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Integrated estimates of global terrestrial carbon sequestration   总被引:1,自引:0,他引:1  
Assessing the contribution of terrestrial carbon sequestration to climate change mitigation requires integration across scientific and disciplinary boundaries. A comprehensive analysis incorporating ecologic, geographic and economic data was used to develop terrestrial carbon sequestration estimates for agricultural soil carbon, reforestation and pasture management. These estimates were applied in the MiniCAM integrated assessment model to evaluate mitigation strategies within policy and technology scenarios aimed at achieving atmospheric greenhouse gas stabilization by 2100. Terrestrial sequestration reaches a peak rate of 0.5–0.7 GtC yr−1 in mid-century with contributions from agricultural soils (0.21 GtC yr−1), reforestation (0.31 GtC yr−1) and pasture (0.15 GtC yr−1). Sequestration rates vary over time and with different technology and policy scenarios. The combined contribution of terrestrial sequestration over the next century ranges from 23 to 41 GtC.  相似文献   
154.
Leon Sheleff 《GeoJournal》2001,53(3):297-309
Jewish tradition refers to the city of Jerusalem in both abstract and concrete terms, celestial Jerusalem and earthly Jerusalem. The two are intricately bound up with each other and Jerusalem, the eternal capital city of the Jewish people, derives its powerful mystique, from its original appearance in Jewish history, although Biblical Jerusalem, the ancient city surrounded by hills, and modern Jerusalem, the capital city of Israel, surrounded by satellite urban appendages, lack geographical congruity. In general, this is geo-politically relevant given the potent sensitivities that most Jews in Israel and elsewhere have for the symbolic value of their ancient capital. Significantly, most of the Arab inhabitants the capital city of Israel, are not Israeli citizens and the vast majority of them refuse to participate in municipal elections, even though Israeli law allows non-citizens who are permanent residents to vote in local elections. That Israel permits several countries to maintain separate consulates, in the western and eastern parts of Israel's capital, indicates Israel's implicit recognition of a dual status in Jerusalem. After the 1967 war, while careful to avoid using the formal language of annexation, Israel generally considered that east Jerusalem and some surrounding areas had become part of Israel, when by Basic Law: Jerusalem, the Capital City, it was declared to be the united and eternal capital of the State of Israel. This paper examines these political and legal developments.  相似文献   
155.
Granulite facies gabbroic and dioritic gneisses in the Pembroke Valley, Milford Sound, New Zealand, are cut by vertical and planar garnet reaction zones in rectilinear patterns. In gabbroic gneiss, narrow dykes of anorthositic leucosome are surrounded by fine‐grained garnet granulite that replaced the host two‐pyroxene hornblende granulite at conditions of 750 °C and 14 kbar. Major and trace element whole‐rock geochemical data indicate that recrystallization was mostly isochemical. The anorthositic veins cut contacts between gabbroic gneiss and dioritic gneiss, but change in morphology at the contacts, from the anorthositic vein surrounded by a garnet granulite reaction zone in the gabbroic gneiss, to zones with a septum of coarse‐grained garnet surrounded by anorthositic leucosome in the dioritic gneiss. The dioritic gneiss also contains isolated garnet grains enclosed by leucosome, and short planar trains of garnet grains linked by leucosome. Partial melting of the dioritic gneiss, mostly controlled by hornblende breakdown at water‐undersaturated conditions, is inferred to have generated the leucosomes. The form of the leucosomes is consistent with melt segregation and transport aided by fracture propagation; limited retrogression suggests considerable melt escape. Dyking and melt escape from the dioritic gneiss are inferred to have propagated fractures into the gabbroic gneiss. The migrating melt scavenged water from the surrounding gabbroic gneiss and induced the limited replacement by garnet granulite.  相似文献   
156.
Chatwin and Sullivan (1990) proposed simple results for the relationships between moments of scalar fluctuations in self-similar turbulent shear flows. They showed these relationships to be well satisfied by observations from a range of experiments. Here their theory is extended to the skewness, kurtosis and higher order equivalents. It is shown that the relationships between these normalised moments are parameter-free, and are identical to those for zero molecular diffusion. Experimental observations are presented which show a remarkable degree of collapse when these normalised moments are plotted against each other. The agreement with the theoretical results is reasonably good, and better than for some other standard statistical distributions which are commonly applied to such observations. This is true not only for the concentration, but also for generalised doses. It is concluded that the simple theory provides a satisfactory basis for a model of both the concentration and of dose. Furthermore, the results suggest that the concentration and the dose can be modelled through a perturbation to a two-state model.  相似文献   
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