Impact of reduced anthropogenic emissions and century flood on the phosphorus stock, concentrations and stocks in the Upper Danube

AbstractPatterns of changes in the concentration of total and soluble reactive phosphorus (TP, SRP) and suspended sediments at different flow levels from 1991 to 2013 in the Austrian Danube are statistically analyzed and related to point and diffuse emissions, as well as to extreme hydrological events. Annual loads are calculated with three methods and their development in time is examined taking into consideration total emissions and hydrological conditions. The reduction of point discharges achieved during the 1990s was well translated into decreasing TP and SRP baseflow concentrations during the same period, but it did not induce any change in the concentrations at higher flow levels nor in the annual transport of TP loads. A sharp and long-lasting decline in TP concentration, affecting all flow levels, took place after a major flood in 2002. It was still visible during another major flood in 2013, which recorded lower TP concentrations than its predecessor. Such decline could not be linked to changes in point or diffuse emissions. This suggests that, as a result of the flood, the river system experienced a significant depletion of its in-stream phosphorus stock and a reduced mobilization of TP rich sediments afterwards. This hypothesis is corroborated by the decoupling of peak phosphorus loads from peak maximum discharges after 2002. These results are highly relevant for the design of monitoring schemes and for the correct interpretation of water quality data in terms of assessing the performance of environmental management measures

Belastung des Neusiedler Sees mit anthropogenen Spurenstoffen: Überlegungen zu Herkunft und Verhalten

In this paper, we first present the contamination of Lake Neusiedl with anthropogenic trace substances regulated at national or EU level. Second, we identify main emission pathways for selected substances into the River Wulka and Lake Neusiedl and identify the potential environmental behaviour of trace substances in the aquatic system. Even if a comprehensive monitoring of all regulated substances in the lake is at present still missing, we can assume the compliance with environmental quality standards for most of them based on measurements carried out in the River Wulka and from biota-monitoring in the lake. For some substances quality criteria are not or probably not met, for others a final diagnosis is currently not possible due to analytical constraints. Depending on the examined substance, effluents from waste water treatment plants, agricultural erosion or atmospheric deposition on the lake surface may be the dominant pathway of contamination into the River Wulka and Lake Neusiedl. Besides specific considerations for individual substances, taking into account the enormous number of anthropogenic trace substances that are released into the environment, Lake Neusiedl must be regarded as especially vulnerable to this kind of contamination. The high vulnerability mainly derives from the lake acting as a substance-sink. Persistent chemicals which enter the lake may concentrate in the water of the lake or may be stored in the sediments of the reed belt, from where they might be mobilized later on. Even if many of the highly persistent chemicals are removed from the lake water through degradation or conversion to metabolites, little is known about the end products of this conversion and they cannot be monitored completely because of their high number. As a basis for the development of strategies for a long-term and efficient management of the lake, a regular monitoring of trace substances in lake and reed belt should be reinforced considerably to detect any undesirable developments as early as possible.EU-Projekt ATHU53 REBEN5225361

Stoffbilanzmodellierung für Spurenstoffe auf Einzugsgebietsebene

Stand: 28. Juli 202036

Occurrence and levels of micropollutants across environmental and engineered compartments in Austria

Occurrence and concentration of a broad spectrum of micropollutants are investigated in Austrian river catchments, namely polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), organotin compounds, perfluoroalkyl acids (PFAAs) and metals. The parallel analysis across multiple environmental and engineered compartments sheds light on the ratio of dissolved and particulate transport and on differences in concentration levels between point and diffuse emission pathways. It is found that some PAHs and organotins are present in rivers, groundwater and bulk deposition at higher concentrations than in municipal wastewater effluents. Among PFAAs and metals, highest concentrations were recorded either in atmospheric deposition or in discharges from wastewater treatment plants. The relevance of the analysis across compartments is best shown by the case of perfluorooctanesulfonic acid (PFOS). Despite municipal wastewater effluents being the emission pathway with highest concentrations, this study reveals that not only rivers, but also atmospheric deposition and groundwater sometimes exceed the environmental quality standard for surface waters. Moreover, this work reveals partially counterintuitive patterns. In rivers with treated wastewater discharges, increasing levels of dissolved compounds were measured at rising flow conditions, whereas the opposite would be expected owing to the dilution effect. This might derive from the mobilisation from soil or suspended particulate matter or rather find its explanation in high concentrations in atmospheric deposition. These hypotheses require however being tested through targeted studies. Additional future research includes the analysis of how regional or catchment specific characteristics might alter the relative importance of different emission pathways, and the modelling of emission and river loads to assess their relative contribution to river pollution.Federal Ministry of Sustainability and Tourism (BMNT)6366531

Novel approaches to enhance regional nutrients management and monitoring applied to the Austrian phosphorus case study

Zusammenfassung in deutscher SpracheWie viele andere Länder Europas und der Welt ist Österreich in hohem Maß auf Importe angewiesen, um den hohen Phosphor bedarf des Lebensmittelproduktionssystems zu stillen. Als Rohstoff wird Phosphor (P) aus begrenzten und nicht-erneuerbaren Phosphaterzen gewonnen, deren Produktion auf wenige Länder beschränkt ist. Aufgrund der großen wirtschaftlichen Bedeutung bzw. des zukünftigen Versorgungsrisikos hat die Europäische Kommission im Jahre 2014 Phosphaterz als kritischen Rohstoff definiert. Der P-Gebrauch weist in Österreich und in Europa mehrere Ineffizienzen und Verluste auf. Zudem ist P nicht nur eine essentielle Ressource, sondern auch ein Schadstoff in Wasserkörpern, wo hohe P-Konzentrationen zu Eutrophierung führen können. Forschungsaktivitäten sind erforderlich, um P-Flüße und -Lager durch natürliche und anthropogene Prozesse zu verstehen. Deren Ziel ist es, Maßnahmen zu identifizieren, die zur effizienteren Ressourcennutzung bzw. zu niedrigeren Emissionen und Verlusten und zur geringeren Importabhängigkeit führen können. Die Materialflussanalyse (MFA) ist eine geeignete Methodik für derartige Untersuchungen. Sie wurde häufig angewendet um meist statische P-Haushalte auf verschiedenen geographischen Ebenen zu darzustellen. Zeitliche Veränderungen wurden jedoch häufig vernachlässigt, obwohl sie relevante Informationen im Hinblick auf die Entwicklung von Managementstrategien und auf die Leistungskontrolle liefern können. In dieser Dissertation wird ein mehrjähriges MFA-Modell entwickelt und untersucht, das dem österreichischen P-Haushalt von 1990 bis 2011 entspricht. Die systematische Analyse dieses Modells zeigt, dass sogar in diesem vergleichsweise kurzen und stabilen Zeitraum P-Flüße und -Lager erheblich geändert wurden.Relevante Trends in Bezug auf Managementleistungen bzw. die Auswirkung von scheinbar nicht zusammenh ängenden gesetzlichen und wirtschaftlichen Entwicklungen auf P-Flüße wurden identifiziert. Außerdem hat die detaillierte Untersuchung der zeitlichen Muster zu Ergebnissen geführt, die sehr relevant im Bereich Wassergüte sind - speziell angesichts der Emissionen in die Gewässer. Es wurde festgestellt, dass sich die Verminderung von PEmissionen über Punktquellen in den 1990ern in geringeren Konzentrationen bei niedrigen Durchflussraten in der Donau umgehend widerspiegelte, aber nicht in geringeren Frachten. Die in dieser Dissertation aufgestellte und durch die Analyse gestützte Hypothese lautet: nur nachdem das große Hochwasser im Jahre 2002 die Gewässersohle intensiv aufgerissen hatte und nachdem es das durch mehrjährige Retention akkumulierte P-Lager abgebaut hatte, spiegelte sich die geringere Verfügbarkeit vom gelösten Paus Punktquellen in verminderten Frachten wider. Es ist daher erforderlich, die verflöchtenen Auswirkungen von anthropogenen Maßnahmen und hydrologischen Prozessen in großen Flüßen zu betrachten, um die Leistung des Umweltmanagements angemessen zu interpretieren. Das MFA-Modell des österreichischen P-Haushalts soll nicht nur angewendet werden, um die Entscheidunsträger über den Status quo und die bestehenden Probleme zu informieren, sondern es soll auch als Grundlagefürdie Begutachtung verschiedener Lösungsansätze dienen.Verschiedene Massnahmen sind vorhanden, um das System zu optimieren. Das detaillierte System des MFA-Modells ermöglicht den Vergleich von den relativen Beiträgen der verschiedenen Massnahmen, was behilflich bei der Festlegung von Prioritäten ist. Die Ergebnisse zeigen, dass Recycling von Abfallströmen und Verbrauchsminderung ein ähnliches Potential zur Senkung der Importabhängigkeit aufweisen, obwohl letzteres von höherer Unsichereit und von komplexeren Herausforderungen betroffen ist. Wenn sämtliche Maßnahmen umgesetzt würden und maximale Anstrengung unternommen würde, könnte Österreich P-Mineraldünger vollständig ersetzen bzw. die Emissionen um 28% und die Importabhängigkeit um 89% reduzieren. Solche Ziele sollten als erreichbare Maximumwerte und nicht unbedingt als Optima angesehen werden, da diese Bewertung weder Kosten noch weitere Umweltaspekte berücksichtigt, die in weiteren Forschungsarbeiten erfasst werden müssen. Ferner wurde die Datenqualität durch ein Indikatorenset charakterisiert. Es wurde dargestellt, wie verschiedene Aspekte der Datenqualität sich im Laufe der Zeit geändert haben, und wie die Berücksichtigung der Unsichereit unsere Fähigkeit stark beeinflusst Flüße und Lager zu überwachen. Das hat auch dazu beigetragen, die Verbesserung der Datenerhebung zu priorisieren. Abschließend stellt diese Dissertation die Machbarkeit und die mehrfachen Vorteile dar, die ein regionales auf mehrjärige MFA gestütztes Nährstoffmanagement anbiet. Die Integrierung derartiger Materialbuchführung in die reguläre Statistiken würde deshalb öffentliche Behörden unterstützen Governance-Strategien zu entwickeln, Zielsysteme zu definieren, Feedbacks und Gegenleistungen zwischen Maßnahmen zu verstehen, Managementleistungen zu beobachten bzw. Datenerhebung zu priorisieren.Austria, like the rest of Europe and most of other world countries, relies heavily on imports to satisfy the high demand of phosphorus (P) of its food production system. P is obtained from phosphate rock, which is a finite and non-renewable resource confined in a handful of countries. Owing to the great economic importance of P and to future supply risk, in the year 2014 the European Commission included phosphate rock in its List of Critical Raw Materials. The domestic use of P in Austria and in the rest of Europe presents several inefficiencies and losses. Further, P is not only a fundamental resource but also a harmful pollutant in water bodies, where its excessive concentration can cause sever eutrophication problems. Research is needed to understand P flows and stocks through anthropogenic and natural compartments in order to identify where actions can be taken to increase use efficiency, to reduce losses and emissions and thus to lower import dependency. Material Flow Analysis (MFA) constitutes a suitable approach for such investigations and has been widely applied to describe mostly static P budgets at diverse geographical scales. Temporal dynamics have been however mostly neglected, although they can provide relevant information for the design of management strategies and for the monitoring of their performance. This Thesis presents a multiyear MFA model that represents the Austrian P budget from 1990 to 2011. The systematic analysis of this model reveals that even in this relatively short and stable period of time P flows and stocks have undergone significant changes. Relevant trends in management performance are identified as well as the impact of apparently unrelated regulatory or economic developments on P flows. Further, the investigation in detail of temporal patterns has led to findings highly relevant in the field of water quality and emissions to water bodies. It was found that the decline of P point discharges in the 1990s did immediately translate into lower concentrations at low flow conditions in the Danube, but not into lower loads. The hypothesis put forward in this Thesis and supported by the analyses is that only after the large flood in the year 2002 intensively scoured the river bed and depleted the in-stream P stock accumulated during years of net retention, the reduced availability of dissolved P primarily stemming from point discharges was reflected in lower loads. It is therefore necessary to consider more thoroughly the interweaving effects of anthropogenic measures and hydrological processes in large rivers, in order to properly interpret and assess the performance of environmental management. The MFA model of the Austrian P budget should not only be applied to inform policy makers on the status quo and on the existing problems, but also as a basis to provide a solid assessment of possible solutions and improvements. A wide range of different actions is available to optimize the system. The detailed system provided by the MFA model allows the comparison of the relative contribution of the measures, which helps in setting priorities. The results show that both recycling from waste streams and reduction of consumption hold similar potentials to decrease import dependency, although the latter are affected by higher uncertainty and more complex challenges. If the whole set of actions were implemented and a maximum effort of P governance were undertaken, Austria could fully replace the use of mineral fertilizers, reduce emissions to water bodies by 28% and its import dependency by 89%. These shall be considered maximum achievable targets, but are not necessarily optimal, since this assessment still does not include costs and other environmental aspects, which need to be included in future research. Moreover, this work has characterized data quality through a set of indicators, has assessed how different aspects of data quality have improved or changed over time, has shown to which extent the consideration of uncertainty influences the ability of monitoring flows and stocks and has contributed to prioritize the improvement of data collection schemes. In conclusion, this Thesis presents the feasibility and the manifold benefits provided by approaching regional nutrients management based on multiyear MFA. If public authorities integrated such an accounting scheme into their routine statistics and reporting, it could assist them in the design of governance strategies and target systems, in the understanding of feedbacks and trade-offs between measures, in the monitoring of their effectiveness, in getting feedbacks on data quality and on prioritizing data collection.13

Most relevant sources and emission pathways of pollution for selected pharmaceuticals in a catchment area based on substance flow analysis

The release of micropollutants in surface water depends on different sources and on different pathways. Through substance flow analysis, this study estimates the annual load of two pharmaceuticals (carbamazepine and sulfamethoxazole) in a catchment area, due to different emission pathways: wastewater treatment plant effluent, combined sewer overflows, and runoff from sludge and manure amended soil. It emerged that wastewater treatment plant effluent is the main emission pathway for carbamazepine (98.5% referring to the total released annual load) and land runoff (98%) for sulfamethoxazole. The study also investigates the parameters (including manure disposed on the land, removal efficiency and combined sewer overflow flowrate) which mostly influence the results, and those which are affected by higher uncertainty. The most uncertain parameters are those determining the fate of pharmaceuticals once in soil and surface water. The study concludes with a comparison between the predicted concentrations in different points of the receiving water body of the two key compounds, modeled with substance flow analysis, and those directly measured in a dedicated sampling campaign. The main discrepancies were found for sulfamethoxazole. Future research focusing on monitoring campaigns under different weather conditions and in different environmental compartments (soil and water) will certainly provide new insights in this kind of study