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911.
Shaohong Wu Jikun Huang Yanhua Liu Jiangbo Gao Jun Yang Wentao Wang Yunhe Yin Hao Luan Wanlu Dong 《中国人口.资源与环境(英文版)》2014,(2)
Climate change strongly affected the structure and functions of natural ecosystems,e.g.the vegetation productivity decreased in the Northeast permafrost region due to the higher temperature and less precipitation,whereas in the Tibetan Plateau,the vegetation productivity increased,owing to the improved thermal resource.Climate change led to reduced precipitation in North and Northeast China and thus the reduced surface runoff.The public needs for energy were changed because of climate change,e.g.the shorter heating period in winter.Climate change profoundly influenced human health,pathophoresis and major projects by increasing extreme events,including frequency and magnitude,and causing more serious water shortage.Under the background of climate change,although the improved thermal resources can be helpful for extending the crop growth period,more extreme events may resulted in more instability in agricultural productivity.Not only did climate change indirectly affect the secondary and tertiary industries through the impacts on agriculture and natural resources,but also climate change mitigation measures,such as carbon tax,tariff and trading,had extensive and profound influences on the socioeconomic system.Further analysis indicated that the impact of climate change presented significant regional differences.The impact had its pros and cons,while the advantages outweighed the disadvantages.Based on the above analysis on the impacts of climate change,we put forward suggestions on coping with climate change.First,scientifically dealing with climate change will need to seek advantages while avoiding the disadvantages of climate change in order to achieve the orderly adaptation to climate change,which is characterized with"Overall best,long-term benefit."Second,quantitative adaptation should be given more attention,e.g.proposing operational schemes and predictable goals and using uncertainty analysis on adaptation measures.Third,more active coping strategy should be adopted to enhance China's future comprehensive competitiveness.The strategies include but are not limited to gradually adjusting the industrial structure,intensifying the research and development(RD)of emission reduction technology and actively responding to the influence of carbon tax,tariff and trading on socioeconomic development in China. 相似文献
912.
2009年3月~2010年4月采用干漏斗法和手捡法对南京方山生态公园针阔混交林、茶园、农田等3种典型人工植被生境的土壤动物群落结构及其季节变化进行初步调查。共采得土壤动物样本3 164个,27个类群隶属于5门12纲23目。结果表明:近孔寡毛目(Plesiopora)、弹尾纲(Collembola)和蜱螨目(Acarina)为常年优势类群;双翅目(Diptera)、同翅目(Homoptera)、膜翅目(Hymenoptera)、等足目(Isopoda)、后孔寡毛目(Opisthopora)和鞘翅目(Coleoptera)则为常年常见类群。土壤动物群落类群数和个体数量的季节消长规律分别是夏季>冬季>秋季>春季和夏季>秋季>冬季>春季。不同植被生境的土壤动物个体数量总数依次为茶园>混交林>农田;不同季节、不同人工植被类型以及不同季节和不同人工植被类型之间土壤动物群落的组成具有较大变化,不同类群之间个体数量差异显著。多样性分析表明,土壤动物类群多样性和均匀性指数在夏季时最高;茶园和混交林多样性指数和丰富度指数均高于农田。不同植被类型土壤动物垂直分布特征均表现为具有明显的表聚性,土壤动物的类群垂直分布差异明显,类群数随土层向下逐步减少 相似文献
913.
Yuqiang Liu Ruidong Peng Ya Xu Changxin Nai Lu Dong Junrong Ren 《Journal of Material Cycles and Waste Management》2014,16(4):597-607
The stability of hazardous waste (HW) landfill is a major security risk to the landfill environmental safety. The mechanical behavior of waste controls many aspects of landfill design and operation, including stability and settlement issues and the integrity of geosynthetic and liner components. This study presents the results of a laboratory experiment to learn the mechanical properties of HW collected from the Hangzhou HW landfill. Measured mechanical behavior was compared with results for municipal solid waste (MSW) to assess their discrepancies. The particle size of HW was analyzed by the sieving and hydrometer methods. Because HW comes primarily from industrial plants in the form of sludge or slag, their particle sizes are generally smaller than those of MSW. This study indicates that the shear strength parameters of HW are more sensitive to the methods of testing and calculation than those of MSW. Numerical simulations demonstrate that the safety factor of a landfill is affected by the mechanical properties of HW, especially cohesion and friction angle. Because of the lower particle size and wider compression ratio, compared to MSW, an HW landfill should be taken more care in its operational procedures so as to increase its stability. 相似文献
914.
Zhe Liu Yong Geng Pan Zhang Huijuan Dong Zuoxi Liu 《Environmental science and pollution research international》2014,21(17):10243-10253
In China, local governments of many areas prefer to give priority to the development of heavy industrial clusters in pursuit of high value of gross domestic production (GDP) growth to get political achievements, which usually results in higher costs from ecological degradation and environmental pollution. Therefore, effective methods and reasonable evaluation system are urgently needed to evaluate the overall efficiency of industrial clusters. Emergy methods links economic and ecological systems together, which can evaluate the contribution of ecological products and services as well as the load placed on environmental systems. This method has been successfully applied in many case studies of ecosystem but seldom in industrial clusters. This study applied the methodology of emergy analysis to perform the efficiency of industrial clusters through a series of emergy-based indices as well as the proposed indicators. A case study of Shenyang Economic Technological Development Area (SETDA) was investigated to show the emergy method’s practical potential to evaluate industrial clusters to inform environmental policy making. The results of our study showed that the industrial cluster of electric equipment and electronic manufacturing produced the most economic value and had the highest efficiency of energy utilization among the four industrial clusters. However, the sustainability index of the industrial cluster of food and beverage processing was better than the other industrial clusters. 相似文献
915.
上海市典型城市河岸带不同植被类型下土壤反硝化作用研究 总被引:2,自引:0,他引:2
为了解城市河岸带不同植被类型下土壤的反硝化速率及其影响因子,在上海市城市河岸带的长风绿地选择了熊掌木、硕苞蔷薇和矮生百慕大草3种植被类型,于2012年3月(春初)、5月(春季)、7月(夏季)、11月(秋季)测定了其下不同深度(2~5 cm、12~15 cm、22~25 cm和32~35 cm)土壤的反硝化速率和土壤的粒度、含水率、SOC、NH4+和NO3-含量等基本理化性质。结果表明:长风绿地3种植被类型下土壤理化性质和反硝化速率具有一定的差异性,但均表现为2~5 cm深度土壤反硝化速率显著高于其他深度;熊掌木和硕苞蔷薇2~5 cm深度土壤反硝化速率均为春初显著高于其他季节,而草地2~5 cm深度反硝化速率在春夏季显著高于春初和秋季;其他深度土壤均不存在显著的季节性差异;植被类型、深度和季节对反硝化速率的单一和综合影响效应(除植被类型*深度外)均显著;反硝化速率与土壤的SOC、NH4+和NO3-含量呈极显著正相关(p<001),而与土壤含水率和气温没有显著相关关系 相似文献
916.
Nutrient and dissolved inorganic carbon are two important factors that influence the development and species composition of submerged macrophyte communities in shallow lake ecosystems. Yet little is known about their potential interactive effects on the submerged macrophytes and competition outcome of macrophyte–phytoplankton. We performed a mesocosm experiment to investigate the growth and photosynthetic performance of three submerged macrophytes in relation to phytoplankton/epiphyton with nutrient and bicarbonate enrichment. During the experimental period (42 d), increase in nutrient loading in water column resulted in a substantial burst of phytoplankton and epiphyton growth and increased light attenuation. When combined with nutrient loading, bicarbonate enrichment also resulted in a heavily phytoplankton- and epiphyton-dominated state, although bicarbonate enrichment per se does not cause the phytoplankton and epiphyton growth. However, increase in nutrient loading in water column had significant negative impact on individual performances (growth and photosynthesis) of the three submerged macrophytes and bicarbonate enrichment increased the effect of eutrophication on two dissected-leaf macrophytes (M. spicatum and E. nuttallii). Furthermore, our results also suggest that species-specific photosynthetic performances occurred when submerged macrophytes in an environment with high abundance of phytoplankton/epiphyton. This study highlighted that increase in nutrient loading and bicarbonate in water column is likely to interactively impact both abiotic and biotic properties of a freshwater ecosystem. The interactions of these two factors could select macrophyte species that are able to resist the shading from phytoplankton/epiphyton, making these species more dominant in natural freshwater ecosystems. 相似文献
917.
目前柴油发电机房噪声的设计与治理方法没有形成固定的模式,为了解决这个问题,文章以某柴油发电机房噪声治理为例,对该噪声控制进行理论探讨、设计计算和技术优化。以此为据完成了工程,取得了良好的处理效果。并为柴油发电机房噪声控制提供了一种可供参考的方法。 相似文献
918.
Numerical Investigation of Boundary-Layer Evolution and Nocturnal Low-Level Jets: Local versus Non-Local PBL Schemes 总被引:3,自引:0,他引:3
Kesu Zhang Huiting Mao Kevin Civerolo Stephen Berman Jia-Yeong Ku S. Trivikrama Rao Bruce Doddridge C. Russell Philbrick Richard Clark 《Environmental Fluid Mechanics》2001,1(2):171-208
Numerical simulations of the evolution of the planetary boundary layer (PBL) and nocturnal low-level jets (LLJ) have been carried out using MM5 (version 3.3) with four-dimensional data assimilation (FDDA) for a high pollution episode in the northeastern United States during July 15–20, 1999. In this paper, we assess the impact of different parameterizations on the PBL evolution with two schemes: the Blackadar PBL, a hybrid local (stable regime) and non-local (convective regime) mixing scheme; and the Gayno–Seaman PBL, a turbulent kinetic energy (TKE)-based eddy diffusion scheme. No FDDA was applied within the PBL to evaluate the ability of the two schemes to reproduce the PBL structure and its temporal variation. The restriction of the application of FDDA to the atmosphere above the PBL or the lowest 8 model levels, whichever is higher, has significantly improved the predicted strength and timing of the LLJ during the night. A systematic analysis of the PBL evolution has been performed for the primary meteorological fields (temperature, specific humidity, horizontal winds) and for the derived parameters such as the PBL height, virtual potential temperature, relative humidity, and cloud cover fraction. There are substantial differences between the PBL structures and evolutions simulated by these two different schemes. The model results were compared with independent observations (that were not used in FDDA) measured by aircraft, RASS and wind profiler, lidar, and tethered balloon platforms during the summer of 1999 as part of the NorthEast Oxidant and Particle Study (NE-OPS). The observations tend to support the non-local mixing mechanism better than the layer-to-layer eddy diffusion in the convective PBL. 相似文献
919.
Jia-Yeong Ku Huiting Mao Kesu Zhang Kevin Civerolo S. Trivikrama Rao C. Russell Philbrick Bruce Doddridge Richard Clark 《Environmental Fluid Mechanics》2001,1(2):209-233
This paper examines the effects of two different planetary boundary-layer (PBL) parameterization schemes – Blackadar and Gayno–Seaman – on the predicted ozone (O3) concentration fields using the MM5 (Version 3.3) meteorological model and the MODELS-3 photochemical model. The meteorological fields obtained from the two boundary-layer schemes have been used to drive the photochemical model to simulate O3 concentrations in the northeastern United States for a three-day O3 episodic period. In addition to large differences in the predicted O3 levels at individual grid cells, the simulated daily maximum 1-h O3 concentrations appear at different regions of the modeling domain in these simulations, due to the differences in the vertical exchange formulations in these two PBL schemes. Using process analysis, we compared the differences between the different simulations in terms of the relative importance of chemical and physical processes to O3 formation and destruction over the diurnal cycle. Finally, examination of the photochemical model's response to reductions in emissions reveals that the choice of equally valid boundary-layer parameterizations can significantly influence the efficacy of emission control strategies. 相似文献
920.