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991.
基于RMP的事件型文化创意旅游产品开发   总被引:1,自引:0,他引:1  
粟娟 《资源开发与市场》2010,26(10):940-943
事件型文化创意旅游产品是当前文化创意旅游产品中最具吸引力的产品,其研发对当前旅游产业的转型与升级具有重要意义。从事件文化创意旅游产品的含义及其特征出发,分析了当前产品开发中资源认识不清、策划缺乏创新等问题,从而提出了RMP总体开发思路,以及正确认识产品资源本质、积极利用"触媒效用"等开发对策,为深度开发事件型文化创意旅游产品提供新的思路。  相似文献   
992.
Simultaneous daily measurements of water-soluble organic nitrogen (WSON), ammonium and nitrate were made between July and November 2008 at a rural location in south-east Scotland, using a ‘Cofer’ nebulizing sampler for the gas phase and collection on an open-face PTFE membrane for the particle phase. Average concentrations of NH3 were 82 ± 17 nmol N m?3 (error is s.d. of triplicate samples), while oxidised N concentrations in the gas phase (from trapping NO2 and HNO3) were smaller, at 2.6 ± 2.2 nmol N m?3, and gas-phase WSON concentrations were 18 ± 11 nmol N m?3. The estimated collection efficiency of the nebulizing samplers for the gas phase was 88 (±8) % for NH3, 37 (±16) % for NO2 and 57 (±7) % for WSON; reported average concentrations have not been corrected for sampling efficiency. Concentrations in the particle phase were smaller, except for nitrate, at 21 ± 9, 10 ± 6 and 8 ± 9 nmol N m?3, respectively. The absence of correlation in either phase between WSON and either (NH3 + NH4+) or NO3? concentrations suggests atmospheric WSON has diverse sources. During wet days, concentrations of gas and particle-phase inorganic N were lower than on dry days, whereas the converse was true for WSON. These data represent the first reports of simultaneous measurements of gas and particle phase water-soluble nitrogen compounds in rural air on a daily basis, and show that WSON occurs in both phases, contributing 20–25% of the total water-soluble nitrogen in air, in good agreement with earlier data on the contribution of WSON to total dissolved N in rainfall in the UK.  相似文献   
993.
耐高温反渗透膜在化工废水处理中的应用   总被引:1,自引:0,他引:1  
以某化工工艺废水的超滤出水为原水,采用耐高温反渗透膜进行处理,考察了操作压力、废水pH、膜面流速及废水总铁质量浓度对耐高温反渗透膜产水通量及脱盐率(以电导率减小率计,下同)和TOC去除率的影响。实验结果表明,在操作压力为0.24 MPa、废水pH为7.60、膜面流速为2.0 m/s的最佳条件下运行4 200 min后,产水通量衰减约73%,反渗透系统的脱盐率为95%~97%,TOC去除率为83%~95%,出水电导率在50μs/cm左右,出水TOC为21~23 mg/L。  相似文献   
994.
重金属污染土壤修复技术综述   总被引:4,自引:0,他引:4  
张海燕  刘阳  李娟  卢海威 《四川环境》2010,29(6):138-141
土壤重金属污染是当前重要的世界性环境问题之一。随着重金属污染土壤场地日渐增多,如何安全有效地修复并利用这些受污染的土壤已成为我国急需解决的环境和社会问题。本文介绍了重金属污染土壤常用修复技术的原理、优缺点,并重点介绍了土壤淋洗修复技术,对目前淋洗剂的应用情况、作用机制进行了评价。  相似文献   
995.
采用SSM数学模型分析方法和变异系数,以入境旅游人数和旅游外汇收入为样本数据,从客源市场结构和旅游竞争力两个方面对比分析了1996—2007年大连、青岛我国北方两个具有代表性的滨海城市入境旅游的区域发展差异。结果表明,从客源市场和相对差异都可发现两个城市入境旅游的区域差异经历了"减小—增大"的演变过程,原因在于青岛便利的交通、独特的文化和区位优势,使青岛由落后效仿者变为领先者,充分发挥了厚积薄发的优势。  相似文献   
996.
Alterations in flow regimes of large rivers may originate or increase risks to ecosystems and humans. The Paraná River basin (South America) undergoes human pressures (e.g., heavy damming in the upper basin, deforestation, and mixed pollution) that may affect the water quantity and quality of its terminal Delta (Argentina). In this study, after applying univariate and multivariate change-point detection and trend analyses to the daily data series of flows incoming to the Delta (Paraná-Santa Fe section), flow characteristics were compared by Indicators of Hydrologic Alteration (IHA) and Environmental Flow Components (EFC). Some flood characteristics were also compared from hydrometric levels in the middle Delta (San Pedro station). Chemical and microbiological water variables in the main rivers of the “Paraná Delta” Biosphere Reserve were examined during two extreme hydrologic years (October 2008 to July 2010) to detect potential risk factors in association with hydrologic conditions. In the Lower Paraná River, a historical period (1903–1972) and two more altered periods (1973–1999 wet period and 2000–2014 dry period) were identified. Flow duration curves evidenced different changes in both altered periods, reflecting the joint effect of climatic variability and human influence. The most evident alterations in the flow regime were the lack of record of the extreme-low-flow component, the attenuation of monthly flow seasonality, and the increase in the number of reversals (dry period) and in the variability of maximum and minimum flow dates. These alterations are consistent with the monthly and daily flow regulation by upstream dams evidenced by available data from the current dry period. In the middle Delta, the marked monthly seasonality in flood days decreased only in the wet period. The proportion between the number of flood days exceeding the evacuation level and that of those exceeding the warning level doubled in the wet period but decreased only slightly in the dry period. In the Delta Reserve rivers, concentrations of Escherichia coli, cadmium, lead, iron, manganese, and ammonium exceeded guideline levels under a severe drought and a dispersal of cyanobacteria appeared under a high-flow pulse in La Niña year. The ammonium concentration exceeded the level for human drink with the overbanking flood stage in El Niño year. These occasional detections pose a potential risk to the aquatic life and, especially, to the inhabitants of the Reserve. Flow duration curves, IHA, and EFC are useful tools to evaluate trends or changes of ecological and social relevance in flow regime characteristics.  相似文献   
997.
Policy-making in social-ecological systems increasingly looks to iterative, evolutionary approaches that can address the inherent complexity of interactions between human wellbeing, provision of goods, and the maintenance of ecosystem services. Here, we show how the analysis of available time-series in tropical delta regions over past decades can provide important insight into the social-ecological system dynamics in deltaic regions. The paper provides an exploratory analysis of the recent changes that have occurred in the major elements of three tropical deltaic social-ecological systems, such as demography, economy, health, climate, food, and water. Time-series data from official statistics, monitoring programmes, and Earth observation data are analysed to explore possible trends, slow and fast variables, and observed drivers of change in the Amazon, Ganges–Brahmaputra–Meghna and Mekong deltas. In the Ganges–Brahmaputra–Meghna delta zone, increasing gross domestic product and per capita income levels since the 1980s mirror rising levels of food and inland fish production. In contrast, non-food ecosystem services, such as water availability, water quality, and land stability appear to be deteriorating. In the Amazon delta, natural and anthropogenic perturbations are continuously degrading key ecosystem services, such as carbon storage in biomass and soils, the regulation of water balance, and the modulation of regional climate patterns. In the Mekong delta, rapid economic development, changing land-use practices, and salinity intrusion are progressively putting more pressure on the delivery of important provisioning services, such as rice and inland aquaculture production, which are key sources of staple food, farm incomes, and export revenue. Observed changes in many key indicators of ecosystem services point to a changing dynamic state and increased probability of systemic threshold transformations in the near future.  相似文献   
998.
In this study the effects of the main marine pollutants (metals, PAHs, PCBs and DDTs) were assessed in native mussels from the Mediterranean coast of Spain. For this purpose several biomarkers such as benzo[a]pyrene hydroxylase (BPH), DT-diaphorase (DTD), glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPs), glutathione reductase (GR), metallothionein (MT) and lipid peroxidation (LPO) were measured in the digestive gland. Results showed increased LPO levels in mussels which accumulated high loads of organic compounds and arsenic in their tissues. BPH levels correlated to the concentrations of organic compounds in mussel tissues, though the range of BPH response was low in relation to the high gradient of accumulation of organic pollutants. Increased BPH levels, concomitant to low DTD and GST activities, were detected in mussels which presented high levels of organic pollutants in their tissues. This suggests that signs of LPO present in these organisms are related to the imbalance between phase I and phase II biotransformation processes. Furthermore, the increased levels of MT and CAT detected in mussels which showed high levels of Cd in their tissues appear to reflect a coordinated response which protects against the toxicity of this metal. The application of these biomarkers in environmental assessment is discussed.  相似文献   
999.
Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOGLIFE is a new long-term 'common-garden' experiment to disentangle the effects of species' wood traits and site-related environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation.  相似文献   
1000.
Adsorption has been used to study the removal of atenolol, caffeine, diclofenac and isoproturon, pharmaceutical compounds as emerging contaminants and an endocrine disruptor from ultrapure water and a municipal wastewater treatment plant effluent with three carbonaceous materials: activated carbon, multiwalled carbon nanotubes and carbon nanofibers. The adsorption capacities were studied in the temperature range of 25-65°C and pH range from 3 to 9. Several model isotherms were used to model the adsorption equilibrium data. Also, the competitive adsorption was evaluated.  相似文献   
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