Ecoregions in the Southern Balkans: Should Their Boundaries Be Revised?

Ecoregion delineations have gained increased attention in Europe, especially following the Water Framework Directive 2000/60/EC (WFD), which provides the European Union’s first policy-relevant ecoregion map. However, the WFD’s ecoregions were created through a minor adaptation of Illies’ (Limnofauna Europaea. Gustav Fisher Verlag, Stuttgart, 1967/1978) freshwater zoogeographic regions, and the map’s specific boundaries have not been widely evaluated with respect to the WFD’s uses or their biogeographic accuracy. We examined the WFD ecoregion boundaries in Greece and its neighboring Balkan states by comparing them with the most prominent freshwater biogeographic boundaries as shown by riverine freshwater fish assemblages. Classification and ordination analyses of 23 river basin fish assemblages helped delineate natural faunal break boundaries in freshwater species assemblage distributions depicting major biogeographic barriers to aquatic biota dispersal. However, these biogeographic boundaries differ from those delineated in the WFD map, suggesting boundary errors and inconsistencies in the delineation method of the WFD ecoregions. We reviewed specific boundary disagreements and produced a map showing the region’s most prominent freshwater biogeographic boundaries by charting them on watershed borders among the four biotically dissimilar river basin groups in the southern Balkans. This regional evaluation reveals both a need to reconcile disparate approaches to ecoregion mapping and to promote the development of a new policy-relevant inland waters ecoregion framework that would support broad-scale water management and aquatic conservation.     

Bioenergy to save the world

BACKGROUND AND AIM: Following to the 2006 climate summit, the European Union formally set the goal of limiting global warming to 2 degrees Celsius. But even today, climate change is already affecting people and ecosystems. Examples are melting glaciers and polar ice, reports about thawing permafrost areas, dying coral reefs, rising sea levels, changing ecosystems and fatal heat periods. Within the last 150 years, CO2 levels rose from 280 ppm to currently over 400 ppm. If we continue on our present course, CO2 equivalent levels could approach 600 ppm by 2035. However, if CO2 levels are not stabilized at the 450-550 ppm level, the consequences could be quite severe. Hence, if we do not act now, the opportunity to stabilise at even 550 ppm is likely to slip away. Long-term stabilisation will require that CO2 emissions ultimately be reduced to more than 80% below current levels. This will require major changes in how we operate. RESULTS: Reducing greenhouse gases from burning fossil fuels seems to be the most promising approach to counterbalance the dramatic climate changes we would face in the near future. It is clear since the Kyoto protocol that the availability of fossil carbon resources will not match our future requirements. Furthermore, the distribution of fossil carbon sources around the globe makes them an even less reliable source in the future. We propose to screen crop and non-crop species for high biomass production and good survival on marginal soils as well as to produce mutants from the same species by chemical mutagenesis or related methods. These plants, when grown in adequate crop rotation, will provide local farming communities with biomass for the fermentation in decentralized biogas reactors, and the resulting nitrogen rich manure can be distributed on the fields to improve the soil. DISCUSSION: Such an approach will open new economic perspectives to small farmers, and provide a clever way to self sufficient and sustainable rural development. Together with the present economic reality, where energy and raw material prices have drastically increased over the last decade, they necessitate the development and the establishment of alternative concepts. CONCLUSIONS: Biotechnology is available to apply fast breeding to promising energy plant species. It is important that our valuable arable land is preserved for agriculture. The opportunity to switch from low-income agriculture to biogas production may convince small farmers to adhere to their business and by that preserve the identity of rural communities. PERSPECTIVES: Overall, biogas is a promising alternative for the future, because its resource base is widely available, and single farms or small local cooperatives might start biogas plant operation.     

Sediment and Suspended Matter Lead Contamination in the Gulf of Kavala, Greece

Sediment and suspended particulate matter samples from 24 stations in the Gulf of Kavala have been examined for lead contamination. Grain size analysis and organic matter content were also performed. Total – anthropogenic sediment lead concentrations and enrichment factors at stations close to harbors and chemical industries were found higher (up to 209–135μg/g and 4.12 respectively), in relation to concentrations from the rest of the coastal zone. In the above areas, increased suspended particulate lead in the bottom of the water column was also recorded (up to 109μg/g). Total sediment lead concentrations composed of high natural Pb background increased with decreasing grain size, suggesting their association with the fine fractions of the sediments (31.1–66.0% mud presence) and the organic matter content (6–9% higher values). Overall, higher total lead concentrations in the sediments, determined by this work, appear to be significantly different from those reported for the Gulf of Kavala in previous studies and similar to those detected in other highly contaminated eastern Mediterranean coastal areas.     

Development of a total Ash Quality Index and an Ash Quality Label: Comparative analysis of slagging/fouling potential of solid biofuels

Environmental Science and Pollution Research - Biomass combustion generates considerable amounts of ash that are related to slagging/fouling problems in combustors. Numerous indices have been...     

Weed mapping in cotton using ground-based sensors and GIS

Site-specific weed management presupposes the careful monitoring and mapping of weed infestation areas. Cut-edge sensor technologies coupled with geographical information systems (GIS) provide the means for reliable decision-making concerning weed management even in sub-field level. In present research, two different spectral sensing systems were engaged in order to digitally map weed patches as grown in four different cotton fields in Central Greece. The systems used were a set of two Crop Circle multispectral sensors ACS-430 and a digital camera Nikon D300S. The spaces between cotton rows were scanned and photographed with the two systems accordingly. Raw recorded data were stored and analyzed in GIS environment producing spatially interpolated maps of red-edge normalized difference vegetation index (NDVI) and weed cover percentage values. Both mapping approaches were satisfactorily related to weed distribution as occurred in the fields; however, the photographic method tended to underestimate weed populations. Correlation of red-edge NDVI and weed cover values, at the points where photographs were taken, as revealed by Pearson’s correlation coefficient was high (r?>?0.83) and statistically significant at the 0.01 level. A first-degree linear equation adequately modeled (R²?>?0.7) the between value pair relations, strengthening the validity of the two methodologies in spatially monitoring weed patches. The methodologies and the technologies used in the study can be used for yearly mapping weed flora in cotton cultivation and potentially constitute a means of rationalizing herbicide application in terms of doses and spatio-temporal decision-making.     

Oxidative stress in Cyprinus carpio to analyze microcystin impact in eutrophic shallow lakes: a preliminary study

Microcystins (MCYSTs) are toxins produced by cyanobacteria in aquatic environment and are of high potential risk to aquatic organisms. The physiological responses and pathobiological developments that they elicit in fish have been extensively studied, mainly through acute toxicity experiments. This study was designed to examine the seasonal fluctuation of biochemical markers of oxidative stress in different tissues of a natural population of Cyprinus carpio inhabiting a shallow Mediterranean lake, along with the respective MCYSTs concentrations in blood and tissues at environmentally relevant MCYSTs values. MCYSTs content was assessed in liver, kidney, intestine, brain and muscle along with the MCYSTs in lake water and scum applying ELISA technique. Catalase activity, GSH/GSSH relative concentrations and lipid peroxidation were used as biochemical markers. Our results suggest that common carp of Lake Pamvotis exposed to naturally fluctuating concentrations of MCYST in water and scum contained stably high MCYST concentrations in all tissues that might pose a threat to public health. Liver and kidney were the primary target organs. Tissue concentrations did not correlate with the response of any of the elements of the antioxidant defence system. Hepatic catalase, GSH content and TBARS in all tissues tested followed the fluctuations of major limnological parameters, i.e. water temperature and oxygen concentration, chlorophyll-a, MCYST in water and scum, suggesting that they should be cautiously used to monitor exposure to MCYSTS in natural freshwater ecosystems.     

Organochlorine and mercury contamination in fish tissues from the River Nestos, Greece

Polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) isomers, dichlorodiphenyltrichloroethane (DDT) and its metabolites, other organochlorine pesticides such as hexachlorobenzene (HCB), chlordane compounds (CHLs, including trans-chlordane and cis- and trans-nonachlor) and the heavy metal mercury were quantified in muscle and liver of the European chub (Leuciscus cephalus, Linnaeus, 1758) and in the muscle of the barbel (Barbus cyclolepis, Heckel, 1837) at two sampling sites of the River Nestos, Greece. PCBs in muscle and DDTs in the liver tissues were the predominant organochlorinated contaminants. Among the PCBs, congeners 47 (up to 9.60 ng g(-1) wet wt.), 180 (up to 1.15 ng g(-1) wet wt.) and 190 (up to 1.50 ng g(-1) wet wt.) were the most frequent and abundant. The contamination degree by the sum of PCBs on the fish tissue samples from the River Nestos is lower or similar to PCB levels found in other ecosystems. Among the organochlorine pesticides, essentially only p,p'-DDD, p,p'-DDE and alpha-, beta- and gamma-HCH were found, with the former appearing at mean levels up to 30.71 ng g(-1) wet wt. From a public health standpoint, residue organochlorine pesticide levels from our work are considerably lower than the recommended tolerance limits. Finally, mean values of Hg in chub were significant lower (up to 31.04 ng g(-1) wet wt.) compared to those detected on barbel (up to 169.27 ng g(-1) wet wt.). The concentrations of Hg in fresh water fish from the River Nestos did not exceed WHO and US EPA health guidelines, and were suitable for human consumption.