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351.
Susan Owens 《Global Environmental Change》2010,20(3):394-401
This paper is concerned with environmental governance and policy formation in the area of climate change. Specifically, it examines a decision by the UK Government in 2003 to adopt a demanding, long-term CO2 emissions reduction target, following the advice of one of its longest standing environmental advisory bodies, the Royal Commission on Environmental Pollution. It explores the origins of the Commission's recommendation and the reasons for its relatively rapid uptake in public policy. It argues that in both cases, a complex mix of structural and contingent, cognitive and non-cognitive factors can be identified, operating at different levels of governance. Finally, the paper reflects on what we might learn from this particular case about policy processes and the role of knowledge and expert advice within them. 相似文献
352.
Melina Ey Jai Allison Susan Caves Eliza Crosbie Ainsley Hughes 《The Australian geographer》2020,51(3):283-305
ABSTRACT In neoliberalising universities, collegial and collective practices such as reading groups are often positioned by students, staff and managers as less important than meeting individual KPIs (such as producing research publications, seeking research grants, or meeting the increasing demands of producing quality teaching outcomes.) However, reading groups can be vital for cultivating caring collectives and spaces of collegiality. In this paper we use assemblage thinking to explore 25 years of a Geography reading group at the University of Newcastle. The paper addresses two questions: what does reading together do and make possible; and how might we think about the labours of reading together as a way of building caring collectives. The paper draws on reflections from 24 past and present members of reading group to explore how these kinds of academic practices nourish our working lives. 相似文献
353.
This editorial introduction to the themed issue is divided into four parts. We begin with outlining five reasons for more sustained attention to ageing and old age in human geography and go onto discuss two major challenges for geographical inquiry into ageing and later life. One of these is examining embodiment in ways that keep both its social/cultural aspects and its biological/physiological dimensions in sharp focus; the other concerns the challenge of considering time, or rather spatiotemporality, in all its facets. With regard to the latter we argue that the life-course concept can be helpful in this regard, especially if attention is paid to transitions as well as to slow, difficult-to-identify forms of change and if life-courses are understood in terms of folds. Thinking in these terms opens up a perspective according to which ageing and space can be analysed as entwined becomings. We conclude by positioning the contributions in this issue vis-à-vis the perspective developed in this piece. 相似文献
354.
Edward J. Phlips Susan Badylak Jane Hart Daniel Haunert Jean Lockwood Kathyrn O’Donnell Detong Sun Paula Viveros Mete Yilmaz 《Estuaries and Coasts》2012,35(1):335-352
The St. Lucie Estuary, located on the southeast coast of Florida, provides an example of a subtropical ecosystem where seasonal
changes in temperature are modest, but summer storms alter rainfall regimes and external inputs to the estuary from the watershed
and Atlantic Ocean. The focus of this study was the response of the phytoplankton community to spatial and temporal shifts
in salinity, nutrient concentration, watershed discharges, and water residence times, within the context of temporal patterns
in rainfall. From a temporal perspective, both drought and flood conditions negatively impacted phytoplankton biomass potential.
Prolonged drought periods were associated with reduced nutrient loads and phytoplankton inputs from the watershed and increased
influence of water exchange with the Atlantic Ocean, all of which restrict biomass potential. Conversely, under flood conditions,
nutrient loads were elevated, but high freshwater flushing rates in the estuary diminished water residence times and increase
salinity variation, thereby restricting the buildup of phytoplankton biomass. An exception to the latter pattern was a large
incursion of a cyanobacteria bloom from Lake Okeechobee via the St. Lucie Canal observed in the summer of 2005. From a spatial
perspective, regional differences in water residence times, sources of watershed inputs, and the proximity to the Atlantic
Ocean influenced the composition and biomass of the phytoplankton community. Long water residence times in the North Fork
region of the St. Lucie Estuary provided an environment conducive to the development of blooms of autochthonous origin. Conversely,
shorter residence times in the mid-estuary limit autochthonous increases in biomass, but allochthonous sources of biomass
can result in bloom concentrations of phytoplankton. 相似文献
355.
The eastern Alaska Beaufort Sea coast is characterized by numerous shallow (2–5 m) estuarine lagoons, fed by streams and small
rivers that drain northward from the Brooks Range through the arctic coastal plain, and bounded seaward by barrier islands
and shoals. Millions of birds from six continents nest and forage during the summer period in this region using the river
deltas, lagoons, and shoreline along with several species of anadromous and marine fish. We examined biogeochemical processes
linking the benthic community to the overall food web structure of these poorly studied but pristine estuaries, which are
largely covered by 1.8 m of ice for 10 months annually. In summer, these lagoons are relatively warm with brackish salinities
(5–10°C, S = 10–25) compared to more open coastal waters (0–5°C, S > 27). The stable isotopic composition of organic materials in sediments (i.e., benthic particulate organic matter) and water
column suspended particulate organic matter from both streams and lagoons are largely indistinguishable and reflect strong
terrestrial contributions, based upon δ13C and δ15N values (−25.6‰ to −27.4‰ and 1.4‰ to 3.3‰, respectively). By comparison, shifts toward more heavy isotope-enriched organic
materials reflecting marine influence are observed on the adjacent coastal shelf (−24.8‰ to −25.4‰ and 3.4‰ to 5.3‰, respectively).
The isotopic composition of lagoon fauna is consistent with a food web dominated by omnivorous detritovores strongly dependent
on microbial processing of terrestrial sources of carbon. Biomagnification of 15N in benthic organisms indicate that the benthic food web in lagoons support up to four trophic levels, with carnivorous gastropod
predators and benthic fishes (δ15N values up to 14.4‰) at the apex. 相似文献
356.
Troy A. Dexter Darrell S. Kaufman Richard A. Krause Jr. Susan L. Barbour Wood Marcello G. Simões John Warren Huntley Yurena Yanes Christopher S. Romanek Michał Kowalewski 《Quaternary Research》2014
To evaluate the potential of using surficial shell accumulations for paleoenvironmental studies, an extensive time series of individually dated specimens of the marine infaunal bivalve mollusk Semele casali was assembled using amino acid racemization (AAR) ratios (n = 270) calibrated against radiocarbon ages (n = 32). The shells were collected from surface sediments at multiple sites across a sediment-starved shelf in the shallow sub-tropical São Paulo Bight (São Paulo State, Brazil). The resulting 14C-calibrated AAR time series, one of the largest AAR datasets compiled to date, ranges from modern to 10,307 cal yr BP, is right skewed, and represents a remarkably complete time series: the completeness of the Holocene record is 66% at 250-yr binning resolution and 81% at 500-yr binning resolution. Extensive time-averaging is observed for all sites across the sampled bathymetric range indicating long water depth-invariant survival of carbonate shells at the sediment surface with low net sedimentation rates. Benthic organisms collected from active depositional surfaces can provide multi-millennial time series of biomineral records and serve as a source of geochemical proxy data for reconstructing environmental and climatic trends throughout the Holocene at centennial resolution. Surface sediments can contain time-rich shell accumulations that record the entire Holocene, not just the present. 相似文献
357.
正On 22nd April 2014,with the approach of the 45th World Earth Day,the Chinese Ministry of Land and Resources announced the status of China’s land resources in 2013,putting forward the implementation of strict farmland protection measures to ensure the 1.8 billion acres of arable land.This laid a solid foundation for achieving a"ten even increase"of 相似文献
358.
正The 12th International Conference on Salt Lake Research,which is organized jointly by International Society of Salt Lake and The Institute of Mineral Resources,Chinese Academy of Geological Sciences,will be held on July 14–18,2014 in Langfang,Hebei Province,China.The conference themes focus on future and global salt lake sustainable research and development and will bring together international specialists in limnology,sedimentology,geology,geochemistry,biology, 相似文献
359.
China, as many other parts of the world, has a serious shortage of water resources. In China, there is a total amount of 2.8×10^12 m3 of freshwater, but that is only 2000 m3 per capita, which is about one quarter of the world average. Thereforc, seawater desalination engineering is of great significance to the nation. 相似文献
360.
On l lth September 2013, the Inner Mongolia Mineral Resources and Reserves Evaluation Center estimated that the world's third-largest molybdenum deposit had been found in the Caosiyao area of Xinghe County, Inner Mongolia, NE China. The find has 130235.60×10^4 t of (122b)+(333) molybdenum ores, a metal amount of 1327649.27 t, with Mo grade of 0.102-a super-large one. 相似文献