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When heavy metal contaminated soils are excluded from food production, biomass crops offer an alternative commercial opportunity. Perennial crops have potential for phytoremediation. Whilst the conditions at heavy metal contaminated sites are challenging, successful phytoremediation would bring significant economic and social benefits. Seed-based Miscanthus hybrids were tested alongside the commercial clone Miscanthus × giganteus on arable land, contaminated with Pb, Cd and Zn near Katowice. Before the randomized experimental plots were established (25m2plots with plant density 2/m2) ‘time-zero’ soil samples were taken to determine initial levels of total (aqua regia) and bioavailable (CaCl2extraction) concentration of Pb, Cd and Zn. After the growing season plant material was sampled during autumn (October, green harvest) and winter (March, brown harvest) to determine differences in heavy metal uptake. Results after the first growing season are presented, including the plot establishment success, biomass yield and heavy metal uptake.

European field experiments have demonstrated Miscanthuscan produce some of the highest energy yields per hectare of all potential energy crops. Previous modelling studies using MISCANMOD have calculated the potential energy yield for the EU27 from mean historical climate data (1960–1990). In this paper, we have built on the previous studies by further developing a new Miscanthuscrop growth model MISCANFOR in order to analyse (i) interannual variation in yields for past and future climates, (ii) genotype‐specific parameters on yield in Europe. Under recent climatic conditions (1960–1990) we show that 10% of arable land could produce 1709 PJ and mitigate 30 Tg of carbon dioxide‐carbon (CO2‐C) equivalent greenhouse gasses (GHGs) compared with EU27 primary energy consumption of 65 598 PJ, emitting 1048 Tg of CO2‐C equivalent GHGs in 2005. If we continue to use the clone Miscanthus×giganteus, MISCANFOR shows that, as climate change reduces in‐season water availability, energy production and carbon mitigation could fall 80% by 2080 for the Intergovernmental Panel on Climate Change A2 scenario. However, because Miscanthusis found in a huge range of climates in Asia, we propose that new hybrids will incorporate genes conferring superior drought and frost tolerance. Using parameters from characterized germplasm, we calculate energy production could increase from present levels by 88% (to 2360 PJ) and mitigate 42 Tg of CO2‐C equivalent using 10% arable land for the 2080 mid‐range A2 scenario. This is equivalent to 3.6% of 2005 EU27 primary energy consumption and 4.0% of total CO2equivalent C GHG emissions.

Miscanthus×giganteus(Greef et Deu.), a perennial rhizomatous grass, native of SE Asia, has been trialed Europe‐wide as a potential bio‐energy crop. Plant growth models have been developed to match previously reported field experiments. These models have been used to extrapolate Miscanthusyields to other environments. Although the models use similar process descriptions, the parameters used to match the experimental data vary from site to site. This paper describes the development of universal process descriptions that use genotype‐specific parameters to predict yields in a wide range of environments. Using these, we develop a new model, MISCANFOR, from an existing model MISCANMOD by improving process descriptions for light interception by the canopy and the impact of temperature and water stress on radiation use efficiency. Genotype‐specific process descriptions for plant growth phase, photo‐period sensitivity, thermal time, temperature dependant radiation‐use efficiency, drought and frost kill predictions, nutrient repartition to the rhizome, and moisture content at harvest are added. Predictions made with MISCANFOR are compared with MISCANMOD for 36 experimental data sets for a wide variety of soils and climatic conditions in Europe. MISCANFOR matches field experiments with an r2=0.84 compared with 0.64 for MISCANMOD, building confidence that the new model will be better able to predict Miscanthusyields for other areas and future IPCC climate scenarios. This model has identified photoperiod sensitivity in addition to drought resistance and frost tolerance as parameters for crop improvement to extend the range of climatic conditions under which this crop can be grown economically.

Miscanthusis a genus of high‐yielding perennial rhizomatous grasses with C4photosynthesis. Extensive field trials of Miscanthusspp. biomass production in Europe during the past decade have shown several limitations of the most widely planted clone, M. × giganteusGreef et Deu. A 3‐yr study was conducted at five sites in Europe (Sweden, Denmark, England, Germany, and Portugal) to evaluate adaptation and biomass production potential of four acquisitions of M. × giganteus(No. 1–4) and 11 other genotypes, including M. sacchariflorus(Maxim.) Benth. (No. 5), M. sinensisAndersson (No. 11–15), and hybrids (No. 6–10). At each site, three randomized blocks containing a 5‐ by 5‐m plot of each genotype were established (except in Portugal where there were two blocks) with micropropagated plants at 2 plants m−2. In Sweden and Denmark, only M. sinensisand its hybrids satisfactorily survived the first winter following planting. Mean annual yields across all sites for all surviving genotypes increased each year from 2 t ha−1dry matter following the first year of growth to 9 and 18 t ha−1following the second and third year, respectively. Highest autumn yields at sites in Sweden, Denmark, England, and Germany were 24.7 (M. sinensishybrid no. 8), 18.2 (M. sinensishybrid no. 10), 18.7 (M. × giganteusno. 3), and 29.1 t ha−1(M. × giganteusno. 4), respectively. In Portugal, where irrigation was used, the top‐yielding genotype produced 40.9 t ha−1dry matter (M. sinensishybrid no. 7). Highest‐yielding genotypes in Sweden and Denmark were among the lowest yielding in Portugal and Germany, demonstrating strong genotype × environment interactions.

We improved a process‐oriented biogeochemical model of carbon and nitrogen cycling in grasslands and tested it against in situ measurements of biomass and CO2and CH4fluxes at five European grassland sites. The new version of the model (PASIM) calculates the growth and senescence of aboveground vegetation biomass accounting for sporadic removals when the grassland is cut and for continuous removals when it is grazed. Limitations induced by high leaf area index (LAI), soil water deficits and aging of leaves are also included. We added to this a simple empirical formulation to account for the detrimental impact on vegetation of trampling and excreta by grazing animals. Finally, a more realistic methane emission module than is currently used was introduced on the basis of the quality of the animals' diet. Evaluation of this improved version of PASIM is performed at (1) Laqueuille, France, on grassland continuously grazed by cattle with two plots of intensive and extensive grazing intensities, (2) Oensingen, Switzerland, on cut grassland with two fertilized and nonfertilized plots, and (3) Carlow, Ireland, on grassland that is both cut and grazed by cattle during the growing season. In addition, we compared the modeled animal CH4emissions with in situ measurements on cattle for two grazing intensities at the grazed grassland site of Laqueuille. Altogether, when all improvements to the PASIM model are included, we found that the new parameterizations resulted into a better fit to the observed seasonal cycle of biomass and of measured CO2and CH4fluxes. However, the large uncertainties in measurements of biomass and LAI make simulation of biomass dynamics difficult to make. Also simulations for cut grassland are better than for grazed swards. This work paves the way for simulating greenhouse gas fluxes over grasslands in a spatially explicit manner, in order to quantify and understand the past, present and future role of grasslands in the greenhouse gas budget of the European continent.