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1.
The hallmark of development in the Yangtze River Delta (YRD) of East China has been sprawling urbanization. However, air pollution is a significant problem in these urban areas. In this paper, we investigated and analyzed the air pollution index (API) in four cities (Shanghai, Nanjing, Hangzhou and Ningbo) in the YRD from 2001 to 2012. We attempted to empirically examine the relationship between meteorological factors and air quality in the urban areas of the YRD. According to the monitoring data, the API in Shanghai, Nanjing, Hangzhou slightly declined and that in Ningbo increased over the study period. We analyzed the inter-annual, seasonal, and monthly variations of API, from which we found that the air quality had different temporal changes in the four cities. It was indicated that air quality was poor in winter and spring and best in summer. Furthermore, different weather conditions affected air quality level. The wind direction was considered as an important and influential factor to air pollution, which has an impact on the accumulating or cleaning processes of pollutants. The air quality was influenced by the different wind directions that varied with seasons and cities.  相似文献   

2.
Defining the spatial extent of mountain areas has long been a challenge. In the present century, the availability of digital elevation models(DEMs) incorporated into geographic information systems(GIS) has allowed the definition of mountain areas based on topographic and other criteria. This paper presents the various delineations of mountains that have been prepared at three scales – global, regional(Europe), and national – and explores the reasons and processes leading to these delineations, and how they have been used. A detailed case study is then presented for Norway. Overall, two types of approaches to mapping mountains have been taken: first, considering mountains per se, based on elevation and/or topography; second, considering them among other categories, e.g., landforms or biogeographical, environmental or landscape zones. All attempts to map mountain areas derive essentially from the objectives of those commissioning and/or undertaking the work; a unitary definition remains unlikely.  相似文献   

3.
Sustainable tourism,as an integral part of sustainable development,emerged as a logical outcome of preventing the uncontrolled and excessive use of tourism resources and attractions.This study analyzes whether mountain tourism development in Serbia can be sustainable and feasible in the long term.Given the heterogeneity of mountains in Serbia in terms of tourism development,the subject of this research is the achieved level of sustainable tourism development in mountains in the most developed and most visited region in Serbia-sumadija and Western Serbia:Zlatibor,Kopaonik,Tara,Zlatar,Mokra Gora and Go?.The sustainable tourism development level was analyzed by using five groups of the EU’s comparative indicators:economic,social,cultural,environmental and tourist satisfaction indicators.The results showed that the development of tourism in the examined mountains is not fully aligned with sustainable development.The tourist satisfaction indicator has the most acceptable values,which is a good basis for further harmonization of tourism development on the principles of sustainability.Economic indicators,especially the ratio of overnight stays and accommodation capacities,show the most unacceptable values,which indicate the need for implementing changes in the process of tourism development in the coming period.The analysis of sustainable tourism in mountain areas in sumadija and the Western Serbia undoubtfully points out that it is necessary to significantly change the current tourism product portfolio,which implies harmonizing mountain tourism development with global trends.Certainly,a comparative analysis that looks at the degree of sustainability of mountain tourism in some countries of the Alpine region,such as Switzerland,Austria and Slovenia,contributes to this.The more intensive development of tourism throughout the year would significantly improve indicators of sustainable tourism in all analyzed mountain areas of Sumadija and Western Serbia.This would improve the value of economic indicators,which are marked as the most unsustainable.The development of tourism in the summer season,especially recreational and adventure tourism,would improve the social and cultural component of sustainable tourism.Environmental dimension of sustainable tourism would be enhanced by the development of ecotourism.By connecting spatially close mountains(Zlatibor,Zlatar,Tara and Mokra Gora)into a unique and integrated tourism destination,synergistic effects would be achieved resulting in international recognition and making the region of?umadija and Western Serbia competitive on the European market.  相似文献   

4.
China is a mountainous country,and Southwest mountain areas cover the most mountain areas in China and have the most serious problems.Taking Zhaotong city as the study area,based on 902 rural household questionnaires of 11 villages in 2 counties and Tobit model,this paper analyzes the geographical differences and influencing factors of energy consumption for non-production purposes of rural households living in different terrain conditions.This research finds that:(1) Coal takes up the main part of energy consumption in valley areas and coal consumption is mainly affected by per capita cultivated land area,household income,proportion of rural household energy expenditure in total expenditure,coal price,and family population size.Firewood takes up the main part of energy consumption in high mountain areas and firewood consumption is mainly affected by per capita firewood forest area,distance to purchase coal,household income,electricity price,and coal price.(2) Only when the distance is greater than 20 kilometers,that is the average distance of rural households living in middle mountain areas(1,600m~1,800m) to purchase coal,the transportation condition has a significant impact on coal consumption.(3) In high mountain areas,prices of coal and electricity are the main factors influencing energy consumption choice of rural households.Too high prices of coal and electricity would to some extent lead rural households to choose firewood as the main energy consumption type.Compared to coal,rural households prefer to choose electricity.  相似文献   

5.
The increasing impact of disasters at local,national,regional and global scales in recent decades has provided enough evidence to urgently direct attention towards the necessity of disaster risk reduction and management,and this requires knowledge.Knowledge without communication is barren,and to communicate the risk of disaster it is necessary to understand the perception of the people at risk.In particular,this paper deals with the necessity to delineate strategies of risk communication in pursuance of risk knowledge as a core of disaster risk reduction and management,especially in mountain areas of developing countries.To portray this issue,an analysis of landslide risk perception in terms of experience,landslide risk awareness,exposure,preparedness,and risk communication and trust was undertaken in the municipality of Teziutlán,Puebla,Mexico,an area that has been affected for several decades by episodes of mass movement.Analysis of the responses to a risk perception questionnaire has offered valuable insights in terms of the information and knowledge most required by the people living in the area of interest,in order to devise a realistic and functional strategy to communicate the risk of a landslide disaster.This includes better understanding of controlling factorsand drivers of this risk,and the establishment of potential trusted sources of risk communication.Beyond considering practical matters of risk assessment and management,risk perception and communication can increase the resilience of vulnerable people,and can enhance capacity building for present and future generations.  相似文献   

6.
Methods and techniques for the identification, monitoring and management of natural hazards in high mountain areas are enumerated and described. A case study from the western Himalayan Kullu District in Himachal Pradesh, India is used to illustrate some of the methods. Research on the general topic has been conducted over three decades and that in the Kullu District has been carried out since 1994. Early methods of hazards identification in high mountain areas involved intensive and lengthy fieldwork and mapping with primary reliance on interpretation of landforms, sediments and vegetation thought to be indicative of slope fail ures, rock falls, debris flows, floods and accelerated soil surface erosion. Augmented by the use of airphotos and ad hoc observations of specific events over time, these methods resulted in the gradual accumulation of information on hazardous sites and the beginnings of a chronology of occurrences in an area. The use of historical methods applied to written and photographic material, often held in archives and libraries, further improved the resolution of hazards information. In the past two decades, both the need for, and the ability to, accurately identify potential hazards have increased. The need for accurate information and monitoring comes about as a result of rapid growth in population, settlements, transportation infrastructure and intensified land uses and, therefore, risk and vulnerability in mountain areas. Ability has improved as the traditional methods of gathering and manipulating data have been supplemented by the use of remotesensing, automated terrain modeling, global positioning systems and geographical information systems. This paper focuses on the development and application of the latter methods and techniques to characterize and monitor hazards in high mountain areas.  相似文献   

7.
In the summer of 2010/2011 Chile suffered the third most severe energy and water supply crisis in only one decade.This may be surprising as the Andes which accompany the country along 4,200 km are a water tower and could provide more electricity and water than needed.On top of that,it has to be mentioned that Chile also counts with sunny and windy climates and with excellent geothermal energy resources and thus has a huge potential as far as renewable energies are concerned.After analyzing the existing natural conditions,the infrastructure and the present challenges of climate change,it has to be asked in which way Chile can make use of this potential in the near future,considering the legal and political situation and the technological opportunities.It seems that the resources are still hidden in the Andes,and only the key is missing to realize the country’s natural potential.This research has been based on the analysis of existing literature,media,quantitative data from government institutions and other antecedents obtained by the authors in field work done in the South of Chile in 2010.The added value of this compilation lies in the comprehensive perspective,linking the knowledge of climatologists,hydrologists,mountain researchers and energy experts in order to support a sustainable energy and water supply for the future in Chile.From this present research,it can be concluded that Chile necessarilyhas to adopt new energy-related strategies,particularly those aimed at diminishing the strong dependence on traditional sources of energy and establishing new techniques and technologies for generating electricity and utilizing the vast potential that the country is ready to offer,such as that provided by the Andes along 4,200 kilometers.  相似文献   

8.
利用华北地区GPS连续运行基准站网络2008-08~2013-04观测数据,分析36个基准站坐标时间序列的噪声特征。利用区域堆栈滤波方法对GPS单日解坐标时间序列进行共性误差剔除,使用极大似然估计准则定量估计坐标时间序列的噪声特性,并分析有色噪声对测站计算速度的影响。结果表明,华北地区GPS基准站坐标时间序列的共性误差在N、E和U方向分别约为1 mm、1 mm和3 mm,且共性误差具有类似闪烁噪声的特性;共性误差剔除前,坐标时间序列的噪声特性可以用可变白噪声加闪烁噪声模型或可变白噪声加幂律噪声模型来描述;共性误差剔除后降低了坐标时间序列噪声中闪烁噪声的成分,突出了本地效应部分噪声,坐标时间序列的噪声特性可以用可变白噪声加闪烁噪声和随机漫步噪声模型或可变白噪声加幂律噪声模型来描述;最优噪声模型计算的速度误差比仅考虑可变白噪声所计算的速度误差增大5~8倍;剔除共性误差,可使测站速度的精度获得40%左右的提高。  相似文献   

9.
砷污染生态效应及水土体系中砷的治理对策研究   总被引:18,自引:3,他引:18  
针对土壤砷污染严重的环境问题,通过分析砷的环境分布及砷化合物的主要环境性质,探讨了砷的土壤环境容量、土壤中的行为及砷对作物生态效应等问题,进一步研究了土壤砷的来源和存在形态、土壤中砷污染对农作物生长发育的影响及在作物体内的累积规律,提出了严禁随意排放、控制含砷农药使用量以及施加石灰固定土壤中砷的防治措施。  相似文献   

10.
As disasters cripple the world’s prospects for sustainable development, protecting the most vulnerable groups exposed to hazards is one of the main challenges facing humanity. Owing to the systemic nature of risk and the interactions and interdependencies between upland and lowland systems, healthy and productive mountain households and livelihoods are essential to global sustainability. This paper argues that, building on existing international frameworks, and integrated knowledge and praxis, t...  相似文献   

11.
Suffering from fragile environment, poor accessibility and infrastructure, as well as social, political and economic marginality, the interprovincial mountain geographical entities are difficult areas for the regional governance in China. By analyzing the spatial patterns and the influencing factors of the interprovincial mountain geographical names (IMGNs), the goal of this research is to clarify the geographical features of IMGNs and offer alternatives for the management of interprovincial mountain regions in China. The spatial visualization, the analysis of spatial agglomeration and the influencing factors of IMGNs were all implemented under a geographical information system. Results showed that there were 6869 IMGNs in China according to the database of “China’s Second National Survey of Geographical Names (2014–2018)”, including 4209 mountain geographical names, 1684 mountain peak geographical names and 976 the other mountain geographical names. Hunan Province had the largest number of names while Shanghai had the smallest number of names. In addition, the spatial variance of the mountain peak names and the mountain names were larger than that of the other mountain geographical names, and the IMGNs showed a significant clustering phenomenon in the southern part of China. The relative elevation and the population had an impact on the distribution of the IMGNs. The largest number of the names occurred where the relative elevation was between 1000–2000 m and where the population was between 40–50 million. Density of unnamed interprovincial mountain geographical entities declined from west to east in China. The analysis of generic names of different types of IMGNs implied that the naming of IMGNs is inconsistent. Based on these analyses, it is suggested that the government should take the IMGNs as management units, strengthen the naming of unnamed interprovincial mountain geographical entities, standardize the generic names of IMGNs and identify areas of poverty based on the survey of IMGNs.  相似文献   

12.
WATER POLLUTION IN CHINA:CURRENT STATUS, FUTURE TRENDS AND COUNTERMEASURES   总被引:2,自引:0,他引:2  
Based on the statistical data related to water pollution in recent years, this paper firstly describes in detail the current status of water pollution and water quality in rivers, lakes, reservoirs, groundwater and coastal waters in China, then makes a comprehensive analysis on future trends of water pollution in China. The authors hold that the economic power, technology level and management level have determinative influences on the current status and future trends of water pollution. At last, this paper discusses briefly the policies and measures for preventing and controlling water pollution in the light of the national conditions.  相似文献   

13.
The authors discovered large differences in the characteristics of overflows by the calculation of 1) intercepting volume of overflows for sewer systems using SWMM model which takes into consideration the runoff and pollutants from rainfalls and 2) the intercepted volume in the total flow at an investigation site. The intercepting rate at the investigation point of CSOs showed higher values than the SSDs. Based on the modeling of the receiving water quality after calculating the intercepting amount of overflows by considering the characteristics of outflows for a proper management of the overflow of sewer systems with rainfalls, it is clear that the BOD decreased by 82.9%-94.0% for the discharge after intercepting a specific amount of flows compared to the discharge from unprocessed overflows.  相似文献   

14.
1 IN T R O D U C T IO NM ostofthepastw aterm anagem enthasfocused on pointsource pollution,w ith less attention to nonpointsourcepollution.A fterpointsourcesofpollution have been al-ready heavily controlled, nonpoint source pollution(N PSP) has becom e th…  相似文献   

15.
Ecosystem services can be enhanced through ecological restoration,industrial structure adjustment,land-use optimization,and agricultural and forestry ecosystem ...  相似文献   

16.
Deqing County of Guangdong Province is located in the tropic and subtropic mountain areas of China. Its area of cultivated land from landuse survey is 40% larger than the statistical data. Of all cultivated land, owing to flood, waterlogging, drought and barren soil, the high yield land occupies only 30% and the mid-low yield land 70%, which is far more than the percent by statistics. Because the statistic area of cultivated land is less than the actual, the per unit area yield by statistics is higher than the actual. These situations generally exist in the tropic and subtropic mountain area of South China. So the measures to protect the high yield cultivated land strictly, to improve parts of the mid-low yield selectively, to adjust agricultural structure further, and to control soil erosion, are necessary to make best use of its advantages and bypass the disadvantages.  相似文献   

17.
To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy,four Terras AR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County,Sichuan Province,China,was selected as the experimental area.StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM,respectively,and the corresponding radar echo intensity map was calculated.Then,while comparing the radar echo intensity corresponding to the same point position,DEM fusion was carried out,and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data.Finally,a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained.The DEM accuracy was improved on all slopes,and the mean absolute deviation(MAD)improved to 4.798 m,the standard deviation(SD)improved to 6.087 m and the LE90 improved to 40.48 m.The experimental results indicate that the fusion method of highresolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability,which can provide technical support for obtaining highquality terrain information in similar areas.  相似文献   

18.
Novel technologies have been necessary for improving fruit quality and productivity of citrus,labor-saving and orchard conservation on steep slope lands since aging of growers and decrease in the number of successors is remarkable in mountain areas of southwestern Japan. The purpose of this paper is to introduce new technologies for improving citrus production that have been developed in recent years. A new fruit quality control system using drip irrigation and liquid fertilization technique combined with year-round plastic mulching was developed, and it enables high quality and stable citrus fruit production. Water and/or nutrient solution is automatically supplied through drip tubes that are laid under the mulching sheets to give adequate water stress, so as to improve sugar and acid content of fruit. A new transportation system for steep sloping citrus orchards, which is a combination of the monorail system and contour narrow paths, was suggested. A small walking cultivator was developed to explain the procedure of narrow path excavation. After introducing the narrow path, working hours for fertilizer and chemicalherbicide application were reduced. Disasterpr evention mapping of citrus orchards on slope landswas developed based on computer-aided seepage estimation and topographic data. The mapping can show zones of both ascending flow and descendingflow of underground water during heavy rains incitrus orchards. The mapping is considered to be effective for the management of orchards andprevention of erosion on slope lands.  相似文献   

19.
Deqing County of Guangdong Province is located in the tropic and subtropic mountain areas of China. Its area of cultivated land from landuse survey is 40% larger than the statistical data. Of all cultivated land, owing to flood, waterlogging, drought and barren soil, the high yield land occupies only 30% and the mid-low yield land 70%, which is far more than the percent by statistics. Because the statistic area of cultivated land is less than the actual, the per unit area yield by statistics is higher than the actual. These situations generally exist in the tropic and subtropic mountain area of South China. So the measures to protect the high yield cultivated land strictly, to improve parts of the mid-low yield selectively, to adjust agricultural structure further, and to control soil erosion, are necessary to make best use of its advantages and bypass the disadvantages.  相似文献   

20.
Hydrological service is a hot issue in the current researches of ecosystem service, particularly in the upper reaches of mountain rivers in dry land areas, where the Qilian Mountain is a representative one. The Qilian Mountain, where forest, shrubland and grassland consist of its main ecosystems, can provide fresh water and many other ecosystem services, through a series of eco-hydrological process such as precipitation interception, soil water storage, and fresh water provision. Thus, monitoring water regulation and assessing the hydrological service of the Qilian Mountain are meaningful and helpful for the healthy development of the lower reaches of arid and semi-arid areas. In recent 10 years, hydrological services have been widely researched in terms of scale and landscape pattern, including water conservation, hydrological responses to afforestation and their ecological effects. This study, after analyzing lots of current models and applications of geographical information system (GIS) in hydrological services, gave a scientific and reasonable evaluation of mountain ecosystem in eco-hydrological services, by employing the combination of international forefronts and contentious issues into the Qilian Mountain. Assessments of hydrological services at regional or larger scales are limited compared with studies within watershed scale in the Qilian Mountain. In our evaluation results of forest ecosystems, it is concluded that long-term observation and dynamic monitoring of different types of ecosystem are indispensable, and the hydrological services and the potential variation in water supplement on regional and large scales should be central issues in the future research.  相似文献   

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