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71.
72.
Sue Wells Melita Samoilys Solomon Makoloweka Hassan Kalombo 《Ocean & Coastal Management》2010,53(4):161-168
The Tanga Coastal Zone Conservation and Development Programme, initiated in 1994, was among the first such projects to make livelihoods improvement a key objective, and to use a community-based approach. It developed an approach to coastal management planning that is broadly satisfactory to both communities and the government. Six fisheries management areas and two mangrove management areas were established. Institutional arrangements for the collaborative approach were strengthened and community leaders and local government officers were trained in a range of relevant skills. A coastal environmental education programme for primary schools involved several thousand schoolchildren, and a gender programme built the confidence of women. Implementation of the management measures was noticeably harder than planning, particularly elimination of destructive fishing methods. Fishers and coastal communities now however have a much greater involvement in, and understanding of, coastal management and consequently a greater sense of ownership. 相似文献
73.
Franz E. Sueß 《International Journal of Earth Sciences》1921,11(5-6):249-263
Ohne Zusammenfassung 相似文献
74.
75.
Arch M. Reid R. W. Brown J. B. Dawson G. G. Whitfield J. C. Siebert 《Contributions to Mineralogy and Petrology》1976,58(2):203-220
Analyses are reported for garnet and pyroxene from 17 eclogites that contain diamond. The garnets contain small but significant contents of Na, Ti and P and the pyroxenes contain traces of K. The diamond-bearing eclogites do not constitute a unique compositional group but show a range of mineral compositions consistent with a very high P-T environment. 相似文献
76.
77.
Garnet peridotite xenoliths in South African kimberlite pipes and their petrogenesis 总被引:1,自引:0,他引:1
Whole rock analyses are presented for nine garnet peridotite, two garnet pyroxenite, one garnet free peridotite and two highly altered garnet peridotite xenoliths from South African kimberlite pipes. Garnets from eight of these samples have also been chemically analysed, while olivine compositions in the twelve fresh samples have been estimated by X-ray diffraction. The chemistry and mineralogy of these specimens are compared with the results of previous studies, and the controversies concerning the petrogenesis of these xenoliths are discussed in detail. 相似文献
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79.
Lindsay P. Keller Scott Messenger George J. Flynn Sue Wirick 《Geochimica et cosmochimica acta》2004,68(11):2577-2589
Eight interplanetary dust particles (IDPs) exhibiting a wide range of H and N isotopic anomalies have been studied by transmission electron microscopy, x-ray absorption near-edge structure spectroscopy, and Fourier-transform infrared spectroscopy. These anomalies are believed to have originated during chemical reactions in a cold molecular cloud that was the precursor to the Solar System. The chemical and mineralogical studies reported here thus constitute direct studies of preserved molecular cloud materials. The H and N isotopic anomalies are hosted by different hydrocarbons that reside in the abundant carbonaceous matrix of the IDPs. Infrared measurements constrain the major deuterium (D) host in the D-enriched IDPs to thermally labile aliphatic hydrocarbon groups attached to macromolecular material. Much of the large variation observed in D/H in this suite of IDPs reflects the variable loss of this labile component during atmospheric entry heating. IDPs with elevated 15N/14N ratios contain N in the form of amine (-NH2) functional groups that are likely attached to other molecules such as aromatic hydrocarbons. The host of the N isotopic anomalies is not as readily lost during entry heating as the D-rich material. Infrared analysis shows that while the organic matter in primitive anhydrous IDPs is similar to that observed in acid residues of primitive chondritic meteorites, the measured aromatic:aliphatic ratio is markedly lower in the IDPs. 相似文献
80.
We analyzed the isotopic patterns found in the tooth enamel of modern feral horses from Shackleford Banks, North Carolina (USA), which has a temperate climate and supports primarily C4 grasslands. Enamel δ13C values averaged −4.1‰ with a standard deviation (1σ) of 1.7‰, which corresponds to an average diet of 66 ± 12% C4 plants. Our results differ from dietary reconstructions from 1978 to 1981, which found that horses consumed 91% C4 plants. This suggests that horses have increased their consumption of C3 forbs, likely as a result of the removal of cattle, sheep, and goats from the island. Shackleford surface waters had δ18O values that averaged −3.3 ± 0.5‰ and −1.3 ± 1.8‰ on the western and eastern ends of the island, respectively. Tooth enamel samples averaged 27.3 ± 1.5‰ and displayed the same range of δ18O values as surface waters. The variability of both δ18O and the δ13C values among individuals within this population demonstrates that horses from relatively homogenous temperate environments can display a wide range of isotopic values. Given the observed range of isotopic values for modern horses, we suggest that researchers use the mean values of multiple (≥9) equids when attempting to reconstruct average paleodiets and/or paleoenvironmental conditions. 相似文献