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21.
In this paper, we investigate how mountain communities perceive and adapt to climatic and environmental change. Primary data were collected at community and household level through in-depth interviews, focus group discussions, and quantitative questionnaires covering 210 households in six villages of the West Karakoram (Hundur and Darkut in the Yasin Valley; Hussainabad, Altit, Gulmit, and Shiskat in the Hunza valley of Gilgit-Baltistan). The relevance of the area with respect to our scopes is manifold. First, this is one of the most extreme and remote mountainous areas of the world, characterized by complex and fragile institutional and social fabrics. Second, this region is one of the focal points of research for the hydro-meteo-climatological scientific community, because of its relevance in terms of storage and variability of water resources for the whole Indus basin, and for the presence of conflicting signals of climate change with respect to the neighboring regions. Third, the extreme hardships due to a changing environment, as well as to the volatility of the social and economic conditions are putting great stress on the local population. As isolating climate change as a single driver is often not possible, community perceptions of change are analyzed in the livelihood context and confronted with multi-drivers scenarios affecting the lives of mountain people. We compare the collected perceptions with the available hydro-climatological data, trying to answer some key questions such as: how are communities perceiving, coping with, and adapting to climatic and environmental change? Which are the most resorted adaptation strategies? How is their perception of change influencing the decision to undertake certain adaptive measures?  相似文献   
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We report data from a yearlong (2006–2007) study of black carbon concentrations ([BC]) measured at 5-min intervals with an Aethalometer in Karachi, Pakistan. Daily mean [BC] varied from about 1 to 15 μg m?3. However, short-term spikes exceeding 40 μg m?3 were common, occurring primarily during the morning and evening rush-hour periods. The [BC] values were highest during November through February, ~10 μg m?3, and lowest during June through September, ~2 μg m?3. Diurnal, seasonal, and day-of-the-week trends are discussed. It is demonstrated that these trends are strongly affected by meteorological patterns. A simple expression is applied to the concentration profiles to separate the effects of meteorological conditions and elucidate the underlying emissions patterns. Daily emissions varied from 14,000 to 22,000 kg of BC per day. When integrated over the year emissions for Karachi Proper were estimated at 6.7 kilometric tons per year and emissions for greater Karachi were 17.5 kilometric tons per year. Folding in the populations of each area yields BC emissions of 0.74 and 1.1 kg per person per year, respectively. Applying the model to previously collected data at Lahore, Pakistan yields emissions during November–January that are around a factor of two higher than those in Karachi, but because the BC measurements in Lahore covered only three months, no estimates of annual emissions were attempted. Given the large populations of these cities the local health impact from PM alone is expected to be severe but because of the high [BC] emissions the impact on the global climate may be equally significant.  相似文献   
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Environmental Science and Pollution Research - The instant endeavor was undertaken to monitor copper (Cu) contents in water, soil, forage, and cow’s blood impacted by heavy automobiles in...  相似文献   
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Environmental Science and Pollution Research - This study utilized the Pooled Mean Group estimator to investigate the effect of renewable energy consumption, electricity consumption, economic...  相似文献   
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Environmental Science and Pollution Research - Biotic invasions can predominantly alter the dynamics, composition, functions, and structure of natural ecosystems. Social insects, particularly ants,...  相似文献   
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Environmental Science and Pollution Research - Bisphenol A [BPA; (CH3)2C(C6H4OH)2] is a synthetic chemical used as a precursor material for the manufacturing of plastics and resins. It gained...  相似文献   
28.
陕北黄土丘陵区不同土地利用方式下土壤碳剖面分布特征   总被引:16,自引:7,他引:9  
黄土高原土层深厚,土壤剖面碳存储受土地利用方式影响明显.为探讨不同土地利用方式对深层土壤碳分布的影响,研究了人工经济林地(陕北米脂)、退耕还林地(神木)和防风固沙林地(榆林榆阳区)0~20.0 m土壤有机碳(SOC)和无机碳(SIC)的分布特征和差异.结果表明,在不同土地利用方式下SOC含量:矮化枣树(2.00 g·kg~(-1))未矮化枣树(1.54 g·kg~(-1))柠条林(0.97 g·kg~(-1))退化人工草地(0.81 g·kg~(-1))樟子松林(0.70 g·kg~(-1))荒草地(0.45 g·kg~(-1)),且各剖面之间SOC含量存在显著性差异(P0.05).在不同土地利用方式下SIC含量:矮化枣树(11.66 g·kg~(-1))≥未矮化枣树(11.59g·kg~(-1))柠条林(9.62 g·kg~(-1))退化人工草地(8.07 g·kg~(-1))樟子松林(4.32 g·kg~(-1))荒草地(0.47 g·kg~(-1));人工经济林和退耕还林(草)样地内所有土壤剖面之间SIC含量无显著性差异;人工经济林、退耕还林(草)剖面和防风固沙林地剖面SIC含量存在显著性差异(P0.05).矮化枣树、未矮化枣树、柠条林、退化人工草地、樟子松林和荒草地土壤剖面无机碳密度分别是有机碳密度的6.19、7.71、10.80、10.78、5.91和1.03倍.综上可见,不同土地利用方式之间土壤碳储量存在明显差异,无机碳的含量远高于有机碳.  相似文献   
29.
Climate change adaptation in the low laying developing countries is becoming crucial at the present time. However, the local knowledge regarding climate change adaptation is not well focused. This study evaluates climate related perception and identifying various adaptation strategies in the low lying areas of North-Eastern Bangladesh. Six focus group discussions and 120 households?? survey were carried out to identify the major climate events in our study areas which were temperature change, drought, heavy rainfall and cyclone and storm surges. Furthermore, main livelihood problems arising from these events were lack of fish availability, scarcity of water in drought seasons and frequent flood in the rainy seasons. Results also revealed that a little portion (10%) of the respondents had well knowledge about the present climate change. However, seasonal livelihood and hazard calendar demonstrated that local people were increasingly changing their livelihood status with changing climatic hazards. At that situation local people tried to adapt themselves with the changing climate through changing their own behavior and introducing some adaptation strategies. We recognized total 16 adaptive measures in the study areas within which crop diversification, floating garden, duck rearing, cage aquaculture, wave protection walls, re-digging of canal and construction of embankments were popular. The present study revealed that local experiences in the face of climate change adaptation have merits which need special consideration. Continuous research and more incentives required for proper documentation and relegate the local adaptation knowledge in the tropic.  相似文献   
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