Suchergebnisse

Abstract
Background
In Europe, ammonia (NH3) emissions strongly contribute to fine particulate matter (PM2.5) pollution and associated premature human mortality. The National Emission Ceilings Directive 2016/2284/EU has set an obligation for all European Union countries to reduce the NH3 emissions by 6%, relative to 2005, by 2020. This study aims to assess the costs and benefits of four NH3 emission abatement options for the compliance of the agricultural sector with the commitments of the European air quality regulatory framework. A regional atmospheric model (WRF/Chem) was used to assess the effects of regulating NH3 emissions reductions on PM2.5 concentrations over Europe. Non-market valuation techniques (value of statistical life) were used to monetize the associated health outcomes.

Results
We calculated that 16 out of the 28 EU member states exceeded their 2020 NH3 emission ceilings in 2016. The highest exceedances from the 2020 emission commitment level occurred in Latvia (15%), Germany (12%) and the UK (12%). Simulation of the required NH3 emission reduction by WRF/Chem showed that relatively large reductions in PM2.5 concentrations occur over central-western Europe and the UK. The largest health benefits (> 5% reduction in premature mortality) were found for Scandinavia. The economic benefit from avoided premature deaths over Europe amounts to 14,837 M€/year. The costs of four NH3 emission abatement options, where each would fully achieve the required emission reduction, range from 80 M€/year for low nitrogen feed to 3738 M€/year for low-emission animal housing, with covered manure storage (236 M€/year) and urea fertilizer application (253 M€/year), in between.

Conclusion
Our analysis indicates that the costs of compliance by the agricultural sector with the commitments of the European air quality regulations are much lower than the economic benefit. Thus, much more ambitious reduction commitments for NH3 emissions could be applied by the EU-28. The monetization of the health benefits of NH3 emission abatement policies and the assessment of the implementation costs can help policy-makers devise effective air pollution control programmes.

Abstract. Coupled atmospheric–hydrologic systems are increasingly used as instruments for flood forecasting and water management purposes, making the performance of the hydrologic routines a key indicator of the model functionality. This study's objectives were (i) to calibrate the one-way-coupled WRF-Hydro model for simulating extreme events in Cyprus with observed precipitation and (ii) to evaluate the model performance when forced with WRF-downscaled (1×1 km2) re-analysis precipitation data (ERA-Interim). This set-up resembles a realistic modelling chain for forecasting applications and climate projections. Streamflow was modelled during extreme rainfall events that occurred in January 1989 (calibration) and November 1994 (validation) over 22 mountain watersheds. In six watersheds, Nash–Sutcliffe efficiencies (NSEs) larger than 0.5 were obtained for both events. The WRF-modelled rainfall showed an average NSE of 0.83 for January 1989 and 0.49 for November 1994. Nevertheless, hydrologic simulations of the two events with the WRF-modelled rainfall and the calibrated WRF-Hydro returned negative streamflow NSE for 13 watersheds in January 1989 and for 18 watersheds in November 1994. These results indicate that small differences in amounts or shifts in time or space of modelled rainfall, in comparison with observed precipitation, can strongly modify the hydrologic response of small watersheds to extreme events. Thus, the calibration of WRF-Hydro for small watersheds depends on the availability of observed rainfall with high temporal and spatial resolution. However, the use of modelled precipitation input data will remain important for studying the effect of future extremes on flooding and water resources.

This article reviews work that had the objective of introducing agricultural technologies in a marginal dryland area, the Khanasser Valley, northwestern Syria. The highly variable rainfall is barely sufficient to support livelihoods in this traditional barley—livestock production system. The valley is representative of other marginal dryland areas in West Asia and North Africa. We used a farmer-participatory approach to evaluate the performance of agricultural technologies for dry marginal areas in terms of their contribution to livelihoods and effect on the environment. The integrated approach allowed comprehensively comparing and evaluating the viability of promising technologies, including novel crops, intercropping, soil management techniques, and livestock rearing. The results show that improved barley varieties, olives, cumin, and lamb fattening can improve livelihoods, particularly for the land-owning households, whereas other households can benefit indirectly in terms of employment spillovers. These options are also environmentally friendly and sustain the natural resource base.

Although several institutional and management approaches that address the degradation of the rangelands have been tested in the dry areas of Central and West Asia and North Africa (CWANA), impact has been limited. Nonetheless, the development of National Action Plans to combat desertification highlights the interest of governments to tackle this issue. Payment for Environmental Services (PES) may be a viable policy option, though, to date, most PES programs have focused on the management of different resources (forests, watersheds). The purpose of this paper is to examine whether PES could be a viable option to promote sustainable rangelands management in the dry rangelands of CWANA. Specifically, it focuses on the scientific gaps and knowledge related to the local and global environmental services produced by rangelands and addresses questions related to the beneficiaries of these services. Institutional conditions necessary for the implementation of such schemes are discussed. ; Non-PR ; IFPRI1; Theme 3; Managing natural resources; CAPRi ; EPTD