37 research outputs found

    Assessing water ecosystem services for water resource management

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    AbstractEcosystem service concepts can offer a valuable approach for linking human and nature, and arguments for the conservation and restoration of natural ecosystems. Despite an increasing interest in the topic, the application of these concepts for water resource management has been hampered by the lack of practical definitions and methodologies. In this study we review and analyse the current literature and propose an approach for assessing and valuing ecosystem services in the context of water management. In particular, to study the link between multiple pressures, ecological status and delivery of ecosystem services in aquatic ecosystems under different scenarios of measures or future changes. This is of interest for the development of River Basin Management Plans under the EU Water Framework Directive. We provide a list of proxies/indicators of natural capacity, actual flow and social benefit for the biophysical assessment of the ecosystem services. We advocate the use of indicators of sustainability, combining information on capacity and flow of services. We also suggest methods for economic valuation of aquatic ecosystem for each service and spatial scale of application. We argue that biophysical assessment and economic valuation should be conducted jointly to account for the different values of ecosystem services (ecologic, social and economic) and to strengthen the recognition of human dependency on nature. The proposed approach can be used for assessing the benefits of conservation and restoration of aquatic ecosystems in the implementation of the EU water policy

    PRELIMINARY STUDY OF WATER INJECTION ON THE COMBUSTION AND EMISSIONS CHARACTERISTICS IN A HCCI ETHANOL ENGINE

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    Our dependence on fossil fuels coupled with concerns about harmful emissions have motivated researchers to look for renewable fuels that have clean combustion and for advanced combustion modes. In this context, homogeneous charge compression ignition (HCCI) is an emerging technology which offers an alternative to conventional spark ignition and compression ignition engines and can operate on renewable fuels. Low temperature combustion, which can result in low NOx emissions with high indicated efficiency, is the more important characteristic of this combustion mode. It’s main problem is the combustion timing control due to lack of direct ignition control, once HCCI flame initiation is based on charge thermal state. Thus, controlled auto-ignition (CAI) combustion mode has been proposed. Several methods were proposed for combustion phasing control, between them, the injection of water in the intake manifold. This work investigated the influence of water injection in the intake runner of an ethanol HCCI cylinder from a converted three-cylinder diesel generator set, in which two cylinders operated on conventional diesel combustion and one diesel cylinder provided recycled exhaust gas for the one cylinder running on ethanol HCCI combustion. The water injection was used to control the CA50 combustion parameter. The results show that water injection is an efficient strategy to control the combustion timing, since the reactivity of the mixture can be controlled. The results at 400 and 600 kPa of IMEP and 1800 rpm indicated a good combustion stability, high efficiency and low emissions characteristics. The highest indicated fuel conversion efficiency found was 36.9% for 600 kPa of IMEP and 8 CAD of CA50. However, for 200 kPa of IMEP the combustion was unstable, the indicated efficiency was deteriorated and indicted CO emissions was high

    Report on the main activities undertaken and preliminary findings emerging from research on the CGIAR Targeting Agricultural Innovations and Ecosystem Services in the northern Volta basin (TAI) project

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    The CGIAR Water, Land and Ecosystems research project on Targeting Agricultural Innovations and Ecosystem Services in the northern Volta basin (TAI) is a two year project (2014-2016) led by Bioversity International in collaboration with 11 institutes: CIAT, CIRAD, International Water Management Institute (IWMI), King’s College London (KCL), SNV World Burkina Faso (SNV), Stanford University, Stockholm Resilience Centre (SRC), University of Development Studies Ghana (UDS), University of Minnesota, University of Washington, and the World Agroforestry Institute. We are working with communities across Centre-Est Burkina Faso and Upper-East Ghana to gather empirical data, test research methodologies and co-develop knowledge on solutions to ecosystem service management challenges. Results from the project are still emerging and will continue to do so into 2017 as the team finish analysing the data and writing up their findings. This report presents the main activities accomplished and preliminary headline messages from the first 18 months of the project. Final results from the project will be made available in 2017 on the WLE website
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