From spatial models to spatial evaluation in the analysis of wetland restoration in the Vecht river basin

Water tables are strictly controlled throughout much of the Netherlands. Higher water tables could permit the restoration of wetland ecosystems. Deriving benefits from this requires the spatial matching of physical planning, eco-hydrological processes, and economic activities. This paper reports on a study combining spatial analysis and disciplinary integration to assess management strategies for the Vecht river basin in the Netherlands. The paper addresses two research questions. How can the information generated by spatial models be condensed into performance indicators for the evaluation of strategies? How can spatial information be retained in the evaluation, and does this lead to different rankings and/or insights? Procedures for the construction of performance indicators for three criteria – net present value, environmental quality and spatial equity – are presented. The evaluation concludes that recreation and higher water tables provide a means for restoration, recouping of costs, and stimulating regional incomes. Maintenance of spatial detail led to different insights, and in particular indicated uncertainty about this conclusion.     

Interaction of marine sediment with DNA and DNA availability to nucleases

A method for the determination of DNA in sediments is described. The comparison between DNA extraction profiles from natural sediment samples and from precleaned sediments (concentrated nitric acid and subsequently 1 100 °C), to which known amounts of DNA were added, demonstrates that the sand particles participate in the delay of extraction of DNA we observed. Experiments with nuclease mixtures show that DNA by its interaction with the sediment is protected considerably against degradation by nucleases.     

Influence of ultraviolet-radiation on chlorophyll fluorescence and growth in different life-history stages of three species of Laminaria (phaeophyta)

Zoospores, gametophytes, young sporophytes and discs cut from mature sporophytes of Laminaria digitata, L. hyperborea and L. saccharina were exposed in the laboratory to UV-radiation, with a spectral composition and irradiance similar to natural sunlight, for periods ranging from 15 min to 8 d, and were then returned to white light. Germination of zoospores and the growth of gametophytes were reduced after exposures to UV longer than 1 h, whereas UV had little effect on the growth of young or mature sporophytes unless exposure continued for more than 48 h. The variable fluorescence (F _v:F_m) of all stages was strongly reduced immediately after short exposures to UV, but recovered almost completely within 24 h. However, exposure of gametophytes to UV for >4 h resulted in little or no recovery of F _v:F_m, whereas >16 h of UV were required to produce this result in young sporophytes, and >48 h in mature sporophytes. Thus, sensitivity to UV-radiation decreased from gametophytes to sporophytes, and with increasing age of sporophytes, but, in gametophytes, growth appeared to be a more sensitive indicator of UV-damage than F _v:F_m after 24 h recovery. The responses to UV of the zoospores and gametophytes of all three species were similar, but both growth and fluorescence measurements suggested that the sporophytes of L. saccharina were more sensitive to UV than those of the other two species.     

Current EU-27 technical potential of organic waste streams for biogas and energy production

Anaerobic digestion of organic waste generated by households, businesses, agriculture, and industry is an important approach as method of waste treatment – especially with regard to its potential as an alternative energy source and its cost-effectiveness. Separate collection of biowaste from households or vegetal waste from public green spaces is already established in some EU-27 countries. The material recovery in composting plants is common for biowaste and vegetal waste. Brewery waste fractions generated by beer production are often used for animal feeding after a suitable preparation. Waste streams from paper industry generated by pulp and paper production such as black liquor or paper sludge are often highly contaminated with toxic substances. Recovery of chemicals and the use in thermal processes like incineration, pyrolysis, and gasification are typical utilization paths. The current utilization of organic waste from households and institutions (without agricultural waste) was investigated for EU-27 countries with Germany as an in-depth example. Besides of biowaste little is known about the suitability of waste streams from brewery and paper industry for anaerobic digestion. Therefore, an evaluation of the most important biogas process parameters for different substrates was carried out, in order to calculate the biogas utilization potential of these waste quantities. Furthermore, a calculation of biogas energy potentials was carried out for defined waste fractions which are most suitable for anaerobic digestion. Up to 1% of the primary energy demand can be covered by the calculated total biogas energy potential. By using a “best-practice-scenario” for separately collected biowaste, the coverage of primary energy demand may be increased above 2% for several countries. By using sector-specific waste streams, for example the German paper industry could cover up to 4.7% and the German brewery industry up to 71.2% of its total energy demand.