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91.
When confronted with the demands of global climate change, what causes some policy-makers to move the climate adaptation agenda forward in their communities, while others seemingly get little accomplished? To answer this question, we first discuss work on policy-drivers in a coupled human–natural systemic context. This summary review of past research helps us develop a set of competing and complementary explanations for why some communities aggressively pursue climate adaptation policies, while others do less. Following the discussion of policy-drivers, we then undertake an aggregate-level analysis of data collected across the 169 towns in Connecticut regarding climate adaptation, thus linking policy to its fundamental global cause. The quantitative data are augmented with interview data from policy-makers and activists from around the New England region.  相似文献   
92.
Opponents of a proposed sea-level-rise policy in North Carolina, USA, reasoned rhetorically to promote a narrative claiming that the policy supporters’ efforts had failed to meet the criteria of “good” science and the American dream expectancy of “progress.” The critics worked to hinder policy adoption by naming as “villains” scientists who provided research to support the proposed policy. In addition, the opponents named their own efforts to prevent policy based on “bad” science that would “destroy” the American dream as “heroic.” To more effectively respond to such narratives, scientists and policy proponents need to shift away from reporting just climate change “facts” in the attempt to gain stakeholder support for mitigation and adaptation initiatives. They need to move toward reasoning rhetorically to construct narratives that encourage the public to name them as the “heroes” who will achieve the American dream by their actions to mitigate climate-change outcomes.  相似文献   
93.
Variability and trends in water‐year runoff efficiency (RE) — computed as the ratio of water‐year runoff (streamflow per unit area) to water‐year precipitation — in the conterminous United States (CONUS) are examined for the 1951 through 2012 period. Changes in RE are analyzed using runoff and precipitation data aggregated to United States Geological Survey 8‐digit hydrologic cataloging units (HUs). Results indicate increases in RE for some regions in the north‐central CONUS and large decreases in RE for the south‐central CONUS. The increases in RE in the north‐central CONUS are explained by trends in climate, whereas the large decreases in RE in the south‐central CONUS likely are related to groundwater withdrawals from the Ogallala aquifer to support irrigated agriculture.  相似文献   
94.
Climate change adaptation is an important part of addressing climate warming. Inner Mongolia grassland is a sensitive and vulnerable area of climate and an important region for adaptation to climate change. New climate change adaptation approaches with nomadic culture characteristics should be exploded in the context of climate warming. In this paper, the different utilization pattern of grassland in different regions, the different modes of production and management and historical culture were analyzed first in Nenjiang–West Liaohe plain and Ke’erqin region, Inner Mongolia Plateau and Ordos Plateau. Then, nomadic culture on the grassland was discussed from the productivity to biodiversity, from local livestock variety to resource-used system. Finally, new approaches of climate change adaptation with inheriting the essence of nomadic culture were proposed, including protecting biodiversity and using resources reasonably, performing a practice of grazing suspension–rotational grazing system, fencing degenerated grassland to facilitate its growth, founding new farming and husbandry system on the grassland, and establishing an incentive mechanism favorable to grassland and ethical cultural protection.  相似文献   
95.
Agroforestry systems have substantial potential to conserve native biodiversity and provide ecosystem services. In particular, agroforestry systems have the potential to conserve native tree diversity and sequester carbon for climate change mitigation. However, little research has been conducted on the temporal stability of species diversity and aboveground carbon stocks in these systems or the relation between species diversity and aboveground carbon sequestration. We measured changes in shade‐tree diversity and shade‐tree carbon stocks in 14 plots of a 35‐ha coffee cooperative over 9 years and analyzed relations between species diversity and carbon sequestration. Carbon sequestration was positively correlated with initial species richness of shade trees. Species diversity of shade trees did not change significantly over the study period, but carbon stocks increased due to tree growth. Our results show a potential for carbon sequestration and long‐term biodiversity conservation in smallholder coffee agroforestry systems and illustrate the opportunity for synergies between biodiversity conservation and climate change mitigation. Interacciones entre el Secuestro de Carbono y la Diversidad de Árboles de Sombra en una Cooperativa de Café de Pequeños Agricultores en El Salvador  相似文献   
96.
分析陕西省2000年天气气候变化发现,隆冬降雪明显增多,春旱异常严重,秋霖明显,沙尘暴天气明显增加,这是多年来未曾见到的现象。异常的天气气候使得多种自然灾害并发。  相似文献   
97.
Abstract: Avian conservation efforts must account for changes in vegetation composition and structure associated with climate change. We modeled vegetation change and the probability of occurrence of birds to project changes in winter bird distributions associated with climate change and fire management in the northern Chihuahuan Desert (southwestern U.S.A.). We simulated vegetation change in a process‐based model (Landscape and Fire Simulator) in which anticipated climate change was associated with doubling of current atmospheric carbon dioxide over the next 50 years. We estimated the relative probability of bird occurrence on the basis of statistical models derived from field observations of birds and data on vegetation type, topography, and roads. We selected 3 focal species, Scaled Quail (Callipepla squamata), Loggerhead Shrike (Lanius ludovicianus), and Rock Wren (Salpinctes obsoletus), that had a range of probabilities of occurrence for our study area. Our simulations projected increases in relative probability of bird occurrence in shrubland and decreases in grassland and Yucca spp. and ocotillo (Fouquieria splendens) vegetation. Generally, the relative probability of occurrence of all 3 species was highest in shrubland because leaf‐area index values were lower in shrubland. This high probability of occurrence likely is related to the species’ use of open vegetation for foraging. Fire suppression had little effect on projected vegetation composition because as climate changed there was less fuel and burned area. Our results show that if future water limits on plant type are considered, models that incorporate spatial data may suggest how and where different species of birds may respond to vegetation changes.  相似文献   
98.
Long-term changes, from 1984 to 2010, in the indicators of microbial pollution (total viable count, coliforms, Escherichia coli, enterococci, and Clostridium perfringens) are analysed in the Riga Hydropower Plant Reservoir, an essential source of drinking water for Riga, the capital of Latvia. Counts in microbial indicators fluctuated seasonally and were related to physicochemical parameters (nitrogen compounds, turbidity, temperature, and pH). The changes in microbial pollution were brought about by two major socio-economic developments. Firstly, Latvia’s independence from the USSR in 1991 which facilitated a distinct reduction in most microorganism counts due to a sharp decline in industrial and agricultural production. This resulted in a significant drop in point and nonpoint pollution in the river basin. A further development was Latvia joining the European Union in 2004. The corresponding focus on water management, including wastewater treatment, was a major priority of environmental investment and lead to improvements in microbial water quality.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01470-1) contains supplementary material, which is available to authorized users.  相似文献   
99.
中国城市热岛时空特征及其影响因子的分析   总被引:9,自引:6,他引:3  
曹畅  李旭辉  张弥  刘寿东  徐家平 《环境科学》2017,38(10):3987-3997
全球气候变暖背景下,城市热岛效应会加重城市地区的热胁迫,对人类健康和生存发展提出严峻挑战.近年来我国雾-霾污染情况严重,但雾-霾对城市热岛影响的认识仍较匮乏.本研究基于MODIS遥感卫星地表温度数据,明确了我国2003~2013年白天、夜间以及四季城市热岛的空间变化,并从生物物理学和生物化学角度定量分析其控制机制.结果表明,影响我国白天城市热岛强度的主要因素为人口、农田灌溉和植被活动.纬度、降水量、反照率以及气溶胶浓度是夜间城市热岛强度的主控因子.从对比城乡粗糙度、反照率等生物物理学属性的角度,揭示了乡村背景环境对城市热岛分析的重要影响.结果表明,雾-霾治理可以缓解我国夜间城市热岛现象和热胁迫,有利于缓解区域甚至全球气候变化.  相似文献   
100.
模拟气候升温对湿地土壤微生物群落及磷素形态的影响   总被引:1,自引:1,他引:0  
通过构建微宇宙湿地柱模拟气候升温的方法,采用高通量测序和核磁共振技术,分别研究了湿地土壤微生物群落和磷素形态对暖化作用的响应特征.结果表明,暖化作用导致了Firmicutes、Clostridia、Clostridiales、Clostridiaceae和Clostridium的相对丰度分别显著下降65%~98%、69%~87%、67%~87%、73%~97%和74%~93%,这表明暖化作用对不同分类水平上的物种Firmicutes到Clostridium具有显著的抑制效应.通过主坐标分析和聚类分析,不同湿地柱采样点的暖化组与对照组样本表现出显著的分离特征,揭示了暖化作用能够诱导微生物群落组成发生显著性变化.磷酸单酯和正磷酸盐是各湿地柱土壤主导的磷素形态,同时暖化作用导致了XX湿地柱采样点的磷酸单酯和正磷酸盐相对丰度分别显著升高275%和下降20%,JH湿地柱采样点的磷酸单酯和多聚磷酸盐相对丰度分别显著升高85%和下降49%,这表明不同磷素形态对暖化作用的响应具有土壤异质性特征.通过典型对应分析,揭示了暖化条件下微生物群落组成的显著变化对磷素形态具有显著的影响效应.  相似文献   
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