Water quality of the King Abdullah Canal/Jordan–impact on eutrophication and water disinfection

The King Abdullah Canal (KAC) is an artificial water conveyor serving as raw water source for drinking water supply of Amman and for irrigation purposes in the Jordan Valley. The main water sources for KAC originate from the Yarmouk River, the Mukheiba Wells, and the Peace Conveyor. Water samples were collected from December 2002 to May 2004 to investigate changes in physicochemical parameters and parameters related to eutrophication along KAC. The catchment area of KAC is highly heterogeneous in terms of topography, climate, geologic conditions, and land use, resulting in great variations in the physicochemical composition of the canal water. The Yarmouk River and the Mukheiba Wells reflect the water quality of precipitation without much dissolution of halides, whereas the Peace Conveyor shows a groundwater characteristic. Main dischargers of N and P compounds are the Yarmouk River, and dams and wadis along KAC. The concentrations in the canal are mostly above eutrophication level for N and P. Along KAC there is an increase in chlorophyll a concentration and plankton counts. The formation potentials for trihalomethanes (THMs) and for integrated organically bound halogens are determined by chlorination to evaluate the consequences of water disinfection. Due to relatively high bromide concentration mainly brominated THMs are formed.     

Four priorities for new links between conservation science and accounting research

Article impact statement: New collaborations with accounting research can improve conservation impact of ecosystem-based information systems.     

Decadal variability of floods in the northern foreland of the Tatra Mountains

Floods in the northern foreland of the Tatra Mountains considerably contribute to the total flood damage in Poland. Therefore, the question whether the magnitude and frequency of floods have changed in this region is of high interest. This study aims at investigating the inter-decadal variability of magnitude, frequency and seasonality of floods since the mid-twentieth century, to better understand regional changes. The analysis was accomplished in a multi-temporal approach whereby trends are fitted to every possible combination of start and end years in a record. Detected trends were explained by estimating correlations between the investigated flood parameters and different large-scale climate indices for the northern hemisphere, and by trends found in intense precipitation indices, number of days with snow cover, cyclonic circulation types, temperature and moisture conditions. Catchment and channel changes that occurred in the region over the past decades were also considered. Results show that rivers in the area exhibit considerable inter-decadal variability of flows. The magnitude and direction of short-term trends are heavily influenced by this inter-decadal variability; however, certain patterns are apparent. More extreme, although perhaps less frequent floods are now likely to occur, with a shift in the seasonality, decreasing flood magnitudes in winter and increasing during autumn and spring. The identification of the factors contributing to the occurrence of flood events and their potential changes is valuable to enhance the flood management in the region and to improve the resilience of the population in this mountainous area.     

Temporal and local trends of PCDD/F levels in cow's milk in Switzerland

Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) were determined in 30 Swiss cow's milk samples collected at dairy farms in the vicinity to point sources, in rural/alpine areas distant to known sources, and from tanks in large industrial milk processing plants. The contaminant concentrations in samples collected in 2001 were compared to data from analyses conducted in 1984 and 1990/1991 at the same sites. In 2001, the PCDD/F levels in milk from farms near point sources (0.63+/-0.26 ng I-TEQ/kg milk fat) are slightly but significantly higher in than milk from remote areas (0.36+/-0.09 ng I-TEQ/kg milk fat). Consumer milk collected at the processing plants had intermediary levels (0.51+/-0.19 ng I-TEQ/kg milk fat). However, milk in 2001 was significantly less contaminated than the samples collected in 1990/1991 and 1984. This trend is particularly pronounced near point sources but is also apparent in consumer milk and milk from remote areas. No geographical gradient in the atmospheric input of PCDD/F in Switzerland was found. The reduction in PCDD/F levels in dairy milk is paralleled by and correlated to the remediation of known PCDD/F emitting industries, as enforced by federal authorities.