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221.
Serge Ngendakumana Peter A. Minang Mireille Feudjio Stijn Speelman Patrick Van Damme Zacharie Tchoundjeu 《Climate Policy》2014,14(6):769-787
The reducing emissions from deforestation and forest degradation (REDD+) initiative has emerged in recent years as a mechanism to simultaneously address climate change, biodiversity, and poverty reduction challenges at the margins of tropical forests. Congo Basin countries, including Cameroon, have embraced the opportunities that REDD+ provides, with great expectations. Yet, it needs to be investigated whether the enabling institutional environment, which is required for implementing REDD+, is present. Understanding is still limited on how to build adequate and strong institutional relations that could shape the reforms towards the establishment of efficient emissions reductions schemes. Furthermore, uncertainty remains on the operational mechanisms of REDD+, suggesting that, to catalyse effectiveness, there is a need to come up with a governance model nested in relevant policy frameworks. This study builds on a modified ‘4Is’ framework – Institutions, Interests, Ideas and Information – to analyse REDD+ and explore stakeholders' perceptions on the local forest governance potential. A structural implementation model to optimize the effectiveness of REDD+ is developed. Findings suggest that governments need to review existing policies to take into account participation, local people rights, and information access as a way to stimulate actors' willingness to contribute to emissions reductions and carbon stock increases under REDD+ regimes. 相似文献
222.
一株海洋聚磷菌YSR-3的分离与鉴定 总被引:14,自引:1,他引:13
采用平板分离法,从黄海海域分离到一株聚磷菌,编号为YSR-3,对其进行了部分生理生化特性以及分子特性的研究。结果表明,YSR-3菌体呈杆状,大小为3·5μm×1μm,革兰氏染色阴性,好氧生长;显微镜下观察能运动。最适培养条件为:氯化钠浓度3%,生长温度为24℃,起始pH值为6·5。该菌能在细胞内累积多磷酸盐形成异染粒。16SrDNA鉴定结果表明,YSR-3属于γ-变形菌纲、盐单胞菌属(Halomonas)。与盐单胞菌属中的其他已知种比较,YSR-3具有其特性:对氯霉素和卡那霉素敏感、淀粉水解呈阳性、反硝化和几丁质降解呈阴性、能将葡萄糖作为唯一碳源和能源。 相似文献
223.
Guillaume Dodet Bruno Castelle Gerd Masselink Timothy Scott Mark Davidson France Floc'h Derek Jackson Serge Suanez 《地球表面变化过程与地形》2019,44(1):393-401
The storm sequence of the 2013–14 winter left many beaches along the Atlantic coast of Europe in their most eroded state for decades. Understanding how beaches recover from such extreme events is essential for coastal managers, especially in light of potential regional increases in storminess due to climate change. Here we analyse a unique dataset of decadal beach morphological changes along the west coast of Europe to investigate the post-2013–14 winter recovery. We show that the recovery signature is site specific and multi-annual, with one studied beach fully recovered after 2 years, and the others only partially recovered after 4 years. During the recovery phase, winter waves primarily control the timescales of beach recovery, as energetic winter conditions stall the recovery process whereas moderate winter conditions accelerate it. This inter-annual variability is well correlated with climate indices. On exposed beaches, an equilibrium model showed significant skill in reproducing the post-storm recovery and thus can be used to investigate the recovery process in more detail. © 2018 John Wiley & Sons, Ltd. 相似文献
224.
Bonnie A.B. Blackwell Anne R. Skinner Joel I.B. Blickstein Serge Lebel Helen Y.M. Leung 《Geoarchaeology》2001,16(7):719-761
At Bau de l'Aubesier, Provence, Mousterian artifacts and human teeth occur in inhomogeneous (“lumpy”) sedimentary deposits that include bone and tooth fragments and extensive burnt horizons. Electron spin resonance (ESR) isochron analyses of mammal teeth, which use multiple subsamples with different U concentrations, can measure the external dose rate experienced by the tooth regardless of reworking and sedimentary dose rate changes. Isochron analyses do depend on the U uptake model assumed, but can also identify teeth that have experienced secondary U uptake or leaching. Using 11 teeth from six archaeological layers, the isochrons demonstrate that at least three teeth have experienced secondary uptake. For eight teeth, the U uptake has apparently not followed strictly early (EU), linear (LU), or recent uptake (RU), but more closely approximates LU‐RU. Comparing volumetrically averaged sedimentary geochemistry with thermoluminescent dosimetry suggests that fossil tissues in the sediment have also experienced LU‐RU uptake. LU‐RU uptake can explain standard ESR ages that underestimate the true fossil age. © 2001 John Wiley & Sons, Inc. 相似文献