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  • Invited Paper
    ZHANG Linxiu
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    Internationally, impact evaluation has become an essential part of program design. However, the challenge on impact evaluation is how to attribute, or how to find out the true impact of program intervention. In general there are two broad types of evaluation methods: non-experimental and experimental. The objectives of this paper are: (1) to briefly compare basic characteristics of each and different evaluation methods, and (2) to discuss in more detail the basic principles and major implementation issues of Randomized Controlled Trails (RCTs). Then the paper uses a current evaluation project of baby nutrition intervention carried out by Rural Education Action Program (REAP) to further elaborate how to evaluate the "true" project impacts using RCTs. Methods belong to non-experimental types include simple comparison of before and after treatment, DID, PSM, IV, RDD, etc. RCT as a rigorous impact evaluation method has its key advantage of avoiding selection bias: the issue that could not be easily solved using other methods. There are five key components in designing an RCT, theory based casual chain analysis to determine what type of interventions in order to achieve target impact, the next is to determine intervention unit and also the way and level of randomizing. A careful examination on likelihood of other factors which may have impact on the outcome should be carefully examined so to be built into intervention design. The last but very important work is to determine project size through power calculation. The implementation of an RCT need to go through "three steps": first is baseline survey, then to randomly assign a group of sample as intervention group while the other half as control group. The last step is evaluation survey. Only with both baseline and evaluation data, one can use then to measure the true impact of project intervention. Like any other methods, RCTs also has its implementation challenges, such as spillover effects, cross contamination, non-compliance or attrition. As a cutting-edge impact evaluation method, Randomized Control Trail (RCT) has a great potential to be widely used in rigorous impact evaluation.
  • Global Change
  • Global Change
    FANG Weihua, LIN Wei
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    Quantitative probabilistic typhoon risk model needs a large number of wind samples as input. However, in many areas, historical observation data is inadequate in both spatial and temporal dimensions, which may introduce great bias into risk assessment results. Combined with stochastic track model, parametric wind field model can provide a large number of wind speed samples to quantify wind risk, thanks to its simplicity in computation and solid scientific foundation. According to the general process of typhoon wind modeling, in this paper, firstly the estimation methods of maximum wind speed, radius of maximum wind speed and Holland B parameter for wind field model are reviewed, and the progress in gradient wind field model and boundary layer model is illustrated. Secondly, the theories and applications of wind speed adjustment for surface roughness, terrain, gusts and sea-land transition are analyzed. Thirdly, major software systems with wind field components are also summarized. Finally, it is suggested that the integration of meteorology, wind engineering, oceanic and disaster risk sciences be enhanced. Surface roughness estimation by remote sensing, and terrain adjustment are proposed as priority research areas for China in the future.
  • Global Change
    XU Haojie, YANG Taibao
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    Changes of climate factors in the Qaidam Basin during 1981-2010 were analyzed based on the monthly temperature and precipitation data from meteorological stations. Rate of linear tendency and Mann-Kendall test were used to illustrate the change trends and detect abrupt changes of meteorological elements respectively. In addition, lake area changes and vegetation activity changes in the Qaidam Basin in response to climate changes were discussed using Landsat TM/ETM+ images, NOAA/AVHRR-NDVI and EOS/MODIS-NDVI products. The results showed that (1) The Qaidam Basin experienced an overall rise in temperature, especially in autumn and winter during 1981-2010. Temperature changed abruptly from low to high in 1987 and the increase has become more rapid since 1998. (2) The annual available precipitation showed a "decrease-increase-decrease-increase" change in recent 30 years, but the inter-annual trend of annual available precipitation was similar to annual mean temperature at a rate of 5.65 mm/10a. Available precipitations were low in 1981-1985, 1990-2001, but high in 1985-1990, 2001-2010. An abrupt change to warm-wet happened in the mid-late 1980s. However, an overall trend of warm-dry was detected from the mid-1990s to the end of the 20th century. A significant warm-wet trend of climate has arrived once again since the early 21th century. (3) Variations of lake area and vegetation growth were significantly affected by the change of wet and dry climate. The "expansion-atrophy-expansion" pattern in lake areas correlated with summer available precipitations which happened in 1985-1990, 1990-2001, 2001-2010 respectively. (4) The "degradation-amelioration-degradation-amelioration" pattern in vegetation growth was closely related with growing season available precipitation which happened in 1981-1985, 1985-1990, 1990-2001, 2001-2010.
  • Global Change
    XI Xiumei, LIU Hailong
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    In this paper, we used Morlet wavelet transform method to analyze the relationship between annual runoff in the mainstream of the Tarim River and sunspots activity dring 1957-2011. Results indicated that both annual runoff of the mainstream of Tarim River and number of sunspots were decreased dring 1957-2011. There were main periods of 4 a, 8 a, 18 a, and 21 a in annual runoff. On the scales of 8~9 a and 18~21 a, the annual runoff and number of sunspots had similar primary cycles. Sunspots activity had almost no effect on the characteristics of annual runoff change of the 4 a cycle, but the characteristics of the 18~21 a cycle were mainly influenced by sunspots activity. The annual runoff change of 8 a primary cycle was once closely related to sunspots activity, but the correlation was disrupted after 1980 due to strong interferences of human activities. This paper forecasts that 2012-2020 may be a withered water period for annual runoff in the mainstream of Tarim Riverin, and the average annual runoff may be about 35×108~40×108 m3
  • Global Change
    HAN Cuihua, HAO Zhixin, ZHENG Jingyun
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    Based on daily meteorological dataset of 623 stations during 1951-2010 in China, using the orthogonal rotational factor analysis, we studied of regionalization of the trends of annual, summer semiannual, and winter semiannual temperature changes for the four 30-year time periods, 1951-1980, 1961-1990, 1961-2000, and 1971-2010. The differences among the four periods of the regionalization were analyzed. The results show that China can be divided into 8 regions based on the characteristics of both annual and summer semiannual temperature changes, and the boundaries of the regions were stable during 1951-2010; the country can be divided into 7 regions based on the characteristics of winter semiannual temperature changes, and the boundaries of the regions showed clear changes in every 30-year time period. The regionalization boundaries of winter semiannual temperature changes showed high level of consistency with those of annual temperature changes. So winter semiannual temperature changes can substitute annual temperature changes for historical climate reconstruction. In addition, the characteristics of temperature changes in the different regions of China were analyzed. The results indicated that the trend of temperature change was overall upward, with a remarkable rate of 0.30℃/10a in Northeast and a rate of 0.13℃/10a in South China. Temperature increases of different regions were not in the same pace. For example, a significant warming trend in Northeast and Yunnan-Tibet Plateau was in 1961-1990, while warming trends of other regions were in 1971-2000 and 1981-2010. The winter semiannual temperatures had more dramatic increases than summer semiannual temperatures.
  • Global Change
    SHI Tiange, ZHANG Xiaolei, DU Hongru, ZHANG Wenbiao, SHI Hui
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    In the process of urbanization, urban spatial structure and organization mode are being transformed tremendously, and use of private cars causes traffic congestion and increased carbon emissions. It has become a hot research topic to investigate the relationships between urban spatial structure, residents' outings and carbon emissions from the perspective of micro-mechanisms. In this paper, based on a survey of daily activities of 600 households' from Urumqi City in 2011, basic characteristics of the residents' outings and spatial characteristics of their commuting were analyzed. In addition, the outing-related transport carbon emissions and the influencing factors in different urban areas were examined. The survey covered the activities recorded in consecutive 48 hours including a Sunday and a Monday. The results indicated that: (1) Urumqi residents' outings are mainly commuting. Outings in different areas show spatial diversity: the numbers of trips per capita in the two areas, the central area of inner city and suburban satellite towns, are higher than those in other areas, but the total trip distances in the two areas are significantly shorter than those in other areas. Imbalance of urban development between northern areas and southern areas affect suburbanites' outings. The residents in the areas are more dependent on the central city areas for jobs and services, due to lack of public service infrastructures in southern suburbs, whereas the residents in the northern suburbs tend to work near their own living areas, thanks to adequate employment opportunities and service facilities. (2) In comparison to the large cities on the east, the average actual commuting distance in Urumqi is 4.9 km, shorter commuting distance but longer commuting time. Commuting distance in space shows a significant increasing trend from inner areas to outer areas. (3) The direct carbon emission per capita from residents' daily outings in Urumqi was 682.95 g in 2011. Carbon emissions from residents' daily outings vary significantly in different urban areas, with low-carbon emission in the central area and the satellite towns, moderate-carbon emission in near suburbs and high-carbon emission in far suburbs.
  • Application of RS and GIS Model
  • Application of RS and GIS Model
    LIU Tiantian, LIU Ronggao, GE Quansheng
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    Lake Chad, on the border of the Sahara desert in central Africa, is well known for its high sensitivity to hydroclimatic events. Over the last 40 years, Lake Chad, once the sixth largest lake in the world, has shrunk by more than 90% in area. In this paper, variations of the open water areas, extracted from multi-source remote sensing data during 1973-2012, are analyzed. The results showed that in general Lake Chad was getting smaller and smaller during 1973-2012. Between 1973 and 1975 its area sharply reduced by about 71%. From then on its area ranges from 2000 km2 to 5000 km2. In order to validate the reliability of the trends, this paper first compares it with Birkett's results to analyze area accuracy, and next compares the results of MODIS with Landsat and AVHRR to validate the comparability of multi-source data, and last monitors monthly variation of Lake Chad area to validate the feasibility of multi-temporal data. Meteorological data analysis showed that the area of Lake Chad and the fluctuation of annual precipitation were in good correlation. Secondly, a large number of reservoirs built are another important cause of area reduction. Lastly, the Great Barrier that divided the lake into two smaller lakes has made it more vulnerable to water loss.
  • Application of RS and GIS Model
    WU Jiansheng, CHEN Sha, PENG Jian
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    Ice storms are one of the severe disruptions to forest ecological systems, causing vegetation loss and reduction of the ecological systems' functions. For this reason it is vital to assess the damages to forests after ice storms. Using SPOT Normalized Difference Vegetation Index(NDVI) time serial images of Yunnan Province of China during 2000-2011, forest damage caused by ice storms in 2008 was assessed based on image thresholding techniques of post-storm NDVI time series after Savitzky-Golay filtering by TIMESAT software. The damage threshold was determined by the difference of standard deviation between the years with ice storms and those without, which eventually turned out to be 21%. The range of extracted forest damage is almost consistent with the ice storm extent of Yunnan in the national monthly disaster report, therefore the result is reliable. The destroyed vegetation accounted for 12.09% of the total area of forest. Forest within Diqing County and Nujiang County, in northwest Yunnan, suffered the most losses. On the whole, seven counties took the worst hit by the natural adversity, while thirteen were moderately affected and forty five slightly affected. The most severe damage of forest occurred at the elevation of 3300 m to 4000 m, the slope of 5 to 15 degree, the middle slope position and the east or northeast aspect. Even so, it had little to do with slope position because the most of vegetation is located in the middle slope position. In-situ measurement was not employed here to verify the results because of time and money limits, which compromised the overall accuracy. However, with the acceptable precision, the research method can be used as a real-time forest loss assessment, which is of great significance for taking effective measures to avoid secondary impacts and starting the process of recovery.
  • Application of RS and GIS Model
    SHE Bing, ZHU Xinyan, GUO Wei, XU Xiao
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    Large amounts of data of historical events have been accumulated for many years through the operations of the Urban Grid Management System. These events are spatially aggregated. By examining the spatial distribution of these events and measuring the corresponding aggregation levels, we can provide important support for making sound decisions on allocation and distribution of urban management resources. Spatial point pattern analysis studies the distribution patterns of geographical point entities or events, and has been widely used in various disciplines including criminal statistics, ecology and public health. In this paper, we investigated two major types of city management events in Jianghan District, Wuhan City, traffic-blocking stall and garbage disposal events, from January to August in 2011. The results show that: the number of hotspots with traffic-blocking stall events had a decreasing trend, while that of garbage disposal events had an increasing trend. Both types of events presented significant spatial aggregation with roughly the same spatial scale of 1000 m. The spatiotemporal aggregation index indicated strong spatiotemporal correlations for both types of events where the space difference is below 500 m and time difference below 3 hours. The research shows that: with the help of spatial point pattern analysis, we can provide city managers with efficient visual analytics tools to identify spatial aggregation patterns of the events, and a quantitative method to measure the degree of spatial aggregation, which also lays a foundation for further statistical modeling.
  • Application of RS and GIS Model
    ZHANG Jing, PU Lijie, ZHU Ming, XU Yan, LI Peng
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    Land use system is the product of natural and human activities, and typically as a complex nonlinear dynamical system, its structure is irregular, unstable, complex and non-linear. Fractal theory, as a new technique, has been proved to be practical for analyzing irregular and nonlinear objects. The fractal dimension, one of the most important indices in fractal theory, is often calculated from raster data, but most land-use data are stored as vector data. Conversion of vector data to grid images to calculate fractal dimension may result in inaccurate values. Accuracy of the calculation on raster data is closely related to the grain size of the grid images. Taking a case study of the 1:100000 land use data of Suzhou City in 2008, this paper first analyzed the fractal characteristics of the study area by calculating the fractal dimension, investigated the scale effects of land use fractal dimension by changing the grain size of raster data, and then established a quantitative relationship between fractal dimension and the grain size, and lastly used the math model to calculate fractal dimensions from vector data based on the raster data. The results showed that land use structure of Suzhou City followed the general rules of fractal theory, which proved that this method was suitable for the analysis of the characteristics of land use system in such a rapidly urbanizing area. Furthermore, the overall land use degree of Suzhou City was high; human activities have different effects on the different land types. For example, under the influence of human activities the structures of arable land and construction land were relatively simple, but unused land and forest-grassland are quite complex. The morphology of water was less complex than other land use types, indicating that water was more affected by human activities such as water conservation facilities and irrigation ditches. The effect of the grain size on the fractal dimension in this area showed that the fractal dimension increased with expanding grain size, and the result of statistical analysis suggested that the relationship between fractal dimension and the grain size fit with the quadratic-polynomial-model which provided a bridge between the vector data and raster date for the calculation of the fractal dimension. If the vector data were viewed as raster data of 0 m grain size, vector fractal dimension can be calculated from raster data according to the quadratic-polynomial-model. The difference between the calculated results and the fractal dimension values directly using the vector data was minimal. Thus, fractal dimension of vector land use data (the grain size is 0 m×0 m) could be deduced by this relationship within the margin of error.
  • Tourism and Leisure Geography
  • Tourism and Leisure Geography
    LUAN Fuming, ZHANG Xiaolei, YANG Zhaoping, XIONG Heigang, HAN Fang, WANG Zhaoguo
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    In this paper, by using geostatistical methods, such as semi-variance function and Kriging spatial interpolator method, we analyzed temporal-spatial distribution pattern, structural characteristics and variability of tourism festivals in Shandong Province in 1990, 1999, 2005 and 2011, and established suitable models. Based on quantitative analyses, we made the conclusions as follows: (1) Spatial distribution of the numbers of tourism festivals is significantly imbalanced, showing an overall "high in the east, low in the west" pattern with the shape of a three-step ladder. (2) There are clear spatial structural characteristics in terms of correlations of the events, with positive and negative correlations existing simultaneously. When the separation distance gets longer, the positive spatial correlation decreases, and in the meantime negative correlation increases. (3) Compared to 1990, the value of partial sill increased by 20.61 times in 2011; variable range increased from 115.5 km to 335 km; structural variance ratio decreased from 69% to 26%; the impact of random factors weakened, but the role of structural factors strengthened. (4) In terms of spatial fractal dimension, the values trended down and the spatial variations increased in all directions. The most significant variation was in the east-west direction; the rest of the directions were relatively balanced, showing a spatial development pattern with the characteristics of plate-like and anisotropic distribution. (5) Three main factors contribute to the evolvement of developmental variability of tourism festivals in Shandong Province: level of economic development, tourism supply capacity, and transportation accessibility.
  • Tourism and Leisure Geography
    SANG Lijie, SHU Yonggang, ZHU Weiping, SU Fei
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    Urban leisure green space is a typical green open space very important for maintenance of urban ecological security and human health. Accessibility to urban leisure green spaces directly affects the quality of services for city dwellers and reflects the region's urbanization level. Accessibility to urban green spaces can be used as an indicator to assess the effectiveness of providing ecological services to residents of the green areas in current system and long-term future system. With socio-economic development, Chinese people and governments are paying much more attention to urban green spaces, and more and more citizens have the desire of contact with nature, and are willing to live close to urban green spaces. Consequently, governments plan to develop and optimize urban green space allocation to meet these demands. In this paper, a quantitative method based on landscape accessibility of green space in Hangzhou City was employed to improve index systems. Aided by GIS technique, this paper conducts analysis on the accessibility and service ability which considers the population densities of every district, applying the methods of buffer zone, minimum distance and travel. The results indicate that: (1) In Hangzhou City, on average it takes 3.8 minutes from a residential area to a urban leisure green space, and 92.11 percent of urban residents have access to a leisure green space within 10 minutes; the residential areas with poor accessibility are the outskirt areas of the city. (2) As to scenic-spot green spaces, their accessible time is 20.33 minutes. Xihu and Xixi are found to be much more accessible than other scenic spots. (3) The accessibility exhibits a structure of annulations centered around Xihu, the farther the distance is away from Xihu, the poorer the accessibility is. The work of this paper will help improve the key index system for assessing urban green spaces in China, and can provide planners and policymakers with important and valuable information for urban green space planning and assessment.
  • Tourism and Leisure Geography
    YIN Guowei
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    Based on graphic analysis and density calculation, this paper studies the characteristics of the spatial distribution of world heritage sites, mainly cultural and natural heritage, of Africa at continental, regional and state levels. As of 2012, a total of 126 sites in Africa are included in the World Heritage List. In 1978, world heritage sites from Africa were added to the World Heritage List for the first time, followed by a burst of number increase for a short period of time. After that, for many years it has been slow in terms of new heritage sites being added. Now it is the time to explore the characteristics of the spatial distribution of world heritage sites in Africa, and the study provides a reference for site selections in the interactions and exchanges with African states. The study has found that the world heritage sites are relatively concentrated on the continental coasts and islands, in mid-size river basins and eastern local areas, with higher densities in Eastern, Northern and Western, and the highest in Eastern Africa. Among the states, Senegal, Tunisia, Gambia, Cape Verde, Mauritius and the Seychelles have the highest densities, followed by C?te d'Ivoire, Morocco, Togo, Kenya, Uganda, Malawi, Zimbabwe and other states. Except for Malawi, Zimbabwe and Mauritius, the states with higher density of cultural heritage sites, including Egypt, Morocco, Tunisia, Senegal, Benin, Ghana, Togo, the Gambia, Cape Verde, Ethiopia, Kenya and other states are in Eastern, Western and Northern Africa. The corridor of Cameroon-Central Africa- Democratic Republic of Congo is the region rich natural heritage. At the regional level, except for Northern Africa, there are higher densities of natural heritage sites in other regions, with the highest density in Eastern Africa. At the state level, except for Tunisia, the states with higher densities of natural heritage sites, including Niger, Guinea, C?te d'Ivoire, Senegal, Cameroon, the Central African Republic, Democratic Republic of the Congo, Tanzania, Kenya, Seychelles, Uganda, Madagascar, South Africa, Zimbabwe and Malawi are in those regions. In addition, the distribution and density of world heritage sites at the regional level and the state level are showing good overlap.
  • Tourism and Leisure Geography
    CHEN Chao, LIU Jiaming, CHEN Nan
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    Development of rural tourism provides an approach to solving the problems with agriculture, farmers and rural areas. Implementation of the standards for the rural tourism quality rating system helps promote the transformation of the traditional rural areas and agriculture resources into collective farms and industrial operations, and helps ensure a sustainable rural tourism development. In this paper, in the context of regional cooperation, we compared the evaluation categories of rural tourism quality standards among the four provinces on the west coast of Taiwan Strait, and found that creation and evaluation of rural tourism quality standards are different in different areas, which hinders the integrated development of the rural tourism industry. It is important to establish the criteria for the tourism products of the same level and quality based on demands and feedback of tourists. The framework of the evaluation system should contain three major components: mechanisms of allocation and cooperation of the functions of stakeholders, examination of the comparable indices of tourism quality, and assessment of the core values of tourism products, in order to further specify and improve the rural tourism quality standards, and to promote the integrated development of star region of rural tourism on the west coast of Taiwan strait. As a typical case, this study serves as a guide for a standardized rural tourism development.
  • Tourism and Leisure Geography
    QI Tong, WANG Yajuan, WANG Weihua
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    Visual landscape study has a wide application prospect in the construction of scenic spots as well as urban and rural planning and management. Related foreign researches in the last decade were reviewed and divided into three parts in this paper: visual landscape quality assessment, visual impact assessment, and visual landscape preference. The basic implications and theoretical sources were introduced. This paper mainly concerns the topics, methods and techniques of each field. At the same time, advantages, disadvantages as well as relevant significance were analyzed. First, in landscape quality assessment, the research emphasis was the contribution of landscape elements and features to landscape quality. Psychophysical approaches were commonly used in this area, but there was an apparent tendency toward combination of the expert-based approach and the psychophysical approach. Secondly, visual impact caused by urban and rural buildings and renewable-energy facilities received much attention. GIS and 3D visualization techniques enlarged temporal-spatial scales and improved the precision of quality and impact assessment. Thirdly, scholars investigated visual landscape preference from two perspectives: human and landscape which was respectively subjective and objective part of appreciation. Not only human natural and cultural attributes but also landscape features were deeply explored to demonstrate the influence in landscape preference. It was confirmed that landscape preference could promote landscape preservation and rational land use. In conclusion, the progresses of the studies on visual landscape were summarized as follows: visual landscape study was more instructive in landscape planning and construction, because the subjective and objective methods were gradually integrated and the techniques were diversified; study areas were unbalanced and study objects were a little dull, so more relevant researches should be made in the developing countries and scholars should pay much attention to visual impact of a large variety of landscape types; there was a need for comprehensive perspectives as the number of interdisciplinary studies was increasing; the foreign researches had some enlightenment for the domestic ones.
  • Tourism and Leisure Geography
    TANG Chengcai, ZHONG Linsheng, CHENG Shengkui
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    With the rapid development of tourism, various resource and environmental problems have been constantly emerging in tourism destination areas. The research on sustainable development of tourism destinations can promote the optimization of comprehensive benefit and the exertion of ecosystem service function for tourism destinations. There have been abundant achievements in the research on sustainable development of tourism destinations at home and abroad. The research progress was reviewed from the three aspects in this paper, including research process, research methods and main research content. Firstly, the course of the research at home and abroad was summarized and divided into three phases: initial exploration, rapid development, consolidation and deepening. Secondly, main research methods were analyzed comprehensively in terms of their characteristics and the insufficiency, which include tourism environment capacity evaluation, tourism environment impact evaluation, evaluation indices, limits of acceptable change, tourism ecology footprint. Thirdly, the major research contexts were reviewed from seven aspects, including the concepts and the level of sustainable development of tourism destinations, the course and the mechanism of the development of tourism destinations, carrying capacity and ecosystem safety of the environment of tourism destinations, tourism sustainable development model, local residents' and visitors' perceptions of the impacts of tourism, low-carbon development of tourism destinations, and the impacts of tourism enterprises. Finally, the perspectives of the research on sustainable development of tourism destinations in China were put forward from the aspects of theory, methods, and content.