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 Miscanthus yields 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. Genotypespecific 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 r 2 5 0.84 compared with 0.64 for MISCANMOD, building confidence that the new model will be better able to predict Miscanthus yields 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.

European field experiments have demonstrated Miscanthus can 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 . In this paper, we have built on the previous studies by further developing a new Miscanthus crop growth model MIS-CANFOR 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 we show that 10% of arable land could produce 1709 PJ and mitigate 30 Tg of carbon dioxide-carbon (CO 2 -C) equivalent greenhouse gasses (GHGs) compared with EU27 primary energy consumption of 65 598 PJ, emitting 1048 Tg of CO 2 -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 Miscanthus is 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 CO 2 -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 CO 2 equivalent C GHG emissions.

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The downstream migrations of mature longfinned eels (Anguilla dieffenbachii Gray, 1842) and shortfinned eels (Anguilla australis Richardson, 1848) were investigated at Aniwhenua Dam on the Rangitaiki River between 1992 and 1998. Migrants were mostly females over 1000 mm total length (TL) with otoliths indicating rapid growth rates. Migrations, which occurred on a few nights each autumn, generally began once water temperatures began to decline and ended when temperatures dropped below c. 11 °C. Rainfall and flow increases were found to be key factors triggering migration events. Rainfall exceeding a cumulative total of 40 mm over 3 days accounted for 60% of migrant eels arriving at Aniwhenua. It is proposed that such rainfall triggers could be used as predictors to instigate mitigation activities that would allow mature eels to proceed uninjured past barriers such as hydro-electric dams.

Using bio-fuels, such as bio-ethanol or bio-diesel in transportation, or biomass in power generation reduces CO 2 emissions as the carbon is fixed by the plants from the atmosphere and saves the equivalent fossil fuel. The perennial rhizomatous C4 grass Miscanthus has one of the highest energy intensities per hectare of land in Europe. Here we model the future potential of Europe to produce Miscanthus with four different future land use and climate change scenarios and conclude that up to 17% of Europe's current primary energy consumption could be provided by this bio-energy crop by the year 2080 but that inter-annual variation of crop yield can be more than 20%. We conclude that that the highest greenhouse gas mitigation from bio-energy can be achieved by growing a Miscanthus crop on existing fertile and degraded arable land and not on land with a currently undisturbed ecosystem. Energy crops / biofuel / bioenergy / climate change / modeling: Miscanthus / Greenhouse gas emissions