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In the Epirus region of North-west Greece, spring flows in villages have reduced dramatically over the last few decades, in some cases with serious economic consequences. We argue here that this has resulted from the major reduction of grazing by mountain goats over the same period together with other associated land-use changes. Normally such a contention would be impossible to demonstrate because many different causes could be invoked. However, prior to 1946 culturally homogenous Greek-speaking communities with identical pastoral practices were separated by the closure of the Greek-Albanian border. Changes of spring flow have not occurred on the Albanian side of the border where heavy grazing has continued. In a region such as Greece where pastoralism has continued for thousands of years, the environment had reached an equilibrium with goat grazing. Apart from the reduction of spring flows, other undesirable ecological consequences are occurring.
It is also interesting to note that long-term water table changes such as those occurring in Epirus have been attributed to tectonic effects and thought to potentially predict earthquakes. The effect however, may be the result of goats and other livestock 'leaving' and not the result of earthquakes 'coming'. 相似文献
It is also interesting to note that long-term water table changes such as those occurring in Epirus have been attributed to tectonic effects and thought to potentially predict earthquakes. The effect however, may be the result of goats and other livestock 'leaving' and not the result of earthquakes 'coming'. 相似文献
143.
Fergus Green 《Climatic change》2018,150(1-2):103-116
Historically, climate governance initiatives and associated scholarship have all but ignored the potential for “global moral norms” to bring about changes in the political conditions for global climate mitigation. This is surprising, since global moral norms are widely employed—as both a mode of governance and an analytical framework—in other domains of global governance, from international security to human rights. However, recent national-level fossil fuel divestments, moratoria on new coal mines and bans on gas fracking, among other developments, suggest the promise of global moral norms prohibiting fossil fuel-related activities, which this article terms “anti-fossil fuel norms” (AFFNs). The article interprets recent examples of such activities in the light of international relations theory on moral norms to provide a general framework for understanding how AFFNs originate, spread and affect states. Specifically, the article argues that there are: (i) influential agents that are originating, and likely to continue to originate, AFFNs; and (ii) international and domestic mechanisms by which AFFNs are likely to spread widely among states and have a significant causal effect on the identity-related considerations or rational calculations of states in the direction of limiting or reducing the production or consumption of fossil fuels. The article also shows that, because they spread and affect state behaviour through mechanisms of “international socialization” and domestic “political mobilization”, AFFNs cohere with and build upon the new paradigm of global climate governance crystallized in the Paris Agreement. AFFNs, the article concludes, represent a promising new frontier in climate governance. 相似文献
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William M. Jackson Victor Blunt Hua Lin Martina Green Gregory Olivera William H. Fink Yihan Bao Randall S. Urdahl Fida Mohammad Mansour Zahedi 《Astrophysics and Space Science》1996,236(1):29-47
A unified picture of the photodissociation of theC
2
H radical has been developed using the results from the latest experimental and theoretical work. This picture shows that a variety of electronic states ofC
2 are formed during the photodissociation of theC
2
H radical even if photoexcitation accesses only one excited state. This is because the excited states have many avoided corssings and near intersections where two electronic states come very close to one another. At these avoided crossings and near intersections, the excited radical can hop from one electronic state to another and access new final electronic states of theC
2 radical. The complexity of the excited state surfaces also explains the bimodal rotational distributions that are observed in all of the electronic states studied. The excited states that dissociate through a direct path are limited by dynamics to produceC
2 fragments with a modest amount of rotational energy, whereas those that dissociate by a more complex path have a greater chance to access all of phase space and produce fragments with higher rotational excitation. Finally, the theoretical transition moments and potential energy curves have been used to provide a better estimate of the photochemical lifetimes in comets of the different excited states of theC
2
H radical. The photochemically active states are the 22+, 22II, 32II, and 32+, with photodissociation rate constants of 1.0×10–6, 4.0×10–6, 0.7×10–6, and 1.3×10–6s–1, respectively. These rate constants lead to a total photochemical lifetime of 1.4×105 s. 相似文献
147.
Activity–composition relations for the calculation of partial melting equilibria in metabasic rocks 下载免费PDF全文
E. C. R. Green R. W. White J. F. A. Diener R. Powell T. J. B. Holland R. M. Palin 《Journal of Metamorphic Geology》2016,34(9):845-869
A set of thermodynamic models is presented that, for the first time, allows partial melting equilibria to be calculated for metabasic rocks. The models consist of new activity–composition relations combined with end‐member thermodynamic properties from the Holland & Powell dataset, version 6. They allow for forward modelling in the system NaO–CaO–KO–FeO–MgO–AlO–SiO–HO–TiO–FeO. In particular, new activity–composition relations are presented for silicate melt of broadly trondhjemitic–tonalitic composition, and for augitic clinopyroxene with Si–Al mixing on the tetrahedral sites, while existing activity–composition relations for hornblende are extended to include KO and TiO. Calibration of the activity–composition relations was carried out with the aim of reproducing major experimental phase‐in/phase‐out boundaries that define the amphibolite–granulite transition, across a range of bulk compositions, at ≤13 kbar. 相似文献
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