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The current hot debate on biofuels calls for a balanced and realistic long-term strategy for biofuels. The REFUEL project provides several ingredients for such a strategy. Analyses in this project indicate that domestically produced biofuels can cover a significant share of EU fuel demand in the coming decades, with the EU-12 new member states and Ukraine as most promising regions. This potential can be realised with residual streams and on existing agricultural land, without conversion of e.g. nature reserves. Second generation biofuels are essential for the long-term success of biofuels due to their superior performance in many ways. But generally, the key challenge for the near future would be how to enhance the development of biofuels in a responsible way, i.e. stimulating the production chains with the best performance, and preventing negative impacts e.g., by paying careful attention to possible system impacts of biofuel production such as indirect land use changes and rising food prices. Finally, 2nd generation biofuels require specific policy: the precursor role of 1st generation is overrated, both in technical terms as well as in their role as market precursors. When it comes to synergies, 2nd generation biofuels might benefit more from other developments in the energy sector, such as initiatives in co-firing of biomass for (heat and) power, than from 1st generation biofuels, also because of the public resistance that the latter induce.

Europe's agricultural land (including Ukraine) comprise of 164 million hectares of cultivated land and 76 million hectares of permanent pasture. A “food first” paradigm was applied in the estimations of land potentially available for the production of biofuel feedstocks, without putting at risk food supply or nature conservation. Three land conversion scenarios were formulated: (i) A base scenario, that reflects developments under current policy settings and respects current trends in nature conservation and organic farming practices, by assuming moderate overall yield increases; (ii) an environment oriented scenario with higher emphasis on sustainable farming practices and maintenance of biodiversity; and (iii) an energy oriented scenario considering more substantial land use conversions including the use of pasture land. By 2030 some 44–53 million hectares of cultivated land could be used for bioenergy feedstock production. The energy oriented scenario includes an extra 19 million hectares pasture land for feedstocks for second-generation biofuel production chains. Available land is foremost to be found in Eastern Europe, where substantial cultivated areas can be freed up through sustainable gains in yield in the food and feed sector. Agricultural residues of food and feed crops may provide an additional source for biofuel production. When assuming that up to 50% of crop residues can be used without risks for agricultural sustainability, we estimate that up to 246 Mt agricultural residues could be available for biofuel production, comparable to feedstock plantations of some 15–20 million hectares

A successful mid-term development of biofuels calls for a robust road map. REFUEL assesses inter alia least-cost biofuel chain options, their benefits, outlines the technological, legislative and other developments that should take place, and evaluate different policy strategies for realisation. Based on preliminary results some preliminary conclusions of the project are discussed here. There is a significant domestic land potential for energy crops in the EU, which could supply between one quarter and one third of gasoline and diesel demand by 2030 if converted into advanced biofuels. A biomass supply of 8 to 10 EJ of primary energy could be available at costs around or below 3 €/GJ. However, the introduction of advanced biofuel options may meet a considerable introductory cost barrier, which will not be overcome when EU policy is oriented to the introduction of biofuels at least cost. Therefore, conventional biodiesel and ethanol may dominate the market for decades to come, unless biofuels incentives are differentiated, e.g. on the basis of the differences in greenhouse gas performance among biofuels. The introduction of advanced biofuels may also be enhanced by creating stepping stones or searching introduction synergies. A stepping stone can be the shortterm development of lignocellulosic biomass supply chains for power generation by cofiring; synergies can be found between advanced FT-diesel production and hydrogen production for the fuel cell., Proceedings from the Annual Transport Conference at Aalborg University, Vol. 1 Núm. 1 (2007): Proceedings from the Annual Transport Conference at Aalborg University

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Beijing and Shanghai are among those Chinese cities that have experienced substantial growth over the past decades. We analyze historic urban growth patterns in Beijing and Shanghai using detailed land use maps from different time points. For Beijing digital land use data are available for 1982, 1992 and 1997 with a scale of 1:100,000. In the case of Shanghai we use high-resolution data derived from earth observation for the years 1967, 1989 and 1999. With the implementation of economic reform and opening policy China introduced urban land reforms invoking major changes in urban growth dynamics. A conceptual framework of urban growth mechanisms in the Chinese context is presented. It includes driving forces and constraint factors and four mechanism of urban land conversion, namely administrative allocation, urban land market, unauthorized ("black") land market and land development for Town and Village Enterprises (TVEs). In Beijing industrial land expansion has been the dominant factor of urban growth. Land expansion for TVEs here is of particular importance. There are major divergences of actual urban growth patterns and those envisaged by development plans of the city. In Shanghai residential land increased significantly mostly at the expense of cultivated area. Road development was substantial. The high resolution of the land use data allows to present detailed land use conversion patterns.

Over the past twenty years, the term agro-ecological zones methodology (AEZ) has become widely used for global regional and national assessments of agricultural potentials. The AEZ methodologies and procedures have recently been extended and newly implemented to make use of the latest digital geographical databases, and to cope with the specific characteristics of seasonal temperate and boreal climates. This report presents details of a companion model of AEZ that enables assessments of potential productivity of forest tree species. It is referred to a FAEZ. The FAEZ methodology follows an environmental approach; it provides a standardized framework for the characterization of climate, soil and terrain conditions relevant to forest production and it uses environmental matching procedures to identify limitations of prevailing climate, soil and terrain for a range of tree species and assumed management objectives. The model for the estimation of biomass increments is based on two well established and robust models: the Chapman-Richard biomass increment model, and the AEZ potential biomass model. FAEZ includes an inventory of ecological adaptability characteristics as well as an inventory of specific ecological and environmental requirements for 52 boreal and temperate forest tree species. The natural resources inventory is based on the up-to-date LUC-GIS database of climate, soil, terrain and vegetation covering China, Mongolia and former Soviet Union. Results of potential productivity for tree species in North, Central and East Asia are presented under three different sets of assumptions of forest resources management and exploitation, namely: conservation forestry, traditional production forestry and biomass plantation forestry.

Wide climatic variability is characteristic for large parts of China including events of extreme anomalies. This paper presents a time series covering the period 1958 to 1988 for monthly temperature and precipitation in China for a 5x5 km grid cell size. Monthly station histories (265 for temperature and 310 for rainfall), long-term averages of mean monthly temperature and rainfall on a 5 km grid, and a digital elevation mode (DEM) are the input data used to build the time series data base. Individual station anomalies in terms of deviation from the 31-year average were calculated and interpolated throughout China using the Mollifier interpolation technique. It uses a statistical approach to non-parametric interpolation. As a result data is available for monthly anomaly surfaces for all the years. By linking these to the long-term average grid maps we derive a time series of temperature and rainfall for China. Maps were produced for anomalies, and for absolute temperature and precipitation in each year between 1958 and 1988. Along with maps indicating variability at the stations, others have been completed based on the interpolated time series. Due to surface smoothing of the interpolation the variability of the interpolated time series is usually lower than the one based upon station observations. Temperature variability is quite low during the summer half. Anomalies are mostly less than 2 C in nearly all of China. During the winter months the anomaly increases up to 6 C with the highest variability in modern China and on the plateau. the pattern of monthly anomalies is stable in that relatively large areas show the same trend of deviation. Variability of rainfall shows large differences in spatial and temporal terms. Rainfall variability is highest during winter when rainfall is low. Especially the monthly data offer a comprehensive insight into seasonal differences in regional rainfall variability. In northern China's agricultural productive areas variability is high during the spring months, decreases in summer and increases as of September. In the middle and lower reaches of the Changjiang river basin variability is high in July and August amounting to as much as over 50%. Variability is relatively low in Southwest China, which includes the fertile Sichuan basin. Also in China's northeastern agricultural areas variability is relatively low during the growing season. From a policy point of view it is also of interest to aggregate the data for certain geographic regions. Results for provinces and major watersheds are presented. The interpolated surfaces are validated by comparing them with the station observations available in this study. Anomaly surfaces validation is determined by the interpolation error. There is a good fit for temperature anomaly surfaces compared to observed station anomalies. Because of the high spatial variability of rainfall anomalies including the possibility of extreme events in selected stations, interpolated anomalies are usually reduced during the interpolation. The temperature and rainfall time series validation is, in addition by the interpolation error, influenced by the differences in the 31-year average observed at the stations and the average presented in the long-term average grids to which the anomaly surfaces are linked.

This paper aims to identify land cover changes of the western part of the Horqin steppe by means of Landsat MSS satellite data. The Horqin steppe is located in the temperate semi-arid zone of North China, Inner Mongolia Autonomous Region. The steppe is considered to be one of the most drastic examples of land degradation in China's semi-arid region. Two Landsat MSS scenes, one for the year 1975, the other for 1989, with an overlapping area of around 20000 km2 were used for the land cover change detection. After performing geometric and radiometric corrections, an unsupervised cluster classification revealed six major land cover classes including water. Then a supervised Maximum Likelihood classification was applied to both scenes using the results from the unsupervised classification as well as the Horqin desertification/land use map (Lanzhou Institute of Desert Research, 1991) and filed data, which have been collected in September 1996. 5-10 training areas for each class where identified for the five land cover classes: (1) Moving sand with less than 10% vegetation cover, (2) farmland, (3) grassland with a vegetation cover of 10-60%, (4) grassland with a vegetation cover of 60-100% and (5) scrub forest. Further a post classification filtering process was applied to produce more homogenous areas. Finally by means of visual interpretation and a digital elevation model obvious misclassifications, such as overrepresentation of cropland at the expense of scrub forest or grassland with vegetation cover >60%, were changed. A comparison of the 1989 image classification with the collected field data gave poor results. Most likely this is due to the time difference between image acquisition and field data but also the result of low precision when georeferencing the image. Another source of error could be the actual sampling method, which has occurred close to river systems, where land use and land cover may undergo rapid changes. Comparing the 1975 and 1989 final classifications three main types of changes may be observed. First, larger areas of farmland are found in the 1989 image compared to 1975, mainly distributed around the Xiliao River system. Second a significant area of the class `grassland with 10-60% vegetation cover' in 1975 has become converted to the class `grassland 60-100% vegetation cover' by 1989. Third, sandy surfaces with the lowest vegetation cover

The study presented in this paper is part of the Regional Material Balance Approaches to Long-Term Environmental Policy Planning Project at IIASA. This project aims to study the flow of four heavy metals (cadmium, zinc, lead, and arsenic) with particular focus on soils. The combination of load, soil characteristics, land use, and land management, including plant types grown and agrochemical applications, determines the fate of stored heavy metals. Heavy metals may further accumulate in the soil or they may be remobilized and enter the food chain via plant uptake or via groundwater. Land use and land management have an impact on the load of heavy metals because certain agrochemical inputs (phosphate fertilizers, sewage sludge, manure) contain heavy metals as impurities. Certain land-management practices also influence the soil characteristics that determine whether heavy metals accumulate or are available in their mobile form. Three land-use scenarios have been developed to help assess possible effects of accumulated heavy-metal pollution in the region. This paper describes these three scenarios, which were constructed for the period 1995-2050. Section 2 presents the factors that influence land-use development and describes historical land-use changes in Europe and the countries of the project area. Developments in the agricultural sector, which are considered to be of particular importance for land-use changes in the European context, are discussed in Section 3. The discussion includes recent developments in Poland, the Czech Republic, and Germany, but also trends in the Common Agricultural Policy (CAP) of the European Union (EU) and possible impacts of global agricultural markets on European agriculture. Section 4 presents a general introduction to scenario construction; introduces the goals and key questions for the three scenarios constructed for the project area of this study; and presents, discusses, and compares the three scenarios. Conclusions are presented in Section 5.

This report investigates effects of long term load of two heavy metals, cadmium and lead to agricultural soils for a project area in Central Europe. The time frame for the historic analysis is 1955 to 1994. The major source of lead is atmospheric deposition. In the case of cadmium, besides atmospheric deposition, agricultural activities, such as P-fertilizer and manuring, are additional sources of heavy metal input to agricultural soils. Extremely high depositions that were measured in a "hot spot" region in the project area are included in the analysis. A soil model is used to perform a quantitative analysis of potential accumulation or release of cumulative heavy metal loads. A GIS database enables us to undertake a regional analysis. Potential future risks are addressed in a scenario approach covering the time frame 1995 to 2050. For the majority of the project area there was no significant increase in cadmium and particularly lead soil concentration compared to background values and guidelines. The parts of the project area which had the highest cumulative cadmium deposition historic cadmium accumulation may be of concern. However these assessments related to long term suitability for agricultural food production depend on environmental criteria and the time frames taken into account. Locally, in hot spot areas, atmospheric deposition were and still are much higher and soil guideline values may be exceeded within 10 to 50 years. The cadmium mass balance for the project area covering the period 1955 to 1994 suggests that from the cumulative load of 3062t of cadmium (about two thirds from atmospheric deposition and one third from agricultural sources), one third is lost (836t) and two thirds are accumulated in the soil (2226t). Estimates of future atmospheric cadmium and lead deposition are low compared to historic depositions. Cumulative cadmium deposition during 1991 and 2010 is only 10 to 40% of the cumulative deposition during 1970 and 1990. The average lead deposition in 2010 is only 10% of the average deposition in the 70s or 80s. Due to declining pH-value, triggered by the abandonment of agricultural land and/or a conversion into forest in scenario 1, major releases of cadmium are expected. Even the maximum assumed deposition is not high enough to compensate cadmium loss due to declining pH-value. The extent of decrease depends mainly on the assumed initial concentration in 1994 because cumulative future atmospheric deposition is very low compared to the cadmium already stored in the soils at present. Scenario 2 assumes intensive agricultural production until 2050. Agricultural activities are now the major source of cadmium load to the soils. In most cases a study state will be reached, the maximum delta increase over the future 55 years is 0.08mg/kg. In both scenarios lead soil concentrations are likely to decrease slightly in the future due to losses via erosion, which exceed atmospheric deposition.

This study identifies plausible scenarios for land use changes for a project area located at the coexistent borders of Poland, the Czech Republic and East Germany. The time frame is 1992 to 2050 with an intermediate step in 2020. The basis for the scenarios is an analysis of the driving forces for land use change in the context of the study area. The main emphasis here is on the EU's Common Agricultural Policy and trends in agriculture and forestry in the three countries of the project area. In addition former land use change, spread of urban areas, the state of mining areas, recreation and nature conservation and policies related to land use planning are of importance and therefore analyzed for each country. The direction of land use change between 1960 and present was a decrease in agricultural land and an increase in forest and 'other' area, which mainly consists of urban area and area for infrastructure. Recent changes in the Common Agricultural Policy aim at reducing overproduction an cut spending in general. The prevailing tendency is to liberalize the agricultural sector to shift from product tied payments to direct payments to farmers for social, environmental or cultural duties. Since the political changes in 1989 the three countries of the project area have undergone significant economic and structural changes. East Germany as part of Unified Germany and part of the EU has experienced the most drastic restructuring of the agricultural sector with the main feature of major job losses and production decreases, especially in the livestock sector. Similar developments, though not as radical, can be observed in Poland and the Czech Republic. The first Scenario, "Large Scale Increase of Wooded Area", anticipates the introduction of a free market economy to the agricultural sector. No more subsidies are required for agriculture. Large areas of marginal farmland have to be taken out of production. The price of land decreases. Farmers will either afforest their farmland or sell it to non-agricultural uses like urban development, recreation or nature conservation are options for farmers. A quantification for the project area foresees by 2050 a decrease of agricultural land to half of its size in 1992, a doubling of forest and an increase of 'other' area by 80%. Scenario 2, "Alternative Agricultural Products", assumes a shift from food production to nonfood products, mainly biofuel and incentives for an extensification of agricultural production. Subsidies, that are still required for the agricultural sector, will be kept. The overall policy aims at keeping the land open, avoiding uncontrolled spreading of urban development and providing prospect for development and employment in rural areas. The main characteristic of Scenario 3, "Europe as Food Exporter", is an increase in the demand for agricultural products, which by approximately 2010 triggers a increase in the world market price for food products. Reasons for this are population and wealth increase, especially in China an south east Asia, combined with environmental constraints like water or fertile land scarcity and erosion. As a result agricultural production in Europe becomes prosperous in the frame of a free market environment. No further subsidies are required for the sector. Until 2010 the development is similar to Scenario 2. Scenario 2 and 3 show only modest changes in land use patterns, but the agricultural production structure differs. Scenario 2 focuses on a mixture of food and non-food products, while in Scenario 3 all available farmland is used for food production after 2010.

This paper presents the results of an analysis on the total load of cadmium, zinc and lead to agricultural soils during the period 1955-1994. Total heavy metal load will serve as input for the soil modeling part of the wider IIASA study on "Regional Material Balance Approaches to Long Term Environmental Planning." The project area embraces the northwestern part of the Czech Republic (Bohemia and Morawia), southwestern Poland (Upper and Lower Silesia), and the south of the former G.D.R. (Sachsen, Sachsen-Anhalt, Brandenburg, Thueringen). Agricultural soils receive heavy metal via atmospheric deposition and via certain agricultural practices, the most important ones are: P-fertilizer application and manuring. Atmospheric deposition loads were derived from computations within the atmospheric modeling part of the IIASA IND Project. On the basis of a literature search focusing on the countries of the project area heavy metal concentration factors for P-fertilizer and manure were established. The fertilizer and manure application during the study period was derived from diverse statistical sources. The analysis shows the importance of regional differences and of the changes in time. This refers to both, the total load of heavy metals to the soils and the share of agricultural or atmospheric load in total load. The atmospheric load is highest in the 60s or 70s and then shows a downward trend. The highest P-fertilizer and manure application rates are in the 70s or 80s (and consequently the heavy metal load due to these practices is high). After the economic changes in 1989 there is a sharp decline in fertilizer application. The agricultural share in total load is very low in the case of lead, amounting to less than 10% during the whole period. Agricultural share in total load of cadmium and zinc varies considerable over time and shows high regional differences. For cadmium the agricultural share in total load ranges between 10 and 60 percent, in the case of zinc between 30 and 80 percent. A general feature here is, the higher the total load, the higher the share in atmospheric deposition. A preliminary mass balance for cadmium and lead in soils shows possible implications for long-term build up of heavy metals in soils. The release of Cadmium from soils via erosion and leaching contributes as so called diffuse load to total Cadmium load to rivers. The mass balance gives estimates for this diffuse load. Finally sources of uncertainties are discussed. They refer in particular to spatial variations that cannot be traced in this type of analysis. Close to major heavy metal emittents or in areas where uncontrolled sewage sludge application took place, the heavy metal load may be significantly higher than estimated in this study.