Salinity variations in the northern Coorong Lagoon, South Australia: Significant changes in the ecosystem following human alteration to the natural water regime

European settlement and drought have significantly impacted the hydrology of the Coorong, a shallow coastal lagoon complex in South Australia, which is part of a terminal wetland at the mouth of the River Murray. An increased salinity associated with lower water levels and progressive isolation from ocean flushes contributed to a severe decline in ecological diversity over the past decades. Here we have conducted a molecular and stable isotopic study of a sedimentary core from the northern Coorong Lagoon spanning more than 5000 years to investigate the recent palaeoenvironmental history of the ecosystem. Major alterations were evident in many biogeochemical parameters in sediments deposited after the 1950s coinciding with the beginning of intensified water regulations. The most prominent shift occurred in δ13C profiles of C21–C33n-alkanes from average values of −23.5‰ to an average of −28.2‰.Further changes included decreases in carbon preference index (CPI) and average chain length (ACL) of the n-alkane series as well as significant increases in algal (e.g. C20 HBI, long chain alkenes and C29-alkadiene) and bacterial (e.g. 13C depleted short chain n-alkanes and hopanoids, δ13C: −35.9‰ to −30.1‰) derived hydrocarbons. Long chain n-alkanes with a strong odd/even predominance as observed here are typically attributed to terrigenous plants. In the Coorong however, terrigenous input to sedimentary OM is only minor. Therefore changes in the before mentioned parameters were attributed to a source transition from a major contribution of macrophytes towards predominantly microalgae and bacteria.δD values of C21–C33n-alkanes showed a general trend towards more enriched values in younger sediments, indicating an overall rising salinity. However, the most pronounced positive shift in these profiles again occurred after the 1950s. Altogether this study demonstrates that the recent human induced changes of the Coorong hydrology, compounded by a severe drought led to an increase in salinity and alterations of primary production which have been much more significant than natural variations occurring throughout the Holocene over several thousands of years

The Influence of Compounds from Selected Higher Plant Taxons on Platelet Aggregation

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department: Pharmaceutical Botany and Ecology Candidate: Mgr. Eliška ŠTEJNAROVÁ Supervisor: Doc. RNDr. Lubomír OPLETAL, CSc. Title of doctoral thesis: The Influence of Compounds from Selected Higher Plant Taxons on Platelet Aggregation As a part of phytochemical study of secondary metabolites of plants from family Asteraceae, 32 species from this taxonomical unit were tested for platelet aggregation and antioxidant activity. Platelet aggregation was evaluated in vitro on human thrombocytes in platelet rich plasma. The primary used concentration of extracts was 500 µg·mL-1 , arachidonic acid (AA), adenosine diphosphate (ADP), collagen (COL), and thrombin (TR) were used as agonists. Out of the tested species, Leuzea carthamoides (leaves) was the only species which exhibited antiplatelet activity, the extract inhibited platelet aggregation induced by ADP and COL by 33 ± 6 % and 95 ± 5 %, respectively. None of the tested taxons showed proaggregatory effect. From 10.5 kg of dried leaves of L. carthamoide the extracts were prepared sequentially; five compounds: LC-1 (cynaropicrine), LC-2 (chlorojanerin), LC-3 (repdiolid), LC-4 (jaceosidin), LC-5 (hispidulin) were isolated from the most active extract (chloroform) by column and thin layer..

The Fair Participation of the Companies Producing the Machines for Agriculture within European Union Market

The diploma thesis is dealing with the assessment of the strategy for the fair participation of the companies producing machines for the feed production within the EU market. There is aimed on the agricultural production industry and the companies' performance with the competitors on the EU market are compared. As the fractional objectives were included the characteristics of the company ROmiLL Ltd., elaboration of market segmentation, the concept of the fairs and exhibitions, where the company regularly takes part, analysis of the environment in which this company exists. Because I am dealing with the topic of agricultural production, in the present thesis is analysed one of the shared politics of the European Union - The Common Agricultural Policy. One of the main results of the thesis is the proposed strategy of the company that will improve the company's position in the market with regard to the fractional goals. The marketing recommendations for the industry at the time of economic crisis were designed

Atmospheric Short-Chain Chlorinated Paraffins in China, Japan, and South Korea

This study presents the first investigation of concentrations and congener group patterns of atmospheric short-chain chlorinated paraffins (SCCPs) throughout East Asia. Based on an absorption rate calibration experiment, a spatial survey of SCCPs was performed using passive air samplers in China, Japan, and South Korea during two separate periods in 2008. The atmospheric concentrations of SCCPs in China were clearly greater than those in Japan and South Korea, both of which exceed the levels determined for other regions of the world. C-10 components were the most abundant type of SCCPs in China, whereas C-11 components were dominant in Japan and South Korea. With respect to the total chlorine content, Cl-6 and Cl-5 were the predominant compounds in China and Japan; however, Cl-6 and Cl-7 were predominant in South Korea. A similar pattern was also found for remote sites within China, Japan, and South Korea, respectively. Together with the back-trajectories calculated for the remote sites, the results indicate that the SCCPs in the air of East Asia were mainly influenced by local sources due to their relatively low long-range atmospheric transport potential compared to other POPs.This study presents the first investigation of concentrations and congener group patterns of atmospheric short-chain chlorinated paraffins (SCCPs) throughout East Asia. Based on an absorption rate calibration experiment, a spatial survey of SCCPs was performed using passive air samplers in China, Japan, and South Korea during two separate periods in 2008. The atmospheric concentrations of SCCPs in China were clearly greater than those in Japan and South Korea, both of which exceed the levels determined for other regions of the world. C-10 components were the most abundant type of SCCPs in China, whereas C-11 components were dominant in Japan and South Korea. With respect to the total chlorine content, Cl-6 and Cl-5 were the predominant compounds in China and Japan; however, Cl-6 and Cl-7 were predominant in South Korea. A similar pattern was also found for remote sites within China, Japan, and South Korea, respectively. Together with the back-trajectories calculated for the remote sites, the results indicate that the SCCPs in the air of East Asia were mainly influenced by local sources due to their relatively low long-range atmospheric transport potential compared to other POPs