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  • Orginal Article
    Lin LIU, Gang-bin YANG, Shen-jing HE
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    Based on a large-scale household survey conducted in low-income urban neighborhoods in three large Chinese cities, i.e. Guangzhou, Wuhan and Xi′an, this study examines China′s low income urban neighborhoods’ between-group and within-group housing differentiation defined by different socioeconomic characteristics, and analyzes various determinants of housing differentiation under market transition, including institutional factors (hukou, neighborhood type, employer type, etc.) and market factors (social group, age, education, Household income, occupation, etc.). This study aims to present a comprehensive portrait of housing differentiation in low-income urban neighborhoods, and to understand how the confluence of state and market forces contribute to housing differentiation. The merits of this study mainly lie in two aspects: first, based on first-hand data source, this article presents a meticulous examination of housing differentiation within and between groups categorized by various indicators; second, this study enriches our understanding of the role of institutional and market forces by providing a more accurate assessment on their respective impacts on different aspects of housing differentiation. In this study, we applied various statistical models to analyze different social groups’ housing differentiation on the housing tenure and housing conditions. Theil′s index is applied to measuring the degree of residential differentiation between and within groups on housing tenure and housing conditions, while multivariate regression model is used to explain the causes of housing conditions differentiation. According to the Theil′s T statistics, the differentiation of housing tenure is most significant among people with different hukou status. These findings suggest that housing tenure differentiation is predominantly shaped by institutional factors, while the impact of market remuneration system, e.g. educational attainment and household income, is comparatively less significant. The patterns of differentiation are slightly different when it is measured by housing conditions. In terms of between group differentiation in housing conditions, groups defined by hukou status, household income, and different cities show a high degree of differentiation. In comparison, between group differentiation is much less significant than within group differentiation. This could be partly explained by the fact that various social groups in Chinese cities are generally characterized by high degree of heterogeneity and mobility under market transition. This is particularly true among residents in low-income neighborhoods, which are highly fluid, volatile, and heterogeneous, although they might become more homogeneous once all better-off residents have moved out. The multivariate regression analyses reveal that the forces from market and the state have brought about different imprints on various aspects of housing status. Institutional factors have projected more significant impacts on some costly and durable housing indicators, which are less likely to change in a short period, such as housing tenure and housing area, while socio-economic determinants are more influential on housing facilities which are comparatively easy to be improved. Concurring with extant literature, this study shows that institutional heritages from the socialist period continue to shape the patterns of housing consumption in post-reform large Chinese cities, although the newly emerged urban housing market starts to play increasing important roles. In addition, this research presents a much more detailed portrait of housing differentiation in low income neighborhoods. This paper has added much richness and nuance to extant understanding of housing differentiation under market transition.

  • Orginal Article
    Xin-sheng FAN, Xiao-jian LI, Geng-he GAO, Qing LUO
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    The activity spaces for labor forces of rural households are divided into four categories in this article: Locality, village, region and nation. Locality activity space is confined to rural households own farm. Village activity space consists of various stakeholders located in one village including all of the rural households, factories and natural resources. Region activity space is defined as the area within a 30 km radius of one village. The rest is Nation activity space. Rural households always make a living in one or more activity spaces. Activity space strategy of rural households are analyzed according to sample survey from Henan Province. Tthe mechanism and degree of influence that family characteristics and geographical conditions exerting on activity strategy choice of rural households are explored by using a Multinomial Logistic Regression model with activity space strategy as the independent variable and location (distance from the nearest city), education level, quantity of labor force, per farmland, accessibility, economic development level of town as the dependent variables. The results are as follows: 1) Rural households tend to allocate their labor forces to different activity spaces and choice diversifying activity space strategy. In general, with making a living in locality space, rural households always get cash income from one or more activity spaces among village, region and nation spaces at the same time. But in most cases only one activity space plays a major role in rural households’ cash income. Compared to other activity spaces, average wages in nation activity space are highest. So the rural households involving in nation activity space always rank among the high-income class compared to others. The self-employed rural households always get high income too, but their activity spaces are confined to locality and region spaces. 2) The quantity of labor force affects space strategy choice of rural households significantly. The more labor forces rural households, the higher probability of diversifying activity space strategy. 3) Because jobs engaged in by labor force of rural households are characterized by "dirty, danger and hard", high education level is not important for these jobs. Statistically there is significant linkage between activity strategy choice and middle education level(primary schools and the junior middle schools). 4) Because of small farm size, farming output value has little contribution to rural households income growth, so farm size dosen′t play a major role in decision-making.5) Good spatial accessibility of transportation facilities can promote more economic activities in Region activity space. 6) As a whole, economic development level of most sample towns is low and has no distinctive effect on activity space strategy choice of rural households. 7) "Location" affects activity space strategy choice of rural households significantly. The rural households close to city can get jobs or self-employment chances in region and locality space easily.

  • Orginal Article
    Jia-dong YUAN, Shao-feng LIU
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    When did human begin to appear in the Ryukyu Islands? Where did Ryukyu people come from? Was Ryukyuan an independent nation or just a branch of Yamato? These questions about Ryukyuan nature are still under debating at present. Using literature analysis and comprehensive analysis method, author of this paper analyzed and evaluated the previous archaeology, cultural anthropology and population genetics studies about Ryukyu people. This article is trying to reveal the human origins and migrations in the Ryukyu Islands and the genetic relationship between Ryukyu people and other ethnic groups in East Asia. Archaeological findings pointed out that traces of human activities appeared in the Ryukyu Islands as early as Paleolithic period. The human mitochondrial DNA and Y chromosome analyses and the genome comparative researches proved that ancient humans migrated to the Southeast Asia from Africa at the late Pleistocene. Afterwards they spreaded to Japanese archipelago and the Ryukyu Islands and became the ancestry of modern Japanese and the Ryukyu people. The genetic relationship between Ryukyu people and Japanese is very close and both retain biological genetic characteristics of Ainu. Archaeology and cultural anthropology for similar culture analyses evidenced that there was a close relationship between the culture of northern the Ryukyu Islands and the Jyomon culture of Japan, but the southern Ryukyu culture was closer to the Austronesian culture. In addition, after the 14th century, some cultural factors from mainland China, Korean Peninsula as well as Southeast Asia began to penetrate into the traditional culture of the Ryukyu Islands through trade exchange with these countries.

  • Orginal Article
    Zhi-bin ZHANG, Ying YANG, Cui-ping JU, Chun-yu DENG
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    Based on demographic data at a street level from 1982 to 2010 of Lanzhou, the essay analyzes the spatial evolution of Hui population spatial structure and social response in Lanzhou, by a comprehensive application of inverse distance weighted (IDW),spatial correlation analysis and other methods, combined with software ArcGIS 9.0 and GS+ Version7.The results show: firstly,the overall distribution of the Hui population shows " double columnar peak body " structure, with a major peak body, another minor peak body, and population is increasing between the two columnar peak body. Secondly, the spatial distribution of the Hui population between neighborhoods showed a strong correlation, and the spatial concentration trend is strengthening. Population spatial structure is relatively stable. Hot spots are located in the old city, and the scope expanded to the east-west direction, but the transition was not apparent phenomenon. Cold spots are located in the old city periphery. The scope is gradually shrinking and westward shift, and cold spots are distributed in the Anning and Xigu areas. The spatial distribution of the Hui population growth rate between neighborhoods showed a weak positive correlation. Population growth pattern is likely to be more stochastic and unstable. The growth of hotspots range continues to shrink and are locate on the edge of the city. The growth of cold spots are mainly locate in the old city with the scope expanding. There are five blocks remain unchanged. On the basis, the article systematically summarizes the social response to the spatial evolution of the Hui population from four perspectives which inheriting national cultural heritage, enhancing the city inclusive, booming urban economy and building a harmonious society. This article think that with the geopolitical structure evolving from the dwelling around the mosque into the dwelling near the mosque, and the social structure evolving from "intensely segregated" into "relatively integration", and because the difference of religious beliefs, ethnic ,cultural and habits of living, it is difficult to avoid the friction or conflict between Hui and other ethnic groups in the long run. Therefore, intensifing efforts on cultivating and invest in national culture and national facilities, making full use of the Hui Muslim cultural resources to form a set of the Hui′s goods, customs and travels, arts and cultures as one of the "national style" industrial chain, transforming the cultural capital into economic capital, continuous digesting the growing serious cultural discomfort and even cultural conflict of Muslim population, and enhancing the city adaptability of the Hui Muslim, will be long and arduous task in the future.

  • Orginal Article
    Hao YE, Da-chang ZHUANG, Hui-xia ZHANG
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    This article gives both details and overview of research development and analytical methods in urban systems. Then this article describes the spatial distribution pattern of urban system based on the data of the Chinese cities at the prefecture level or above in 2011. The conclusions can be drawn as follows. 1) The proportion of secondary industry employment is roughly equal to the tertiary industries of the Chinese cities at the prefecture level or above and the proportion of manufacturing industry is highest. There exits a large difference among cities with different sizes. The tertiary industry′s polarization phenomenon is more obvious. With the increase of city size, the number of city functions has significantly increased. It′s to verify the theoretical assumptions of the central place theory. 2) Urban system′s α diversity of provinces are quite different. Provinces with high α diversity index mainly distributed in the central and eastern regions. It is mainly affected by the regional population density, while there is no significant relationship with per capita GDP and urbanization ratio. 3) The majority of two adjacent transects′β diversity index were relatively small compared with those of the two other groups, it is indicating that the type of urban structure changes substantially along the population density, but cities in transects with population density of 800-900/km2 and 300-400/km2 have more unique urban type structure. 4) From the computing results of γ diversity index, spatial distribution diversity of the cities with resources, manufacturing or building role in the secondary industry is low, and space distribution of the cities with various functions in the tertiary industry is relatively uniform.

  • Orginal Article
    Zheng-shan DING, Yi WANG, Zheng-yong SHANG, Ya-ru LI, Xiao-yu SONG, Xia-jie CHANG
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    Taking towns of Changshu as the case region, mainly based on Generalized Principal Component Analysis, Spatial Gini-coefficient, Krugeman specialization index and other methods and indicators, this article measured the model of locality distribution, the industrial characteristics, the specialized rate of producer service industry in each town of this region from 2007 to 2011. The results indicate that the general spatial distribution shows itself to be the situation of a typical single center, large gradient-level development trend. Compared with Suzhou, the degree of agglomeration of producer service in Changshu was not very high and its agglomeration trend was not obvious. There are big structure differences among internal sectors in producer service industry and the division of labor based on specialization in each town is distinct. Compared with Suzhou, the whole producer service of Changshu didn’t have obvious specialization advantages. Among all the producer service industry, the specialization rate of all producer service industry were low except for transportation, warehousing and postal service, as well as the real estate industry.

  • Orginal Article
    Ying ZHAO, Yan-wei CHAI, DIJST Martin
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    There is a long history to draw big distinctions of cultures between West and East with the constructs of individualism and collectivism. This coincides with a growing awareness that society change diversified in the process of modernization from the perspective of activity-travel behavior, but limited attention has been paid to investigation of companionship choice for non-work activity and travel. This article contributes to the knowledge on how to examine cultural differences by presenting estimation of companionship choice in activity-travel behavior, based on activity diary surveys collected in Beijing (China) and Utrecht (the Netherlands) both in 2007. The types of companionship could be divided into 4 categories, including alone, friend, core family member and other family members, which present the ordered degree from individualized to collective tendencies. According to descriptive analysis, the companionship share shows people in Beijing perform more often with others, yet those in Utrecht tend to perform more alone. If accompanied, people in Beijing conduct more activities with family members, but people in Utrecht conduct more with friends. Other family members dominate a considerable percentage as companions in Beijing but not in Utrecht. The findings indicate that people in Beijing behave more collectively, yet people in Utrecht behave more individually. According to MNL estimation, it shows important differences observed on socio-demographic, life cycle and activity type. In Beijing, women with cars from ‘big families’ are likely to conduct more leisure and social activities with family members, while older men tend to have more joint activity with other families or friends. These results are associated with Confucian culture and strong family tradition in Chinese society. In Utrecht, high-income men with cars from single families are likely to conduct more activities alone. These respond to independent life style in the Netherlands. In both two cities, people from couple or core families with young kids tend to perform activity with core family members, which shows family-obligation is an important factor for companionship. For the influence of activity types, the result shows leisure or social purposes encourage joint activity, particularly with friends. These findings are intended to provide evidence on collectivism is popular in Eastern society but individualism is prevalent in Western society. It discusses the social integration and value tendency in Chinese and Dutch society from activity-travel behavior perspective, and also points out some shortcomings in this article supposed as a stimulant for further analysis on cultural differences.

  • Orginal Article
    Hong-xia ZHANG, Xue-zhen WANG
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    This article firstly employed variation coefficient to analyze the evolution of regional economic gap in Shandong province from 1989 to 2012, and then used Theil entropy to statistically decompose the gap sources and composition. Study demonstrated that: 1) Regional economic gap in Shandong has appeared as an inverted "U" type trajectory during 1989-2012, specifically divergence in 1989-2003 and convergence in 2004-2012. In addition, the regional economic gap in final observation phase was greater than that in the beginning phase. 2) From the zone-gap composition, intra-zone gap was the main source of regional economic gap in Shandong, accounting for more than 80% of it each year, even 85% in 1989-2004. Among the intra-zone gap, contribution was mainly from east and west zone of Shandong, of which more than 44% from eastern Shandong each year and over 31% from western Shandong in 1989-2009. While contribution from inter-zone gap declined year by year, it was 19.17% in 1989 and 14.34% in 2012. Therefore, internal gap in the east zone dominated intra-zone gap and constituted the major zone gap source in Shandong Province. 3) From the industry-gap composition, regional economic gap of Shandong mainly came from intra-industry gap, whose contribution to regional gap has been more than 56% each year, and exceeded 80% after year 1998. Among the intra-industry gap, the secondary industry and the tertiary industry constituted the major source, contribution from the secondary industry has exceeded 50% in 1989-2004, and that from the tertiary industry increased and has been more than 40% after 2010. Contributions from the three industries and inter-industry gap to regional economic disparities have shown certain characteristics of time variation. Firstly, primary industry in Shandong Province contributed little, though contribution rate in 1989-1991 was slightly higher. Secondly, influence of the secondary industry in 1989-2009 was dominant, but since 2005 the contribution has tended to decrease. Thirdly, the tertiary industry's contribution showed a continuous upward trend except in 2003 and 2004, and even exceeded the secondary industry in 2011 and 2012. Fourthly, the contribution of inter-industry gap showed up briefly trend in 1989-1991 and decreasing trend after 1992. In short, the imbalance of development of secondary industry and tertiary industry in different regions was the major sources of regional economic gap in Shandong Province. According to the above empirical results, policy recommendations are: 1) Industrial layout should be overall planned and factor endowments in different areas should be given an important consideration. The feasible industry in Shandong Province may be laid out as follows: the eastern area should gradually build up capital-intensive and knowledge-technology-intensive industries, the central area should mainly concentrate on resource-intensive and capital-intensive industries, while the western area should focus on labor-intensive and resource-intensive industries. 2) Economic policy should be further unified to promote competitive enterprises to cross-regional expansion and foster cross-regional industrial group, which will eventually bring industrial interaction among different administrative regions. 3) Education funding of the backward areas should be greatly increased to improve the local labor quality and form the superiority of labor resources for non-agricultural development.

  • Orginal Article
    Yao-guang ZHANG, Kai LIU, Gui-chun LIU, Ze-yu WANG, Guo-li WANG, Fei PENG
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    Administrative region is the area that local government has jurisdiction over. As a prefecture-level city in Hainan, Sansha has the smallest land area, the largest water area and the smallest population compared with other “city”-level administrative authority. The main reason of establishing Sansha City is to safeguard national maritime rights and interests, protect islands and reefs in South China Sea, exploit the abundant fishery resources, subsea oil and gas, marine tourism resources and subsea cultural relics in South China Sea. The history, location, the size and outline of the administrative region are recounted and described in this article. Compared with the city of Zhoushan, which is also a prefecture-level city composed of islands, Sansha′s land area is only 0.9% of that of Zhoushan, while water area is 96 times larger. Fishery resources, subsea oil and gas and tourism resources in Sansha are analyzed in this article. The numbers, areas and depth of the oil and gas areas open for bid are demonstrated by graphs and tables in particular. At the end, we propose that tourism, fishery, oil and gas and subsea cultural relics be the key industries to develop. And great importance should be attached to the marine ecological construction and environmental protection in the course of exploitation so as to attain sustainable and green development.

  • Orginal Article
    Lu ZHAO, Zuo-quan ZHAO
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    :This study described the spatial variation in China spatial explicitly through a series of ellipses according to Krugman's "first and second natural" theory. The ellipse of national geometric profile in China was taken as the original state of spatial variation. The first nature variation could be explained through the ellipse of topographical distribution in China, and the second nature variation was represented by the spatial distribution of population. The results are as followings. 1)The spatial variation is mainly between the eastern and the western area in China. The spatial coverage of topographical distribution ellipse is in the west, and it is much smaller than the equilibrium distribution ellipse which is in accordance with the topographical characteristics that the west is higher than the east in China. The population distribution ellipse is mainly covering the North China Plain and the Middle and Lower Yangtze Valley Plain and its spatial coverage is much smaller. It is proved the spatial variation of the first nature and the spatial agglomeration of the second nature. 2)The spatial variation from the first natural factors is significant in China. 93% of the population distribution ellipse range is located in the southeast of Hu's line, and the main axis is almost parallel to Hu's line. The spatial variation index of population distribution ellipse to the topographical distribution ellipse is 89.55%. 3)For the prefectural-level cities, the population ellipse and GDP ellipse are aggregated in the southeast of Hu's line which is 20% of the mainland area in China. There is the spatial disparity between the population and GDP distribution. In general, the natural endowments between the east and west in China resulted in the unbalanced beginning of regional development. It is shown that the regions in the north of Hu's line, especially in the northwest area, is weak to gathering the population. Meanwhile, spatial differences of the agglomeration which is the inner core of the regional developing momentum present the unbalanced process of regional development. From the perspective of both efficiency and equity, the promotion of Chengdu-Chongqing, Guanzhong and other major economic zones which is with the large population is relatively could stimulate the economic growth in central and western China, and to attract the population concentration in the north part of GDP distribution ellipse could promote the economy development from the south to the north. In addition, Standard deviation ellipse method can not only subtly describe the spatial variation of the different features, but also can quantitatively analyze the extent of spatial variation, and it is proved to be a new method for reference to study the economic spatial variation.

  • Orginal Article
    Feng YAN, Yan-jiao WANG, Bo WU
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    Agricultural drought is one of the most serious meteorological disasters in China. Temperature (Ts)-vegetation index (VI) featured space is an important method for soil moisture estimation and drought monitoring. In this paper, multi-time scales AQUA- MODIS products such as MYD11A1 with the day of year (DOY)148, MYD09GA (DOY:148), MYD11A2 (DOY:145), MYD09A1 (DOY:145) and MYD13A2 (DOY:137) acquired on May 28, 2011 were used to establish Ts-enhanced vegetation index (EVI) featured space with 1 d, 8 d and 16 d time scales. Besides, 36 in situ relative soil moisture (RSM) on May 28, 2011 and ASTER-GDEM2 data in Hebei Province were also used to study the diversity of drought monitoring. Results showed that: 1) Correlations between temperature vegetation drought index (TVDI) derived from multi-time scale Ts-EVI featured spaces and RSM varied significantly in different soil depths. Among them, the correlation of RSM20-TVDI was the highest, correlation of RSM10-TVDI was higher and that of RSM50-TVDI was the lowest. Relationships between RSM20 and TVDI derived from Ts-EVI featured spaces with multi-time scales showed that coefficients of determination of RSM-TVDI with Ts148-EVI148 and Ts148-EVI145 scales were relatively higher and those with Ts148-EVI137, Ts145-EVI145 and Ts145-EVI137 scales were relatively lower. 2) Among the 36 in situ RSM samples, 10 samples were used as test samples and the rest ones were used to establish the soil moisture estimation model RSM20-TVDI. Moreover, mean absolute error (MAE), mean relative error (MRE) and root mean square error (RMSE) were used as indices to evaluate RSM estimation abilities of the RSM20-TVDI model. Error tests showed that the maximums of MAE, MRE and RMSE of the RSM20-TVDI models from different time scales featured spaces were no more than 4.85%, 8.33% and 0.054, respectively. So the RSM20-TVDI model could estimate soil moisture successfully. 3) The spatial distributions of drought retrieved from Ts with 1d (Ts148) and 8d (Ts145) scales and EVI with 1 d (EVI148), 8 d (EVI145) and 16 d (EVI137) scales, respectively, showed good consistencies. Drought monitoring on May 28, 2011 showed that the mild drought regions mainly distributed in the northern parts of Langfang, northern of Cangzhou, southern of Hengshui, middle and southern of Xingtai and northern of Handan. Moderate drought regions mainly located in southwestern of Cangzhou and eastern of Xingtai. Severe and extreme drought regions mainly distributed in the southwestern parts of Baoding, southern of Shijiazhuang and the middle and northern of Handan. 4) Diversity existed in drought areas derived from Ts-EVI featured spaces with multi-time scales. For drought monitoring based on Ts-EVI featured space with MODIS products, on the condition that the data were available and with ideal quality, Ts and EVI with 1 d scale should be the first choice, then Ts with 1 d scale and EVI with 8 d scale, both Ts and EVI with 8 d scale, and Ts with 1 d or 8 d and EVI with 16 d scales should be the last choice.

  • Orginal Article
    Ye XIAO, Li-na SHANG, Zhi-gang HUANG, Wen-guang ZHANG, Zheng-shan XUE, Zhong-sheng ZHANG, Xian-guo LU
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    :Wetland soil organic carbon, nitrogen and phosphorus content significantly affect the productivity of ecosystem. To clarify spatial distribution characteristics of soil nutrients in mountain swamps located in eastern part of Jilin province, four typical swamps (Larix-carex swamp (T1), Scyperus dulourii swamp (T2), Calamagrastis angustifolia-glyceria acutiflora swamp (T3) and Paludification meadows (T4)) were selected in Dunhua city. In these swamps, we analyzed the spatical distribution characteristic of soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) content and theirs stoichiometric ratios and influencing factors. The average contents of SOC, TN and TP in the four swamp types were 343.11 mg/g, 28.03 mg/g and 4.00 mg/g, and the trends of variation coefficient were SOC (9.26%) < TN (16.52%) < TP (48.64%). The profile change trend of SOC, TN, TP contents presented an ‘increased-decreased’ unimodal curve during 0-40 cm soil layer and the peak values existed in 10-20 cm soil layer under T1, T2 and T3. While the contents of SOC, TN and TP under T4 decreased coupling with soil depth. In the study area, the change trends of SOC and TN contents were as follows: T1<T2<T4<T3. Linear relationship about SOC and TN, SOC and TP, TN and TP existed in the four typical swamps, and the change of TP lagged behind SOC and TN. The trends of TP content and the ratio of C/N, C/P and N/P under the four typical swamps were as follows: T1<T2<T3<T4. Correlation analysis showed that soil moisture content was the key influencing factor which caused the changes of C/P and N/P ratio in the four typical swamps. However, C/N ratio was not significantly affected by other environmental factors.

  • Orginal Article
    Wen-xiong JIA, Yu-shun ZHANG, Zong-xing LI
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    Based on the daily precipitation of 18 weather stations in Qilian Mountains and Hexi Corridor in 1960-2009, the temporal and spatial changes of precipitation extremes were analyzed by using methods of linear trend, ten moving trend and Mann-Kendall and thirteen indexes of precipitation extremes. The results indicated that the day numbers and amounts of precipitation extreme are on increasing, and this is contrary to intensities of precipitation extremes. Consecutive dry days and consecutive wet days are on decreasing, but max one day precipitation amount and max five day precipitation amount are on increasing. The change trends of precipitation extremes existed certain regional differences that the precipitation amount increased obviously and the variability of precipitation decreased gradually in the middle and west of Hexi Corridor, that the day numbers and the degrees of precipitation extremes increased in the middle of Hexi Corridor, that the amounts and the degrees increased in the east of Hexi Corridor and Qilian Mountains, and that the amounts and the degrees increased obviously in the middle of Qilian Mountains where it is most sensitive to global warming than other regions. The indexes of precipitation extreme changed abruptly in the middle of 1960s, the middle of 1970s, the first of 1980s, the middle and later of 1980s and the middle of 1990s. The abrupt spots are consistent to the times of the strong and weak change of East Asia Monsoon, South Asia Monsoon and Westerly Wind circulation.

  • Orginal Article
    Jun ZOU, Wen-wu ZHANG, Yu-rong YANG
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    The traditional econometric model is mostly utilized in water resources vulnerability assessment field. In recent years, the author and his research teams have studied the water resources vulnerability problem in Hengyang Basin using the traditional method. In order to explore better water resources vulnerability quantitative assessment method, in this article, GIS and RS technology was used to evaluated the vulnerability of water resources system in Hengyang Basin. Using GIS/RS method, take Hengyang Basin as the research region, construct a water resource vulnerability evaluation index system based on GIS and RS which contains natural vulnerability (NV), human vulnerability (HV) and burden vulnerability (BV) three aspects and include average precipitation, drought index during 7-9, slope index, soil water storage ability index, vegetation index, land use index, water availability index and human activity index 8 specific index. The index system has great differences to the indicator system of the traditional method. Firstly, use the human activity index to replace the series of index in original social and economic aspects of the traditional method. Secondly, increase water resources availability index and land use index to replace series of indicators about artificial vulnerability index in traditional method. Eight thematic data layers were generated after index data digitization and layer edit processing. Water resource vulnerability of Hengyang Basin was calculated using the spatial analysis model. The results show that water resources system vulnerability space distribution shows the situation of "north and south low, middle high", Hengyang in the north, Qidong in the west and Hengnan in the centeris the highest water resource vulnerability areas. And LeiYang in the sourth, and Hengdong in the northeastis the water resource vulnerability low value areas. The evaluation results have good similarity between water resource vulnerability evaluation method based on the GIS/RS and the traditional research method. However, compared with the traditional evaluation method, the results of the evaluation of GIS method was more detailed and accurate. and this method has a larger advantage in data processing, once regional related indicators database was established, evaluation process will become very convenient and easy. At the same time, this method has the advantages of vulnerability dynamic change assessment because of many indexes data can get from the remote sensing image, which is easy to obtain the dynamic changes of the regional water resource vulnerability in the different periods. The research shows that the GIS/RS method in water vulnerability assessment has better reliability. Therefore, the method based on GIS and RS is the important development trend of the regional water resource vulnerability assessment.

  • Orginal Article
    Guo-liang LEI, Yun ZHU, Xiu-yang JIANG, Zhi-zhong LI, Jian-hui JIN, Ke-yan FANG, Rui-qing SONG
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    We investigated the local climatic change in the central Fujian Province, eastern subtropical China, and its linkages with large-scale Asian monsoon dynamics using an &#x003b1;-cellulose &#x003b4;13C record of a 358cm peat core in Xianshan Mountain of Pingnan County(118&#x000b0;42.7&#x02032;E,26&#x000b0;52.4&#x02032;N). Conspicuous changes of &#x003b4;13C are observed ranging from -26.6&#x02030; to -11.3&#x02030; in our sedimental record, which is controlled by the local sedimental environment and the change of precipitation. During the periods with abundant precipitation, an under-water sedimental environment can be formed in the basin and organic carbon in peat core is originated from submerged plants that have positive anomalies of &#x003b4;13C. Otherwise, organic carbon is originated from C3 plants, resulting in low &#x003b4;13C. Based on the AMS datings, high-resolution peat record was used to reconstruct the past climate changes over the past 1400 years, which was dry (AD 600-910), wet (AD 910-1640) and dry (AD 1640 to present). On multi-decadal to centennial scales in the last millennium, it is showed that each dry period corresponds to the period with minimum solar activity, which was known as Medieval Minimum (AD 640-710), Oort Minimum (AD 1010-1050), Wolf Minimum (AD 1280-1340), Sp&#x000f6;rer Minimum (AD 1420-1530), Maunder Minimum (AD 1645-1715) and Dalton Minimum (AD 1795-1820). The good correlation between &#x003b1;-cellulose &#x003b4;13C and solar activity indicates that the precipitation of Xianshan may be largely ascribed to the control of solar activity, which advanced the knowledge about local precipitation forecast of eastern subtropical China.