Funktionalität der getesteten flussbaulichen Maßnahmen im Pilotprojekt Bad Deutsch-Altenburg

A comprehensive monitoring program was compiled in order to observe all measures at the Danube River within the pilot project Bad Deutsch-Altenburg also during the implementation phase. Especially bathymetry analyses, Freeze Core samples and pebble tracers provided insights into the functionality of the measure “granulometric bed improvement (GBI)”. Furthermore the monitoring showed first reactions regarding the reconstruction of the low flow river regulation and the reconnection of the Johler sidearm.     

SED_AT – Feststoffhaushalt,Sedimenttransport und Flussmorphologie im Rahmen des Nationalen Gewässerbewirtschaftungsplans

According to the National River Basin Management Plan, more than 50?% of the rivers investigated are at risk of failing to attain a good ecological status or good ecological potential by 2015, mainly due to hydromorphological impacts. These impacts are closely connected to problems resulting from changes in the sediment regime, sediment transport and river morphology. Within the scope of the SED_AT project, existing problems within this context were evaluated by means of stakeholder surveys, a literature review and expert assessments. In turn, the results were used to derive and define the future steps that need to be taken (in terms of research, management, and legal concerns). The project findings clearly show that within each of the sectors considered (Austrian Service for Torrent and Avalanche Control, river engineering, ecology, hydropower, waterways, and agriculture) changes in the sediment regime, sediment transport and river morphology are causing problems, and that there is a need for action with regard to improved sediment management, e.g. the development of catchment-specific sediment management concepts, but also concerning the optimization of structures relevant to sediment continuity. The data gathered also indicates that working together to address these challenges (more than 88?% of the mutual needs analyses resulted in either agreement or no conflicts) can produce meaningful synergies for all sectors. This paper outlines the SED_AT project and presents its key findings, both with regard to the problem assessments for the respective sectors and to the need for integrative, concerted action.     

Nährstoffflüsse in Uganda: Eine Fallstudie aus dem Busia District

While the population of Uganda is steadily rising, the nutrient balances in local agricultural soils are deteriorating. This work demonstrates the quantitative potentials that various nutrient flows hold to compensate for this negative development. In the course of our case study, material flow analyses for the nutrients nitrogen, phosphorus and potassium were conducted in the Busia District of eastern Uganda. Though the results confirm the negative nutrient balances in agricultural soils, they also indicate that reducing erosion and leaching, introducing crop and field rotation, and more effectively employing farm fertilizers have the best chances of improving the situation. The last-mentioned aspect can also include the use of human waste as fertilizer, although hygienic considerations are an obstacle. In contrast, approaches involving municipal, fruit and vegetable waste from urban areas are less effective but can be relatively quickly implemented, as the current practice shows.     

“不是N的N”格式研究

现代汉语语法中不是N的N是一种特殊的构式,但已有的研究大多是从单一的角度分析变量的语义或者是构式义,尚未对其进行多角度的分析。尝试运用认知语言学中的构式理论,采用描写和解释相结合的方法,对这个结构进行多角度分析,旨在深化对汉语中这种新型表达式的认识。     

Hochwasserrückhalteanlagen im Südburgenland

In Southern Burgenland, located in southeast Austria, the annual precipitation amounts to roughly 800 mm; when heavy rains hit, daily precipitation maxima can be as high as 100 mm. These extreme precipitation events in the middle basin of the Rába (Raab) River produce not only extremely high, concentrated peak discharge values, but also flood waves with considerable transport loads. So as to avoid flood damages, above all preventive measures in the form of flood retention structures are implemented as close to the at-risk settlements as possible.     

ÖKOHYDRAULIK – Integrative Methoden in Wissenschaft und Praxis im Spannungsfeld der europäischen Richtlinien (Hochwasser-, Wasserrahmen- und Erneuerbare Energie)

The requirements and objectives of those European guidelines that are most relevant for Austrian water management reflect at times disparate perspectives with regard to the current and future use of our waters. In some cases the objectives are in fact diametrically opposed (Renewables Directive and Water Framework Directive), while in others there is the potential for synergies, for example the call for providing more space for rivers (Floods Directive and Water Framework Directive). These potentials for conflict and desirable synergies underline the need to adopt increasingly interdisciplinary approaches, and to translate those approaches into concrete projects. With the help of ecohydraulics, an interdisciplinary field combining hydraulics, river morphology and aquatic biology (as well as vegetation), it is possible to address precisely this need for an integrative perspective, both in fundamental research and in water management practice. With regard to its implementation in river engineering projects, especially habitat modeling approaches concerning different spatial scales allow to assess the varying habitat needs of specific indicator species (macrozoobenthos and fish) in a quantitative and objective way. These methods for quantifying potential habitat changes, e.g. as a water diversion, offer an essential foundation for responding to current and future water management issues.     

Einfluss unterschiedlicher Rotteparameter auf die N2O-Freisetzung während der Bioabfallkompostierung – erste Erkenntnisse aus Laborversuchen mit kontinuierlicher Lachgasmessung

During the biological treatment of organic waste nitrous oxide and methane are generated, both greenhouse gases. An increase in separate collection together with a ban to landfill organic waste has led to a significant increase in the amount of organic waste undergoing treatment in recent years. Thus, also greenhouse gas emissions from mechanical-biological treatment and composting increased significantly. However, currently the underlying mechanisms for the formation of nitrous oxide emissions are not yet fully understood. Therefore, composting experiments at laboratory scale aimed at identifying conditions under which nitrous oxide emissions are minimized. For this, new innovative measurement methods are used, such as laser absorption spectroscopy for the continuous quantification of nitrous oxide. It was found that a continuous monitoring of processes is crucial, since the formation and release of nitrous oxide is very sensitive to changes in the environment (e.g. air/oxygen supply, C/N ratio of the input material, pH) and occurs very heterogeneously during the composting progress. In this paper the influence of the variations of the pH value of the input material and the amount of aeration is exemplified. It was shown, that under specific environmental conditions the technical composting process may even act as a “sink” for atmospheric N₂O.     

Verwertung organischer Reststoffe in Faulbehältern kommunaler Kläranlagen

Meanwhile, the long-term practical experience and the scientific research results about the utilisation of organic residues in heated sludge digesters of municipal wastewater treatment plants are sufficient for an interim résumé about co-digestion and for recommendations for the practical approach. In this paper, effects, backlashes and consequences of the co-digestion of organic substrates are described in detail. Concerning the stability of the digestion process and the expected production of digestion residues, co-digestion has proved to exhibit positive effects. Problems might occur regarding the additional nitrogen loads in the reject water from sludge treatment as well as with regard to the enrichment of impurities in the sludge digesters—in particular in the case of the use of food leftovers from restaurants and so-called bio-waste from households. Additional attention has to be paid to the storage of the co-substrates as well as to the optimal utilisation of the energy produced in excess.     

Was? Wie? Warum? Jugendliche erforschen Flusslandschaften – Förderung des Systemverständnisses als Basis für gelebte Partizipation im Flussgebietsmanagement

River landscape planning and management to promote the positive long-term development of river landscapes must adhere to the principle of sustainability. In this context, the goal is to initiate a development process for river landscapes that successfully reconciles the requirements of nature and water conservation with social and economic aspects, and which actively involves affected citizens in the decision-making process. A systems-based understanding and the opportunity to make ecologically relevant decisions are essential prerequisites for participative processes.     

Gemeinsame österreichisch-ungarische Sedimentforschung im Rahmen des EFRE-Projektes SEDDON

The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m³/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed.     

Integrierte gewässerökologische Modellansätze zur Beurteilung von Gewässervernetzungsvarianten am Beispiel der Unteren Lobau

Floodplains and wetlands are among the most endangered ecosystems worldwide. River-regulation and flood protection measures cut off these formerly highly dynamic systems from their natural water level fluctuations and water exchange conditions leading to siltation processes. Restoration measures to counteract these developments need to be assessed for the effect on currently established habitats and communities in order to estimate their effects, as species with different habitat preferences and different protection status do react distinctly different. This article will present how habitat modelling was used in a case study of the Untere Lobau to assess and predict the effects of potential management measures. The Untere Lobau is a wetland ecosystem of the Danube east of Vienna. It is part of the national park Donau-Auen and a protected area according to the EU habitat-directive. Prior to the river regulation, at the end of the 19^th century, the Untere Lobau was a dynamic floodplain. Today, siltation processes endanger especially the status of the aquatic habitats. Three management options were investigated: 1) business as usual – No implementation of additional hydrological measures, thus siltation processes are not mitigated; 2) a water enhancement scheme – A small amount of water is supplied to preserve the water bodies at the current status quo; 3) partly reconnection – An upstream reconnection of the floodplain to the main channel of the Danube, leading to a more rheophilic characteristic of the system moving towards conditions prior regulation. Based on a model approach and calculating habitat preferences via binary logistic regressions of selected species from different organism groups, an increase or decrease of available suitable habitat area (weighted usable areas) could be estimated. This study proofed clearly that models can assess the effects of hydrological management measures on the biocenosis and that they are a valuable tool for supporting the decision taking process in wetland management.     

宜昌的N种打开方式

正宜昌悠久的历史给我们留下了丰富灿烂的特色文化遗存。目前,宜昌已有入选联合国教科文组织人类非物质文化遗产代表作名录1项、国家级非物质文化遗产名目20项、省级52项、市级154项、县(市、区)级494项;非物质文化遗产项目代表性传承人国家级17人、省级110人、市级543人、县(市、区)级2050人;非物质文化遗产传承示范基地省级2个、市级28个。如果将宜昌视作为电脑桌面上的一个文件,那么这些非物质文化遗产就是打开宜昌的方式之一。