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Water quality improvements from afforestation in an agricultural catchment in Denmark illustrated with the INCA model
A. Bastrup-Birk,P. Gundersen
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2004,
Abstract: Intensive agricultural land use across Europe has altered nitrogen (N) budget of catchments substantially, causing widespread N pollution of freshwater. Although the N cycle in forests has changed due to increased N deposition, most forest soil waters in Europe have low nitrate concentrations. The protective function of forests on water quality has led to increasing interest in the planting of new forests on arable land as a measure to protect valuable or sensitive freshwater resources. The paper illustrates the effects of afforestation on water and N cycling using the Integrated Nitrogen Catchment (INCA) model. The model was calibrated on the Horndrup catchment in the eastern part of Jutland, Denmark, which is dominated by agricultural land use but also covered by 18% of forest land. The dynamics of nitrate concentrations in the stream water were simulated successfully by INCA over a three-year period. The simulation of the dynamics of nitrate concentrations in the soil water is closely linked to the simulation of the hydrological dynamics and especially to the rainfall. The best fit was achieved for both arable and forest land during the wettest year of the study period. The model was then used to simulate the effect of afforestation of a catchment dominated by agriculture on N fluxes with seepage and runoff. Scenarios of whole catchment conversion to forest were run, based on observations of evapotranspiration and N deposition from other Danish sites. The simulated conversion to mature forest reduced runoff by 30–45% and reduced the nitrate concentrations in the soil water by 50–70%. The simulated effect of afforestation on N leaching was an almost direct reflection of the change in the N input: substantial changes in the plant demand and soil N dynamics over the afforestation period were not simulated. To simulate the N dynamics over longer time-scales, appropriate for the study of afforestation, it is suggested that the INCA model be run with transient scenarios and linked to more detailed plant and soil models. Keywords: afforestation, arable land, forest hydrology, INCA, modelling, nitrogen, nitrate leaching
Aggregated Demand Response Modelling for Future Grid Scenarios  [PDF]
Hesamoddin Marzooghi,Gregor Verbic,David J. Hill
Mathematics , 2015, DOI: 10.1016/j.segan.2015.11.005
Abstract: With the increased penetration of intermittent renewable energy sources (RESs) in future grids (FGs), balancing between supply and demand will become more dependent on demand response (DR) and energy storage. Thus, FG feasibility studies will need to consider DR for modelling nett future demand. Against this backdrop, this paper proposes a demand model which integrates the aggregated effect of DR in a simplified representation of the effect of market/dispatch processes aiming at minimising the overall cost of supplying electrical energy. The conventional demand model in the optimisation formulation is augmented by including the aggregated effect of numerous users equipped with rooftop photovoltaic (PV)-storage systems. The proposed model is suited for system studies at higher voltage levels in which users are assumed to be price anticipators. As a case study, the effect of the demand model is studied on the load profile, balancing and loadability of the Australian National Electricity Market in 2020 with the increased penetration of RESs. The results are compared with the demand model in which users are assumed to be price takers.
Land Use Scenarios for Greater Copenhagen: Modelling the Impact of the Fingerplan  [PDF]
Christian FERTNER,Gertrud J?RGENSEN,Thomas Sick NIELSEN
Journal of Settlements and Spatial Planning , 2012,
Abstract: Urban planning and development in Denmark can be characterised by a relatively strong planning framework. Land use scenarios based on empirically derived dynamics of urban growth are practically never applied. However, modelling approaches do offer a methodology to explore the pressures in an urban region, as well as an approach to understand urban development patterns outside the ‘spatial masterplan’. In this context we will present the results of a modelling exercise addressing future land use change in the metropolitan area of Copenhagen, Denmark, and the impact of the current regional planning framework, the “Fingerplan 2007”. We test three policy scenarios and analyse different effects on urban growth by using the Metronamica model from the Dutch-based Research Institute for Knowledge Systems (RIKS). We analyse the possibilities to elaborate a practical and useful outcome within a relatively short period of time. The set-up and the results were discussed with a few experts from the Danish Ministry of the Environment and its value as discussion input recognized. The approach offers a lot of possibilities to discuss urban growth and spatial planning policies, even in a country with a strong planning framework as in Denmark.
Marco Antonio Conejero,Marcos Fava Neves,Mairun Junqueira Alves Pinto
Future Studies Research Journal : Trends and Strategies , 2010, DOI: 10.7444/future.v2i1.23
Abstract: Scenarios depicting targets concerning mandatory bio-fuel blending are critical to the strategic planning of food and bio-energy production chains and their design is the purpose of this paper. Each scenario tells a story about how various elements might interact under given conditions. The method herein utilized is primarily based on Schoemaker′s (1995) and Schwartz′s (1991) earlier proposals. A six step framework is followed: i) identify the focal issue; ii) summarize current mandatory blending targets; iii) identify the driving forces as of a macro-environmental analysis; iv) validate driving forces with specialists; v) rank such key forces by importance before uncertainties, building a correlation matrix; vi) design the scenarios. Finally, three alternative scenarios, relative to the adoption on behalf of countries, by the year 2020, of mandatory bio-fuel blending targets, are proposed which might guide these countries’ decision makers when planning production systems. Os cenários para as metas de adi o obrigatória de biocombustíveis s o uma parte importante do planejamento estratégico das cadeias produtivas de alimentos e bioenergia, sendo o seu desenho o objetivo desse artigo. Cada cenário conta uma história de como os vários elementos poderiam interagir sob certas condi es. O método usado aqui tem como base as contribui es anteriores de Schoemaker (1995) e Schwartz (1991). Uma seqüência de seis passos é seguida: i) identificar o foco de análise; ii) revisar as metas atuais de adi o obrigatória; iii) identificar os direcionadores com base em uma analise macro-ambiental; iv) validar os direcionadores com especialistas; v) priorizar tais for as motrizes em termos de importancia perante incertezas, construindo-se uma matriz de correla o; vi) desenhar os cenários. Ao final, s o propostos três cenários alternativos relacionados à ado o, por parte de países, até 2020, de metas de adi o obrigatória de biocombustíveis, que poder o orientar os tomadores de decis o dos mesmos durante o planejamento de sistemas de produ o.
Modelling scenarios of land use change in northern China in the next 50 years

HE Chunyang,LI Jinggang,SHI Peijun,CHEN Jin,PAN Yaozhong,LI Xiaobing,

地理学报 , 2005,
Abstract: Modelling scenarios of land use change and their impacts in typical regions are helpful to investigate the mechanism between land use and ecological systems and process the land use allocation under the ecological security. A system dynamics (SD) model with the aim to modelling scenarios of land use change and assessing ecological impact in northern China in the next 50 years is developed here. The accuracy assessment with the historic data from 1990 to 2001 indicated the SD model is robust. After the different "what-if" scenarios controlled by GDP, population, market, and technology advancement were built, the different scenarios of land use change in northern China from 2000 to 2050 were simulated with their ecological impact assessed. The result suggested that such factors as GDP, population, market and technology have a strong relationship with land use structural change in northern China. It also indicated that such measures as strict controlling of population increase, importing some food to keep the supply-demand balance in the region, and improving agricultural technology will be the guarantee of regional sustainable development with fast economic growth and the obvious land use structural improvement at the same time.
MOSES – A modelling tool for the analysis of scenarios of the European electricity supply system  [cached]
Weitemeyer S.,Feck T.,Agert C.
EPJ Web of Conferences , 2012, DOI: 10.1051/epjconf/20123301002
Abstract: Recent studies have shown that a transition of the current power supply system in Europe to a system almost entirely based on fluctuating Renewable Energy Sources (RES) by mid-century is possible. However, most of these scenarios require a significant amount of back-up power capacities to ensure the security of electricity supply. This would imply high additional investments and operating costs. Hence, alternative options should be investigated first. Here we present a first outlook of our simulation model MOSES which will be able to analyse different target states of the European electricity system in 2050. In this model long-term meteorological data series are used to optimise the capacity mix of RES in Europe. One of the main elements of our tool is a simplified electricity network. In addition, alternative options for reduction of additional back-up power like the expansion of the transmission grid, the use of demand-side management and/or the installation of over-capacities will be implemented. The results will be used to provide scientifically proven recommendations to policy makers for a reliable energy supply system in Europe based on Renewable Energy Sources.
A Broad Assessment of Factors Determining Culicoides imicola Abundance: Modelling the Present and Forecasting Its Future in Climate Change Scenarios  [PDF]
Pelayo Acevedo,Francisco Ruiz-Fons,Rosa Estrada,Ana Luz Márquez,Miguel Angel Miranda,Christian Gortázar,Javier Lucientes
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0014236
Abstract: Bluetongue (BT) is still present in Europe and the introduction of new serotypes from endemic areas in the African continent is a possible threat. Culicoides imicola remains one of the most relevant BT vectors in Spain and research on the environmental determinants driving its life cycle is key to preventing and controlling BT. Our aim was to improve our understanding of the biotic and abiotic determinants of C. imicola by modelling its present abundance, studying the spatial pattern of predicted abundance in relation to BT outbreaks, and investigating how the predicted current distribution and abundance patterns might change under future (2011–2040) scenarios of climate change according to the Intergovernmental Panel on Climate Change. C. imicola abundance data from the bluetongue national surveillance programme were modelled with spatial, topoclimatic, host and soil factors. The influence of these factors was further assessed by variation partitioning procedures. The predicted abundance of C. imicola was also projected to a future period. Variation partitioning demonstrated that the pure effect of host and topoclimate factors explained a high percentage (>80%) of the variation. The pure effect of soil followed in importance in explaining the abundance of C. imicola. A close link was confirmed between C. imicola abundance and BT outbreaks. To the best of our knowledge, this study is the first to consider wild and domestic hosts in predictive modelling for an arthropod vector. The main findings regarding the near future show that there is no evidence to suggest that there will be an important increase in the distribution range of C. imicola; this contrasts with an expected increase in abundance in the areas where it is already present in mainland Spain. What may be expected regarding the future scenario for orbiviruses in mainland Spain, is that higher predicted C. imicola abundance may significantly change the rate of transmission of orbiviruses.
Mathematical Constraints on Financially Viable Public Policy  [PDF]
Martin Gremm,Mark B. Wise
Quantitative Finance , 2012,
Abstract: Social Security and other public policies can be viewed as a series of cash in and outflows that depend on parameters such as the age distribution of the population and the retirement age. Given forecasts of these parameters, policies can be designed to be financially stable, i.e., to terminate with a zero balance. If reality deviates from the forecasts, policies normally terminate with a surplus or a deficit. We derive constraints on the cash flows of robust policies that terminate with zero balance even in the presence of forecasting errors. Social Security and most similar policies are not robust. We show that non-trivial robust policies exist and provide a recipe for constructing robust extensions of non-robust policies. An example illustrates our results.
Spatial Simulation Modelling of Future Forest Cover Change Scenarios in Luangprabang Province, Lao PDR  [PDF]
Courage Kamusoko,Katsumata Oono,Akihiro Nakazawa,Yukio Wada,Ryuji Nakada,Takahiro Hosokawa,Shunsuke Tomimura,Toru Furuya,Akitaka Iwata,Hiromichi Moriike,Takashi Someya,Takashi Yamase,Mitsuru Nasu,Yoshitaka Gomi,Takio Sano,Takao Isobe,Khamma Homsysavath
Forests , 2011, DOI: 10.3390/f2030707
Abstract: Taking Luangprabang province in Lao Peoples’s Democratic Republic (PDR) as an example, we simulated future forest cover changes under the business-as-usual (BAU), pessimistic and optimistic scenarios based on the Markov-cellular automata (MCA) model. We computed transition probabilities from satellite-derived forest cover maps (1993 and 2000) using the Markov chains, while the “weights of evidence” technique was used to generate transition potential maps. The initial forest cover map (1993), the transition potential maps and the 1993–2000 transition probabilities were used to calibrate the model. Forest cover simulations were then performed from 1993 to 2007 at an annual time-step. The simulated forest cover map for 2007 was compared to the observed (actual) forest cover map for 2007 in order to test the accuracy of the model. Following the successful calibration and validation, future forest cover changes were simulated up to 2014 under different scenarios. The MCA simulations under the BAU and pessimistic scenarios projected that current forest areas would decrease, whereas unstocked forest areas would increase in the future. Conversely, the optimistic scenario projected that current forest areas would increase in the future if strict forestry laws enforcing conservation in protected forest areas are implemented. The three simulation scenarios provide a very good case study for simulating future forest cover changes at the subnational level (Luangprabang province). Thus, the future simulated forest cover changes can possibly be used as a guideline to set reference scenarios as well as undertake REDD/REDD+ preparedness activities within the study area.
Determining agricultural land use scenarios in a mesoscale Bavarian watershed for modelling future water quality
B. B. Mehdi, R. Ludwig,B. Lehner
Advances in Geosciences (ADGEO) , 2012,
Abstract: Land use scenarios are of primordial importance when implementing a hydrological model for the purpose of determining the future quality of water in a watershed. This paper provides the background for researching potential agricultural land use changes that may take place in a mesoscale watershed, for water quality research, and describes why studying the farm scale is important. An on-going study in Bavaria examining the local drivers of change in land use is described.
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