CONFLICT AND COOPERATION OVER INTERNATIONAL FRESHWATER RESOURCES: INDICATORS OF BASINS AT RISR1

ABSTRACT: In this paper we seek to identify historical indicators of international freshwater conflict and cooperation and to create a framework to identify and evaluate international river basins at potential risk for future conflict. We derived biophysical, socioeco‐nomic, and geopolitical variables at multiple spatial and temporal scales from GIS datasets of international basins and associated countries, and we tested these variables against a database of historical incidents of international water related cooperation and conflict from 1948 to 1999. International relations over freshwater resources were overwhelmingly cooperative and covered a wide range of issues, including water quantity, water quality, joint management, and hydropower. Conflictive relations tended to center on quantity and infrastructure. No single indicator—including climate, water stress, government type, and dependence on water for agriculture or energy—explained conflict/cooperation over water. Even indicators showing a significant correlation with water conflict, such as high population density, low per capita GDP, and overall unfriendly international relations, explained only a small percentage of data variability. The most promising sets of indicators for water conflict were those associated with rapid or extreme physical or institutional change within a basin (e.g., large dams or internationalization of a basin) and the key role of institutional mechanisms, such as freshwater treaties, in mitigating such conflict.     

Methane and nitrous oxide emissions from a subtropical coastal embayment (Moreton Bay,Australia)

Surface water methane (CH₄) and nitrous oxide (N₂O) concentrations and fluxes were investigated in two subtropical coastal embayments (Bramble Bay and Deception Bay, which are part of the greater Moreton Bay, Australia). Measurements were done at 23 stations in seven campaigns covering different seasons during 2010–2012. Water–air fluxes were estimated using the Thin Boundary Layer approach with a combination of wind and currents-based models for the estimation of the gas transfer velocities. The two bays were strong sources of both CH₄ and N₂O with no significant differences in the degree of saturation of both gases between them during all measurement campaigns. Both CH₄ and N₂O concentrations had strong temporal but minimal spatial variability in both bays. During the seven seasons, CH₄ varied between 500% and 4000% saturation while N₂O varied between 128 and 255% in the two bays. Average seasonal CH₄ fluxes for the two bays varied between 0.5 ± 0.2 and 6.0 ± 1.5 mg CH₄/(m²·day) while N₂O varied between 0.4 ± 0.1 and 1.6 ± 0.6 mg N₂O/(m²·day). Weighted emissions (t CO₂-e) were 63%–90% N₂O dominated implying that a reduction in N₂O inputs and/or nitrogen availability in the bays may significantly reduce the bays' greenhouse gas (GHG) budget. Emissions data for tropical and subtropical systems is still scarce. This work found subtropical bays to be significant aquatic sources of both CH₄ and N₂O and puts the estimated fluxes into the global context with measurements done from other climatic regions.     

Two‐Stage Ditch Floodplains Enhance N‐Removal Capacity and Reduce Turbidity and Dissolved P in Agricultural Streams

Two‐stage ditches represent an emerging management strategy in artificially drained agricultural landscapes that mimics natural floodplains and has the potential to improve water quality. We assessed the potential for the two‐stage ditch to reduce sediment and nutrient export by measuring water column turbidity, nitrate (NO₃^?), ammonium (NH₄⁺), and soluble reactive phosphorus (SRP) concentrations, and denitrification rates. During 2009‐2010, we compared reaches with two‐stage floodplains to upstream reaches with conventional trapezoid design in six agricultural streams. At base flow, these short two‐stage reaches (<600 m) reduced SRP concentrations by 3‐53%, but did not significantly reduce NO₃^? concentrations due to very high NO₃^? loads. The two‐stage also decreased turbidity by 15‐82%, suggesting reduced suspended sediment export during floodplain inundation. Reach‐scale N‐removal increased 3‐24 fold during inundation due to increased bioreactive surface area with high floodplain denitrification rates. Inundation frequency varied with bench height, with lower benches being flooded more frequently, resulting in higher annual N‐removal. We also found both soil organic matter and denitrification rates were higher on older floodplains. Finally, influence of the two‐stage varied among streams and years due to variation in stream discharge, nutrient loads, and denitrification rates, which should be considered during implementation to optimize potential water quality benefits.     

Getting to the First Handshake: Enhancing Security by Initiating Cooperation in Transboundary River Basins

How does transboundary water cooperation begin at the initial stages, and how can third parties help to foster said cooperation? Many nations with transboundary waters do not cooperate or have ceased cooperation. Yet cooperation often prevails, resulting in 688 water‐related treaties signed from 1820 to 2007. We address the following: by which practices can development partners best design and implement cooperative projects at the state level to enhance basin water security in the earliest stages? This article identifies strategies for initiating cooperation and lessons drawn from reviewing select cases. We compiled from the Oregon State University Transboundary Freshwater Dispute Database all transboundary water resources projects over the last decade with multinational participation. We selected 10 case studies that enhance water security that fit the following filtering criteria: (1) Funding exclusively/primarily from outside sources, (2) Including nonofficial stakeholders in project design/implementation, (3) Absence of formal relations around water resources between or among the riparian nations before the project was discussed, (4) Project design possibly enhancing hydropolitical relations. Findings suggest that to enhance water security, project designs should respect participating riparians' autonomies, create basin‐wide networks of scientists, allow for each partner to garner responsibility for project activities, and consult a diverse group of stakeholders.     

Plastic pollution: A focus on freshwater biodiversity

Plastics are dominant pollutants in freshwater ecosystems worldwide. Scientific studies that investigated the interaction between plastics and freshwater biodiversity are incipient, especially if compared to the marine realm. In this review, we provide a brief overview of plastic pollution in freshwater ecosystems around the world. We found evidence of plastic ingestion by 206 freshwater species, from invertebrates to mammals, in natural or semi-natural ecosystems. In addition, we reported other consequences of synthetic polymers in freshwater ecosystems—including, for instance, the entanglement of animals of different groups (e.g., birds). The problem of plastic pollution is complex and will need coordinated actions, such as recycling programs, correct disposal, stringent legislation, regular inspection, replacement of synthetic polymers with other materials, and ecological restoration. Current information indicates that the situation in freshwater ecosystems may be as detrimental as the pollution found in the ocean, although highly underappreciated.Supplementary InformationThe online version of this article (10.1007/s13280-020-01496-5) contains supplementary material, which is available to authorized users.     

Occurrences and potential risks of 16 fragrances in five German sewage treatment plants and their receiving waters

Fragrances are used in a wide array of everyday products and enter the aquatic environment via wastewater. While several musk compounds have been studied in detail, little is known about the occurrence and fate of other fragrances. We selected 16 fragrance compounds and scrutinized their presence in Bavarian sewage treatment plants (STP) influents and effluents and discussed their ecological risks for the receiving surface waters. Moreover, we followed their concentrations along the path in one STP by corresponding time-related water sampling and derived the respective elimination rates in the purification process. Six fragrance substances (OTNE, HHCB, lilial, acetyl cedrene, menthol, and, in some grab samples, also methyl-dihydrojasmonate) could be detected in the effluents of the investigated sewage treatment plants. The other fragrances under scrutiny were only found in the inflow and were eliminated in the purification process. Only OTNE and HHCB were found in the receiving surface waters of the STP in congruent concentrations, which exceeded the preliminary derived environmental thresholds by a factor of 1.15 and 1.12, respectively, indicating potential risks. OTNE was also detected in similar concentration ranges as HHCB in muscles and livers of fish from surface waters and from ponds that are supplied with purified wastewater. The findings show that some fragrance compounds undergo high elimination rates, whereas others—not only musks—are present in receiving surface water and biota and may present a risk to local aquatic biota. Hence, our results suggest that the fate and potential effects of fragrance compounds in the aquatic environment deserve more attention.     

Kosovo-Konflikt: Ökologische Auswirkungen

10 years ago, the WWF (World Wide Fund for Nature) began to support the work of environmental protection in the countries of Eastern Europe. A main topic is the Danube-Carpathian Program. With the beginning of the bombardements, connected with great amounts of chemicals released directly and as clouds from the fires and explosions, the question raises: What are the consequences for mankind and nature? Is there a risk for the Danube-Carpathian Program? The WWF feels responsible for reporting about these consequences. In July 1999, a group of two Oil Experts and two scientists (each a chemist and a toxicologist) visited Belgrad, Pan?evo and Novi Sad, took samples of soil and water, and estimated the contents of dangerous substances. The first findings and the first consequences for nature and human health are described.     

Large-scale patterns of shell variation in Littorina striata, a planktonic developing periwinkle from Macaronesia (Mollusca: Prosobranchia)

Littorina striata King and Broderip, 1832 is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species displays a high degree of shell variation involving size and sculpture (nodulose vs smooth shells). The present work provides a preliminary account of some aspects of this shell variation on wave-exposed shores over the entire geographical range of the species. Based on morphological patterns observed among other prosobranchs it was predicted that southern specimens of L. littorina should on the average be larger, heavier, more nodulose, and should show more shell repair marks, than northern specimens. These expectations were confirmed for shell size and weight. In contrast, there was no consistent pattern in nodulosity between archipelagos, even though there were differences at much smaller scales. Shell repair marks were more prevalent in northern populations, but this trend was only due to a significant N–S difference among nodulose shells. This is surprising as nodulose shells displayed significantly fewer shell repair marks than smooth shells. These observations were tentatively interpreted as a function of presumed differential N–S patterns of wave action and ambient temperatures. In this context, wave action in Macaronesia seems to increase in the south (contrary to what current theories predict). This atypical situation may confound the interpretation of morphological patterns in L. striata so that firm conclusions cannot be drawn without further experimental work at different spatial scales. Nevertheless, it seems that generalisations about macrogeographic shell morphology patterns, based on interspecific comparisons, are not directly applicable to intraspecific patterns, and may strongly depend on local conditions which make adequate sampling and data treatment very difficult. Received: 10 September 1997 / Accepted: 15 January 1998     

Fragrances in the Environment: Pleasant odours for nature? (9 pp)

Goal, Scope and Background Fragrance preparations or perfumes are used in an increasing variety of applications, as for example washing, cleansing, personal care products, consumer goods or in applications to modify indoor air. However, up to now, little is known to the general or scientific public about their chemical identity and the use pattern of single substances, not even for high production volume chemicals. Some toxicological data are published for a comparatively small number of substances with a focus on sensitisation and dermal effects, while other effects are neglected. Information on ecotoxicity and environmental fate are rare, especially for long-term exposure. Data for a detailed hazard and risk analysis are available in exceptional cases only. According to the current legal situation, fragrance industry is self-regulated, which means that pre-market risk evaluation is not required for most fragrances. Odour and the ability to smell play a major role for wildlife for all taxonomic groups. Reproductive and social behaviour, defence, communication and orientation depend on volatile compounds which can be identical to those used in fragrance preparations. Our interdisciplinary approach leads to the question of whether and, if so, to what extent anthropogenic fragrances may influence life and reproduction of organisms in the environment. Main Features Information from literature on use, exposure and biological effects was combined to analyse the state of knowledge. Following an overview of the amounts of fragrances used in different consumer products and their release into the environment, the roles of odours in nature are shown for a selection of compounds. Existing regulation was analysed to describe the data basis for environmental risk evaluation. Finally, recommendations for further action are derived from these findings. Results Three main results were elaborated: First, fragrance substances are continuously discharged in large amounts into the environment, especially via the waste water. Second, there are some indications of negative effects on human health or the environment, although the data basis is very thin due to the self regulation of the fragrance industry and the regulatory situation of fragrance substances. Third, many odoriferous substances used by man are identical to those which are signal substances of environmental organisms at very low concentrations, thus giving rise to specific mode of actions in the ecosystem. Recommendations For the adequate risk assessments of fragrances, test results on their unspecific as well as their specific effects as signal substances are needed. This would imply prioritisation methods and development of useful test methods for specific endpoints for appropriate risk assessments. Before a comprehensive testing and evaluation of results has been finished, a minimization of exposure should be envisaged. Eco-labelling of products containing acceptable fragrance ingredients could be a first step and provide consumers with the respective information. Transparency concerning the fragrance ingredients used and their biological potency will help to build up confidence between producers and consumers. Conclusions and Perspectives The interdisciplinary approach, bringing together chemical, biological, toxicological and ecotoxicological data with information provided by manufacturers and with legal and consumer aspects, offers new insights into the field of fragrance substances used in consumer products. The amounts and application fields of fragrance substances increases while fate and effects in the environment are hardly known. The current legal situation is not suited to elucidate the effects of fragrances on human health and the environment sufficiently, especially as it was shown that fragrances may play a considerable role in the ecosystem on the behaviour of organisms. According to the precautionary principle, the lack of knowledge should best be tackled by reducing exposure, especially for compounds such as fragrance substances where no ethical reasons object a substitution by less hazardous chemicals. ESS-Submission Editor: Dr. Thomas Knacker (th-knacker@ect.de)