters, above all the huntinggeographic and hunting-demographic intensity at the county level, is one of the fundamental conditions for examining the place and role of hunting in sustainable development in Croatia and its subordinate regional components. Greater familiarity with these characteristics should contribute to the more complex evaluation and planning of hunting activities in the country in compliance with the principle of sustainable development of geographic space and with sound practices in the more developed member states of the European Union.

Vukelic J.,University of Zagreb | Alegro A.,Prirodoslovno matematicki Fakultet Sveucilista U Zagrebu | Segota V.,Prirodoslovno matematicki Fakultet Sveucilista U Zagrebu
Sumarski List | Year: 2010

This research describes a new association of spruce with Laserpitium krapfii (Laserpitio krapfii-Piceetum abietis ass. nova). Occurring in the subalpine belt of northern Velebit, it reaches altitudes between 1,200 and 1,600 m. Here, the association is developed as a permanent stage under the strong influence of the microclimate of more humid, colder and shadier sites. Locally, it descends into sinkholes and lower slopes all the way to the beechfir forest (Omphalodo-Fagetum). It is generally incorporated within the belt of pre-alpine beech forest with large white buttercup (Ranunculo platanifoliae- Fagetum). Some stands are highly productive, but in a large part of the range the community has a protective character. The phytocoenosis Laserpitio krapfii-Piceetum has macro-climatic features of the prealpine beech forest, in whose belt it is situated. However, its occurrence is predominantly determined by the microclimate modified primarily by the relief, altitude and other geomorphological factors (Cindrić 1973). The average annual temperature of the subalpine belt of northern Velebit is 3.5 °C, and the average annual precipitation is 1,898 mm (in the period 1961-1990, data from the State Hydro-Meteorological Institute). The parent material is made up of limestone breccias and limestone-dolomite blocks which often resurface. The soil is organogenic and organomineral calcomelanosol in mosaic with calcocambisol. In relation to calcomelanosols of other forest communities in the Zavižan area, calcomelanosols in this community are the richest in total nitrogen and humus content. Martinović (in Cestar et. al. 1977) found neutral reaction and base saturated adsorption complex in the humus-accumulative horizon and in the cambic horizon in calcomelanosols. He attributes his finding to the fragmented dolomitized limestones and breccias which supply the soils with ample quantities of calcium. It is very important to point this out, because in relation to other spruce associations, the studied Velebit community is significantly richer in species of the order Fagetalia. The average soil pH determined in water for the depth layer of 0-5 cm amounts to 5.50.

Bosnjak I.,Prirodoslovno matematicki fakultet Sveucilista u Zagrebu | Ljubesic Z.,Prirodoslovno matematicki fakultet Sveucilista u Zagrebu
Hrvatske Vode | Year: 2015

The omnipresent bacterial organisms inhabit in large quantities all known habitats of the Earth, including those with the most extreme living conditions. In the world oceans, of particular importance is a group called cyanobacteria, which are picoplanktonic organisms whose size is under 2 pm, but which have a leading role in the primary production in the marine environment due to the photosynthesis process. One of the main roles in the process is played by the smallest, most numerous and most dominant marine species, Prochlorococcus marinus, which forms the very basis of the oceanic food chain. This remarkable pictoplanktonic organism was first discovered 25 years ago, while the presence of the genus Prochlorococcus in the Adriatic Sea was determined only in 2009. The most recent oceanographic research in the Southern Adriatic focuses on the study of the Levantine Intermediate Water current as the main component of the "Eastern Adriatic Current" circulation, which brings with it, among the plankton content, the genus Prochlorococcus as well. The primary aim of these investigations is the characterization of the genus Prochlorococcus as a bioindicator for efficient monitoring of the first indications of environmental changes in the circulation of the Levantine Intermediate Water current caused by the climate change.

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