De status van het rekeninstrumentarium STONE 2.0

Het STONE-ontwikkelingstraject is gestart in 1993 door Wageningen UR, RIVM en RIZA. STONE is ook een netwerk van deskundigen om als discussieplatform te dienen voor wetenschappers en gebruikers. Voorjaar 2001 is een nieuwe ruimtelijke schematisering van Nederland opgeleverd en zijn nieuwe modulen voor berekening van de gewasopname, denitrificatie en mineralisatie van organisch stof geomplementeerd. Dit resulteerde in STONE 2.0. STONE 2.0 genereert uitvoer voor 6405 unieke combinaties (voornamelijk van landgebruik, bodemtype en hydrologie) voor tiendaagse periodes tussen 1986 en 2000. Prognoses kunnen worden berekend tot het jaar 2100. Interpretatie van de resultaten is alleen geoorloofd voor grotere ruimtelijke eenheden (indicatief 250 kmr) en voor meerjarige gemiddelden van nutriëntconcentraties en -fluxen. De meest robuuste resultaten van STONE 2.0 zijn de nitraatgehalten in het bovenste grondwater en de mate van fosfaatverzadiging van de bodem, en met name de resultaten op nationale schaal. Toepassingsmogelijkheden van STONE 2.0 op het gebied van milieubeleid zijn groot. STONE wordt sinds najaar 2001 toegepast voor berekeningen ten behoeve van de evaluatie van het mestbeleid, voor de Milieubalans en Milieuverkenningen, voor rapportages aan de Europese Commissie, en voor rapportages aan diverse nationale en internationale commissies. Sinds juli 2001 is een intensief traject ingezet van aanvullende toetsing/onzekerheidsanalyse en documentatie/review van STONE 2.0

Nutrient and energy potential for sustainable biorefineries based on wastes of agrifood systems: two regional cases

The aim of our study is to identify business models and opportunities with corporate social responsibility(CSR) presented by biorefineries based on wastes and return flows of agrifood systems. Two regional cases are explored and methods for generalisation are developed

A modelling framework for the assessment of the impacts of alternative policy and management options on the sustainability of Finnish agrifood systems

Recently, a new project focussing on integrated assessment modelling of agrifood systems (IAM-Tools) has been launched at MTT Agrifood Research Finland to gather, evaluate, refine and develop these component models and to link tem in an IAM framework for Finnish conditions

Assessing the adaptive capacity of agriculture in the Netherlands to the impacts of climate change under different market and policy scenarios (AgriAdapt project).

The AgriAdapt project has developed methodologies that enable (a) the assessment of impacts, risks and resiliencies for agriculture under changes in climatic conditions but also under changes of other drivers (market, technology, policy, etc.) and (b) the evaluation of adaptation strategies at farm type and regional scale. The methodologies are applied to arable farming over Europe and in a more integrated way, to that in Flevoland, the Netherlands as the key case. The methodologies at European level include (a) Crop modelling and (b) Market modelling. The methodologies at regional level cover the following main areas: (a) Integrated sustainability assessment, (b) Development of scenarios of farm structural change towards 2050, (c) Calculation of crop yields for different scenarios in 2050 inclusive agro-climate calendars, and (d) Partial and fully integrated analysis of farming systems in 2050, inclusive the aggregation to the regional level. Results from the application of the different methodologies are presented here. For example, exploring future farming systems shows that the most important driving factors towards 2050 within the A1-W scenario with a globalized economy, are (a) the yield increase due to climate change, (b) the expected product price change and (c) the degree of innovation in crop productivity. The effects of climate change are projected to have a positive economic effect on arable farming

Nutrient emission models in environmental policy evaluation at different scales - experience from the Netherlands

A nutrient emission modelling system, called STONE, has been developed for the Netherlands. The approach of STONE and its use in evaluating environmental policies in the Netherlands are discussed. This specific approach is then compared with that of other nutrient emission modelling systems. Emphasis is put on both the scientific¿technical aspects and on the applications in quantifying environmental effects of policy interventions at different scales. Results from STONE show, for example, the areas in the Netherlands where maximally acceptable nitrate concentrations in groundwater may be exceeded in the future, the effectiveness of implemented or intended policy measures on nutrient emissions, and the advantage of its mechanistic, spatially distributed approach. Such a detailed modelling approach is shown to be required to take into account the strong and complex interacting effects of, e.g. nutrient supply, groundwater level and management on nutrient emissions

Climate change effects on plant growth, crop yield and livestock

A review is given of the state of knowledge in the field of assessing climate change impacts on agricultural crops and livestock. Starting from the basic processes controlling plant growth and development, the possible impacts and interactions of climatic and other biophysical variables in different agro-environments are highlighted. Qualitative and quantitative estimations of shifts in biomass production and water relations, inter-plant competition and crop species adaptability are discussed. Special attention is given to the problems encountered when scaling up physiological responses at the leaf and plant level to yield estimates at regional to global levels by using crop simulation models in combination with geo-referenced, agro-ecological databases. Some non-linear crop responses to environmental changes and their relations to adaptability and vulnerability of agro-ecosystems are discussed