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251.
The concept of community identity has often been employed to explain ways in which communities respond to agents that impact community well-being. Using a case study of the Florida cattlemen community, we examine how cattlemen understand and perceive regulatory efforts to recover the Florida panther on private ranch lands. The data comes from participants in the Florida cattlemen community, and was collected through in-depth interviews (n = 13), group interviews (n = 32), and written comments associated with a survey about panther conservation (n = 78). Our findings indicate that some cattlemen in Florida have a strong sense of community identity. Perceptions of government actions and variation in economic risks are critical factors in understanding how this community responds to federal interventions. Our findings suggest that the concept of community identity can be used to explain the responses of agricultural landowners to governmental policies that are perceived as a threat to collective identity.  相似文献   
252.
Health geography in Aotearoa New Zealand (NZ) has had a major impact on international sub‐disciplinary debates. It is timely to celebrate our domestic health geography achievements and alert ourselves to the challenges ahead. This reflection article provides a brief overview of Aotearoa NZ's maturing health geography community and includes the reflections of a panel discussion held during the bi‐annual NZ Geographical Society conference in 2016. We argue that the eclectism of health geography in NZ and beyond is both the sub‐discipline's major strength and challenge.  相似文献   
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254.
Achieving the international 2 °C limit climate policy requires stringent reductions in GHG emissions by mid-century, with some countries simultaneously facing development-related challenges. South Africa is a middle-income developing country with high rates of unemployment and high levels of poverty, as well as an emissions-intensive economy. South Africa takes into account an assessment of what a fair contribution to reducing global emissions might be, and is committed to a ‘peak, plateau and decline' emissions trajectory with absolute emissions specified for 2025 and 2030, while noting the need to address development imperatives. This work utilizes an economy-wide computable general equilibrium model (e-SAGE) linked to an energy-system optimization model (TIMES) to explore improving development metrics within a 14 GtCO2e cumulative energy sector carbon constraint through to 2050 for South Africa. The electricity sector decarbonizes by retiring coal-fired power plants or replacing with concentrated solar power, solar photovoltaics and wind generation. Industry and tertiary-sector growth remains strong throughout the time period, with reduced energy intensity via fuel-switching and efficiency improvements. From 2010 to 2050, the model results in the unemployment rate decreasing from 25% to 12%, and the percentage of people living below the poverty line decreasing from 49% to 18%. Total energy GHG emissions were reduced by 39% and per capita emissions decreased by 62%.

Policy relevance

Lower poverty and inequality are goals that cannot be subordinated to lower GHG emissions. Policy documents in South Africa outline objectives such as reducing poverty and inequality with a key focus on education and employment. In its climate policy and Intended Nationally Determined Contribution (INDC), South Africa is committed to a peak, plateau and decline GHG emissions trajectory. As in many developing countries, these policy goals require major transformations in the energy system while simultaneously increasing affordable access to safe and convenient energy services for those living in energy poverty. The modelled scenario in this work focuses on employment and poverty reduction under a carbon constraint, a novel combination with results that can provide information for a holistic climate and development policy framework. This study has focused on the long term, which is important in generating clear policy signals for the necessary large-scale investments.  相似文献   
255.
Based on the surface drifters that moved out from the Sea of Okhotsk to the Pacific, the surface velocity fields of mean, eddy, and tidal components in the Oyashio region are examined for the period September 1999 to August 2000. Along the southern Kuril Island Chain, the Oyashio Current, having a width of ∼100 km, exists with velocities of 0.2–0.4 m s−1. From 40°N to 43°N, the Subarctic Current flows east- or northeastward with velocities of 0.1–0.3 m s−1, accompanied by a meandering Oyashio or Subarctic front. Between the Oyashio and Subarctic current regions, an eddy-dominant region exists with both cyclonic and anticyclonic eddies. The existence of an eastward flow just south of Bussol' Strait is suggested. The 2000 anticyclonic warmcore ring located south of Hokkaido was found to have a nearly symmetric velocity structure with a maximum velocity of ∼0.7 m s−1 at 70 km from the eddy center. Diurnal tidal currents with a clockwise tidal ellipse are amplified over the shelf and slope off Urup and Iturup Islands, suggesting the presence of diurnal shelf waves. From Lagrangian statistics, the single-particle diffusivity is estimated to be ∼10 × 107 cm2s−1.  相似文献   
256.
This report is the first seasonal study of anthropogenic pollutant biodegradation rates in Antarctic coastal waters. The capacity of surface waters from Rothera Research Station, Adelaide Island, Antarctica, to biodegrade the anionic surfactant sodium dodecyl sulphate (SDS) was quantified in biodegradation tests from April 1988 to January 1999. Large temporal differences in the persistence of SDS were observed. In mid-winter (July), the SDS-biodegradation half life was twice that measured in mid-summer (January), despite small temperature differences (up to 2.45 degrees C). Comparisons between water from a pristine site and a site receiving grey-waste water from the station showed that some acclimation to SDS was occurring in the contaminated water. This resulted in SDS half lives up to to approximately 80 h shorter in the polluted water compared with the pristine site in the summer months when a large population of SDS-degrading bacteria had developed. Biodegradation half lives in Antarctic coastal waters (160-460 h) were generally far higher than those observed in temperate waters.  相似文献   
257.
Measurements are presented of the water particle kinematics of focused wave groups generated in the U.K. Coastal Research Facility. Single and repeated wave groups are considered at normal and 20° incidence to a 1:20 plane beach. The single focused wave groups model extreme transient events without the complication of reflections during the data acquisition process. A symmetry-based separation of harmonics method is used to interpret the water particle kinematics at the point of focus. Although the largest component is linear, there are also considerable second order kinematics terms (both low frequency and high frequency). Away from the free surface, the 2nd order difference contribution to the kinematics is a return current opposed to the direction of wave advance. For repeated wave groups, the measured kinematics confirms the presence of a low frequency free wave, followed by higher frequency waves of the main group and trailing higher order harmonic waves. In the breaker and surf zones, there is also evidence of the saw-tooth behaviour of broken waves, followed by scatter due to breaker-induced turbulence. Pulsatile wave breaking of repeated wave groups at oblique incidence is found to drive a longshore current.  相似文献   
258.
In static toxicity experiments, tolerance to soluble Cu of the bivalve, Macoma balthica, and the copepod, Acartia clausi, varied substantially among populations sampled within San Francisco Bay. Intraspecific tolerance differed ten-fold or more for both species over relatively small distances, suggesting geographical isolation of populations is not a prerequisite for the development of intraspecific differences in tolerance by aquatic organisms.  相似文献   
259.
260.
A sequential extraction procedure, using acid digestion in a CEM MDS-81D® microwave system, is reported for the investigation of trace and minor element associations in coal in (1) mineral phases other than pyrite, (2) pyrite and (3) the organic matrix. The concentrations of sulphate, pyrite and organic sulphur can also be determined by this method. The extract solutions from each stage are rapidly analysed by ICP-AES. The association of major, minor and trace elements with mineral and organic phases is suggested for a suite of certified reference coal samples. In stage 1, a significant percentage of the total Ba, Co, Cr, Cu, Mn, Ni, Pb and Sr was extracted suggesting an association with silicate, carbonate, sulphate and phosphate minerals for these elements. In stage 2, a proportion of the Cu, Mn, Ni, Pb and Zn was dissolved implying the occurrence of these elements in pyrite. An association with the organic matrix is suggested for Cr and also for Ba and Sr in lower rank coals.  相似文献   
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