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341.
适应信息通报作为《巴黎协定》下联结国家个体适应行动、全球适应目标以及全球集体适应努力的纽带,是目前《巴黎协定》特设工作组（APA）下唯一的适应议题,会对未来全球适应气候变化的政策和行动产生较大影响。本文总结了APA适应信息通报的谈判进程和最新进展,梳理了不同缔约方和谈判集团对适应信息通报目的、内容、报告渠道、指南和灵活性的立场和观点,展望了适应信息通报未来的谈判走势。中国与大多数发展中国家相比,开展适应行动及提供信息报告的能力较强,在适应信息通报谈判中立场相对灵活,但未来在有关适应的资金支持谈判等方面仍面临着压力,建议推动和深化适应气候变化领域南南合作以团结更多发展中国家,促进全球适应行动,回应发展中国家的关切。 相似文献
342.
India has 64 Mha under forests, of which 72% are tropical moist deciduous, dry deciduous, and wet evergreen forest. Projected changes in temperature, rainfall, and soil moisture are considered at regional level for India under two scenarios, the first involving greenhouse gas forcing, and the second, sulphate aerosols. Under the former model, a general increase in temperature and rainfall in all regions is indicated. This could potentially result in increased productivity, and shift forest type boundaries along attitudinal and rainfall gradients, with species migrating from lower to higher elevations and the drier forest types being transformed to moister types. The aerosol model, however, indicates a more modest increase in temperature and a decrease in precipitation in central and northern India, which would considerably stress the forests in these regions.Although India seems to have stabilized the area under forest since 1980, anthropogenic stresses such as livestock pressure, biomass demand for fuelwood and timber, and the fragmented nature of forests will all affect forest response to changing climate. Thus, forest area is unlikely to expand even if climatically suitable, and will probably decrease in parts of northeast India due to extensive shifting cultivation and deforestation. A number of general adaptation measures to climate change are listed. 相似文献
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研究太湖冬季底泥和经过处理后的底泥中活体微囊藻 (Microcystisspp .)细胞的数量 ,并将分离出来的微囊藻经过低温 (3～ 4℃ )、高温 (>38℃ )、干燥、无光等处理 ,探讨了太湖微囊藻对不良环境的适应 ,为研究太湖藻类季节性变化规律和微囊藻水华的爆发机理。结果表明 ,微囊藻能在低温、高温、干燥、低光或无光的环境中长时间生存 ,条件适宜时又能快速增殖。这些特性使得微囊藻不仅具备良好的环境适应性和耐受性 ,而且具备良好的传播和增殖能力。讨论了微囊藻对不良环境的适应与其在水华中的优势地位的相关性。 相似文献
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In order to address the pressing challenge of climate change, countries are now submitting long-term climate strategies to the United Nations Framework Convention on Climate Change (UNFCCC) process. These strategies include within them potential future use of ‘negative emissions technologies’ (NETs). NETs are interventions that remove carbon from the atmosphere, ranging from large-scale terrestrial carbon sequestration in forests, wetlands and soils, to use of carbon capture and storage technologies. We assess here how NETs are discussed in 29 long-term climate strategies, in order to ascertain the risk that including the promise of future NETs may delay the taking of short-term mitigation actions. Our analysis shows that almost all countries plan to rely on NETs, particularly enhanced use of natural carbon sinks, even as a wide array of challenges and trade-offs in doing so are highlighted. Many strategies call for improved accounting systems and market incentives in realizing future NETs. While no strategy explicitly suggests that NETs can be a substitute for short-term mitigation, most estimate substantial potential for future use of NETs even in the face of acknowledged uncertainties. This, we suggest, may have the consequence of resulting in what we describe here as ‘a spiral of delay’ characterized by the promise of future NET options juxtaposed with the simultaneous uncertainty around these future options. Our analysis highlights that this inter-connected delaying dynamic may be intrinsic to what we term ‘governing-by-aspiration’ within global climate politics, wherein the voicing of lofty future ambition risks replacing current action and accountability. 相似文献
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Sustainable management of ecosystem services requires knowledge of both natural and human systems, but the adaptive behaviors of human harvesters in response to management changes and environmental variability are poorly understood. Given the specter of accelerating climate change, it is especially critical to understand how human harvesters may respond to environmental perturbation. In this study, we identify characteristics that promoted resilience of one the most valuable fisheries on the west coast of the United States to a record marine heatwave. Using movement telemetry linked to Dungeness crab fishery landings records from more than 500 fishing vessels, encompassing 2.2 million geolocations and more than USD two billion in revenue, we found that commercial fishing vessels employed two, non-mutually exclusive strategies to cope with the anomalous environmental and management conditions imposed by the heatwave: increasing spatial mobility and diversifying fishery participation. The combination of these strategies appeared to be the most adaptive, as it produced the greatest increase in Dungeness crab profits. In contrast, participants that specialized in a single fishery and concentrated fishing effort in small spatial areas did not perform as well. Our data-driven approach reveals behaviors that can be promoted to improve the adaptive capacity of human harvesters in an era of unprecedented environmental perturbation. 相似文献