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Carola Betzold Thomas Bernauer Vally Koubi 《Environmental Communication: A Journal of Nature and Culture》2016,10(5):575-592
Press conferences are an important element of a government's communication strategy at climate change summits. From a theoretical perspective, press conferences should serve two main functions: exerting pressure in negotiations and informing the public. These functions correspond to two logics of action: a logic of consequence where governments use press conferences as negotiation tools and a logic of appropriateness where governments organize press conferences to increase transparency. Based on new data from the United Nations Framework Convention on Climate Change archives, we find limited support for these two logics of action. Neither democracies, which, we argue, are more likely to follow a logic of appropriateness, nor vulnerable countries, which are more likely to follow a logic of consequence, organize systematically more press conferences. Other factors, such as capacity and a government's function in the negotiation structure, seem to play a more important role. 相似文献
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To determine nutritional and social influences on life history traits and mating behavior in female langur monkeys, new long-term data for a feral population living in multi-male groups under poor nutritional conditions are presented and compared with published long-term data for the same species living in one-male groups under excellent nutritional conditions. Under poor nutritional conditions, conceptions were confined to 5 months per year, coinciding with the period of the highest mating activity. Age at first parturition, gestation periods, lactation periods, and interbirth intervals were all significantly increased resulting in a more than 50% reduced reproductive rate under poor conditions. The pattern of sexual behavior during gestation was influenced by neither nutritional nor social conditions but the frequency was higher in multi-male groups. Furthermore, estrus length was significantly increased in multi-male groups where females tended to mate with as many resident males as available. Both phenomena, together with a high percentage of sexual behavior occurring outside the mid-cycle estrus, are interpreted in the light of paternity confusion in multi-male groups in a species where infanticide by males is regularly observed. The extreme variation in life history traits and mating patterns disclosed here in one species suggests that future cross-species comparisons should strictly select datasets based on local ecological and social conditions. 相似文献
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Bryan CE Davis WC McFee WE Neumann CA Schulte J Bossart GD Christopher SJ 《Chemosphere》2012,89(5):556-562
More than half of pygmy sperm whales (Kogia breviceps) that strand exhibit signs of cardiomyopathy (CMP). Many factors may contribute to the development of idiopathic CMP in K. breviceps, including genetics, infectious agents, contaminants, biotoxins, and dietary intake (e.g. selenium, mercury, and pro-oxidants). This study assessed trace elements in K. breviceps at various stages of CMP progression using fresh frozen liver and heart samples collected from individuals that stranded along US Atlantic and Gulf coasts between 1993 and 2007. Standard addition calibration and collision cell inductively coupled plasma mass spectrometry (ICP-MS) were employed for total Se analysis and pyrolysis atomic absorption (AA) was utilized for total Hg analysis to examine if the Se/Hg detoxification pathway inhibits the bioavailability of Se. Double spike speciated isotope dilution gas chromatography ICP-MS was utilized to measure methyl Hg and inorganic Hg. Immunoblot detection and colorimetric assays were used to assess protein oxidation status. Data collected on trace elements, selenoproteins, and oxidative status were evaluated in the context of animal life history and other complementary histological information to gain insight into the biochemical pathways contributing to the development of CMP in K. breviceps. Cardiomyopathy was only observed in adult pygmy sperm whales, predominantly in male animals. Both Hg:Se molar ratios and overall protein oxidation were greater in males than females and increased with progression of CMP. 相似文献
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Kim Yrjälä Anna-Kaisa Keskinen Carola Fortelius 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1680-1688
To reveal the degradation capacity of bacteria in PAH polluted soil and rhizosphere we combined bacterial extradiol ring-cleavage dioxygenase and 16S rRNA analysis in Betula pubescens rhizoremediation. Characterisation of the functional bacterial community by RFLP revealed novel environmental dioxygenases, and their putative hosts were studied by 16S rRNA amplification. Plant rhizosphere and PAH amendment effects were detected by the RFLP/T-RFLP analysis. Functional species richness increased in the birch rhizosphere and PAH amendment impacted the compositional diversity of the dioxygenases and the structural 16S rRNA community. A shift from an Acidobacteria and Verrucomicrobia dominated to an Alpha- and Betaproteobacteria dominated community structure was detected in polluted soil. Clone sequence analysis indicated catabolic significance of Burkholderia in PAH polluted soil. These results advance our understanding of rhizoremediation and unveil the extent of uncharacterized functional bacteria to benefit bioremediation by facilitating the development of the molecular tool box to monitor bacterial populations in biodegradation. 相似文献
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Dispersal and Use of Corridors by Birds in Wooded Patches on an Agricultural Landscape 总被引:11,自引:0,他引:11
Carola A. Haas 《Conservation biology》1995,9(4):845-854
Dispersal behavior has important effects on the persistence and recolonization of populations, but is one of the least understood traits of most organisms. Knowledge of patterns of fledgling, natal, and breeding dispersal of birds in a patchy environment will assist in decisions regarding reserve design and protection or construction of corridors. I present data on movement patterns of three migratory bird species, American Robin ( Turdus migratorius ), Brown Thrasher ( Toxostoma rufum ), and Loggerhead Shrike ( Lanius ludovicianus ). These birds are relatively common breeders in south-central North Dakota (U.S.) in riparian woodlands and in shelterbelts (woodlots planted as windbreaks in the open agricultural environment). Field assistants and I individually marked and monitored the movements of more than 500 adults breeding in a network of shelterbelts across an 8 × 11 km study area. Most movement occurred at relatively short distances within a shelterbelt. Movements by adults between shelterbelt sites, although rare, occurred significantly more frequently between sites connected by a wooded corridor than between unconnected sites. For robins, there were on average 2.5 dispersal events between each pair of connected sites, but only 0.17 dispersal events between each pair of unconnected sites (Mann-Whitney test, significant at p < 0.009). Because unconnected and connected sites were similar in average area (1.7 to 1.9 ha), distance to next wooded habitat, and tree-species composition, this result provides a test of the hypothesis that organisms disperse preferentially along connecting corridors. 相似文献
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Sebastian Busse Dominik Lutter Gerhard Heldmaier Martin Jastroch Carola W. Meyer 《Die Naturwissenschaften》2014,101(11):1003-1006
The grey short-tailed opossum, Monodelphis domestica, has been an established research animal for more than five decades, but relatively, little is known about its thermophysiology. Here we studied core body temperature (T b) and metabolic rate (MR) of female adult M. domestica housed in the laboratory at an ambient temperature (T a) of 26 °C. In expanding previous reports, the average recorded core T b of M. domestica was 34.3 °C. The T b of an individual M. domestica can drop below 30 °C (minimal T b: 28.6 °C) accompanied by a reduction in MR of up to 52 % even while having ad libitum access to food. These findings demonstrate for the first time the presence of spontaneous torpor in M. domestica. Metabolic suppression at relatively high T a and T b furthermore broadens our perspective on the use of torpor as a metabolic strategy not just restricted to cold climates. 相似文献
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Paolo Casale Marco Affronte Dino Scaravelli Bojan Lazar Carola Vallini Paolo Luschi 《Marine Biology》2012,159(7):1527-1535
Knowledge about migratory routes and highly frequented areas is a priority for sea turtle conservation, but the movement patterns of juveniles frequenting the Adriatic have not been investigated yet, although juveniles represent the bulk of populations. We tracked by satellite six juvenile and one adult female loggerhead from the north Adriatic. The results indicated that loggerhead juveniles (1) can either show a residential behaviour remaining in the Adriatic throughout the year or perform seasonal migrations to other areas, (2) can remain even in the coldest, northernmost area during winter, (3) can frequent relatively small foraging areas, (4) mostly frequent the eastern part of the Adriatic, and (5) follow preferred migratory routes along the western and eastern Adriatic coasts. The movements of the adult turtle also revealed (6) a behavioural polymorphism in Mediterranean adults, which included a lack of area fidelity and connection between distant neritic foraging grounds. 相似文献