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951.
Climate change is one of the greatest threats to humanity and requires immediate action. Schuldt, Konrath, and Schwarz (2011) suggested that beliefs in environmental phenomena can be influenced by the terminology used to describe it: changing question wording from global warming to climate change resulted in a 6.3 percentage point increase in belief in environmental phenomena. This association was moderated by political self-identification, with Republicans being 16.2 percentage points more likely to believe in climate change than in global warming, with Democrats showing no difference. The potential for connotative meanings to shift over time and the sociopolitical changes since the original study, potential policy and environmental campaign implications, and an expansion of these findings to other countries, motivated an attempt to replicate this important finding. This pre-registered study repeated the original procedures in the United States of America and two other countries (United Kingdom and Australia; total N = 5,717). Although question wording no longer had a significant effect on beliefs in climate change/global warming, the association of political self-identification with beliefs in environmental phenomena replicated in all three countries, with Conservatives consistently believing less in climate change/global warming than Liberals. The potential impacts of temporal and methodological differences on the discrepancies between this study's and the original's findings are discussed. 相似文献
952.
A two year survey of benthic primary production during periods of emersion was performed on two stations of an intertidal mudflat (a muddy-sand station and a muddy station) in the Seine Estuary (English Channel, France). The goals of this study were to investigate the seasonal variations of metabolism, to estimate daily potential primary production variation at the annual scale and to estimate the annual potential primary production of the mudflat. Primary production and respiration were estimated by in situ measurements of carbon dioxide fluxes. Chlorophyll a concentration exhibited a great variability on both locations. Gross community production ranged from ca. 0 to 77 mg C m(-2) h(-1) at the muddy-sand location and from ca. 0 to 122 mg C m(-2) h(-1) at the muddy location. Community respiration showed a seasonal trend following temperature variations (up to 28.51 mg C m(-2) h(-1) in the muddy-sand and up to 23.40 mg C m(-2) h(-1) in the mud). Daily potential primary production was calculated, according to seasonal variations of photosynthetic parameters calculated using three photosynthesis versus irradiance curves obtained for the muddy location. The annual gross community primary production was 135 g C m(-2) yr(-1), leading to a low autotrophic annual budget, considering an annual community respiration of 110 g C m(-2) yr(-1). 相似文献
953.
Chemically unusual ground water can provide an environment for novel communities of bacteria to develop. Here, we describe a diverse microbial community that inhabits extremely alkaline (pH > 12) ground water from the Lake Calumet area of Chicago, Illinois, where historic dumping of steel slag has filled in a wetland. Using microbial 16S ribosomal ribonucleic acid gene sequencing and microcosm experiments, we confirmed the presence and growth of a variety of alkaliphilic beta-Proteobacteria, Bacillus, and Clostridium species at pH up to 13.2. Many of the bacterial sequences most closely matched those of other alkaliphiles found in more moderately alkaline water around the world. Oxidation of dihydrogen produced by reaction of water with steel slag is likely a primary energy source to the community. The widespread occurrence of iron-oxidizing bacteria suggests that reduced iron serves as an additional energy source. These results extend upward the known range of pH tolerance for a microbial community by as much as 2 pH units. The community may provide a source of novel microbes and enzymes that can be exploited under alkaline conditions. 相似文献
954.
Stream-aquifer interaction has been the subject of much research for cases of good hydraulic connection (continuous saturated zone) between a river and an aquifer. Under these conditions, floods do not represent a very large net input to the aquifer because most of the water that enters the aquifer during the flood returns to the river when its stage recedes. The situation is different in disconnected stream-aquifer systems, where the streambed lies above the water level in the aquifer, thus preventing return flow from the aquifer. Under these conditions, floods may represent large, but hard to quantify, water inputs. Here, we present a methodology to estimate recharge from floods for disconnected stream-aquifer systems. Recharge is estimated as the product of a flood time function (dependent on the streamflow) and an unknown factor, which is obtained from calibrating a ground water flow model to aquifer heads. The approach can also benefit from concentration data, which can be very informative when river water concentrations vary over time. This methodology is applied to a field situation where recharge from river flooding is found to amount to nearly 15 million m(3)/year on the average, which represents 40% of the total aquifer inputs. Recharge from flooding helps explain major head recoveries, suggesting that basin water management programs should allow some floods to occur. 相似文献
955.
A literature review on trace metals and organic compounds of anthropogenic origin in the Wider Caribbean Region 总被引:2,自引:2,他引:0
About 30 studies from the published literature were reviewed to determine the pollution status regarding heavy metals and organic compounds of the Wider Caribbean Region (WCR). The literature revealed that most studies were performed in the South and Central American Caribbean Region with sparse reports on the small island states. Collectively, the most frequently analyzed heavy metals were Pb, Cu, Zn, Fe, Cd, Ni, Mn and Cr while DDT and its metabolites were the most frequently reported organic pollutants. The samples which were analyzed vary in terms of sampling schemes, parameters and analytical techniques, as well as differences in data reporting presentation (i.e. dry weight versus wet weight, sediment fraction analyzed, or % lipids). These differences make meaningful comparisons of the available data very difficult. Furthermore, there is limited data available for most of these contaminants from the majority of nations in the WCR. Therefore, any attempt to create a regional scale assessment from contaminants data available in the open literature is limited by the scarcity of available information. 相似文献
956.
Neuroendocrine disruption in Mya arenaria clams during gametogenesis at sites under pollution stress 总被引:1,自引:0,他引:1
This study examined the neuroendocrine status of clams on intertidal mud flats in the St. Lawrence Estuary and Saguenay Fjord areas during late gametogenesis. The impact of pollution was determined by a test battery of early stress markers (metallothioneins, heme levels, glutathione S-transferase activity), tissue damage (lipid peroxidation and DNA damage) and morphologic characteristics (age, soft-tissue weight ratio and growth index). Neuroendocrinal status was examined by tracking serotonin and dopamine metabolism, monoamine adenylate cyclase activity in synaptosomes, monoamine oxidase and arachidonate cyclooxygenase activities in relation to gametogenetic activity: pyrimidine synthesis, (aspartate transcarbamoylase activity or ATC), vitellogenin-like proteins and gonado-somatic index. The results show that clam soft tissue weights were reduced at sites close to harbours and higher at sites near domestic wastewater outfalls. The age-to-length ratio of clams was generally higher at impacted sites, suggesting reduced growth. The biomarkers of stress or damage confirmed that oxidative stress, DNA damage, metallothioneins and glutathione S-transferase activity were significantly increased at varying degrees, at the polluted sites. Vitellogenin-like proteins and gametogenetic activity were significantly increased at sites influenced by domestic wastewaters. Furthermore, the clams were still in active gametogenesis and not ready for spawning, as indicated by the concordance of the serotonin/dopamine ratio with vitellogenin-like proteins and pyrimidine synthesis. However, gonadal cyclooxygenase activity was increased at polluted sites and significantly correlated with most of the stress biomarkers, suggesting that the clams were in a state of inflammation rather than at the spawning stage. Finally, a multivariate analysis revealed that the sites were readily discriminated with high efficiency (>71%) and that both neuroendocrine physiological markers and stress responses were identified as the major components, thus explaining the global physiological response of the clams. We conclude that the effects of pollution compromise the clams' health status and that the initiation of gametogenesis in environments contaminated by municipal wastewaters or harbours contributes to the toxic effects of pollution. 相似文献
957.
H. Lammer A. Hanslmeier J. Schneider I. K. Stateva M. Barthelemy A. Belu D. Bisikalo M. Bonavita V. Eybl V. Coudé du Foresto M. Fridlund R. Dvorak S. Eggl J. -M. Grießmeier M. Güdel E. Günther W. Hausleitner M. Holmström E. Kallio M. L. Khodachenko A. A. Konovalenko S. Krauss L. V. Ksanfomality Yu. N. Kulikov K. Kyslyakova M. Leitzinger R. Liseau E. Lohinger P. Odert E. Palle A. Reiners I. Ribas H. O. Rucker N. Sarda J. Seckbach V. I. Shematovich A. Sozzetti A. Tavrov M. Xiang-Grüß 《Solar System Research》2010,44(4):290-310
After the discovery of more than 400 planets beyond our Solar System, the characterization of exoplanets as well as their host stars can be considered as one of the fastest growing fields in space science during the past decade. The characterization of exoplanets can only be carried out in a well coordinated interdisciplinary way which connects planetary science, solar/stellar physics and astrophysics. We present a status report on the characterization of exoplanets and their host stars by reviewing the relevant space- and ground-based projects. One finds that the previous strategy changed from space mission concepts which were designed to search, find and characterize Earth-like rocky exoplanets to: A statistical study of planetary objects in order to get information about their abundance, an identification of potential target and finally its analysis. Spectral analysis of exoplanets is mandatory, particularly to identify bio-signatures on Earth-like planets. Direct characterization of exoplanets should be done by spectroscopy, both in the visible and in the infrared spectral range. The way leading to the direct detection and characterization of exoplanets is then paved by several questions, either concerning the pre-required science or the associated observational strategy. 相似文献
958.
Paula Chainho Gilda Silva Michael F. Lane José L. Costa Tadeu Pereira Carla Azeda Pedro R. Almeida Inês Metelo Maria J. Costa 《Estuaries and Coasts》2010,33(6):1314-1326
Long-term monitoring studies are needed to understand changes in ecosystem status when restoration measures are implemented.
A long-term data series (1996–2007) of the Tagus estuary (Portugal) intertidal and subtidal benthic communities was collected
in a degraded area where mitigation measures were implemented. Multivariate analysis was used to analyze spatial and temporal
patterns in benthic community composition and trends in five benthic community metrics (i.e., taxonomic richness, density,
biomass, Shannon–Wiener diversity and the AMBI index) were also examined. The results revealed a clear separation between
intertidal and subtidal assemblages, although they had 50% of taxa in common, including the most abundant. Significant positive
trends were found for all metrics showing that both intertidal and subtidal communities responded to the restoration measures
implemented. Nevertheless, biotic indices need some adaptation before being universally applied to intertidal and subtidal
habitats. 相似文献
959.
Rémy Roca Jean-Claude Bergès Hélène Brogniez Michel Capderou Philippe Chambon Olivier Chomette Sophie Cloché Thomas Fiolleau Isabelle Jobard Julien Lémond Mohamed Ly Laurence Picon Patrick Raberanto André Szantai Michel Viollier 《Comptes Rendus Geoscience》2010,342(4-5):390-402
The water and energy cycles are major elements of the Earth climate. These cycles are especially active in the intertropical belt where satellites provide the most suitable observational platform. The history of Earth observations of the water cycle and of the radiation budget viewed from space reveals that the fundamental questions from the early times are still relevant for today's research. The last 2 decades have seen a number of milestones regarding the documentation of rainfall, mesoscale convective systems (MCS), water vapour and radiation at the top of the atmosphere (TOA). Beyond dedicated missions that provided enhanced characterizations of some elements of the atmospheric water cycle and field campaigns that allowed the gathering of validation data, the advent of the long record of meteorological satellites lead to new questioning on the homogenisation of the data time series, etc. The use of this record to document the tropical climate brought new results of the distribution of humidity and reinforced the understanding of some robust features of the African monsoon. Challenges for the immediate future concerns the deepening of the understanding of the role of cloud systems in the monsoon circulation, the downscaling of the documentation of the water and energy cycle at the scale of these cloud systems, the research of better adequation between the users and the satellite estimate of rainfall and finally a much needed methodological effort to build exploitable time series for the estimation of climatic trends in the water and energy cycle in the Tropics. The required observations to address these challenges are rapidly presented with emphasis on the upcoming Megha-Tropiques (MT) mission. 相似文献
960.