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Carbon and total suspended sediment (TSS) loads were investigated from April 2006 to March 2008 in the mountainous watershed of the Isère River, French Alps (5570 km2). The river bed has been highly impounded for hydroelectricity production during the last century. Hydraulic flushes are managed every year to prevent TSS storage within upstream dams. The Isère River has been instrumented for high‐frequency monitoring of water, TSS by turbidity and carbon (organic, inorganic, dissolved and particulate) in order to evaluate the impact of natural floods and hydraulic flushes on annual loads. Annual TSS load which was estimated between 1.3 and 2.3 MT y?1 (i.e. 233 to 413 T km?2 y?1) highlighted the high erodibility of the Isère watershed. Annual carbon load was estimated between 173 103 T y?1 and 199 103 T y?1 (i.e 31 to 36 T km?2 y?1). About 80% of the annual carbon loads were inorganic. The impact of hydraulic flushes on annual loads appeared limited (less than 3% for annual TSS load and about 1.5% for annual carbon load), whereas the most important natural flood event contributed to 20% of the annual TSS load and 10% of the annual carbon load. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
64.
Investments in adaptation are required to reduce vulnerability and strengthen the resilience of food systems to the impacts of climate change. For low-income nations, international financing plays a central role in supporting adaptation. In this article, we document and examine adaptation projects targeting food systems financed through funding bodies of the United Nations Framework Convention on Climate Change (UNFCCC). We find that between 2004 and 2015, 3% (n?=?96) of adaptation projects supported through the UNFCCC explicitly focused on the production, processing, distribution, preparation and/or consumption of food, with US$546 m mobilized through funding bodies directly and US$1.44bn through co-financing. Agriculture is the most common sector supported, with extreme weather events the primary climate change-related impact motivating nations to apply for adaptation financing. The majority of actions are documented to adapt the food production component of food systems, with limited focus within projects on the full range of food system vulnerability and the implications on food security.

Key policy insights
  • Enhanced international adaptation financing targeting food systems is needed, and in particular financing to address limited adaptation readiness

  • Supported food system projects should include holistic assessments of the entire food system in order to prioritize sector and food system component issue areas for short- and long-term efficiency

  • To better analyse food system linkages and aid in the prioritization of adaptation activities, adaptation-directed funds should consider placing a higher emphasis on a cross-sectoral approach within projects

  • Linkages between official development assistance and adaptation-directed funds could help optimize financing for food systems and mainstream food system adaptation efforts

  相似文献   
65.
Intellectual property rights (IPRs) and the transfer of low carbon technologies to developing countries have been the focus of sustained disagreement between many developed and developing country Parties to the United Nations Framework Convention on Climate Change (UNFCCC). We argue that this disagreement stems from two conflicting political discourses of economic development and low carbon technology diffusion which tend to underpin developing and developed countries’ respective motivations for becoming party to the Convention. We illustrate the policy implications of these discourses by examining empirical evidence on IPRs and low carbon technology transfer and highlight how the two discourses are based on an incomplete understanding of the role of technological capacity in either economic development or technology diffusion. This has important implication for the success of post-2012 international climate agreements.  相似文献   
66.
The high pressure spinel polymorph of Ni2SiO4 persists metastably at 713°C and atmospheric pressure. The enthalpy of the olivine-spinel transition was obtained by measuring the heats of solution of both polymorphs in a molten oxide solvent, 2PbO · B2O3, at that temperature. For Ni2SiO4(ol)→Ni2SiO4, ΔH9860 = +1.4 ± 0.7kcal/mol. The heat content increments, H986 ? H297, were found to be: olivine, 25.73 ± 0.42kcal/mol, and spinel, 25.39 ± 0.20kcal/mol. The measured enthalpy of the transformation is consistent with the low slope of the phase boundary, ?P/?T = ~ 12b/deg, observed by Akimoto and others. The entropy of the olivine-spinel transition in Ni2SiO4 is accordingly about a factor of three smaller in magnitude (ΔS = ~ ?1cal/deg mol) than that for Co2SiO4,Fe2SiO4,Mg2SiO4or Mg2GeO4 (ΔS = ?3to?3.5cal/deg mol).  相似文献   
67.
A calorimetric study of the ilmenite and lithium niobate polymorphs of FeTiO3 was undertaken to assess the high-pressure stabilities of these phases. Ilmenite is known to be the stable phase at ambient pressure, but the lithium niobate form may be a quench phase from a perovskite form which has been previously observed in situ at high pressure.In this study, the lithium niobate phase of FeTiO3 was synthesized from an ilmenite starting material at 15– 16 GPa and 1473 K, using a uniaxial split-sphere high-pressure apparatus (USSA 2000). The energetics of the ilmenite to lithium niobate transformation were investigated through transposed-temperature drop calorimetry. The heat of back-transformation of lithium niobate to ilmenite was measured by dropping the sample in argon from ambient conditions to a temperature where the transformation occurs spontaneously. In drops made at 977 K, an intermediate x-ray amorphous phase was encountered. At 1273 K, the transformation went to completion. A value of -13.5±1.2 kJ/mol was obtained for the heat of transformation.  相似文献   
68.
High-temperature experiments on ferromagnesian compositions have been hampered by the rapid absorption of up to 95% of the original iron by platinum and 40% by silver-palladium capsules. Molybdenum or iron capsule materials can decrease or alleviate iron loss, but restrict oxygen fugacities to values near the iron-wustite buffer. Because Co2+ is stable at fO2 =HM and because the solubility of Co in platinum in this range of fO2 is ~0.05% at temperatures to 1350°C, its use as an analogue for Fe2+ is possible. In addition, experiments simulating various Fe2+ ratios can be easily performed by choosing appropriate Co2+/Fe3+ ratios. The cobalt phases produced possess brilliant and distinctive colors which are valuable aids in optical identification of minute phases. The cobalt analogue hypothesis was tested with atmospheric pressure experiments in air on the cobalt analogue of the 1921 Kilauea basalt at three simulated Fe2+/Fe3+ ratios. The results were compared with those of R.E.T. Hill (1969) for the natural 1921 basalt. The phase relations were the same, with the cobalt system stability fields systematically shifted by about +50°C. Microprobe analysis of olivines and the coexisting glasses indicate that the distribution of Co2+ between olivine and melt is independent of temperature and liquid composition. Although the analogue liquid composition differs from the equilibrium composition of the natural system, it may be corrected be employing distribution coefficients (KD = 0.61 for the Co system; KD = 0.33 for the Fe system) to closely approximate what the natural system would yield if iron loss did not occur.  相似文献   
69.
This formulation of the free energy of mixing in a binary system takes as parameters a Bragg-Williams type cooperative disordering energy and the difference in free energy between different structures for the end-members. Subsolidus phase relations in carbonate systems such as CaCO3—MgCO3 and CdCO3—MgCO3 are calculated. Similar equations also reproduce the topologies of subsolidus phase relations in pyroxenes, including orthopyroxene-clinopyroxene phase boundaries in the enstatitediopside and ferrosilite-hedenbergite systems, the pigeonite-augite solvus, and the stability field of iron-free pigeonite.  相似文献   
70.
The Palei-Aike volcanic field, the southernmost unit of the Patagonian plateau lavas, consists of Pleistocene to Recent alkali olivine basalts petrologically and geochemically similar to alkali basalts from diverse tectonic environments. The Palei-Aike basalts have lower SiO2 and Al2O3 and higher TiO2 and P2O3 than published analyses of other Patagonian plateau basalts. Garnet, garnet + spinel-, and phlogopite-peridotites, not reported from other Patagonian plateau lavas or from elsewhere in South America, are common inclusions within Palei-Aike lavas along with spinel-lherzolite, dunite, granulites, and aluminous clinopyroxene megacrysts. The inclusion of these high-pressure assemblages indicates a mantle origin for the Palei-Aike lavas. The Patagonian plateau lavas are located in a tectonic position similar to back-arc basins, and their origin may be a consequence of subduction. The origin and distinct chemical features of the Palei-Aike basalts may be due in part to thermal or mechanical perturbations of the mantle related to changes in plate boundaries and motions in the vicinity of the unstable trench-transform triple junction formed by the South American, Antarctic and Scotia plates.  相似文献   
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