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61.
A comprehensive review of climate adaptation in the United States: more than before, but less than needed 总被引:2,自引:0,他引:2
Rosina Bierbaum Joel B. Smith Arthur Lee Maria Blair Lynne Carter F. Stuart Chapin III Paul Fleming Susan Ruffo Missy Stults Shannon McNeeley Emily Wasley Laura Verduzco 《Mitigation and Adaptation Strategies for Global Change》2013,18(3):361-406
We reviewed existing and planned adaptation activities of federal, tribal, state, and local governments and the private sector in the United States (U.S.) to understand what types of adaptation activities are underway across different sectors and scales throughout the country. Primary sources of review included material officially submitted for consideration in the upcoming 2013 U.S. National Climate Assessment and supplemental peer-reviewed and grey literature. Although substantial adaptation planning is occurring in various sectors, levels of government, and the private sector, few measures have been implemented and even fewer have been evaluated. Most adaptation actions to date appear to be incremental changes, not the transformational changes that may be needed in certain cases to adapt to significant changes in climate. While there appear to be no one-size-fits-all adaptations, there are similarities in approaches across scales and sectors, including mainstreaming climate considerations into existing policies and plans, and pursuing no- and low-regrets strategies. Despite the positive momentum in recent years, barriers to implementation still impede action in all sectors and across scales. The most significant barriers include lack of funding, policy and institutional constraints, and difficulty in anticipating climate change given the current state of information on change. However, the practice of adaptation can advance through learning by doing, stakeholder engagements (including “listening sessions”), and sharing of best practices. Efforts to advance adaptation across the U.S. and globally will necessitate the reduction or elimination of barriers, the enhancement of information and best practice sharing mechanisms, and the creation of comprehensive adaptation evaluation metrics. 相似文献
62.
Ellen M. Douglas Paul H. Kirshen Michael Paolisso Chris Watson Jack Wiggin Ashley Enrici Matthias Ruth 《Mitigation and Adaptation Strategies for Global Change》2012,17(5):537-562
We explored the possible future impacts of increased coastal flooding due to sea level rise and the potential adaptation responses
of two urban, environmental justice communities in the metropolitan Boston area of Massachusetts. East Boston is predominantly
a residential area with some industrial and commercial activities, particularly along the coastal fringe. Everett, a city
to the north of Boston, has a diversified industrial and commercial base. While these two communities have similar socioeconomic
characteristics, they differ substantially in the extent to which residents would be impacted by increased coastal flooding.
In East Boston, a large portion of residents would be flooded, while in Everett, it is the commercial/industrial districts
that are primarily vulnerable. Through a series of workshops with residents in each community, we found that the target populations
do not have an adaptation perspective or knowledge of any resources that could assist them in this challenge. Furthermore,
they do not feel included in the planning processes within their communities. However, a common incentive for both communities
was an intense commitment to their communities and an eagerness to learn more and become actively engaged in decisions regarding
climate change adaptation. The lessons that can be applied to other studies include 1) images are powerful tools in communicating
concepts, 2) understanding existing cultural knowledge and values in adaptation planning is essential to the planning process
and 3) engaging local residents at the beginning of the process can create important educational opportunities and develop
trust and consensus that is necessary for moving from concept to implementation. 相似文献
63.
The fate of Norse farming settlements in southwest Greenland has often been seen as one of the great mysteries of North Atlantic colonization and expansion. Preservation of organic remains in the permafrost of the area of the Western Settlement, inland from the modern capital Nuuk, allowed very detailed study of the phases of occupation. Samples were taken from house floors and middens during the process of archaeological excavations and from insect remains were abstracted and identified in the laboratory. In this study, we present a new paleoecological approach principally examining the fossil fly faunas from house floors. The results of our study provide contrasting detailed pictures of the demise of two neighboring farms, Gården under Sandet and Nipaatsoq, one where abandonment appears as part of a normal process of site selection and desertion, and the other where the end was more traumatic. The level of detail, which was obtained by analysis of the dipterous (true fly) remains, exceeds all previous work and provides insights otherwise unobtainable. 相似文献
64.
In this study, landmark-based methods of geometric morphometrics are used for investigating the main aspects of cranial shape transformation in the evolution of the giant panda, Ailuropoda melanoleuca. Specifically, we explore if the highly derived cranial adaptations for bamboo feeding of the living panda were developed early in the panda's lineage. Results obtained show that the overall cranial morphologies of the oldest known panda, the "pygmy" Ailuropoda microta, and the late Pleistocene Ailuropoda baconi are both very similar to that of their closest living relative, A. melanoleuca, which agrees with a previous proposal based on qualitative criteria. However, we also describe several differences between the crania of A. microta, A. baconi, and A. melanoleuca, including the development of the postorbital process, the orientation of the occipital region, and the expansion of the braincase. As a result, the cranial morphology of A. microta shows a less specialized morphology toward a fibrous and durophagous diet compared to the giant panda. These results are confirmed by a comparative analysis of the dimensions of the upper teeth in bears, which has revealed differences in relative tooth size between A. microta and A. melanoleuca, most probably as a result of mosaic evolution. Therefore, we conclude that cranial shape did not remain essentially uniform in the Ailuropoda lineage, as previously thought, but underwent a number of changes during more than 2?Myr. 相似文献
65.
Despite having a strong influence on development policies, theories of sustainability have not paid much attention to the capability approach (CA) thus far. Against this backdrop, the present paper argues for the CA’s usefulness of sustainability. In order to avoid just an additional contribution to the already confusing theoretical situation as well as to rely our exploration of the CA’s aptness for a conception of sustainability on a transparent and comparable basis, we will first identify six adequacy conditions for concepts of sustainability. We will then work out a categorial framework for conceptions of sustainability. Finally we will demonstrate how the CA is a promising candidate for filling in the demands of this framework and what further research will be needed. 相似文献
66.
Dietary PBDE intake: a market-basket study in Belgium 总被引:1,自引:0,他引:1
A food market-basket, representative for the general Belgian population, containing various meat, fish and dairy food products, was assembled and analysed for its polybrominated diphenyl ether (PBDE) content. Additionally, fast food samples were also investigated. Based on the measured PBDE levels, an average daily dietary intake estimate of PBDEs was calculated. Of all foods analysed, fish had the highest average sum of PBDE levels (BDEs 28, 47, 99, 100, 153, 154, and 183; 460 pg/g ww), followed by dairy products and eggs (260 pg/g ww), fast food (86 pg/g ww) and meat products (70 pg/g ww). One fresh salmon filet had the highest total concentration of PBDEs (2360 pg/g ww), whereas levels in steak and chicken breast were the lowest of all foods analysed. BDE 209 was never found above LOQ in any food. PBDE intake calculations were based on the average daily food consumption in Belgium and were estimated between 23 and 48 ng/day of total PBDEs (lower and upper bound). This value is in accordance with what was previously reported for diets from geographical distinct areas, such as Canada, Finland, Spain, Sweden and the UK. Although it is only a minor constituent of the Belgian diet, fish is the major contributor to the total daily PBDE-intake (around 40%) due to the high PBDE levels in this type of food. Although low contaminated, meat products account for around 30% of the total dietary intake of PBDEs. Dairy products and eggs contribute to a lesser degree (less than 30%). 相似文献
67.
Julien Benoit Sandra C. Jasinoski Vincent Fernandez Fernando Abdala 《Die Naturwissenschaften》2017,104(7-8):66
The basal non-mammaliaform cynodonts from the late Permian (Lopingian) and Early Triassic are a major source of information for the understanding of the evolutionary origin of mammals. Detailed knowledge of their anatomy is critical for understanding the phylogenetic transition toward mammalness and the paleobiological reconstruction of mammalian precursors. Using micro-computed tomography (μCT), we describe the internal morphology of the interorbital region that includes the rarely fossilized orbitosphenoid elements in four basal cynodonts. These paired bones, which are positioned relatively dorsally in the skull, contribute to the wall of the anterior part of the braincase and form the floor for the olfactory lobes. Unlike procynosuchids and the more basal therapsids in which the orbitosphenoids are well developed, dense, and bear a ventral keel, the basal epicynodonts Cynosaurus, Galesaurus, and Thrinaxodon display cancellous, reduced, and loosely articulated orbitosphenoids, a condition shared with many eucynodonts. The hemi-cylindrical orbitosphenoid from which the mammalian condition is derived re-evolved convergently in traversodontid and some probainognathian cynodonts. 相似文献
68.
Annekatrin Wagner Stephan Hülsmann Lothar Paul Rüdiger J. Paul Thomas Petzoldt René Sachse Thomas Schiller Bettina Zeis Jürgen Benndorf Thomas U. Berendonk 《Marine Biology》2012,159(11):2543-2559
To predict the coherence in local responses to large-scale climatic forcing among aquatic systems, we developed a generalized approach to compare long-term data of dimictic water bodies based on phenomenologically defined hydrographic events. These climate-sensitive phases (inverse stratification, spring overturn, early thermal stratification, summer stagnation) were classified in a dual code (cold/warm) based on threshold temperatures. Accounting for a latitudinal gradient in seasonal timing of phases derived from gradients in cumulative irradiation (2.2?days per degree latitude), we found a high spatial and temporal coherence in warm–cold patterns for six lakes (84?%) and the Baltic Sea (78?%), even when using the same thresholds for all sites. Similarity to CW-codes for the North Sea still was up to 72?%. The approach allows prediction of phase-specific warming trends and resulting instantaneous or time-delayed ecological responses. Exemplarily, we show that warming during early thermal stratification controls food-web-mediated effects on key species during summer. 相似文献
69.
70.
The cardinalfish Siphamia versicolor (Perciformes: Apogonidae) forms a bioluminescent symbiosis with the marine luminous bacterium Photobacterium mandapamensis, harboring the bacteria in a ventral, disc-shaped light organ and using the bacterial light apparently for counterillumination
and attracting prey. Little definitive information has been available on the developmental and microbiological events surrounding
the initiation of symbiosis, a critical stage in the life history of the fish, in S. versicolor or any of the many other species of bacterially luminous fish. To identify the stage at which light organ formation begins,
to determine the origin of cells forming the light organ, and to characterize its bacterial colonization status during development,
early developmental stages of S. versicolor obtained and reared from wild-caught mouth-brooding males were examined with histological and microbiological methods. A
light organ primordium was not evident in embryos, post-embryos, or pre-release larvae, whereas the light organ began to form
within 1 day of release of full-term pre-flexion larvae from the mouths of male fish. Analysis of post-release larvae revealed
that the light organ arises from a proliferation and differentiation of intestinal epithelial cells, and that it quickly develops
structural complexity, including the formation of chambers and gaps contiguous with the intestinal epithelium. However, the
nascent light organ remained uncolonized by the symbiotic bacteria through several days of post-release development, even
in the presence of high numbers of the symbiotic bacteria. These results demonstrate that the inception of light organ formation
in S. versicolor occurs independently of its symbiotic bacteria and that receptivity to bacterial colonization apparently requires substantial
post-release development of the light organ. Larvae therefore most likely acquire their symbiotic bacteria from seawater,
during or shortly after the transition from the pre-flexion to the flexion developmental stage. 相似文献