63 research outputs found
Pollination patterns of flora and vegetation in northern Croatia with reference to Apis mellifera
Pollination patterns i.e. the proportions of entomophilous, anemophilous, autogamous and hydrophilous plant species and those useful for the European honey bee (Apis mellifera L.) in the flora and vegetation of northern Croatia have been determined. The survey included 507 plant taxa, belonging to 95 plant families. The results show that most plant species depend on insect pollination (73.6%), followed by self-pollination (30%), wind (25%) and water pollination (0.6%). For some plant species there are one, two or more modes of pollination; the largest group consists of pure insect pollination (43%), followed by both insect and self-pollination (27%), pure wind pollination (22%), insect and wind pollination (2.6%), and so on. Overall, 54% of plant species useful to European honey bees were found, of which 51% provide pollen and 47% nectar. These results suggest that A. mellifera could be a potential pollinator for about half of the flora. Analysis shows significant differences in pollination patterns among habitat types and that most entomophilous plant taxa are found in grassland, forest and ruderal sites, indicating that these habitats are most important for pollinators. Other characteristics of plant species, such as flowering time, plant family, life form and origin, were also analysed to determine a possible relationship with pollination
The Zrmanja River Estuary (Adriatic Coast, Croatia) – the Need for Interdisciplinary Approach to Protection of Coastal Areas
The Zrmanja River estuary is a semi-enclosed bay immersed in a karstic landscape of the eastern Adriatic coast. It represents a highly indented system which includes part of the Zrmanja River, downstream from the Jankovića Buk, the Novigrad and the Karin Seas, and the strait connecting the Novigrad Sea with the Velebit Channel. The very fact that the estuary of the Zrmanja River is located in the karst area makes this system highly vulnerable and susceptible to possible anthropogenic pressures. Preservation of such and similar water systems relies on the knowledge of the main factors that govern its physical, chemical, biological and geochemical features. Due to the lack of geochemical data for the Zrmanja River estuary, a comprehensive study was carried out to explain sedimentation processes and the origin of the material within this estuary and provide additional knowledge necessary for its sustainable use and preservation. This paper, therefore, attempts to summarize the obtained data, focusing on the main natural and anthropogenic factors that define the geochemistry of the Zrmanja River estuary
Geochemical characteristics of sediments of the Novigrad sea area
Novigradsko more uvučeni je zaljev Jadranskog mora u čijem se sjeveroistočnom dijelu ulijeva rijeka Zrmanja tvoreći visokostratificirani estuarij. Istraživanje geokemijskih, sedimentoloških i mineraloških značajki sedimenata šireg područja Novigradskog mora provedeno je u svrhu određivanje podrijetla materijala, uvjeta taloženja te prirodnih i antropogenih faktora utjecaja na sedimentaciju u Novigradskom moru. Rezultati istraživanja pokazali su da je sastav recentnih sedimenata Novigradskog akvatorija određen prvenstveno prirodnim čimbenicima, iako sporadično nalazimo i utjecaj antropogenog djelovanja. Sastav istraživanih recentnih sedimenata, osim geološkom podlogom, hidrodinamskim uvjetima i biogenom produkcijom, uvjetovan je i fizikalnokemijskim procesima koji reguliraju donos otopljene i partikulatne faze rijekama Zrmanjom i Karišnicom te koagulacijom donešenog koloidnog materijala duž gradijenta saliniteta. Materijal donešen rijekom Zrmanjom dijelom se taloži na ušća rijeke u Novigradsko more dok se neistaloženi materijal u suspenziji odnosi dalje i taloži u dubljim dijelovima bazena. Reoksidacija metalnih oksida na granici voda-sediment čini sedimente Novigradskog mora mjestom odlaganja metala. Zatvorenost bazena i ograničena izmjena vode s Novigradskim morem uvjetuje u Karinskom moru pojavu suboksičnih uvjeta. Većina materijala donešena rijekama Zrmanjom i Karišnicom zadržava se na području Novigradskog i Karinskog mora. Sastav sedimenata rijeke Zrmanje upućuje na utjecaj tvornice Jadral i prijenos materijala iz njezine neposredne blizine u vodeni sustav rijeke Zrmanje vjetrom. Sastav površinskih i pridnenih voda istraživanog područja odražava geološku i hidrogeološku podlogu, dok je raspodjela u vodenom stupcu uvjetovana salinitetom i remobilizacijom elemenata iz sedimenta u vodeni stupac.Novigrad Sea is a small bay of the Adriatic Sea in which northeastern part Zrmanja River discharges and forms highly stratified estuary. Investigation of geochemical, sedimentological and mineralogical characteristics of sediments of wider area of the Novigrad Sea was conducted in order to determine the origin of the material, the deposition conditions as well as natural and anthropogenic factors of influences on sedimentation in the Novigrad Sea. The results showed that the composition of the Novigrad Sea sediments is primarily
determined by natural factors, although sporadically we find the impact of anthropogenic activities. Composition of the investigated sediments is influenced by geological background, hydrodynamic conditions, biogenic production as well as the physico-chemical processes that govern the yield of dissolved and particulate phases of the Zrmanja River and Karišnica River and coagulation of colloidal materials along the salinity gradient. Material brought by Zrmanja River partly deposits on the mouth of the river in the Novigrad Sea while the material in suspension deposits in the deeper parts of the basin. Reoxidation of metal oxides at the water-surface interface makes Novigrad Sea sediments place of trace element disposal. Most of the material brought by River Zrmanja and River Karišnica deposits within the Novigrad Sea and the Karin Sea area. The composition of the Zrmanja River sediments indicates the impact of the ex-alumina factory Jadral and transfer by wind of the material from its immediate proximity to the water system of the Zrmanja River. The composition of surface and bottom water of the Novigrad Sea area reflects the geological and hydrogeological background, while the distribution of trace elements in the water column is determined by salinity and remobilization of elements from the sediment into the water column
Osvrti: Znanstveni projekt "Transport, sudbina i toksičnost metal(oid)a otpuštenih iz ležišta industrijskog otpada (FORtIS)"
Geochemical characteristics of sediments of the Novigrad sea area
Novigradsko more uvučeni je zaljev Jadranskog mora u čijem se sjeveroistočnom dijelu ulijeva rijeka Zrmanja tvoreći visokostratificirani estuarij. Istraživanje geokemijskih, sedimentoloških i mineraloških značajki sedimenata šireg područja Novigradskog mora provedeno je u svrhu određivanje podrijetla materijala, uvjeta taloženja te prirodnih i antropogenih faktora utjecaja na sedimentaciju u Novigradskom moru. Rezultati istraživanja pokazali su da je sastav recentnih sedimenata Novigradskog akvatorija određen prvenstveno prirodnim čimbenicima, iako sporadično nalazimo i utjecaj antropogenog djelovanja. Sastav istraživanih recentnih sedimenata, osim geološkom podlogom, hidrodinamskim uvjetima i biogenom produkcijom, uvjetovan je i fizikalnokemijskim procesima koji reguliraju donos otopljene i partikulatne faze rijekama Zrmanjom i Karišnicom te koagulacijom donešenog koloidnog materijala duž gradijenta saliniteta. Materijal donešen rijekom Zrmanjom dijelom se taloži na ušća rijeke u Novigradsko more dok se neistaloženi materijal u suspenziji odnosi dalje i taloži u dubljim dijelovima bazena. Reoksidacija metalnih oksida na granici voda-sediment čini sedimente Novigradskog mora mjestom odlaganja metala. Zatvorenost bazena i ograničena izmjena vode s Novigradskim morem uvjetuje u Karinskom moru pojavu suboksičnih uvjeta. Većina materijala donešena rijekama Zrmanjom i Karišnicom zadržava se na području Novigradskog i Karinskog mora. Sastav sedimenata rijeke Zrmanje upućuje na utjecaj tvornice Jadral i prijenos materijala iz njezine neposredne blizine u vodeni sustav rijeke Zrmanje vjetrom. Sastav površinskih i pridnenih voda istraživanog područja odražava geološku i hidrogeološku podlogu, dok je raspodjela u vodenom stupcu uvjetovana salinitetom i remobilizacijom elemenata iz sedimenta u vodeni stupac.Novigrad Sea is a small bay of the Adriatic Sea in which northeastern part Zrmanja River discharges and forms highly stratified estuary. Investigation of geochemical, sedimentological and mineralogical characteristics of sediments of wider area of the Novigrad Sea was conducted in order to determine the origin of the material, the deposition conditions as well as natural and anthropogenic factors of influences on sedimentation in the Novigrad Sea. The results showed that the composition of the Novigrad Sea sediments is primarily
determined by natural factors, although sporadically we find the impact of anthropogenic activities. Composition of the investigated sediments is influenced by geological background, hydrodynamic conditions, biogenic production as well as the physico-chemical processes that govern the yield of dissolved and particulate phases of the Zrmanja River and Karišnica River and coagulation of colloidal materials along the salinity gradient. Material brought by Zrmanja River partly deposits on the mouth of the river in the Novigrad Sea while the material in suspension deposits in the deeper parts of the basin. Reoxidation of metal oxides at the water-surface interface makes Novigrad Sea sediments place of trace element disposal. Most of the material brought by River Zrmanja and River Karišnica deposits within the Novigrad Sea and the Karin Sea area. The composition of the Zrmanja River sediments indicates the impact of the ex-alumina factory Jadral and transfer by wind of the material from its immediate proximity to the water system of the Zrmanja River. The composition of surface and bottom water of the Novigrad Sea area reflects the geological and hydrogeological background, while the distribution of trace elements in the water column is determined by salinity and remobilization of elements from the sediment into the water column
Can multiple fish farms be integrated within a semi-enclosed bay without causing acute ecosystem degradation?
The current study explores the possibility that multiple fish farms (FFs) containing sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) can be successfuly integrated within a semi enclosed bay in the Croatian Adriatic. The research focuses on determining principal environmental factors (EFs) that control the integration and atempts to estimate their individual and synergic ability to influence deposition and removal of organic matter (OM) and trace elements (TE) from the system. The complexity of the designated tasks demanded a comprehensive number of various datasets and samples to be used in the analysis. The ADCP data revealed strong wind induced currents forming within the research domain resulting in high system flushing efficiency (3.5 – 6 days). The sediment samples from all stations contained relatively inert minerals which contributed to overall low OM and TE concentrations and very limited variability found across the entire bathymetric range. The thermal advection effect recorded at two stations was attributed to specific seabed topography and the hydrodynamic response formed during Maestral wind episodes. The results indicate that a successful integration of four FFs has taken place within the research site (semi enclosed bay), and that the key EFs responsible for its success are strong wind induced hydrodynamics, favorable seabed topography and sediment mineral composition. The synergy of the principal EFs that formed within the system was found to have an attenuating effect regarding FFs chemical influence (OM and TE) and an amplifying one regarding spatial footprint which extended to ≈ 2000 m distance
APPLICATION OF ECOLOGICAL ENGINEERING IN LANDFILL REMEDIATION
Ecological engineering is a new branch of engineering based on ecology that emerged in the 1960s from the growing need for more sustainable biological solutions to
environmental problems. It is based on the design of natural ecosystems for the benefit of both nature and human society, and its techniques can be applied to a range of environmental problems, from the restoration of degraded ecosystems to the removal of pollutants. One of the major environmental problems worldwide is waste disposal in the form of landfills, with its various negative impacts on the environment, living beings and human health. Conventional landfill closure and remediation techniques have proven to be economically and energetically challenging and are not sufficiently effective in reducing leachate formation and removing pollutants. For this reason, this article presents
several ecological engineering techniques that can be used in landfill remediation. Phytocapping is an alternative to conventional cover systems that uses plants to control and limit water infiltration into waste, leachate formation, stabilize landfills, control erosion, and reduce methane emissions. Phytoremediation is an environmentally friendly technology for soil remediation through natural processes, in two forms: phytoextraction and phytostabilization. Phytoextraction uses plants to extract and remove pollutants from waste and soil, while phytostabilization is used to immobilize pollutants in the root zone. Constructed wetlands, designed and constructed according to the principles of natural wetland ecosystems, can be used to clean leachate. Natural attenuation uses natural biological processes to mitigate pollution without taking specific action. All of these
techniques are based on viable natural solutions that can reduce remediation costs and further maintenance of the landfill. Although they are increasingly being considered in developed countries, there are few examples of their application in landfill remediation in Croatia
Geochemical Equilibrium and Processes in Seawater
The geochemical equilibrium in the seawater must be observed taking into account the chemical, geological as well as biological processes. Namely, the concept of equilibrium takes into account the composition of the system and the kinetics of the reactions taking place therein. In coastal waters, nutrients and trace elements can be delivered not only through rivers but also through atmospheric input and submarine groundwater discharges. In addition to natural sources, levels of different elements can also be influenced by growing and diverse human activities along the coasts. Consequently, the pathways and fate of different environmental chemicals in coastal areas are governed by various factors. The multiparameter approach, combined with different statistical tools, is a well-established way of interpreting their inputs and behaviour in marine systems. Nevertheless, the data for the karst regions, as found in the Mediterranean, are particularly scarce. The Special Issue “Geochemical Equilibrium and Processes in Seawater” of Geosciences gathers five articles on different topics related to water and sediment geochemistry of the coastal karst areas of the Mediterranean, including Slovenia, Croatia and Egypt. The topics included by this Issue refer to 1) geochemistry of sediments in the area of intensive anthropogenic activity, 2) the geochemistry of sediment and biota in protected area under increasing pressure due to tourist activity, 3) the influence of thermal power plant on the geochemistry of the surrounding area, 4) the influence of underground water discharges on the water quality, and 5) the possibility of monitoring natural and anthropogenic processes in karst systems by using a specific group of elements
Distribution of rare earth elements in citrus leaves and reference materials (NIST SRM 1515 and ERM CD281)
The present study aims to discuss the data on levels and distribution of rare earth elements, including Y, (REYs) in leaves of three different citrus species (lemon, orange, and tangerine) and provide additional information about the major, minor and trace elements in two biological certified reference materials (CRMs), Apple leave (NIST SRM 1515) and Rye grass (ERM CD281). In all samples, element concentrations were determined by High Resolution Inductively Coupled Plasma Mass Spectrometry. The obtained data display substantial variability in the distribution of REY elements, not only between different citrus species but also between different genera of plants indicating their different uptake and accumulation abilities. Measured concentrations of REYs in citrus leaves were substantially lower compared to the literature values, although the fractionation indices were comparable. The data for CRMs provide additional information for the 14 elements in NIST SRM 1515 and the 30 elements in ERM CD281, including rare earth elements
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