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101.
The aim of this research is to determine agricultural land loss and environmental pollution caused by industrialization and urban sprawl using the Geographical Information System (GIS) and Remote Sensing technique (RS). Remotely sensed data is the most powerful tool for monitoring land use changes and GIS is the best way to store and reproduce various kinds of integrated data. Considering the rapid increase of population the loss of fertile agricultural soils is a very dangerous situation for the future of the country. Thus, people are living in the cities in (with adverse) conditions of insufficient drinking water, infrastructure problems, inadequate landscape and many unsolved (extreme) environmental problems. During the last 36 years, unplanned urbanization and industrialization have led to the use of agricultural areas for non-agricultural purposes in the Torbali (Izmir) region, which has the most fertile soils of the Aegean Region. Within this study, a database was created on the parameters of land loss and environmental pollution by means of field observation, interpretation of satellite images (ASTER), aerial photos(1/25.000 scale), topographic map ,soil map, and 1/5.000 scale cadastral map. Results of previous researches and the archives of Torbali municipality were used as ancillary data. In the research, urbanization and industrialization of the town was studied by (using) GIS and RS between 1965 and 2001. Since 1965, 4.742.357 m2 agricultural land, mostly of first and second land use capability classes, has been lost due to unplanned urban and industrial developments. Urbanization and industrialization involved an area of which 58% was being used as irrigated lands, 25 % rain feed (rain fed lands)and 17 % for olive growing.  相似文献   
102.
Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated roofing industry and experienced installers for future green roof construction.  相似文献   
103.
Jiang Y  Chen Y  Younos T  Huang H  He J 《Ambio》2010,39(7):467-475
Since China has the largest population in the world, the available water resources per capita in China are very limited. With the rapid economic development that is currently occurring, the shortage of water resources at the national level has become extremely critical. How to solve the problems due to water scarcity and water pollution has received increasing attention from the Chinese government and various communities. In order to provide a sustainable development environment for 1.6 billion people in the future, the whole country has started to reform urban water resources management systems in terms of related policies, regulations, methodologies, and technologies focusing on improving the efficiency and effectiveness in water use. Urban water quota management has now become a core strategy in developing a water resources governance model for water demand management aiming at establishing a water-saving society. This paper introduces the main stages and the processes of implementing water quota management in China, analyzes the basic principles, and expounds the elements, information foundation, core module and operational model of the urban water quota management system. It has been demonstrated that urban water quota management has made some remarkable contribution not only in transforming the pattern of water mode and strengthening water management enforcement but also in integrating various management methods in saving water and preventing pollution.  相似文献   
104.
An index based method is developed that ranks the subwatersheds of a watershed based on their relative impacts on watershed response to anticipated land developments, and then applied to an urbanizing watershed in Eastern Pennsylvania. Simulations with a semi-distributed hydrologic model show that computed low- and high-flow frequencies at the main outlet increase significantly with the projected landscape changes in the watershed. The developed index is utilized to prioritize areas in the urbanizing watershed based on their contributions to alterations in the magnitude of selected flow characteristics at two spatial resolutions. The low-flow measure, 7Q10, rankings are shown to mimic the spatial trend of groundwater recharge rates, whereas average annual maximum daily flow, , and average monthly median of daily flows, , rankings are influenced by both recharge and proximity to watershed outlet. Results indicate that, especially with the higher resolution, areas having quicker responses are not necessarily the more critical areas for high-flow scenarios. Subwatershed rankings are shown to vary slightly with the location of water quality/quantity criteria enforcement. It is also found that rankings of subwatersheds upstream from the site of interest, which could be the main outlet or any interior point in the watershed, may be influenced by the time scale of the hydrologic processes.  相似文献   
105.
Cultural ecosystem services are a function of people and place, so may change as a location transitions from rural to urban. Singapore has undergone rapid urbanization after its independence in 1965, with a concomitant decline in natural habitat extent and accessibility. Using coastal mangrove forests as a case study habitat, changing cultural values were explored with a novel array of techniques, including qualitative archival analysis (photographs, oral histories), current sources (publically uploaded social media photographs), and surveys of (a) the general public and (b) visitors to publically accessible mangroves. Cultural value changed through time, with a significant transition from intrinsic, intrapersonal values (spiritual, cultural heritage) to instrumental, interpersonal values (recreation, education). Additionally, cultural value varied between different mangroves depending on their public accessibility, and the evolving degree of human interaction with the ecosystem as urban development occured. Cultural values change as development transitions, though mangroves still play an important cultural role in a heavily urbanized environment.  相似文献   
106.
通过西部11省、市、自治区1997~2012年面板数据,对西部地区城镇化、贸易开放、经济增长、能源消费与碳排放之间的动态关系进行了研究。使用3种面板单位根检验方法,结果显示:所有变量都是一阶单整;Pedroni和Kao协整检验表明变量之间存在协整关系;通过FMOLS估计方法进行回归,结果发现经济增长、能源消费、贸易开放都对CO2排放产生正的影响;西部地区GDP平方与CO2的关系符合环境库兹涅茨曲线特征;城镇化对CO2产生负的影响。格兰杰因果关系检验显示,短期内,GDP、贸易开放是CO2的单向格兰杰原因;能源消费、城镇化是CO2的双向格兰杰原因;能源消费、贸易开放是GDP的双向格兰杰原因;贸易开放是能源消费的双向格兰杰原因。存在误差修正机制,当系统在短期内偏离长期均衡时,5个变量在调整过程中能发挥重要作用,使其重新回到均衡状态。最后,提出政策建议。  相似文献   
107.
This paper analyzes characteristics, major driving forces and alternative management measures of land-use change in Kunshan, Jiangsu province, China. The study used remote sensing (RS) maps and socio-economic data. Based on RS-derived maps, two change matrices were constructed for detecting land-use change between 1987 and 1994, and between 1994 and 2000 through pixel-to-pixel comparisons. The outcomes indicated that paddy fields, dryland, and forested land moderately decreased by 8.2%, 29% and 2.6% from 1987 to 1994, and by 4.1%, 7.6% and 8% from 1994 to 2000, respectively. In contrast, the following increased greatly from 1987 to 1994: artificial ponds by 48%, urban settlements by 87.6%, rural settlements by 41.1%, and construction land by 511.8%. From 1994 to 2000, these land covers increased by 3.6%, 28.1%, 23.4% and 47.1%, respectively. For the whole area, fragmentation of land cover was very significant. In addition, socio-economic data were used to analyze major driving forces triggering land-use change through bivariate analysis. The results indicated that industrialization, urbanization, population growth, and China's economic reform measures are four major driving forces contributing to land-use change in Kunshan. Finally, we introduced some possible management measures such as urban growth boundary (UGB) and incentive-based policies. We pointed out that, given the rapidity of the observed changes, it is critical that additional studies be undertaken to evaluate these suggested policies, focusing on what their effects might be in this region, and how these might be implemented.  相似文献   
108.
Urbanization is one of the most important aspects of global change. The process of urbanization has a significant impact on the terrestrial ecosystem carbon cycle. The Yangtze Delta region has one of the highest rates of urbanization in China. In this study, carried out in Jiangyin County as a representative region within the Yangtze Delta, land use and land cover changes were estimated using Landsat TM and ETM+ imagery. With these satellite data and the BEPS process model (Boreal Ecosystem Productivity Simulator), the impacts of urbanization on regional net primary productivity (NPP) and annual net primary production were assessed for 1991 and 2002. Landsat-based land cover maps in 1991 and 2002 showed that urban development encroached large areas of cropland and forest. Expansion of residential areas and reduction of vegetated areas were the major forms of land transformation in Jiangyin County during this period. Mean NPP of the total area decreased from 818 to 699 gCm(-2)yr(-1) during the period of 1991 to 2002. NPP of cropland was only reduced by 2.7% while forest NPP was reduced by 9.3%. Regional annual primary production decreased from 808 GgC in 1991 to 691 GgC in 2002, a reduction of 14.5%. Land cover changes reduced regional NPP directly, and the increasing intensity and frequency of human-induced disturbance in the urbanized areas could be the main reason for the decrease in forest NPP.  相似文献   
109.
深圳市的城市化及城市洪涝灾害   总被引:7,自引:3,他引:7  
城市洪涝灾害是我国自然灾害中影响最严重的灾害之一,城市化作为我国经济发展的结果,使城市洪涝灾害损失日趋严重。本文针对我国城市化发展现状及趋势,在已有城市洪涝灾害研究成果的基础上,将城市水文学的概念应用于水力学模型之中,通过对深圳市洪涝灾害的数值模拟,初步探明了城市化对洪涝灾害的影响。  相似文献   
110.
城市化与现代社会中的水害演变:从日本经历看今日深圳   总被引:11,自引:4,他引:11  
我国沿海经济开发区正进入城市化的活跃发展时期。发达国家的经历表明,城市化必将导致水灾害模式的变化,引出城市水灾损失持续上升的严重问题。日本从60年代中期开始研究城市型水灾害问题,随后其治水事业从方针、政策到对策均作了重大的调整,为社会经济的持续稳定发展创造了良好的条件。深圳市1993年两次暴雨洪涝成灾,损失惨重,其水情灾情均受到了该区域城市化的显著影响,说明我国城市型水灾害的研究亟待加强。本文从治水的角度将日本的城市化现象及其引起的水灾害特征变化与深圳市的实际情况进行了比较并得出若干有益的结论。  相似文献   
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