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971.
The Bali Action Plan and Cancun agreements on Reducing Emissions from Deforestation and forest Degradation, plus forest conservation, sustainable management of forests and enhancement of forest carbon stocks (REDD+) have encouraged demonstration activities as part of Readiness and a step towards national approaches. This has enabled important growth in pilot and demonstration projects. Yet an understanding about how these projects are connected and contribute to national-level technical, policy, and institutional preparedness (Readiness) for REDD+ is lacking. This article examines the linkages between national processes and the private-sector-driven Kasigau Corridor REDD+ project in Kenya. The study reveals interesting cross-scale interactions that have increased over time and have high potential for harnessing national-level processes through lessons from the project level. Key innovations from the Kasigau Corridor Project include the implementation of REDD+ in dry forests, operationalization of conservation easements in the context of REDD+, and demonstration of potential ways of obtaining upfront finance for REDD+. The study also provides a number of key recommendations for Kenya and REDD+ in general, including official endorsement of stand-alone REDD+ projects under national Readiness schemes and exploring jurisdictional and nested REDD+ approaches. Additionally, more accommodating national-level frameworks for attracting private-sector engagement and investments, and for integrating, scaling-out, or scaling-up lessons from such projects, would be needed to enhance national REDD+ Readiness. 相似文献
972.
Nicolas Kolodziejczyk Frédéric Marin Bernard Bourlès Yves Gouriou Henrick Berger 《Climate Dynamics》2014,43(11):3025-3046
The termination of the Equatorial Undercurrent (EUC) in the eastern equatorial Atlantic during boreal summer and fall, and the fate of the associated saline water masses, are analyzed from in situ hydrological and currents data collected during 19 hydrographic cruises between 2000 and 2007, complemented by observations from Argo profiling floats and PIRATA moorings, and from a numerical simulation of the Tropical Atlantic Ocean for the period 1993–2007. An intense variability of the circulation and hydrological properties is evidenced from observations in the upper thermocline (24.5–26.2 isopycnal layer) between June and November. During early boreal summer, saline water masses are transported eastward in the upper thermocline to the African coast within the EUC, and recirculate westward on both sides of the EUC. In mid-boreal summer, the EUC weakens in the upper thermocline and the equatorial salinity maximum disappears due to intense mixing with the surface waters during the upwelling season. The extra-equatorial salinity maxima are also partially eroded during the boreal summer, with a slight poleward migration of the southern hemisphere maximum until late boreal summer. The upper EUC reappears in September, feeding again the eastern equatorial Atlantic with saline waters until boreal spring. During December–January, numerical results suggest a second seasonal weakening of the EUC in the Gulf of Guinea, with a partial erosion of the associated equatorial salinity maximum. 相似文献
973.
Eric Kergosien Bernard Laval Mathieu Roche 《International journal of geographical information science》2014,28(4):739-762
A great deal of research on information extraction from textual datasets has been performed in specific data contexts, such as movie reviews, commercial product evaluations, campaign speeches, etc. In this paper, we raise the question on how appropriate these methods are for documents related to land-use planning. The kind of information sought concerns the stakeholders, sentiments, geographic information, and everything else related to the territory. However, it is extremely challenging to link sentiments to the three dimensions that constitute geographic information (location, time, and theme). After highlighting the limitations of existing proposals and discussing issues related to textual data, we present a method called OPILAND (OPinion mIning from LAND-use planning documents) designed to semi-automatically mine opinions related to named-entities in specialized contexts. Experiments are conducted on a Thau lagoon dataset (France), and then applied on three datasets that are related to different areas in order to highlight the relevance and the broader applications of our proposal. 相似文献
974.
This paper presents an example of the application of error monitoring techniques to the results of a pseudodynamic test performed at variable testing speeds. For the faster testing speeds, the control errors increased and the test reliability was lost in terms of accuracy and stability, as observed by the evolution of the monitoring parameters. The applied monitoring methods were the spatial model identification of frequency and damping distortions and the error energy, which have been proposed in previous publications. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
975.
Connie Chapman Ian J. Walker Patrick A. Hesp Bernard O. Bauer Robin G. D. Davidson‐Arnott Jeff Ollerhead 《地球表面变化过程与地形》2013,38(14):1735-1747
Reynolds shear stress (RS = –u′ w′) and sand transport patterns over a vegetated foredune are explored using three‐dimensional velocity data from ultrasonic anemometers (at 0 · 2 and 1 · 2 m) and sand transport intensity from laser particle counters (at 0 · 014 m). A mid‐latitude cyclone on 3–4 May 2010 generated storm‐force winds (exceeding 20 m s–1) that shifted from offshore to obliquely alongshore. Quadrant analysis was used to characterize the spatial variation of RS quadrant components (Q1 through Q4) and their relative contributions were parameterized using the flow exuberance relation, EXFL = (Q1 + Q3)/(Q2 + Q4). The magnitudes of RS and sand transport varied somewhat independently over the dune as controlled by topographic forcing effects on flow dynamics. A ‘flow exuberance effect’ was evident such that Q2 (ejection‐like) and Q4 (sweep‐like) quadrants (that contribute positively to RS) dominated on the beach, dune toe, and lower stoss, whereas Q1 and Q3 (that contribute negatively to RS) dominated near the crest. This exuberance effect was not expressed, however, in sand transport patterns. Instead, Q1 and Q4, with above‐average streamwise velocity fluctuations (+u′), were most frequently associated with sand transport. Q4 activity corresponded with most sand transport at the beach, toe, and stoss locations (52, 60, 100%). At the crest, 25 to 86% of transport was associated with Q1 while Q4 corresponded with most of the remaining transport (13 to 59%). Thus, the relationship between sand transport and RS is not as straightforward as in traditional equations that relate flux to stress in increasing fashion. Generally, RS was poorly associated with sand transport partly because Q1 and Q4 contributions offset each other in RS calculations. Thus, large amounts of transport can occur with small RS. Turbulent kinetic energy or Reynolds normal stresses (u′2, w′2) may provide stronger associations with sand transport over dunes, although challenges exist on how to normalize and compare these quantities. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
976.
977.
Crystallization experiments have been conducted on compositions along tholeiitic liquid lines of descent to define the compositional space for the development of silicate liquid immiscibility. Starting materials have 46–56 wt% SiO2, 11.7–17.7 wt% FeOtot, and Mg-number between 0.29 and 0.36. These melts fall on the basaltic trends relevant for Mull, Iceland, Snake River Plain lavas and for the Sept Iles layered intrusion, where large-scale liquid immiscibility has been recognized. At one atmosphere under anhydrous conditions, immiscibility develops below 1,000–1,020°C in all of these compositionally diverse lavas. Extreme iron enrichment is not necessary; immiscibility also develops during iron depletion and silica enrichment. Variations in melt composition control the development of silicate liquid immiscibility along the tholeiitic trend. Elevation of Na2O + K2O + P2O5 + TiO2 promotes the development of two immiscible liquids. Increasing melt CaO and Al2O3 stabilizes a single-liquid field. New data and published phase equilibria show that anhydrous, low-pressure fractional crystallization is the most favorable condition for unmixing during differentiation. Pressure inhibits immiscibility because it expands the stability field of high-Ca clinopyroxene, which reduces the proportion of plagioclase in the crystallizing assemblage, thus enhancing early iron depletion. Magma mixing between primitive basalt and Fe–Ti–P-rich ferrobasalts can serve to elevate phosphorous and alkali contents and thereby promote unmixing. Water might decrease the temperature and size of the two-liquid field, potentially shifting the binodal (solvus) below the liquidus, leading the system to evolve as a single-melt phase. 相似文献
978.
979.
Bernard D. Zetler 《Marine Geodesy》2013,36(3):237-248
Abstract The tides at Port Mansfield are so small (mean diurnal range of about 2 cm) that they are nearly lost in a noisy (meteorological) continuum. Nevertheless, a precise tidal analysis is necessary to provide the data for a determination of the elevation of mean high water, the boundary between private and state ownership in an oil‐producing area with a very flat terrain. Although response tidal analysis has been shown to be somewhat superior to classical harmonic analysis in various previous tests, no advantage is found in these circumstances of extremely low sighal‐to‐noise ratio. 相似文献
980.
Bernard Charlier Olivier Namur Simon Malpas Cédric de Marneffe Jean-Clair Duchesne Jacqueline Vander Auwera Olivier Bolle 《Lithos》2010,117(1-4):119-134
The late-Proterozoic Allard Lake ilmenite deposit is located in the Havre-Saint-Pierre anorthosite complex, part of the allochtonous polycyclic belt of the Grenville Province. Presently the world's largest Fe–Ti oxide deposit, it had a pre-mining amount in excess of 200 Mt at grades over 60 wt.% hemo-ilmenite. The main ore body is a funnel-shaped intrusion, measuring 1.03 × 1.10 km and 100–300 m-thick. Two smaller bodies are separated by faults and anorthosite. The ore is an ilmenite-rich norite (or ilmenitite) made up of hemo-ilmenite (Hem22.6–29.4, 66.2 wt.% on average), andesine plagioclase (An45–50), aluminous spinel and locally orthopyroxene. Whole-rock chemical compositions are controlled by the proportions of ilmenite and plagioclase ± orthopyroxene which supports the cumulate origin of the deposit. Ore-forming processes are further constrained by normal and reverse fractionation trends of Cr concentration in cumulus ilmenite that reveal multiple magma emplacements and alternating periods of fractional crystallization and magma mixing. Mixing of magmas produced hybrids located in the stability field of ilmenite resulted in periodic crystallization of ilmenite alone. The unsystematic differentiation trends in the Allard Lake deposit, arising from a succession of magma pulses, hybridisation, and the fractionation of hemo-ilmenite alone or together with plagioclase suggest that the deposit formed within a magma conduit. This dynamic emplacement mechanism associated with continuous gravity driven accumulation of Fe–Ti oxides and possibly plagioclase buoyancy in a fractionating ferrobasalt explains the huge concentration of hemo-ilmenite. The occurrence of sapphirine associated with aluminous spinel and high-alumina orthopyroxene (7.6–9.1 wt.% Al2O3) lacking exsolved plagioclase supports the involvement of a metamorphic overprint during the synchronous Ottawan orogeny, which is also responsible for strong textural equilibration and external granule of exsolved aluminous spinel due to slow cooling. 相似文献