Climate change is a threat to human societies and natural ecosystems, yet public opinion research finds that public awareness and concern vary greatly. Here, using an unprecedented survey of 119 countries, we determine the relative influence of socio-demographic characteristics, geography, perceived well-being, and beliefs on public climate change awareness and risk perceptions at national scales. Worldwide, educational attainment is the single strongest predictor of climate change awareness. Understanding the anthropogenic cause of climate change is the strongest predictor of climate change risk perceptions, particularly in Latin America and Europe, whereas perception of local temperature change is the strongest predictor in many African and Asian countries. However, other key factors associated with public awareness and risk perceptions highlight the need to develop tailored climate communication strategies for individual nations. The results suggest that improving basic education, climate literacy, and public understanding of the local dimensions of climate change are vital to public engagement and support for climate action.

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Analyses of past typhoons have suggested that global climate change may result in increases in the intensity of these episodic events and that the effects of typhoons on the biogeochemistry of aquatic ecosystems will also be strengthened. We collected a 2-year time series of phytoplankton responses, including chlorophyll-a concentration, primary production and turnover rate in the Fei-Tsui Reservoir, Taiwan, on the basis of five typhoons in 2011 and eight in 2012 (21 weeks affected). We found approximately a two-fold increase in phytoplankton responses during the typhoon period compared with the non-typhoon period. However, there were no consistent correlations between phytoplankton responses and typhoon disturbance and length of typhoon stay. Vertical distributions of phytoplankton responses indicated that the peak values of these responses occurred both during the typhoon periods and during the non-typhoon periods occurring between two typhoons. Moreover, the strongest correlations were found between euphotic depth-averaged phosphate and primary production and turnover rate. Combined effects on phytoplankton responses could explain at least 70% of the variability. The regulation of phytoplankton responses by multiple processes and interactions among factors that operate during each typhoon event may add complexity to the challenge of detecting typhoon-driven mechanisms in such ecosystems. the aquatic food web, because it serves as a food source for all aquatic organisms that do not perform photosynthesis. Moreover, vertical migrations, as well as the diversity, community structure and temporal dynamics of phytoplankton, are responsible for steep nutrient gradients across the thermocline.

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Climate change is expected to cause geographic redistributions of species. To the extent that species within assemblages have different niche requirements, assemblages may no longer remain intact and dis- and reassemble at current or new geographic locations. We explored how climate change projected by 2100 may transform the world's avian assemblages (characterized at a 110 km spatial grain) by modeling environmental niche-based changes to their dietary guild structure under 0, 500, and 2000 km-dispersal distances. We examined guild structure changes at coarse (primary, high-level, and mixed consumers) and fine (frugivores, nectarivores, insectivores, herbivores, granivores, scavengers, omnivores, and carnivores) ecological resolutions to determine whether or not geographic co-occurrence patterns among guilds were associated with the magnitude to which guilds are functionally resolved. Dietary guilds vary considerably in their global geographic prevalence, and under broad-scale niche-based redistribution of species, these are projected to change very heterogeneously. A nondispersal assumption results in the smallest projected changes to guild assemblages, but with significant losses for some regions and guilds, such as South American insectivores. Longer dispersal distances are projected to cause greater degrees of disassembly, and lead to greater homogenization of guild composition, especially in northern Asia and Africa. This arises because projected range gains and losses result in geographically heterogeneous patterns of guild compensation. Projected decreases especially of primary and mixed consumers most often are compensated by increases in high-level consumers, with increasing uncertainty about these outcomes as dispersal distance and degree of guild functional resolution increase. Further exploration into the consequences of these significant broad-scale ecological functional changes at the community or ecosystem level should be increasingly on the agenda for conservation science.

Abstract. Based on two summer spatio-temporal data sets obtained from the northern South China Sea shelf and basin, this study reveals contrasting relationships among bacterial production (BP), dissolved organic (DOC) and primary production (PP) in the transition zone from the neritic to the oceanic regions. Inside the mid-shelf (bottom depth < 100 m), where inorganic nutrient supplies from river discharge and internal waves were potentially abundant, BP, DOC and PP were positively intercorrelated, whereas these three measurements became uncorrelated in the oligotrophic outer shelf and slope. We suggest that the availability of limiting minerals could affect the couplings/decouplings between the source (i.e. phytoplankton) and sink (i.e. bacteria) of organic carbon, and thus DOC dynamics. DOC turnover times were homogeneously low (37-60 days) inside the midshelf area and then increased significantly to values > 100 days in the outer shelf, indicating that riverine (Pearl River) DOC might be more labile. The actual mechanism for this is unknown, but might relate to higher inorganic nutrient supply from river/terrestrial sources. The positive correlation of the BP / PP ratios vs. phosphate (and nitrate) concentrations in the inner shelf implies that if anthropogenic mineral loading keeps increasing in the foreseeable future, the near-shore zone may become more heterotrophic, rendering the system a stronger source of CO 2 .

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