Catchment management in the developing world rarely include detailed hydrological components. Here, changes in the hydrological response of a 200-ha catchment management in north Ethiopia are investigated. The management included various soil and water conservation measures such as the construction of dry masonry stone bunds and check dams, the abandonment of post-harvest grazing and the establishment of woody vegetation. Measurements at the catchment outlet indicated a runoff depth of 5 mm or a runoff coefficient (RC) of 1.6 % in the rainy season of 2006. Combined with runoff measurements at plot scale, this allowed calculating the runoff Curve Number (CN) for various land uses and land management techniques. The pre-implementation runoff depth was then predicted using the CN values and a ponding adjustment factor, representing the abstraction of runoff induced by the 242 check dams in gullies. Using the 2006 rainfall depths, the runoff depth for the 2000 land management situation was predicted to be 26.5 mm (RC = 8 %), in line with current RCs of nearby catchments. Monitoring of the ground water level indicated a rise after catchment management. The yearly rise in water table after the onset of the rains (∆T) relative to the water surplus (WS) over the same period increased between 2002-2003 (∆T/WS = 3.4) and 2006 (∆T/WS >11.1). Emerging wells and irrigation are other indicators for improved water supply in the managed catchment. Cropped fields in the gullies indicate that farmers are less frightened for the destructive effects of flash floods. Due to an increased soil water content, the crop growing period is prolonged. It can be concluded that this catchment management has resulted in a higher infiltration rate and a reduction of direct runoff volume by 81 % which has had a positive influence on the catchment water balance.

HighlightsComposite indicators are widely used in sustainable development and elsewhere.The effect of weights used in aggregating indicators is complex.Three tools are presented which help developers and users to investigate effects of weights.Case studies related to sustainable development demonstrate the benefits.

Green infrastructure (GI), a network of nature, semi-natural areas and green space, delivers essential ecosystem services which underpin human well-being and quality of life. Maintaining ecosystem services through the development of GI is therefore increasingly recognized by policies as a strategy to cope with potentially changing conditions in the future. This paper assessed how current trends of land-use change have an impact on the aggregated provision of eight ecosystem services at the regional scale of the European Union, measured by the Total Ecosystem Services Index (TESI8). Moreover, the paper reports how further implementation of GI across Europe can help maintain ecosystem services at baseline levels. Current demographic, economic and agricultural trends, which affect land use, were derived from the so called Reference Scenario. This scenario is established by the European Commission to assess the impact of energy and climate policy up to 2050. Under the Reference Scenario, economic growth, coupled with the total population, stimulates increasing urban and industrial expansion. TESI8 is expected to decrease across Europe between 0 and 5 % by 2020 and between 10 and 15 % by 2050 relative to the base year 2010. Based on regression analysis, we estimated that every additional percent increase of the proportion of artificial land needs to be compensated with an increase of 2.2 % of land that qualifies as green infrastructure in order to maintain ecosystem services at 2010 levels.

An overall approach to assess the effectiveness of soil conservation measures at catchment scale is the comparison of sediment budgets before and after implementation of a catchment management programme. In the May Zeg-zeg catchment (187 ha) in Tigray, north Ethiopia, integrated catchment management has been implemented since 2004: stone bunds were built in the whole catchment, vegetation was allowed to re-grow on steep slopes and other marginal land, stubble grazing abandoned, and check dams built in gullies. Land use and management were mapped and analysed for 2000 and 2006, whereby particular attention was given to the quantification of changes in soil loss due to the abandonment of stubble grazing. Sediment yield was also measured at the catchment's outlet. A combination of decreased soil loss (from 14·3 t ha -1 y -1 in 2000 to 9·0 t ha -1 y -1 in 2006) and increased sediment deposition (from 5·8 to 7·1 t ha -1 y -1 ) has led to strongly decreased sediment yield (from 8·5 to 1·9 t ha -1 y -1 ) and sediment delivery ratio (from 0·6 to 0·21). This diachronic comparison of sediment budgets revealed that integrated catchment management is most effective and efficient and is the advisable and desirable way to combat land degradation in Tigray and other tropical mountains. policy information, qualitative (process interaction) and quantitative (process rates), about erosion and sediment deposition.Geomorphologists use sediment budgets to investigate the relative importance of the different components and their Figure 9. Sediment budgets for MZZ catchment in 2000 (left) and 2006 (right) with computation of sediment sources and sinks. Width of arrows is proportional to sediment masses involved.

a b s t r a c tWater, food and energy are at the core of human needs and there is a boundless complex cycle among these three basic human needs. Ecosystems are in the center of this nexus, since they contribute to the provision of each component, making it imperative to understand the role of ecosystems in securing food, water and energy for human well-being. In this study we aimed to map and assess water provisioning services and associated benefits to support the ecosystem-water-food-energy nexus by taking into account environmental flow requirements for riverine ecosystems using the hydrological model Soil and Water Assessment Tool (SWAT). We developed a framework that includes indicators of renewable water (capacity of ecosystem to provide water) and water use (service flow) and we applied it in the Danube river basin over the period 1995-2004. Water scarcity indicators were used to map the possible water scarcity in the subbasins, and analyze the spatial match of water availability and water use. The results show that modelling is instrumental to perform the integrated analysis of the ecosystem-waterfood-energy nexus; and that spatial mapping is a powerful tool to display environmental availability of water provisioning and regulatory services delivered by ecosystems, and can support the nexus analysis.

New psychoactive substances (NPS) are synthesized compounds that are not usually covered by European and/or international laws. With a slight alteration in the chemical structure of existing illegal substances registered in the European Union (EU), these NPS circumvent existing controls and are thus referred to as "legal highs". They are becoming increasingly available and can easily be purchased through both the internet and other means (smart shops). Thus, it is essential that the identification of NPS keeps up with this rapidly evolving market. In this case study, the Belgian Customs authorities apprehended a parcel, originating from China, containing two samples, declared as being "white pigments". For routine identification, the Belgian Customs Laboratory first analysed both samples by gas-chromatography mass-spectrometry and Fourier-Transform Infrared spectroscopy. The information obtained by these techniques is essential and can give an indication of the chemical structure of an unknown substance but not the complete identification of its structure. To bridge this gap, scientific and technical support is ensured by the Joint Research Centre (JRC) to the European Commission Directorate General for Taxation and Customs Unions (DG TAXUD) and the Customs Laboratory European Network (CLEN) through an Administrative Arrangement for fast recognition of NPS and identification of unknown chemicals. The samples were sent to the JRC for a complete characterization using advanced techniques and chemoinformatic tools. The aim of this study was also to encourage the development of a science-based policy driven approach on NPS. These samples were fully characterized and identified as 5F-AMB and PX-3 using (1)H and (13)C nuclear magnetic resonance (NMR), high-resolution tandem mass-spectrometry (HR-MS/MS) and Raman spectroscopy. A chemoinformatic platform was used to manage, unify analytical data from multiple techniques and instruments, and combine it with chemical and structural information.

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The hydrodynamic behaviour of a sloped phreatic aquifer in the Tigray Highlands in northern Ethiopia is described. The aquifer is situated in the soils of a plateau on top of a basalt sequence and lies on steep slopes; the latter lead to hydraulic gradients that can cause high discharge fluxes. Distinct wet and dry seasons characterize the climate of the Tigray Highlands and recharge is absent during the dry season. Because of the fertile vertisols that have developed, the plateau is heavily cultivated and thus has great local economic, and hence social, importance. Water for land irrigation is almost exclusively delivered by rainfall, which is largely restricted to the period June-September. During the dry season, the water table drops dramatically and the aquifer drains nearly completely, under the strong gravity-driven, sustained discharges. This study strives to give insights into recharge and discharge mechanisms of the aquifer, in order to improve the effectiveness of the implemented water conservation measures.Key words groundwater recharge; integrated water balance; water management; runoff; soil moisture balance; MODFLOW; Ethiopia Recharge et écoulement hydrogéologiques dans un petit bassin versant de montagne en Ethiopie du nordRésumé L'article décrit le comportement hydrodynamique d'un aquifère phréatique incliné dans les Tigray Highlands en Ethiopie du nord. L'aquifère se situe dans les sols d'un plateau aux pentes raides, au sommet d'une séquence basaltique. L'escarpement cause des gradients hydrauliques conduisant à des écoulements importants. Les saisons humide et sèche bien différenciées caractérisent le climat des Tigray Highlands, et la recharge est nulle pendant la saison sèche. A cause des vertisols fertiles, le plateau est intensément cultivé et présente par conséquent une valeur locale économique et sociale importante. L'eau d'irrigation provient presque exclusivement de la pluie, qui est largement limitée à la période Juin-Septembre. Pendant la saison sèche, la nappe descend énormément, et l'aquifère est presque complètement drainé, en raison des flux gravitaires continus importants. Cette étude continue à la compréhension des mécanismes de recharge et d'écoulement de l'aquifère, dans le but d'améliorer l'efficacité des mesures implémentées de conservation de l'eau.