Eighty-year review of the evolution of landscape ecology: from a spatial planning perspective

Landscape Ecology - Sustainable spatial development requires the establishment of a balance between rational land use and the protection of nature, ecosystems and biodiversity on various spatial...     

Dependence of the common carp (Cyprinus carpio L.) fatty acid profile on diet composition in a semi‐intensive farming system: tissue and time variability

Increasing the amount of n‐3 PUFA in carp meat is one of the most important tasks in enhancing its overall quality. However, the relative influence of supplemental feed and natural feed on the FA profile of cultivated carp flesh is not well documented, making it difficult to choose the most efficient strategy. Carp diet composition and diet and flesh fatty acid profiles were simultaneously followed in order to determine the influence of pelleted feed compared to natural feed on fatty acid profiles of carp tissues. Pelleted feed clearly dominated over zooplankton and Chironomidae in the carp diet, producing carp tissue fatty acid profiles closely resembling those of pelleted feed. However, increase in the abundance of zooplankton over the course of the investigation resulting in concomitant increase of its proportion in feed bulk was in strong positive correlation with increase in n‐3 HUFA in the dorsal muscle. n‐3 PUFA enrichment of supplemental feed could be the dominant mechanism in production of carp meat rich in n‐3 PUFA. However, even a small increase in natural feed availability could significantly change the diet of common carp and result in considerable improvement of meat quality with regard to n‐3 HUFA content.     

Effects of cage fish farming on phytoplankton community structure,biomass and primary production in an aquaculture area in the middle Adriatic Sea

In this study, we investigated the physical, chemical and biological parameters of the water column at two stations under different trophic conditions during a 1‐year period (from September 2005 to September 2006) in an aquaculture area. The investigation was performed monthly at a station inside the fish farm in Maslinova Bay (middle Adriatic Sea, Croatia) and at a control station located in the Hvar Channel in the vicinity of the farm. The results showed that the concentrations of dissolved nutrients were slightly enhanced at the farm station in comparison with the control station, although those differences were not statistically significant, nor were the differences in oxygen saturation recorded during the investigation period. As opposed to the chemical parameters, considerably higher deviations were recorded for biological parameters as demonstrated by a significant increase in phytoplankton biomass and primary production (measured in situ) at the farm station, particularly during the summer season. Phytoplankton community structure analysis showed that the phytoplankton composition at the farm was mostly determined by seasonal changes rather than by the influence of fish farming. In Maslinova Bay, no causal links were identified between increased biomass and the appearance of toxic species.     

The Effect of Thermal Treatment Method on Fatty Acid Composition in Northern Pike (Esox lucius) Fillets

The aim of the present study was to investigate the effect of thermal treatment methods, such as microwave cooking, steaming, and shallow pan-frying on fatty acids composition in northern pike fillets. All methods of thermal treatment increased fat content in the fillets. Microwave cooking decreased the proportion of saturated fatty acids and increased the proportion of total, n-3, and n-6 polyunsaturated fatty acids as compared with fresh fillets. Steam cooking did not affect the proportion of saturated, monounsaturated, and polyunsaturated fatty acids, whereas pan-frying significantly increased the proportion of monounsaturated and n-6 polyunsaturated fatty acids. All cooked fillets, regardless of the thermal treatment used, had acceptable n–6/n–3 ratio; however, microwave cooking enabled fish products to obtain more beneficial n-6/n-3 ratio than frying. Due to high polyunsaturated fatty acids content and low n-6/n-3 ratio, microwave cooking may be recommended for preparing wild pike fillets in households.     

Influence of cytokinins on in vitro morphogenesis in root cultures of Centaurium erythraea—Valuable medicinal plant

The purpose of this work was to acquire more information on the capacity of in vitro grown Centaurium erythraea Gillib. normal and hairy root cultures to simultaneously regenerate adventitious buds and to evaluate the variations induced on regeneration response by treatments with six cytokinins. Explants from normal and hairy root cultures were cultured on half-strength MS medium (1/2 MS) with kinetin (KIN), N⁶-benzylaminopurine (BA), 6-γ,γ-dimethylallylaminopurine (2IP), N-(2-chloro-4-pyridyl)-N′-phenylurea (CPPU), 1-Phenyl-3-(1,2,3-thiadiazol-5-yl)urea (TDZ) and 6-[4-Hydroxy-3-methyl-but-2-enylamino]purine (ZEA), used alone in six different concentrations. The average number of adventitious buds per explant was promoted by all of cytokinin treatments. Urea-type cytokinins, TDZ and CPPU were more effective for the induction the morphogenesis of adventitious buds than adenine-type cytokinins. We found that the 1.0 μM CPPU induced the largest number (25.6, 18.2, respectively) of adventitious buds in normal and hairy root culture. TDZ-supplemented media induced highest number of adventitious buds (24.2) from normal root explant, but from hairy root explant average number of buds is lower (20.5). Regenerated shoots were excised and placed on 1/2 MS medium without hormone. The rooted plantlets were successfully acclimatized in greenhouse conditions.     

Biotechnological Enhancement of Probiotics through Co-Cultivation with Algae: Future or a Trend?

The diversity of algal species is a rich source of many different bioactive metabolites. The compounds extracted from algal biomass have various beneficial effects on health. Recently, co-culture systems between microalgae and bacteria have emerged as an interesting solution that can reduce the high contamination risk associated with axenic cultures and, consequently, increase biomass yield and synthesis of active compounds. Probiotic microorganisms also have numerous positive effects on various aspects of health and represent potent co-culture partners. Most studies consider algae as prebiotics that serve as enhancers of probiotics performance. However, the extreme diversity of algal organisms and their ability to produce a plethora of metabolites are leading to new experimental designs in which these organisms are cultivated together to derive maximum benefit from their synergistic interactions. The future success of these studies depends on the precise experimental design of these complex systems. In the last decade, the development of high-throughput approaches has enabled a deeper understanding of global changes in response to interspecies interactions. Several studies have shown that the addition of algae, along with probiotics, can influence the microbiota, and improve gut health and overall yield in fish, shrimp, and mussels aquaculture. In the future, such findings can be further explored and implemented for use as dietary supplements for humans.     

Editorial

Skadar Lake, a large, shallow, subtropical lake on the Albanian frontier in south-western Yugoslavia, supports a commercial fishery which annually yields nearly a thousand metric tons. Examination of catch statistics plus documentation of increasing effort during 1947 through 1973 reveals a declining catch per unit of effort. Water quality has not changed since 1952. However, changes in gear, effort, and exploitation have apparently caused major shifts in species composition and size of the catch. Rapid technological changes in gear coupled with potential environmental degradation may lead to decreased stocks and over-exploitation. Only by instituting a comprehensive management programme, within the context of international cooperation and sound ecological information, can a high sustained yield be maintained and over-exploitation of commercially important fish stocks in Skadar Lake be presented.