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New Zealand's policy goal to preserve coastal natural character was first incorporated into planning legislation in 1973 and protected area legislation in 1977. An evaluation of 100 relevant Resource Management Act Court decisions determined the Courts' interpretations of this policy goal. The Courts have repeatedly found that natural character is of nature (not culture), including natural elements, patterns, and processes. There is a continuum of naturalness from pristine indigenous ecosystems to the urban environment. A 2014 Supreme Court decision has upheld the use of environmental bottom lines for natural character and the importance of protection as part of sustainable management.  相似文献   
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Sm‐Nd and Rb‐Sr isotopic data for Archaean gneisses from three localities within the eastern Yilgarn Block of Western Australia indicate that the gneisses define a precise Rb‐Sr whole rock isochron age of 2780 ± 60 Ma and an initial 87Sr/86Sr of 0.7007 ± 5. The Sm‐Nd isotopic data do not correspond to a single linear array, but form two coherent groups that are consistent with a c. 2800 Ma age of crust formation, with variable initial Nd. These results indicate that the gneiss protoliths existed as continental crust for a maximum period of only c. 100 Ma, and probably for a much shorter time, prior to the formation of the 2790 ±30 Ma greenstones.  相似文献   
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In an effort to investigate both large-scale (spatial) and short/long-term (temporal) distribution characteristics of atmospheric mercury, we have combined and analyzed the Hg concentration data sets collected continuously by four different scientific groups for the areas and periods covering (1) America (three sites near the Canadian Great Lakes (CGL): 1997–2000), (2) Asia (Seoul, Korea (SEL): 1997–2002), (3) Arctic (Alert, Canada (ALT): 1995–2001), and (4) Europe (Mace Head, Ireland (MH): 1996–2002). The mean concentrations of Hg data from those widely dispersed monitoring stations were computed to be (1) 1.58 ± 0.23, 1.69 ± 0.32, and 1.93 ± 0.44 (three sites in CGL), (2) 5.06 ± 2.46 ng m–3 (SEL), (3) 1.55 ± 0.41 (ALT), and (4) 1.76 ± 0.31 (MH). Intersite relationships were investigated among all different stations using the data groups divided into different temporal intervals. The analysis of diurnal variation patterns of Hg indicated differences in regional source/sink characteristics, with increasing amplitudes of variability toward areas under the strong influence of anthropogenic sources. When the analysis was made over different seasons, the patterns contrasted greatly between the Arctic and the other areas. It was found that the relative enhancement of Hg concentrations was dominant during winter/spring in most areas due to direct or indirect influences of anthropogenic emissions. However, the pattern for the Arctic area was distinguished pronouncedly from others with the spring minimum and summer maximum both of which reflect the potent effects of mercury depletion phenomenon (MDP). By contrast, no long-term trend, either being an increase or decrease, was evident from any of the stations during each respective study period. Although our initial attempts to examine the distribution characteristics of Hg analyzed by different scientific groups were successful, we feel that these efforts should be continued further to extend the compatibility of the global database of Hg.  相似文献   
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The wavelength of stationary water‐surface waves and their associated antidune bedforms are related to the mean velocity and depth of formative flow. In past published sand‐bed flume experiments, it was found that lens structures were preserved during antidune growth and change, and the dimension of the lenses was empirically related to antidune wavelength, and thus could be used to estimate flow velocity and depth. This study is the first to compare observations of formative flow conditions and resulting sedimentary structures in a natural setting, testing the previously published relationship at a field‐scale. Trains of stationary and upstream migrating water‐surface waves were prevalent during the flash flood in October 2012 in the Belham Valley, Montserrat, West Indies. Wave positions and wavelengths were assessed at 900 sec intervals through the daylight hours of the event within a monitored reach. The wave data indicate flow depths up to 1·3 m and velocity up to 3·6 m sec?1. Sedimentary structures formed by antidune growth and change were preserved in the event deposit. These structures include lenses of clast‐supported gravel and massive sand, with varying internal architecture. The lenses and associated low‐angle strata are comparable to sand‐bed structures formed from stationary and upstream migrating waves in flume experiments, confirming the diagnostic value of these structures. Using mean lens length in the event deposit underestimated peak flow conditions during the flood and implied that the lenses were preserved during waning flow.  相似文献   
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