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This chapter presents current knowledge, methods, and applications of nutritional energetics in an aquaculture setting. All organisms ingest and metabolize macronutrients that supply dietary energy and the nutrients have different fates. The different aspects of energy flow from feed to fish or shrimp are similar to those known in land animals or birds, but the aquatic mode of life imposes challenges and confers advantages both at the cellular level and at the whole organism level. Energy gain and losses are governed by the efficiency with which the macronutrients are utilized. The application of net energy system as prevailing in monogastric land animal nutrition is also valid for aquatic organisms. The large number of species reared by aquaculture is a real challenge, but many of the basic principles are valid across species. There is a need for precisely quantifying the partition of dietary digestible energy for somatic growth, reproduction, and other physiological changes due to environmental factors.

Marine monitoring programs provide data that are essential for marine management. The reliability of such data is underpinned by proficiency tests. In the context of Quasimeme, a proficiency testing program for the marine environment, a statistical model has been developed in 2000 to evaluate data sets. The mathematical basis of this model has been reformulated in 2016. In this article, the new mathematical basis is concisely explained. The main results of a comparative study using five statistical procedures on about 2400 data sets are described. Examples of the application of the five techniques on two data sets with complicated distributions are given. It is concluded that the NDA implementation of our model offers the highest robustness and that a thorough evaluation should invoke graphical representations of the data sets and consider robust skewness and results from different statistical methods.

Energy crops are expected to provide a significant amount of biomass to achieve the European targets on renewable energy. Here we focus on switchgrass (Panicum virgatum L.) and Miscanthus (Miscanthus x giganteus Greef & Deuter) two rhizomatous perennial grasses which have received particular interest during the last decade as bioenergy crops. Although the two grasses have been recently investigated deeply in U.S.A. and Europe, a significant uncertainty still exists in literature on measured or predicted potential yields. In order to understand the role these species can play, a study was carried out aimed at collecting measured side by side data on Miscanthus and switchgrass yields across Europe. Biomass productivity of the two crops significantly varied depending on location, however the relative yield (RY), i.e. Miscanthus to switchgrass yields ratio, was rather constant across Europe (78% ± 9.2), thus indicating parallel yield variation by switchgrass and Miscanthus at different locations. By assessing RY a more reliable economic and LCA comparison and then choice among crops could be provided. Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 729-733

For the purpose of assessing flood hazard in the Upper Danube Basin in Central Europe under current and projected future climate conditions, we evaluated data from a recent experiment with the regional climate model HIRHAM at a horizontal resolution of approximately 12 km. The climate simulations were used to drive the hydrological model LISFLOOD and the results were compared with observations of precipitation and river discharge in the area. To explore the benefits of using these very high-resolution data, we also included the results of two HIRHAM experiments at a lower resolution of ∼50 km in our comparison. It was found that the 12-km data represent the orographic precipitation patterns and the extreme rainfall events over the Upper Danube Basin better than the low-resolution 50-km data. However, the average precipitation rates are generally higher than observed, while the extreme precipitation levels are mostly underestimated. Using the HIRHAM data as input into the LISFLOOD model resulted in a realistic simulation of the average discharge regime in the Upper Danube. In most rivers the 12-km data also led to a better representation of extreme discharge levels, although the performance was still poor in two relatively small rivers originating in the Alps. At larger spatial scales much of the differences and uncertainties between the high- and low-resolution climate data and the observations are averaged out, resulting in a more or less similar performance of the hydrological model, but at the local and sub-basin scale the 12-km data yield better results. The scenario simulations suggest that future climate changes will have an influence on the discharge regime and may increase the flood hazard in large parts of the Upper Danube Basin.

Recent research predicts that future climate change will result in substantial biodiversity loss associated with loss of habitat for species. However, the magnitude of the anticipated biodiversity impacts are less well known. Studies of species vulnerability to climate change through species distribution models are often limited to assessing the extent of species' exposure to the consequences of climate change to their local environment, neglecting species sensitivity to global change. The likelihood that species or populations will decline or go extinct due to climate change also depends on the general sensitivity and adaptive capacity of species. Hence, analyses should also obtain more accurate assessments of their vulnerability. We addressed this by constructing a vulnerability matrix for 180 bird species currently breeding in Subarctic and Arctic Europe that integrates a climatic exposure-based vulnerability index and a natural-history trait-based vulnerability index. Species that may need extra conservation attention based on our matrix include the Great Snipe (Gallinago media), the Rough-legged Buzzard (Buteo lagopus), the Red-throated Pipit (Anthus cervinus), the Common Swift (Apus apus), the Horned Lark (Eremophila alpestris), and the Bar-tailed Godwit (Limosa lapponica). Our vulnerability matrix stresses the importance of looking beyond exposure to climate change when species conservation is the aim. For the species that scored high in our matrix the future in the region looks grim and targeted conservation actions, incorporating macroecological and global perspectives, may be needed to alleviate severe population declines. We further demonstrate that climate change is predicted to significantly reduce the current breeding range of species adapted to cold climates in Subarctic and Arctic Europe. The number of incubation days and whether the species was a habitat specialist or not were also among the variables most strongly related to predicted contraction or expansion of species' breeding ranges. This approach may aid the identification of vulnerable bird species worldwide.

Academics and practitioners have responded to the gridlock in the international climate-change regime by more actively exploring the ability of individuals and/or groups of states to fill in the associated ‘governance gaps’ by engaging in policy innovation at the level of the nation state, including its regional and local emanations. Here, we draw together the findings of a collection that, for the first time, explores policy innovation at this level from three key perspectives: the source of new policy elements (‘invention’), their wider entry into use (‘diffusion’), and their projected and/or real effects (‘evaluation’). After critically reviewing the findings of the contributions from these perspectives, we explore new directions for definitional, conceptual-theoretical, and empirical work in this field. Finally, we explore how a more systematic analysis of policy innovation dynamics can inform a much fuller understanding of climate policy and governance across different sites and scales.

The Murray-Darling Basin is Australia's food bowl and home to many iconic water bodies that are culturally and ecologically highly valued. The recent Millennium Drought (from mid-1990s to 2009) was the most severe hydrological drought since records started in the late 19th century. It severely impacted on the basin and for many acted as a wake-up call. To address the ongoing declines in water resources and environmental conditions and to prepare the region for climate change, Australia's Governments are currently attempting to introduce a new comprehensive, and integrated approach to the management of the basin's water resources. In this paper, long-term time series of climate, hydrological and environmental data are used to analyze how compounding stresses have gradually affected the hydrological system and its services. Major hydroclimatic stresses considered in this paper include salinity, water use, droughts, and climate change. Other, more localized or minor stresses exist (groundwater extraction, farm dams, afforestation, bush fires, cyanobacterial blooms and pollutants) and are reviewed more briefly. The history of water policy and planning shows that Government actions have been strongly influential on the basin. A shift in the strategic goals from water development to the protection and restoration of environmental assets is noticeable since the mid 1990s. Median climate change projections by 2030 indicate smaller reductions in rainfall and runoff than those observed during the recent Millennium Drought, but have a relatively high uncertainty attached to them. The use of regional approaches to reduce that uncertainty, such as statistical downscaling, points to a sizeable decline in rainfall by the end of the century. Most climate projections used for planning consider greenhouse emission scenarios that have smaller global emission trends than the one observed over the last decade. Other, 'less optimistic' scenarios have to be considered for long-term water planning and food security. Compounding all these stresses, is the naturally high hydroclimatic variability of this semi-arid region, that may have been insufficiently considered during previous water development and planning efforts. Successful water planning will need to balance cultural and ecological values with food production, account for high natural variability and uncertainty in climate change projections, learn from past mistakes and be cognizant of future hydrological changes.

Safely achieving the goals of the Paris Climate Agreement requires a worldwide transformation to carbon-neutral societies within the next 30 y. Accelerated technological progress and policy implementations are required to deliver emissions reductions at rates sufficiently fast to avoid crossing dangerous tipping points in the Earth’s climate system. Here, we discuss and evaluate the potential of social tipping interventions (STIs) that can activate contagious processes of rapidly spreading technologies, behaviors, social norms, and structural reorganization within their functional domains that we refer to as social tipping elements (STEs). STEs are subdomains of the planetary socioeconomic system where the required disruptive change may take place and lead to a sufficiently fast reduction in anthropogenic greenhouse gas emissions. The results are based on online expert elicitation, a subsequent expert workshop, and a literature review. The STIs that could trigger the tipping of STE subsystems include 1) removing fossil-fuel subsidies and incentivizing decentralized energy generation (STE1, energy production and storage systems), 2) building carbon-neutral cities (STE2, human settlements), 3) divesting from assets linked to fossil fuels (STE3, financial markets), 4) revealing the moral implications of fossil fuels (STE4, norms and value systems), 5) strengthening climate education and engagement (STE5, education system), and 6) disclosing information on greenhouse gas emissions (STE6, information feedbacks). Our research reveals important areas of focus for larger-scale empirical and modeling efforts to better understand the potentials of harnessing social tipping dynamics for climate change mitigation.