Search

Mangrove wetlands provide essential ecosystem services such as coastal protection and fisheries. Metal pollution due to industrial and agricultural activities represents an issue of growing concern for the Guayas River Basin and related mangroves in Ecuador. Fisheries and the related human consumption of mangrove crabs are in need of scientific support. In order to protect human health and aid river management, we analyzed several elements in the Guayas Estuary. Zn, Cu, Ni, Cr, As, Pb, Cd, and Hg accumulation were assessed in different compartments of the commercial red mangrove crab Ucides occidentalis (hepatopancreas, carapax, and white meat) and the environment (sediment, leaves, and water), sampled at fifteen sites over five stations. Consistent spatial distribution of metals in the Guayas estuary was found. Nickel levels in the sediment warn for ecological caution. The presence of As in the crabs generated potential concerns on the consumers' health, and a maximum intake of eight crabs per month for adults is advised. The research outcomes are of global importance for at least nine Sustainable Development Goals (SDGs). The results presented can support raising awareness about the ongoing contamination of food and their related ecosystems and the corresponding consequences for environmental and human health worldwide. ispartof: FOODS vol:10 issue:8 ispartof: location:Switzerland status: published

Study area Kikuletwa catchment, Upper Pangani River Basin, Tanzania. Study focus This study compared yearly blue and green water fluxes using four different methods: Senay’s method (SN) (Senay et al., 2016), van Eekelen method (EK) (van Eekelen et al., 2015), the Budyko method (Simons et al., 2020) and the Soil Water Balance (SWB) model (FAO and IHE Delft, 2019). The yearly blue and green water fluxes of different Land Use Land Cover (LULC) classes were estimated using an ensemble of seven global remote sensing-based evapotranspiration products (Ensemble ET) and the CHIRPS rainfall dataset. The Ensemble ET was created from seven global RS-based surface energy balance models (GLEAM, CMRS-ET, SSEBop, ALEXI, SEBS, ETMonitor and MOD16). New hydrological insights Our study found that the EK method was able to map blue and green water fluxes with realistic results for irrigated and non-irrigation cultivated areas. Budyko and SWB gave too high blue water fluxes for the non-irrigated agricultural areas, whereas the Budyko and SWB models were not able to show a clear difference in blue-water fluxes in irrigated versus non-irrigated areas. On the other hand, the SN method estimated no blue water fluxes in more than half of the identified irrigated areas. Three of the four methods estimate the highest blue water fluxes (318–582 mm/y) in forested areas, while the SWB model estimates the highest blue water fluxes in irrigated banana and coffee (278 mm/y). Overall, we conclude that the EK method yielded the most realistic spatial pattern of blue-water fluxes when compared to the irrigated land use map, whereas SWB could be considered after further calibration if higher temporal data resolution (e.g. monthly) is required.

The Lake Tana Basin, comprising the largest natural lake in Ethiopia, is the source and the uppermost part of the Upper Blue Nile Basin. In this review paper, research papers, mainly on the rainfall-runoff modeling and lake water balance, and on the hydrogeology, have been reviewed. The earlier water balance estimation attempts used simple conceptual and statistical approaches and calculate on a monthly timescale. More recent research has been using advanced semi-physically or physically based distributed hydrological models. Accordingly, mean annual precipitation over the lake was estimated in the range 36.1–53.1%; lake evaporation at 45.3–57.5%; river inflow (all gauged and estimated ungauged) at 43.6–63.9%; and river (lake) water outflow at 0–9.2%. With the few isotope studies, groundwater inflow and outflow are found insignificant. Different studies had estimated groundwater recharge, ranging from 57 mm to 850 mm. The basin has a heterogenous aquifer system consisting of different volcanic rocks and alluvio-lacustrine sediments. Generally, groundwater with low TDS, Ca–Mg–HCO3 type, isotopically relatively enriched, and high TDS, Na–HCO3 type, isotopically relatively depleted, water types have been identified. In this paper, major research gaps such as aquifer hydraulic characterization, surface-groundwater interaction, groundwater flow and groundwater balance have been identified. Hence, future research shall focus on the groundwater resources, so that existing surface water studies are updated and future water usage options are explored.

Lakeshore wetlands are thought to be hot spots for biogeochemical processes. However, many lakeshore wetlands have been hydrologically disconnected from the associated lake by levees that have altered the ecosystem services they provide. Lakeshore restoration projects have been undertaken to recover the hydrological connection; however, the effects of the various restoration practices on biogeochemical cycling remain unclear. Here, we compared variation in sediment nitrogen (N) cycling rates to assess the restoration benefits of N removal in a series of recently hydrologically restored lakeshore wetlands, including ponds and bottomlands, of Lake Dianchi, China. The results showed that nitrification rates were generally higher in the ponds, while denitrification rates were higher in the bottomlands. Hydrological reconnection stimulated the development of several sediment properties critical for N cycling rates in the ponds, including increases in sediment carbon (C) and N contents; however, bottomland reconnection increased sediment moisture and decreased sediment C and N contents likely due to erosion by wind-induced wave action. Correspondingly, hydrological reconnection significantly increased the sediment N cycling rates in ponds but decreased the sediment N cycling rates in bottomlands over time. Path analyses revealed that substrate characteristics, including moisture and C and N availability, were the critical drivers regulating wetland N cycling rates. These results imply that the restoration targets could not be met simply by hydrological reconnection. Future wetland restoration requires further understanding of the relationship between changes in sediment properties and biogeochemical processes.

The upper Ganga Basin in Uttarakhand, India, has high hydropower potential and plays an important role in the development of the state economy. Thus, an accurate knowledge of annual water yield is of paramount importance to this region. This paper deals with use of contemporary water yield estimation models such as the distributed Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model and the Lumped Zhang model and their validation to identify the most suited one for water yield estimation in the upper Ganga Basin. In previous studies utilizing these models, water yield was estimated by considering a single value of some important model parameters for the entire basin, which in fact show distributed variation at a finer (pixel) scale. Therefore, in this study, pixel-level computations are performed to assess and ascertain the need for incorporating the spatial variation of such parameters in model applications. To validate the findings, the observed sub-basin discharge data are analyzed with the computed water yield for 4 decades, i.e., 1980, 1990, 2001 and 2015. The results obtained are in good agreement with the water yield obtained at the pixel scale.

Lake Tana is the most important freshwater lake in Ethiopia. Besides pressures on water quality resulting from urbanization and deforestation, the invasion of the exotic water hyacinth (Eichhornia crassipes) poses new threats to the ecosystem. Water hyacinth, endemic to South America, is widely considered as the world's worst aquatic invasive weed. In 2011, the weed appeared on the northern shores of Lake Tana, expanding in south-eastern direction. The lake area affected by water hyacinth was last estimated in 2015 at 34,500 ha, which equals 16% of the total lake surface. In this research, the benefits of water hyacinth control and eradication for the rural population inhabiting the northern and northeastern villages bordering Lake Tana, are investigated. In the area, the population largely depends on farming and fishing. An assessment of the total economic benefit of eradication was conducted. The stakeholder-centered approach led to measuring the willingness to contribute in labor and cash terms. Results showed smallholders in the study are willing to contribute over half-a-million euros annually. Costs of management actions can be weighed to the benefits, where further research is needed on the impact on other stakeholder groups. Moreover, wetland management should advance to explore multiple pathways in an integrated approach: water hyacinth control, water hyacinth utilization and sustainable waste water management. (C) 2020 International Association for Great Lakes Research. Published by Elsevier B.V. All rights reserved. The authors would like to thank the VLIR-UOS project for funding this research through Bahir Dar University-Institutional University Cooperation (BDU-IUC) program. Moreover, the authors acknowledge the financial support of the UNESCO MAB Programme and the Belgian Science Policy, within the frame of the EVAMAB project. This manuscript is one of the outputs of Work Packages B and D of the EVAMAB Project (Economic valuation of ecosystem services in Biosphere Reserves: testing effective rapid assessment methods in selected African Biosphere Reserves). The lead author, Van Oijstaeijen W., has received financial support for the research stay in the form of a VLIR-UOS Travel Grant and obtained a PhD fellowship strategic basic research by FWO under contract No 1S46420N. The authors would like to thank the associate editor and the reviewers for their thorough reviews and constructive feedback. Van Oijstaeijen, W (corresponding author), Univ Antwerp, Dept Engn Management, Antwerp, Belgium. wito.vanoijstaeijen@uantwerpen.be

The Amazon Basin is an unquestionable biodiversity hotspot, containing the highest freshwater biodiversity on earth and facing off a recent increase in anthropogenic threats. The current knowledge on the spatial distribution of the freshwater fish species is greatly deficient in this basin, preventing a comprehensive understanding of this hyper-diverse ecosystem as a whole. Filling this gap was the priority of a transnational collaborative project, i.e. the AmazonFish project - https://www.amazon-fish.com/. Relying on the outputs of this project, we provide the most complete fish species distribution records covering the whole Amazon drainage. The database, including 2,406 validated freshwater native fish species, 232,936 georeferenced records, results from an extensive survey of species distribution including 590 different sources (e.g. published articles, grey literature, online biodiversity databases and scientific collections from museums and universities worldwide) and field expeditions conducted during the project. This database, delivered at both georeferenced localities (21,500 localities) and sub-drainages grains (144 units), represents a highly valuable source of information for further studies on freshwater fish biodiversity, biogeography and conservation., Measurement(s)Diversity • Fish • spatial patternTechnology Type(s)digital curationFactor Type(s)geographic locationSample Characteristic - OrganismfishSample Characteristic - Environmentdrainage basinSample Characteristic - LocationAmazon Basin Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.11920800

The Zayandeh-Rud River basin, Iran, is projected to face spatiotemporally heterogeneous temperature increase and precipitation reduction that will decrease water supply by mid-century. With projected increase (0.70–1.03 °C) in spring temperature and reduction (6– 55%) in winter precipitation, the upper Zayandeh-Rud sub-basin, the main source of renewable water supply, will likely become warmer and drier. In the lower sub-basin, 1.1–1.5 °C increase in temperature and 11–31% decrease in annual precipitation are likely. A system dynamics model was used to analyze adaptation strategies taking into account feedbacks between water resources development and biophysical and socioeconomic sub-systems. Results suggest that infrastructural improvements, rigorous water demand management (e.g., replacing high water demand crops such as rice, corn, and alfalfa), and ecosystem-based regulatory prioritization, complemented by supply augmentation can temporarily alleviate water stress in a basin that is essentially governed by the Limits to Growth archetype

Multiple water sources and the physiographic heterogeneity of glacierized catchments hamper a complete conceptualization of runoff response to meltwater dynamics. In this study, we used environmental tracers (stable isotopes of water and electrical conductivity) to obtain new insight into the hydrology of glacierized catchments, using the Saldur River catchment, Italian Alps, as a pilot site. We analysed the controls on the spatial and temporal patterns of the tracer signature in the main stream, its selected tributaries, shallow groundwater, snowmelt and glacier melt over a 3-year period. We found that stream water electrical conductivity and isotopic composition showed consistent patterns in snowmelt-dominated periods, whereas the streamflow contribution of glacier melt altered the correlations between the two tracers. By applying two- and three-component mixing models, we quantified the seasonally variable proportion of groundwater, snowmelt and glacier melt at different locations along the stream. We provided four model scenarios based on different tracer signatures of the end-members; the highest contributions of snowmelt to streamflow occurred in late spring–early summer and ranged between 70 and 79 %, according to different scenarios, whereas the largest inputs by glacier melt were observed in mid-summer, and ranged between 57 and 69 %. In addition to the identification of the main sources of uncertainty, we demonstrated how a careful sampling design is critical in order to avoid underestimation of the meltwater component in streamflow. The results of this study supported the development of a conceptual model of streamflow response to meltwater dynamics in the Saldur catchment, which is likely valid for other glacierized catchments worldwide.

Snowmelt from the Tianshan Mountains (TS) is a major contributor to the water resources of the Central Asian region. Thus, changes in snow phenology over the TS have significant implications for regional water supplies and ecosystem services. However, the characteristics of changes in snow phenology and their influences on the climate are poorly understood throughout the entire TS due to the lack of in situ observations, limitations of optical remote sensing due to clouds, and decentralized political landscapes. Using passive microwave remote sensing snow data from 1979 to 2016 across the TS, this study investigates the spatiotemporal variations of snow phenology and their attributes and implications. The results show that the mean snow onset day (Do), snow end day (De), snow cover duration days (Dd), and maximum snow depth (SDmax) from 1979 to 2016 were the 78.2nd day of hydrological year (DOY), 222.4th DOY, 146.2 days, and 16.1 cm over the TS, respectively. Dd exhibited a spatial distribution of days with a temperature of

Real-time availability of satellite-based precipitation products gives the hydrologic prediction community an opportunity to enhance hydrologic prediction for a watershed or river basin. In the present study, the latest tropical rainfall-measuring mission (TRMM) multisatellite precipitation analysis (TMPA) research product, 3B42V7, was assessed against a gauge-based Indian Meteorological Department (IMD) gauge-based gridded data set using statistical and contingency table methods for an agricultural watershed in India. A comparative analysis of the TRMM and IMD data sets was carried out on daily, monthly, seasonal, and yearly bases for 16years (1998-2013). The analysis revealed that the TRMM data set performed reasonably well but showed significant biases. Although it underestimated watershed-averaged daily precipitation (bias=-28.65%, correlation coefficient=0.42), its results improved for monthly precipitation (bias=-26.17%, correlation coefficient=0.86). Moreover, its rainfall detection capability was determined to be better during the monsoon season than during the nonmonsoon season. In all timescales, however, it usually underestimated heavy rains. The utility of the TRMM precipitation data set in hydrologic modeling was evaluated via the semidistributed soil and water assessment tool (SWAT) hydrologic model. Using the IMD gauged data-calibrated SWAT model, TRMM data set-based simulation showed limited hydrologic prediction on a daily scale, whereas its prediction capability was fairly good on a monthly scale. The SWAT model exhibited remarkable improvement in both daily and monthly simulation when recalibrated with TRMM precipitation data. However, when driven by IMD data, the model always performed better than its TRMM-driven counterpart. The analysis indicated that the use of the TRMM precipitation data set can be a compensating approach after suitable bias correction and that it has the potential for hydrologic prediction in data-sparse regions.

Although many recent studies have quantified the potential effects of climate change on water resource systems, the scientific community faces now the challenge of developing methods for assessing and selecting climate change adaptation options. This paper presents a method for assessing impacts and adaptation strategies to global change in a river basin system at different temporal horizons using a hydro-economic model. First, a multiobjective analysis selects climate change projections based on the fitting of the climate models to the historical conditions for the historical period. Inflows for climate change scenarios are generated using calibrated rainfall-runoff models, perturbing observed meteorological time series according to the projected anomalies in mean and standard deviation. Demands are projected for the different scenarios and characterized using economic demand curves. With the new water resource and demand scenarios, the impact of global change on system performance is assessed using a hydro-economic model with reliability and economic indices. A new economic loss index is defined to assess the economic equity of the system. Selected adaptation strategies are simulated to compare performance with the business-as-usual scenario. The approach is applied to the Jucar River water resource system, in eastern Spain, using climate projections from the European Union (EU) ENSEMBLES project. Results show that the system is vulnerable to global change, especially over the long term, and that adaptation actions can save €3–65 million/year., Water Policy Center, Public Policy Institute of California, Estados Unidos, Instituto Universitario de Investigación de Ingeniería del Agua y Medio Ambiente, Universitat Politècnica de València, España, Unidad de Granada, Instituto Geológico y Minero de España, España

Since the 1990s, Indian farmers, supported by the government, have partially shifted from surface-water to groundwater irrigation in response to the uncertainty in surface-water availability. Water-management authorities only slowly began to consider sustainable use of groundwater resources as a prime concern. Now, a reliable integration of groundwater resources for water-allocation planning is needed to prevent aquifer overexploitation. Within the 11,000-km(2) Musi River sub-basin (South India), human interventions have dramatically impacted the hard-rock aquifers, with a water-table drop of 0.18 m/a over the period 1989-2004. A fully distributed numerical groundwater model was successfully implemented at catchment scale. The model allowed two distinct conceptualizations of groundwater availability to be quantified: one that was linked to easily quantified fluxes, and one that was more expressive of long-term sustainability by taking account of all sources and sinks. Simulations showed that the latter implied 13 % less available groundwater for exploitation than did the former. In turn, this has major implications for the existing water-allocation modelling framework used to guide decision makers and water-resources managers worldwide.

Snow cover mapping is important for snow and glacier-related research. The spatial and temporal distribution of snow cover area is a fundamental input to the atmospheric models, snowmelt runoff models and climate models, as well as other applications. Daily snow cover maps from Moderate Resolution Imaging Spectroradiometer (MODIS) Terra satellite were retrieved for the period between 2004 and 2007, and pixels in these images were classified as cloud, snow or snow-free. These images have then been compared with ground snow depth (SD) measurements from the four observatories located at different parts of Himalayas. Comparison of snow maps with in situ data showed good agreement with overall accuracies in between 78.15 and 95.60%. When snow cover was less, MODIS data were found to be less accurate in mapping snow cover region. As the SD increases, the accuracy of MODIS snow cover maps also increases.

Knowledge of current vegetation dynamics and an ability to make accurate predictions of ecological changes are essential for minimizing food scarcity in developing countries. Vegetation trends are also closely related to sustainability issues, such as management of conservation areas and wildlife habitats. In this study, AVHRR and MODIS NDVI datasets have been used to assess the spatial temporal dynamics of vegetation greenness in Rwanda under the contrasting trends of precipitation, for the period starting from 1990 to 2014, and for the first growing season (season A). Based on regression analysis and the Hurst exponent index methods, we have investigated the spatial temporal characteristics and the interrelationships between vegetation greenness and precipitation in light of NDVI and gridded meteorological datasets. The findings revealed that the vegetation cover was characterized by an increasing trend of a maximum annual change rate of 0.043. The results also suggest that 81.3% of the country’s vegetation has improved throughout the study period, while 14.1% of the country’s vegetation degraded, from slight (7.5%) to substantial (6.6%) deterioration. Most pixels with severe degradation were found in Kigali city and the Eastern Province. The analysis of changes per vegetation type highlighted that five types of vegetation are seriously endangered: The “mosaic grassland/forest or shrubland” was severely degraded, followed by “sparse vegetation,” “grassland or woody vegetation regularly flooded on water logged soil,” “artificial surfaces” and “broadleaved forest regularly flooded.” The Hurst exponent results indicated that the vegetation trend was consistent, with a sustainable area percentage of 40.16%, unsustainable area of 1.67% and an unpredictable area of 58.17%. This study will provide government and local authorities with valuable information for improving efficiency in the recently targeted countrywide efforts of environmental protection and regeneration.

WOS: 000376443800003, The management of urban channel systems constitutes an important problem in most developing cities of the world. In this study, a deterministic approach was followed to obtain water-diversion function through development of a numerical model that includes main hydrological elements such as stream flow, groundwater flow with stream-aquifer interaction, and evapotranspiration. An application to the city of Eskisehir (Turkey) is presented. The city has an extending channel network lying on an alluvium plain. In developing the new diversion function, three main criteria were taken into consideration: (1) the conservation of ecosystem; (2) flood prevention; and (3) aquifer replenishment. As the aquifer is the main water resource in the basin, a total of 96 boreholes were drilled in the framework of two projects. From these borehole data, stratigraphy and the piezometric head distribution were obtained. The basin was modeled using MODFLOW under Ground-water Modeling System (GMS) software. For calibration of hydraulic conductivities, the parameter estimation model was used. Through steady-state analysis, flood-prone areas were determined. Transient simulations were performed over a period of 650 days covering both low and high flows. A computer code following an iterative procedure was written in order to integrate the diversion function into MODFLOW. Simulation results demonstrated that the proposed function was successful in satisfying all three criteria

This paper presents a basin scale analysis of the Nilufer River Basin of Turkey. where agricultural, urban, and environmental users compete for scarce water in an environment where climate change and food security present large and growing challenges. It presents results of a basin scale dynamic nonlinear programming model that addresses economic efficiency. climate change, and food security. Its approach can be applied to other water-stressed regions operating in environments of economic and hydrologic constraints on water use. Basin scale modeling approach provides a general framework for formulating water management policies, consistent with the principles underlying the European Union Water Framework Directive. Rio Grande Basin Initiative New Mexico State University Agricultural Experiment Station

To study the impact of future climatic changes on hydrology in the Kaidu River Basin in the Tianshan Mountains, two sets of future climatic data were used to force a well-calibrated hydrologic model: one is bias-corrected regional climate model (RCM) outputs for RCP4.5 and RCP8.5 future emission scenarios, and the other is simple climate change (SCC) with absolute temperature change of -1 similar to 6 degrees C and relative precipitation change of -20%similar to 60%. Results show the following: (1) temperature is likely to increase by 2.2 degrees C and 4.6 degrees C by the end of the 21st century under RCP4.5 and RCP8.5, respectively, while precipitation will increase by 2%similar to 24%, with a significant rise in the dry season and small change in the wet season; (2) flow will change by -1%similar to 20%, while evapotranspiration will increase by 2%similar to 24%; (3) flow increases almost linearly with precipitation, while its response to temperature depends on the magnitude of temperature change and flow decrease is significant when temperature increase is greater than 2 degrees C; (4) similar results were obtained for simulations with RCM outputs and with SCC for mild climate change conditions, while results were significantly different for intense climate change conditions.

© Author(s) 2014. Understanding runoff processes in a basin is of paramount importance for the effective planning and management of water resources, in particular in data-scarce regions such as the Upper Blue Nile. Hydrological models representing the underlying hydrological processes can predict river discharges from ungauged catchments and allow for an understanding of the rainfall-runoff processes in those catchments. In this paper, such a conceptual process-based hydrological model is developed and applied to the upper Gumara and Gilgel Abay catchments (both located within the Upper Blue Nile Basin, the Lake Tana sub-basin) to study the runoff mechanisms and rainfall-runoff processes in the basin. Topography is considered as a proxy for the variability of most of the catchment characteristics. We divided the catchments into different runoff production areas using topographic criteria. Impermeable surfaces (rock outcrops and hard soil pans, common in the Upper Blue Nile Basin) were considered separately in the conceptual model. Based on model results, it can be inferred that about 65% of the runoff appears in the form of interflow in the Gumara study catchment, and baseflow constitutes the larger proportion of runoff (44-48%) in the Gilgel Abay catchment. Direct runoff represents a smaller fraction of the runoff in both catchments (18-19% for the Gumara, and 20% for the Gilgel Abay) and most of this direct runoff is generated through infiltration excess runoff mechanism from the impermeable rocks or hard soil pans. The study reveals that the hillslopes are recharge areas (sources of interflow and deep percolation) and direct runoff as saturated excess flow prevails from the flat slope areas. Overall, the model study suggests that identifying the catchments into different runoff production areas based on topography and including the impermeable rocky areas separately in the modeling process mimics the rainfall-runoff process in the Upper Blue Nile Basin well and yields a useful result for operational management of water resources in this data-scarce region. ispartof: Hydrology and Earth System Sciences vol:18 issue:12 pages:5149-5167 status: published

Social learning took place largely outside the sphere of government and spurred substantial technological and institutional innovation. Unique patterns of networks, informal institutions and social learning environments delineate options for social learning that are more likely to succeed, to lead to implementation. The history of social learning on lake Mille Lacs showed that new formal institutions are not necessarily the best sites for social learning, and that forms of innovation and modes of learning cannot be separated. Interdependence and shared goals, and flexibility in role distribution appear as success factors. The diversity of learning sites in a community should not be understood as a problem, as an obstacle to central steering and education by government: it enables the community to adapt and survive.

Transhumance is a practice of nomadic pastoralism that was once common in Mediterranean Europe. This livestock-rearing system is associated with the maintenance of cultural landscapes and the delivery of a wide range of ecosystem services. Although transhumance is still practised in Spain on a small scale, its future is highly uncertain because of socioeconomic constraints and other drivers of change. A participatory scenario-planning exercise with 68 participants, including shepherds, decision-makers, veterinarians, environmental experts, intermediaries from the wool and meat markets, and researchers, was used to envision plausible futures for transhumance and to enlighten policy-making for the maintenance of this practice along the Conquense Drove Road, one of the largest foot-based transhumant social-ecological networks still in use in Spain. Specifically, the aims were to: (1) analyse the drivers influencing the future of transhumance, (2) depict the current situation of transhumance, (3) envision future scenarios for this activity, (4) analyse ecosystem services’ trade-offs between different scenarios and their effect on human wellbeing, and (5) provide some insights for policy-making related to the maintenance of transhumance. Four plausible future scenarios were built, each showing clear trade-offs in the delivery of 19 ecosystem services, such as food, fibre, ecological connectivity, soil fertility, air quality, fire prevention, cultural identity, local ecological knowledge and cultural exchanges, as well as the different dimensions of human wellbeing. As a result of the participatory process, nine management strategies were identified for the maintenance of transhumance. Priority was given to the implementation of payment schemes for ecosystem services, the enhancement of social capital among transhumants and institutional coordination, the improvement of product marketing, and the restoration and conservation of drove roads. Finally, the implications of the current reform of the Common Agricultural Policy in the European Union for the maintenance of transhumance are discussed.

In this paper, we analyse the effectiveness of flood management measures based on the concept known as retaining water in the landscape . The investigated measures include afforestation, micro-ponds and small-reservoirs. A comparative and model-based methodological approach has been developed and applied for three meso-scale catchments located in different European hydro-climatological regions: Poyo (184 km2) in the Spanish Mediterranean, Upper Iller (954 km2) in the German Alps and Kamp (621 km2) in Northeast-Austria representing the Continental hydroclimate. This comparative analysis has found general similarities in spite of the particular differences among studied areas. In general terms, the flood reduction through the concept of retaining water in the landscape depends on the following factors: the storage capacity increase in the catchment resulting from such measures, the characteristics of the rainfall event, the antecedent soil moisture condition and the spatial distribution of such flood management measures in the catchment. In general, our study has shown that, this concept is effective for small and medium events, but almost negligible for the largest and less frequent floods: this holds true for all different hydro-climatic regions, and with different landuse, soils and morphological settings., Most of this research was done within the ERANET-Crue project "Room for the River", which was sponsored by: Lebensministerium (Austria), Bundesministerium fur Bildung und Forschung (Germany) and Ministerio de Ciencia y Educacion (Spain). We would like to thank each basin authority and national weather agencies for providing the hydro-meteorological data. The authors would like to thank to the Editor Andreas Gunther and two anonymous referees for their valuable comments.

International audience; Total mercury (THg) and methylmercury (MeHg) concentrations were measured in the muscle of Arctic charr (Salvelinus alpinus) and in the water column of 4 lakes that are located in the French Alps. Watershed characteristics were determined (6 coverage classes) for each lake in order to evaluate the influence of watershed composition on mercury and methylmercury concentrations in fish muscle and in the water column. THg and MeHg concentrations in surface water were relatively low and similar among lakes and watershed characteristics play a major role in determining water column Hg and MeHg levels. THg muscle concentrations for fish with either a standardized length of 220 mm, a standardized age of 5 years or for individualuals did not exceed the 0.5 mg kg(-1) fish consumption advisory limit established for Hg by the World Health Organization (WHO, 1990). These relatively low THg concentrations can be explained by watershed characteristics, which lead to short Hg residence time in the water column, and also by the short trophic chain that is characteristic of mountain lakes. Growth rate did not seem to influence THg concentrations in fish muscles of these lakes and we observed no relationship between fish Hg concentrations and altitude. This study shows that in the French Alps, high altitude lakes have relatively low THg and MeHg concentrations in both the water column and in Arctic charr populations. Therefore, Hg does not appear to present a danger for local populations and the fishermen of these lakes.

The Lerma-Chapala basin exemplifies the challenges posed by basin closure, where surface water allocation mechanisms, lack of environmental flows and access to water are critical issues. Underlying these issues is a need for accurate water accounting that is transparent and publicly available. This paper describes basin closure in the Lerma-Chapala basin, and focuses on negotiation processes surrounding surface water allocation mechanisms. Although significant attempts have been made to achieve a ‘soft landing’, the basin is still faced with water over-exploitation, environmental degradation, and a complicated transition from centralized water management to one in which states and water users have a larger say.