The spatial evolution of manufacturing is one of the focuses of economic geographers. Using Chinese industrial enterprises data and panel data regression model, this article investigates the effect of labor market transition on the spatial transfer of Chinese manufacturing. The main conclusions are as follows: firstly, the rising labor cost has becoming a key factor that has an influence on the spatial transfer of Chinese manufacturing. The industrial agglomeration in developed area was not affected by the relatively high labor costs before 2004, but after 2004, the rising labor cost in developed area drove enterprises, no matter export-oriented enterprises or enterprises that served domestic marked, to migrate to relatively less developed areas with relatively low labor costs. Secondly, the flying geese pattern has occurred in China. Before 2004, China's manufacturing continuously agglomerated to the Yangtze River Delta, the Pearl River Delta, Shandong Peninsula and other areas. However, after 2004, the manufacturing enterprises began to migrate to less developed area, such as the northern Jiangsu, the middle and western Shandong and the middle and western regions in China. Enterprises that met the domestic market mainly migrated to the central and western China, while export-oriented enterprises mainly migrated from the Yangtze River Delta and the Pearl River Delta to Shandong Peninsula, Liaodong Peninsula and other areas with convenient transportation. Lastly, the eastern area showed little tendency of industrial upgrading. The development of enterprises, especially enterprises that met domestic market was still labor cost-driven. However, the development of exported-oriented enterprises showed a tendency of capital-driven.
Using complex network analysis, this study applied GIS, Pajek, Matlab and database, etc., to build the global transnational investment relationship network, and analyzed the temporal evolution of the spatial structure and network complexity of the global transnational investment network from 2001 to 2012. The results shows: 1) The global transnational investment network is showing a “core-edge” ring structure, whose inner structure is changing and reorganizing. The investment network transformed from dual-core (North America and Western Europe) structure into overlapped and related multi-core (North America, Western Europe, the Caribbean, Eastern Asia and Australia) topological structure, with capital gradually flowing from Western Europe, North America, and Eastern Asia to Northern Europe, South America, West Asia and Southeastern Asia in the macroscopic view. 2) The small-world characteristic of the investment network is prominent. The network is scale-free and shows a decrease overtime. 3) The countries that are active in the investment have higher control of the transnational investment network. The confounding factors influence the spatial reachability of the transnational investment. 4) Ranked by the complexity (dissimilarity) of the transnational investment structure, the result from high to low is terminal invest countries, regional invest countries, normal invest countries and isolated investment countries. Countries with different functional types have a clear trend of clustering.
With the development of information technology, big data has become a research focus of all sectors. There is an increasing demand for big data in the urban planning management process. Big data acquisition and calculation is a key technology in the process of the smart city construction. This article covers the following major aspects: 1) Distance table linking to urban service physical store table is used to establish spatial association frequent rules model based on the concept of spatial neighbouring point and the property of spatial point entity; the article also introduces the method and procedure of how spatial frequent items and spatial association rules appear in urban service spatial association model; 2) “For xml path” technology is used in SQL Server to build spatial transaction database because transaction database is needed in association rules computing; 3) Python+sqlite3+lxml+BeautifulSoup technology is used to crawl the online data of the companies in Nanning which have all of their public information registered on “Baidu Nuomi” (https://nn.nuomi.com/); 4) Apriori algorithm is applied to analyze spatial frequent items and spatial association rules in urban service industry of 6 distance thresholds between 10 to 1 000 meters with the obtained data. In case study, the top six registered businesses in “Baidu Nuomi” are snacks and fast food, beauty, hotels, bakeries, sweets and drinks, budget hotels. The spatial association rule of {budget hotels, hotels} has a high degree of confidence and a high upgrading degree in the distance threshold of 10 m and 50 m, being a set of strong spatial association rules. This illustrates the Nanning hotel industry has the characteristics of a compact layout, with all kinds of hotels being together. The spatial association rule of {sweet drinks, snacks and fast food} is a set of strong spatial association rules in the distance threshold of 50 m, 500 m and 1 000 m. Snacks and fast food frequency is very high, especially in the succeeding rules with high support degree. In different distance thresholds, as a kind of mass consumer entity service, snacks and fast food restaurants are distributed around various industries. Because the lift degree of these rules is about 1, the snacks and fast food industry has the characteristics of no connection with other industries. This study is an attempt to use ubiquitous web data around us to analyze city management. Researchers can get a steady flow of big data so as to better carry out the studies on city big data in real time with this methods and thoughts.
In the discipline of criminal geography, there always exists opposite theoretical views of the impact of urban built-up environment on sense of residential security. James Jocabs proposed the concept of ‘street eyes’ and appreciated its surveillance role in enhancing the sense of security, while the defensible space theory proposed by Newman regarded large flow of human traffic as public safety risk. This conflicting theoretical explanation incurred hesitation and confusion between aggregated design approach and segregated design approach. The different empirical findings and planning ideas stemmed from significant divergent built environment and social environment in various regions throughout the world. Owing to the existing research only carried out in European and American cities, it needs to be reexamined which theory has more explanatory power in Chinese context. Via Chinese General Social Survey data in the year of 2010, point of interest and road network data, this article analyzed the influence of urban built environment and its interaction role with social environment on sense of residential security in 278 Chinese urban communities through hierarchical linear modeling for the first time. This research demonstrated that mixed-used land measured by entropy index of POI functional types, compact road network measured by road density or proportion of secondary and slip road area, and high utilizing density measured by population density or POI density had a significant negative effect on sense of residential security overall. On the contrary, when built environment was relatively sparse, and had single land use and large block size, people would have a higher sense of security. It should be noted that the impact of urban built environment on sense of security is not invariable, and the ‘street eyes’ would not spontaneously play their defending roles until the community had strong cohesion, abundant social capital or homogenously composed. With the increase of community cohesion and population homogeneity, the positive role of "narrow road, dense network and open block" would gradually play on minimizing the resident’s sense of fear. However, according to the critical value in model, compact, permeable and diverse space still had negative effect on sense of security in most case communities in 2010. In other words, the theory of defense space is more applicable to most of sample communities in our country, and the function of street eyes is only played in a small number of sample communities with strong social cohesion and demographic homogeneity. To sum up, we should gradually and conditionally promote the planning work of "narrow road, dense network and open block", understand residents’ concerns about the sense of security, and avoid adopting a one-size-fits-all approach. Simultaneously, planners should combine the guiding ideology of urban design and the process of community development together in order to reach street eyes’ full potential and construct safe communities.
Traditional village as the material carrier of human culture heritage, facing space reconstruction and transformation of society in the process of rapid urbanization. Village traditional culture facing the realistic problem that lost its space carrier and space. As the basic unit of the village, home is the micro scale for geography to research the man-land relationship. Based on the geography of home, this article, which uses the basic theory and method of space syntax, locates the reconstruction of traditional villages and the home space in the context of repaid urbanization. It not only focuses on the spatial analysis of culture but also emphasizes the cultural studies of space. Following the insight into the micro space, this article reveals the cultural representation of material changes of the home space and the socio-cultural logic that hidden in the reconstruction process of space form. The findings of this article include: 1) In the process of rapid urbanization, the responses of individual families follow different logics of spatial production. Three different reconstruction patterns could be discovered in the process of the reconstruction of the home space, namely “family modernization”, “from home to household”, and “home is separated from the house”. 2) Accompanied with the reconstruction of home space, the relationship between human and nature, the sacrifice space, the internal and external relations, the kinship between family members, the intergenerational relationship, and the gender relationship have been reconstructed as well. 3) The location and the large number of immigrants are the main external driving forces while the modernization of the villagers' families and the economic needs of the home space are the internal driving forces. Both of them contribute to the reconstruction of home space in Zhucun Village. The new socio-culture relations brought by urbanization are the intrinsic logic of the reconstruction of the home space in Zhucun village. This research provide references and enlightenment for the new urbanization and the development of urban villages.
The expansion of informatization, networking and globalization makes internal communication of urban agglomeration increased sharply. Due to the powerful shaping strength of urban flows, spatial structure of urban agglomeration has suffered dramatic structure deformation. It is meaningful to identify and optimize the structure of urban agglomeration from the prospect of the urban flow. Based on economic-social data and road traffic data of the Yangtze River Delta in 2014, this article carries on a comprehensive measurement of urban flow in the Yangtze River Delta. From the prospects of “Node-contact-pattern”, we try to identify the deformation structure of the Yangtze River Delta urban agglomeration with Multidimensional Scaling Analysis. The results indicate that: 1) At the node level, there is a significant hierarchy change of urban centricity in flow space. 67 cities are divided into four levels, the number of middle level city (including level I and level II) in flow space increased dramatically in contrast to traditional rank-size distribution. 2) The connections between nodes in local districtsare restricted to the law of geographic space distance, but high level flows exist between Nanjing, Shanghai, Hangzhou and some other cities, which characterized by the trans-regional intercourse feature and “7” glyph structure in space. 3) In terms of node spatial pattern identification, Multi-dimensional Scaling Analysis can make multidimensional connection matrixreduce to two-dimensional space matrix, the result is more objective and intuitive. Flow space structure pattern shows a dramatic deformation due to the core node “concentration” and the edgenode “discrete”. On one hand, cities such as Shanghai, Hangzhou, Nanjing, and Suzhou present a group concentration, which formed a “core area” characterized by large-scale, continuous urban space, and closely connection; On the other hand, cities in the north of the Yangtze River and south of Hangzhou bay show a scattered deviating trend from the “core area”. In order to improve the efficiency and integration level of the Yangtze River Delta, urban agglomeration, economic development and transport network construction of those structural deviation cities should be noticed by both state and local governments.
The improved TOPSIS Model and GIS Spatial Analysis Method are used to study the spatial difference characteristics and influencing factors of livelihood capital in 21 prefecture-level cities in Guangdong in 2015. Results show that: 1) The comprehensive level of livelihood capital of people with disabilities is obviously characterized with “level difference”. High-livelihood capital prefecture-level cities are represented by Guangzhou, Zhaoqing and Qingyuan while middle- and low-livelihood capital prefecture-level cities are distributed dispersedly, mainly in Shaoguan in the northern Guangdong, Yunfu and Yangjiang in the western Guangdong, Chaozhou, Jieyang and Shanwei in the eastern Guangdong. The overall distribution pattern is characterized by “large disperse and small cluster”. 2) Obvious differences are shown in different types of livelihood capital levels of people with disabilities. Regions with higher financial and social capital level are mainly distributed in the northern Guangdong. Labor, rehabilitation and material capital level are highest in Guangzhou while other areas are relatively low and scattered. Five types of capital in coastal city in the eastern China and Yunfu, Maoming, Yangjiang of the western Guangdong is relatively low. 3) The total amount of livelihood capital of people with disabilities demonstrates significant spatial autocorrelation and regions with similar size tend to cluster geographically; distinctive differences are shown between hot regions and unpopular regions, with cluster distribution characteristics on the whole. Thereof, hot regions are mainly distributed in Guangzhou and Qingyuan while unpopular regions are mainly in Jieyang and Shanwei in the eastern Guangdong. Both have small coverage. The analysis finds that policy environment, economy level, education and training and rehabilitation service are all important factors that affect the spatial distribution pattern of livelihood capital of people with disabilities in Guangdong Province.
Economy, ecology, energy and education (‘Four-E’) are essential elements for promoting regional coordinated development. Construct the comprehensive evaluation index system of 4E in the Yangtze River Economic Zone, comprehensively evaluates the spatial pattern of economic development, ecological protection, energy construction and educational quality of the Yangtze River Economic Zone from 2003 to 2014, and establish the coupling coordination evaluation model, analysis the temporal and spatial evolution trend of 4E coordinated development. Results show that: In 2003, the spatial pattern of ecological protection index of the Yangtze River Economic Zone was that the midstream area higher than the downstream area higher than the upstream area. From 2003 to 2014, the ecological protection index of the downstream areas increased rapidly, upstream area of energy construction and education quality index surpassed than the midstream area. In 2014, the spatial pattern of ecological protection index was that the downstream area higher than the area midstream area higher than the upstream area, the spatial pattern of energy construction and education quality index changed into the downstream area higher than the upstream area higher than the midstream area. In 2003, the spatial pattern of 4E in Yangtze River Economic Zone was the ecological protection index higher than the economic development index higher than the energy construction index higher than the education quality index. From 2003 to 2014, the economic development index, ecological protection index, energy construction index and education quality index of the Yangtze River Economic Zone continued to rise, which the economic development index growth is most obvious, ecological protection and energy construction, education quality growth rate was basically flat. In 2014, the spatial pattern of 4E turned to economic development index higher than the ecological protection index higher than the education quality index higher than the energy construction index. From 2003 to 2014, the 4E coordination index of the Yangtze River Economic Zone showed an upward trend, the coordinated development model of 4E changed from the center gather towards equalization. At the end of this article, some suggestions are put forward, such as accelerate the transformation of traditional economy to green economy, improving the ecological carrying capacity of resources and environment, reducing the energy consumption per unit of GDP and increasing the economic transformation rate of scientific and technological achievements.
Based on the e-long hotel rates and survey data, using mathematical and spatial analysis in inverse distance weighting interpolation methods, the spatio-temporal differentiation features of Guangzhou main city 699 star hotels before and after the 117th and the 118th Canton Fair are studied. Results shows that: 1) During the fair forms three peaks, the recess forms the bottom. Overall presents “three-liter three-down” situation. In addition, the higher the star, the greater the increase. Star hotel prices did not dramatically rise on the May Day and National Day. Hotel prices on National Day rose much lower than the show. 2) Different star hotels have different hot-spots of price during the Canton fair. Hotel prices’ spatial distribution shows circle structure. It takes Pazhou as the center and shows distance attenuation law significantly. The downtown area has higher hotel prices and it increases greatly than the edge. It is higher along the metro station, shopping district, railway stations and sports center. And extend towards the south trend obviously. 3) Different factors affect different directions on hotel prices. Hotel type have an impact on hotel prices increase. The degree of convenient transportation and distance from exhibition hall affect the hotel prices directly. In addition, distance from the business district and its surrounding natural environment affect the price fluctuation. Regional development strategies and policies are the key factors that affect the hotel prices. Each of the elements intertwined with each other affects the hotel prices trend. 4) Hotel prices can be used as an important indicator to measure the impact of large exhibition on the city.
As the two elements of tourism economic system, it is of great significance to seek the balance and coordinate the relationship between tourism demand and supply. At the background of supply-side structural reform and according to the coupling coordination principal,the comprehensive evaluation index system of tourism demand and supply should be built and coupling coordination model is used to measure and evaluate the development level and relationship of tourism demand and supply of Heilongjiang Province. The research shows that: 1) From the point of view of the overall development of the tourism supply and demand system, from 2004 to 2014 the two systems of Heilongjiang Province rise in wave and the comprehensive development situation is good. The tourism demand system has low stability, high elasticity and strong restoring ability. The tourism supply system has significantly improved and the stability has highlighted. 2) From the point of view of the coupling coordination development of tourism supply and demand, from 2004 to 2014 the coupling coordination degree is steadily rising and coupling coordination level has experienced four stages: mild disorder-on the verge of disorder-barely coordination-preliminary coordination; the two systems has been from disorder to order, from the disorder to coordinate. In the tourism supply and demand type, the tourism supply lag is the historical characteristic and demand lag fade in expanding trend. 3) From the point of view of the structure of the coupling coordination development, the tourism demand and supply subsystem steadily increase and it is between barely coordination and preliminary coordination development stage. Compared with the tourism demand system, the tourism core reception subsystem give priority to develop, the tourism environment subsystem synchronously develop, the tourism service subsystem is relatively backward and the tourism transportation subsystem is badly lagged behind. Hereto, it is necessary to focus on boosting the structural reform of tourism supply side, optimize the structure of supply and improve supply efficiency for Heilongjiang Province. On the one hand, to increase the quantity of effective supply, we should not only pay attention to develop new tourism products, but also focus on making up for the lack of tourism core supply. On the other hand, to adjust the structure of tourism supply, the tourism supply focus on building the core tourism supply and environmental supply for a long time, and the supply of tourism services and transportation is seriously inadequate and become short. On the basis of supply and demand docking, according to the sequence of tourism transportation - travel services - tourism environment - tourism core reception, we need step-by-step and rhythmically to adjust the structure of tourism supply and to realize efficient development of tourism supply from the node to the whole domain, which is the stimulus "strong impetus" of tourism demand.
Urban land use in Russia experienced the transition process from the planned economy of former Soviet Union to the market economy of post-Soviet Union. This article used St. Petersburg as an example and analyzed spatial pattern of urban land use of 1948, 1987 and 2016 and its chanages. We calculated the location quotients of residential, industrial and commercial land using GIS analysis and characterized the spatial structure of urban land use based on spheres of perspective of statistical area and land use data. The results showed that residential, industrial and commercial land distribution patterns are different. 1) Three land uses in the overall spatial distribution showed a certain degree of dispersion. Among them, residential land was the most dispersed, industrial land showed subregional distribution characteristics, in contrast, commercial land showed the highest level of aggregation; 2) Commercial land was dominant in the core circle, industrial land was dominant in the old town ring, and all three land use types showed highest intermix in this area spheres, and the outer suburbs circle was still in the initial stage of development, indicating that urban landscape development in this area was not yet mature; 3) Comparing location entropy of land use of quadrant and circle type, we found three land use types in St. Petersburg showing obvious characteristics of sector structure, indicating that the main form of urban space expansion was along major transport routes, where industrial land occupied a more favorable traffic sites in urban spatial distribution, followed by residential land, with inadequate distribution of commercial land in the city center area. Urban land use distribution in St. Petersburg was affected mainly by the planned economy and the present urban land development is still in the process of suburbanization. This study explored the impact of spatial development of metropolitan land use under different systems. It may provide a reference for other metropolitans experienced similar social transformation. Formations of land use pattern of St Petersburg may have the following five mechanisms: maintaining the mainframe of the former Soviet Union land use structure ; the administrative adjustments for improving the city land use structure; housing system reform under the market economy that promoted the city residential suburbanization; relatively weak land market function in land replacement process and the role of industrial transformation; old city still being the main production center, which slowed the land use transformation.
Food is the important guarantee of the social and economic development. By taking the Henan Province agricultural data (2014-2015) as the indicator layer, this article assessed the food security in Henan Province by using standard cultivated land coefficient model, food resources carrying capacity, cultivated land pressure index model and food safety driving force model. The results showed that: 1) From 2005 to 2014, the overall cultivated land productivity increased steadily, the farmers’ enthusiasm for growing grain increased by 10% in study area, the pressure index of cultivated land decreased by 71%, the farmers’ income increased by 13%, and the gravity center of the cultivated land showed a southwest movement trend. It’s that cultivated land resource in 10 years appeared in the southwest area of cultivated land resource is higher than the northeast, the southwestern cities of cultivated land resources protection weak in northwestern region of Henan Province; 2) Between 2005 and 2009, the contribution rate of planting ratio of grain to the arable land productivity in Henan Province was 80.61%; In 2010-2014, contribution rate extreme value transferred to grain yield per unit, and its contribution rate was 100.37%; Compared with grain yield per unit area, planting ratio of grain had a leading role in improving the productivity of cultivated land in Henan Province. In addition, overall situation of cultivated land productivity will increase steadily, and cultivated land pressure coefficient and standard has obvious negative correlation between cultivated land coefficient, cultivated land pressure index space distribution in northern and eastern pressure is low, cultivated land pressure decrease gradually from west to east; 3) Fertilizer input, the farmers' enthusiasm for growing grain and protection ability of cultivated land had a strong coupling relationship with food security; However, the farmers’ enthusiasm for growing grain and protection ability of cultivated land presented a negative correlation. High cultivated land pressure index of Zhengzhou and Sanmenxia is the result of social and economic elements and natural geographical environment. In terms of Zhengzhou, the limited urban area within the scope of regional economic development, get more economic benefit, is the important foothold of its development. In terms of unit efficiency, the unit of second and third industry output value is much higher than the first industry, cultivated land become one of main way to obtain higher economic benefits. The behavior of lead to Zhengzhou City since 2005 cultivated land pressure index is high, and the food security situation showed a trend of deterioration.
This article achieved the extraction of land use and land cover change information of the Daling River Basin from 1986 to 2014 (7 periods) based on Landsat remote sensing image. It was found that land use change has a negative effect on climate by analyzing climate change (13 periods). The results showed that: 1) Construction land and farming-forest land expanded obviously, the area increased respectively by 322.30 km2 and 1 504.94 km2 accompanying by waters and beach and other unused land shrunk significantly, the area decreased respectively by 102.42 km2 and 1 724.61 km2; 2) Land use of Daling River Basin lead to average annual rainfall, average relative humidity and average wind speed minor decreasing, decreased respectively by 14.94 mm, 0.2% and 0.04 m/s; average temperature rising slowly, increased by 0.1℃; 3) Policies of returning farmland to forest and grassland and establishing basin reserve management can increase vegetation and water coverage area, thus relieve temperature rise brought by urban heat island effect and improve the quality of ecological environment in the Daling River Basin.
Precipitation is a significant part of the hydrological cycle and so the investigation of changes in precipitation characteristics is normally the first step in investigating the impact of climate change on water availability. However, high-resolution precipitation datasets are seldom available, which, to some extend, limits our understanding of spatio-temporal patterns in precipitation regies and basin scale hydrology. Since regions around the globe with sufficient precipitation gauge networks that are up to the challenge of this type of research are few and far between, precipitation estimations from space borne sensors are often applied to supplement the information collected from existing low-resolution precipitation gauge networks in near real-time applications. Based on observed daily precipitation data as “real data” from 42 stations covering a period of 2001-2010 in the Inner Mongolia, China, TRMM (Tropical Rainfall Measuring Mission) precipitation data with spatial resolution of 0.25°×0.25° was downscaled based on statistical relations between NDVI, meteorological variables, and DEM using LOO (Leave-One-Out) cross evaluation method, spatial autocorrelation analysis methods. The lag time between NDVI and precipitation changes was also considered in this study. The results indicated that: 1) On annual scale, TRMM data can be used for estimation of annual precipitation amount in the Inner Mongolia Region and linear relations can be identified between annual TRMM and observed precipitation data; 2) The analysis of the effect of lagging on the vegetation response to precipitation indicates that a period of 10 days accurately is the lag time, showing the relatively rapid vegetation response to precipitation. Moran’s I indicates that the vegetation index is spatially correlated and identified spatial heterogeneity in the transitional zones between different types of land use and land cover and the unused land area; 3) Significant relations between TRMM and observed precipitation can be detected at moderate spatial scale with spatial resolution of 0.50°×0.50°; 4) Temperature is found to be an important factor influencing downscaling of TRMM precipitation data due to high sensitivity of NDVI changes to temperature variations in the Inner Mongolia Region. Inner Mongolia is topographically levelling and hence DEM is not the significant factor having impacts on downscaled TRMM data; 5) Downscaled TRMM can well reflect spatial patterns of annual precipitation changes. Less precipitation can be found in west Inner Mongolia and more precipitation in south and southeast Inner Mongolia. This study provides another possibility in evaluation of spatial patterns of precipitation changes, and hence provides and right precipitation dataset for conservation of grassland and also irrigation management in the highly eco-environmentally fragile region.
Research the change of potential evapotranspiration and its sensitivity, it is of great significance for agricultural sustainable development and protection of the ecological environment. This article use Penman-Monteith method and sensitivity coefficient method to analyze spatial and temporal variation of potential evapotranspiration and sensitivity of potential evapotranspiration to average temperature, wind speed, solar radiation, and vapor pressure from 1965 to 2014 in Liaoning Province. It aimed to investigate the dominant factors affecting the potential evapotranspiration and the quantitative response of potential evapotranspiration to climate change. The results showed that: Nearly 50 years potential evapotranspiration showed a significant decrease trend. In space, it presented by the west to east decreasing trend. The reference evapotranspiration was most sensitive to vapor pressure, which is followed by solar radiation and wind speed, average temperature on an annual scale. In terms of season, average temperature was the least sensitive variable in spring and autumn, wind speed was the least sensitive variable in summer and solar radiation was the least sensitive variable in winter. Spatially speaking, spatial variation of meteorological factors and its sensitivity coefficient are consistent during the year. Sensitivity to the temperature of the potential evaporation is increasing north to the south, sensitivity to the vapor pressure and solar radiation of the potential evaporation is decreasing east to west, but the change of wind speed is opposite. The main reasons for the decrease of potential evapotranspiration in Liaoning Province are the significant decrease of wind speed, and the decrease of solar radiation and the increase of vapor pressure also contribution to the decrease of potential evapotranspiration.
Multi-scale variability characteristics of ocean surface wind direction and speed from 1950 to 2011 are studied based on NCEP/NCAR reanalysis data. Sea surface wind field shows the seasonal characteristics. Results show that: in past 62 years, large area of wind direction in the Bohai Sea tend to be from northwest to northwest northand wind speed is the most in winter;wind direction tend to be from southeast to easterly winds and wind speed is the lest in summer; wind speed has started to decreased since 1970s and reduced significantly in winter. Wavelet analysis and cross-spectral analyzing are used to observe wind direction and speed on the Bohai Sea over the last 62 years. The characteristics of ocean surface wind direction and speed in the Bohai Sea show periodic oscillation at inter-annual and decadal scale. The main periods of wind direction are 1-year, 8.7-year, 15.8-year; whereas the main periods of wind speed are 1-year, 6.3-year, 15-year. The significant resonance periods between wind direction and speed are observed at the following temporal scales: 2.67-year, 5.71-year, 20-year. The resonance periods have relationship with variability of East-Asian Monsoon and Western Pacific Subtropical High.
Based on the DRASTICH model of groundwater vulnerability assessment, the uncertainty characteristics of each parameter were analyzed, and the stochastic simulation method was used to simulate both random parameters and fuzzy parameters. By setting the confidence level of the fuzzy parameters and the percentile of the vulnerability index, we obtain the confidence interval of the multiple groundwater vulnerability. On this basis, the soft zoning distribution of the groundwater vulnerability was plotted according to the expectation vulnerability index of upper limit fuzzy interval and the lower limit fuzzy interval. The results showed that: 1) The evaluation results of groundwater vulnerability in the form of the confidence interval can reflect the objective reality of the groundwater vulnerability under the influence of various uncertain factors, and provide more reliability than the conventional method; 2) The soft zoning distribution of groundwater vulnerability map, which preserves the fact that uncertainty is objective, can give decision maker more reference information; 3) The soft zoning distribution of groundwater vulnerability showed: the degree of vulnerability of the conservative distribution of the overall higher than the risk distribution, the higher the confidence level selection, adventure distribution and conservative distribution of the spatial distribution of the difference, and with the maximum possible; 4) The distribution of groundwater vulnerability in the study area was spatial agglomeration, high groundwater vulnerability areas were generally concentrated in the middle and the southern region of the lower Liaohe River Plain, low groundwater vulnerability areas were generally distributed in both east and west sides of the lower Liaohe River Plain.
