The ideology of main functional areas is a dominant regional development theory. In the framework of the new theory, the industrial structure evolution path and the new inter-regional coordination mode are key problems that should be focused on. Based on a self-developed inter-province multi-regional dynamic CGE model , this article classifies the regions oriented to the main functional areas, and simulates 3 regional industry policy scenarios. Those scenarios are called 'white scenario', 'yellow scenario' and 'blue scenario' respectively. The 'white scenario' is a baseline scenario for contrast, and economic system runs without external disturbance. In the 'yellow scenario', investment of the finance, insurance and service industry in the optimized development area are increased, which represents a tendency of preferential policies on the optimized development area. In the 'blue scenario', investment of the construction, delivery of warehousing, wholesale and retail, and real estate in the key development areas are increased, which represents a tendency of preferential policies on the key development area. Scenarios' simulations show that the competition among main functional areas always reflect in the competition between optimized development zone and key development zone, and the natural regional convergence force is not enough to narrow regional disparities, so more tough regional regulate policies is needed. The natural evolution of regional industrial structure would induce "automatic" CO2 reduction, which deduct a more rigorous judgment for CO2 reduction policies. In the current development trend, China's regional gap is narrowing. However, once the policies of the main functional areas run, regional economic gaps would be wide again. Moreover, financial policy priorities in optimize the development area would lead to a wider regional gap, which is the most conducive policy to promote overall economic growth on the other hand. How to get more knowledge about regional coordination and regional management needs further research.
Based on the central place theory proposed by Walter Christaller, taking the shortest time and weighted average travel time as the accessibility evaluation index, using the accessibility calculation module as technical support based on the GIS platform, the spatial evolution and reconstruction of the central place system are explored from the aspects of spatial accessibility, spatial interactions, spatial scope of services under homogeneous background and transportation background. Through this way, formation process simulation and spatial expression of central place system are probed preliminary. The result shows that: Firstly, the secondary central place appears in the area which accessibility time is longest to the superior center under homogeneous background. Under the assumption of homogeneous plain, traffic in any direction are the same. The central place appears in the center of the hexagonal market area which accessibility is best and then present the concentric circles diffusion. With this diffusion, the time to the central place get longer. The secondary central places appear in the six vertices of hexagon whose accessibility time is the longest. And so on, the low level central place continue to appear until the production of the central place with the lowest level. Secondly, the accessibility based on weighted average travel time in the same level central place is not same. For same level central places, the closer to the high grade center place, the weighted average travel time is shorter. The same grade central place emerge the differences in growth. The closer to the high grade central place, the growth faster. With the increase of the grade and the quantity of central place, the difference of accessibility and centrality become more and more. As a result, continuous grade central places are formed. With the emergence of transit lines which connect central place, the accessibility of each grade central place is greatly raise. And the “Pole＆Axis System” is formed gradually. Finally, the spatial structure of central place system gets into a comprehensive organizational equilibrium stage which is composed of point, axis and network along with the traffic network evolution.
Based on the cross-city cooperation-patent application data, intensive research has been carried on the cross-region innovation cooperation in China（excluding Hong Kong, Marco and Taiwan）. A new concept, innovation radiation distance, is raised and the corresponding calculation method is also introduced and applied on the selected samples to find out the radiation distances for each city and each industry. The results show that the innovation radiation distance has a negative correlation relationship with the geographic distance and no apparent evidence of positive impact from the information flow amount can be identified either. Nevertheless, the radiation transmission is not universal to all directions and some areas on the radiation periphery feel feeble impact. Moreover, different industries cannot be described by an overall radiation distance rule. The outcomes can be summarized as below:1)The innovation radiation distance does not grow proportionally with the patent amount. For instance, some cities, like Shenzhen and Chongqing, tend to find partners far away, though their cooperation-patent is relatively small. However, some other candidates say Shanghai and Hangzhou, are vice versus.2) The innovation radiation distance cannot be determined by the information flow alone. Some cities show greater incentives of cross-city innovation cooperation through frequent exchange and propagation of technology and knowledge, while other cities display a prominent regional confinement in information communication, which implies a huge potential for further improvement.3) Through the study of innovation radiation distance and range in eight factors on the selected sample, the article find out that Beijing has a profound radiation effect over the whole country, which is unparalleled for other competitors, though the equality of radiation should be attached more attention by putting more weight to the western region. Three cities, Shanghai, Nanjing and Hangzhou, constrain themselves to the pan-Changjiang River delta region and show infinitesimal impact on other regions. By contrast, Xi′an, Chongqing, Chengdu, Wuhan and Changsha have the tendency of cooperation with eastern developed region. More collaboration with the under-developed regions should be encouraged.4) The study in four sectors, electronic engineering, instrumentation industry, chemical industry, and mechanical engineering shows that the innovation radiation distance is not proportional to the cross-border collaborative patent application amounts. The electronic engineering industry in Chongqing, instrument manufacture in Shenzhen and mechanical engineering industry in Xiamen, Chongqing, Shenzhen, Chengdu, Beijing and Changsha tend to plunge into long-distance cross-border cooperation though the collaboration in patent application is insufficient.
At present, the ways and means to solve environmental problems have developed from environmental control, environmental management to regional environmental management. Regional environmental management is an important part of regional management, but it is different from the general environmental management, PRED (population, resources, environment and development) is the core of modern management development, at the same time, we need to carry out the management of population, resources and environment management. Environmental management more and more emphasises on different types of regional environmental management, such as the urban environmental management and rural environmental management. Regional environmental management is the union of regional sustainable development and environment management, it is oriented towards an economy closely, with common environmental problems and collaborative management. The scale is an important part of regional management in the regional environmental management. Scale is a comprehensive concept to ascertain space-time positions and levels. Regional environmental management scale has a macro-medium-micro-scale level. The medium-scale serves as a connecting link between the macro and micro, which includes interregional, regional and sub-regional environmental management. Based on the understandings, this article analyzes the important role of scale in regional environmental management, discusses the basis for confirming the range and expounds the necessity, characteristics and level of mosaicism as well as patterns’ innovation from the medium-scale of environmental management. The above content theoretically expands and enriches the geography’s important role in this field, and it also has important guidance for the construction of environment management system and environment-friendly society in practice.
Research on the mechanisms of urban land expansion in metropolitan areas is of significant importance for effective regulation and control of urban land utilization and layout. Based on income maximization theory, this article develops an analytical framework to distinguish the cost- and benefit-related factors of urban land expansion. Cost-related factors of urban land expansion include the proportion of cultivated land and water area, elevation, slope, the proportion of geological-hazard-prone area and key ecological function area, and the proportion of planned construction area. While benefit-related factors include the proportion of construction land area in base year, the distance to central business district, sub-central business district, industrial centers, Entry/Exit points of expressway, railway station, international airport, main port and the nearest grid in which the proportion of construction land is 100%, and the number of neighboring grids in which construction land is the main land use type. Taking Nanjing, a large city located in the Changjiang River Delta of China, as an example, using remote sensing data in 1995, 2001 and 2007 at the scale of 1 km×1 km grid, this study examined the spatial determinants of urban land expansion over the periods of 1995-2001 and 2001-2007. The spatial error model is also applied to taking spatial autocorrelation into account. Results indicate that the benefit-related factors, such as the proportion of construction land area in base year in the grid, the number of neighboring grids in which construction land is the main land use type, the distances to central business district, industrial centers, Entry/Exit points of expressway and so on, and the cost-related factors, such as the proportions of cultivated land, water area, geological-hazard-prone area, key ecological function area, and planned construction area in the grid as well as the slope are the major spatial determinants of urban expansion in Nanjing City. Comparing the magnitudes of factors in two sub-periods, it is found that the benefit-related factors such as accessibility (the distances to central business district, industrial centers, etc) and agglomeration (the nearest grid in which the proportion of construction land is 100%) have greater impacts than the cost-related factors like physical conditions (elevation, slope, etc.) and policy constraints (key ecological function area and the proportion of planned construction area). We also highlight the importance of globalization and marketization as the crucial socio-economic drivers of urban land expansion in Nanjing. Spatial policies such as urban planning and ecological planning have become increasingly important in recent years for constraints of urban land expansion. The article also summarizes policy implications for the location choice of prime farmland in large Chinese cities.
The geopolitical setting study is the second attempt to revive the political geography of the geographical circles, also it reflects the political geography studied from a single element to multiple elements and integrated development. Based on the two “geopolitical setting” international seminar which held in Beijing and the early geographical environment research, the geo-setting is defined which contains geographical environment, geographical relations and geographical structure in this article. Geographical environment is consist of the natural environment, economic and population environment, and the social and cultural environment. Geopolitical relations includes economic relations, political and military relations, and social and cultural environment. The geographical structure contains political military structure, economic structure and space structure. And then, the article uses a combination of AHP decision-making analysis and fuzzy comprehensive evaluation method to evaluate the geo-setting of South Asia quantitatively. The results show that: In South Asia there exists significant space divided differences in the geographical environment, geopolitical relations and geo-structures, which eventually led to the geo-setting in South Asia can be divided into four categories, India for a class, Pakistan and Bangladesh for a class, Bhutan and Nepal for a class, Sri Lanka and Maldives as a class. There are three reasons which caused this spatial differentiation, which are geographic determinism, interdependence theory and institutional theory.
The impact of transportation on accessibility of cross-border scenic area is an important aspect of research on cross-border tourism region. In this article, we focus on cross-border tourism region in Dabieshan Mountain. Through constructing regional internal accessibility, regional external accessibility, analyzing quantitative accessibility of scenic area of cross-border tourism region in Dabieshan Mountain with GIS software, and generating spatial structure schematic drawing, we arrive some conclusions that: 1) Highway plays a crucial role in improving internal global accessibility, but the impacts of ordinary railway and high speed railway on accessibility are not obvious. 2) As far as single transportation way is concerned, the impacts of high speed railway, ordinary railway and highway on improving internal local accessibility are limited. This is due to the characteristics of shielding of them and the limited quantity of entrance and exit of railway station and highway, which also make them not to become universal transportation so far. 3) By measuring boundary effect, we find that the shielding effect of administrative boundaries on low-rank transportation infrastructure is better than that on high-rank traffic facilities. 4) The impact of universality transportation way on external global accessibility is weak, and the effect of ordinary railway and highway on improving global accessibility is greater than the effect of high speed railway. Combined with data from the survey, this article holds that: although highway is not universal traffic way in the case area at present, regional external accessibility of the whole cross-border tourism region in Dabieshan Mountain will be improved based on the continuous construction of highway network, and highway also will gradually become a ubiquitous transportation way. 5) The impact of high-grade traffic facilities are mainly embodied in regional external accessibility. Taking typical cross-border scenic area—Tiantangzhai as an example, by measuring border effect of cross-border scenic area based on construction of time accessibility non-line coefficient, and drawing spatial differentiation figure of accessibility of scenic area, this article finds out: distribution structure of administrative areas on both sides of cross-border scenic area present significant symmetric pattern——with provincial boundaries for axis, cross-border scenic area for the symmetric point, from county administrative region to prefectural-level city, to the capital city, and the higher administration rank, the smaller time accessibility non-line coefficient, the stronger the impact of high-grade traffic facilities. It shows that the shielding effect of boundary on transportation infrastructure exists in cross-border scenic area, and action effect follows the distance attenuation law, which presents significant administrative areas symmetrical pattern. Accessibility of scenic area can reveal border effect of boundary on transportation infrastructure, prove accessibility is a kind of effective method of measuring border effect, and provide a new perspective for the study on cross-border tourism region integration. In order to break the shielding effect of boundary on transportation infrastructure, firstly we should promote the construction integration of cross-border low-rank transportation infrastructure, including state roads, provincial roads, county roads, which make the provincial fringe area traffic facilities be shared, and then improve accessibility of scenic area, transfer shielding effect into intermediary effect in certain extent. Therefore, it is necessary to coordinate traffic infrastructure construction planning and investment distribution relationship about transportation infrastructure in cross-border tourism region. The integration and share of the transportation infrastructure construction must be a common key strategic of cross-border tourism region to implement.
The process of emerging and developing in Chinese Excellent Tourism City is the process of macroscopic management and organization of tourism cities and its infrastructure spatial effect is also going hand in hand with the process of China's modern tourism development and China's city construction. In the past 20 years, theoretical exploration and practice construction have made great progress though there are also some problems in the spatial distribution and its spatial effect of the transport accessibility. In this article, regional differences of the spatial distribution and its transport accessibility in 1 hour, 2 hours, 3 hours of the Chinese Excellent Tourism Cities were compared with the ArcGIS spatial orientation and spatial analysis technology. And the results showed that: the regional differences of transport accessibility of Chinese Excellent Tourism Cities have a high degree of consistency to the nationwide spatial distribution differences. Firstly, there are a large number of Chinese Excellent Tourism Cities in the eastern of China while a little in the western, the number of Chinese Excellent Tourism Cities in different provinces is quite different, and the regional difference in different prefecture level cities can be subdivided into 3 kinds of region. Secondly, there are also a great many of differences in the spatial distribution of transport accessibility of the Chinese Excellent Tourism Cities all over the whole country, and the regional economic which based on the spatial distribution also has the same character. From the Heihe City in Heilongjiang Province to the Dali City in Yunnan Province, there can be a line of demarcation of spatial distribution for 3 hours accessed area between the eastern of China and the western. In the southeast coastal area, the Huanghuai area and the JiangHuai River Basin of China,such as Henan Province, Jiangsu Province, Zhejiang Province, Liaoning Province, Hainan Province ,the 1 hour accessed area can be a big advantage for the development of the tourism. While, in the southwestern and northwestern of China, such as Qinghai Province, Xizang Autonomous Region, Yunnan Province and Inner Mongolia, the 3 hours accessed area may be the disadvantage in opposite, just because of the interaction of many factors of regional difference, such as the topography condition, urban terrain settlement distribution, the construction of urban transportation infrastructure facilities and so on. Thirdly, the law of distance decay of tourist market and tourism development potential appear vividly around 1 hour,2 hours, 3 hours accessed area of 339 Chinese Excellent Tourism Cities. And the development and construction of the Chinese excellent tourism city should be further improved.
In the Oxford English Dictionary, nostalgia means sentimental yearning for a period of the past; regretful or wistful memory of an earlier time; and severe homesickness. That is to say, nostalgia has the meaning of desire to back home. As the longing (Gr. algia) for home (nostos), nostalgia is defined as the longing for a home that no longer exists or never existed. This feeling of loss and fantastical romance was identified in the seventeenth century as a curable disease, yet by the late 20th century it had become the incurable modern condition. Nostalgia is also shown to be spatial in its expressions as well as causes, and must be investigated using a ‘dual archeology of memory and place, and a dual history of illusions and actual places’. In addition, nostalgia are both restorative and reflective, and thus aimed to both conquer and shatter space. The emergence of nostalgia is associated with various acts of spatio-temporal distanciation, from the regulation of nation-states to globalization. The locations which can call for the nostalgic motions are not only the so-called hometown, but also the places where are full of our memories of some special times, such as our campus. Therefore, the campus can be made as a kind of nostalgic space. In order to explore the nostalgic environment on the campus and discuss its spatiality, this article regards nostalgia as a spatial issue, selected Sun Yat-sen University as the study case, and its alumnus as the research objects, to describe alumnus image of Sun Yat-sen University and their construction of nostalgic space. The methodologies using to collect data are in-depth interviews and image map drawing, and the analysis method is text analysis. For doing so, we interviewed 27 alumnus and collected 35 image maps, and encoded these data. The results include: 1) For the alumnus, their nostalgic images can be divided into indicated nostalgic and evaluated nostalgic images, which are shaped by their individual and collective memories, and are influenced by the real environment of the campus, the different living experiences and daily routes in the past, graduation time and genders of these alumnus; 2) The spatiality of the campus are constructed by alumnus’ nostalgic images, and can be divided into 3 intertwined dimensions: the space as a container, power space and emotional space. However, the spatiality is internal contradictory, and becomes the unity of restorative and reflective nostalgias. These results can prove and compensate the nostalgic research on the human geography perspective, and the theories about space. In addition, the results can provide the suggestion to the utility of alumni resources and formulation of alumni policies. We hope that the coming research can use other kinds of objects to explore how to construct the nostalgic spaces.
The satellite-measured DMSP/OLS nighttime light data was widely used for regional level mapping of socioeconomic activities due to its high temporal resolution, free availability and wide swath. However, the use of DMSP/OLS nighttime light data as covariates for mapping socioeconomic activities faces numbers of problems. One of these is the spatial resolution of the available data. Although the DMSP/OLS sensor has a nominal resolution of 1 km, this has been resampled from the 2.7 km native resolution of the sensor. The second difficulty is caused by “overglow” due to surface reflection and scattering and refraction in the atmosphere which results in the overestimation of lighted areas. The third problem relates to low radiometric resolution of 6 bits (i. e. the digital number value ranges from 0 and 63) which results in data saturation over brightly light built-up areas. Vegetation indexes like NDVI are negatively correlated with the impervious surfaces and can be used for estimation of built-up areas. The incorporation of NDVI can reduce the errors occurring in estimating built-up areas from the DMSP/OLS nighttime light imagery due to data saturation and other factors. In present study, the DMSP/OLS nighttime light data was combined with SPOT NDVI data to develop an index called human settlement index (HSI), which estimated the fraction of built-up area on a per pixel basis. Due to the complementary characteristics between DMSP/OLS data and NDVI, the resultant HSI image conveys more information than both the individual datasets. The model for electricity consumption estimation was developed based on the significant correlation between the HSI and electricity consumption in Zhejiang Province in the article. Preliminary modeling results show general overestimation of electricity consumption, especially in high altitude area in southwest Zhejiang Province. The HSI was further corrected by thresholding method to overcome the overglow effect and elevation effect correction was also conducted. The modified HSI image was then used for mapping the electricity consumption in 2010 in Zhejiang Province at a resolution of 1 km×1 km. The results show that the correction of HSI results in a significant increase in accuracy in mapping the electricity consumption. The mean relative error is 26% when modified HSI was used to estimated the electricity consumption of Zhejiang province, which is much smaller than previous studies. The spatial distribution of electricity consumption is well in line with the economic development level. In addition, more than 75% of the electricity consumption located in area below 50 m in Zhejiang Province. The present research provides an integrated approach for rapid and accurate estimation of electricity consumption in regional scale on a per pixel-basis, which can be very useful for mapping socioeconomic activities from medium coarse resolution data at regional level within limited time and minimal cost.
In this article, 40 typical watershed in Guizhou Province were selected as the sample areas to build the soil roughness index (SRI) ,soil water body index (SWBI) and soil relative humidity (SRH) according to the spectral characteristics. The remote sensing information of soil type, soil relative coverage, soil relative roughness, and soil relative humidity were extracted using the object-oriented classification techniques. From the relationship perspective between the soil-system structure and function, firstly, the influences of the soil water-storage space of the single-factor and the generating-newly soil water-storage space of two-factor coupled of the single factor on the watershed-storage capacity were analyzed, and the fitted models between the single-factors, two-factors coupled and runoff depths were build up respectively. Secondly, the impacts of the generating-newly soil water-storage space of the double factors coupled, three factors coupled and four factors coupled on the watershed-storage capacity were analyzed, and the fitted models between the single factor, multi-factors coupled and runoff depths respectively were build up. Studies have shown that: 1)The soil water-storage space is a comprehensive reflection of the basin water-storage capacity, affected deeply by the soil type, soil coverage, soil roughness and soil moisture content. 2) The descending order of the influences of the four factors on wartershed hydrological droughts is the soil relatively roughness (R=0.968)>soil relative coverage (R=0.56)>soil relative humidity (R=0.558)>soil type (R=0.464). 3) Whether the double factors coupled, or three factors coupled and four factors coupled ,the influences of the coupled generating-newly factors on wartershed hydrological droughts are particularly significant, and be fitted by a linear model.
Since the Northeast China is an important commodity grain base, the persistent drought events become a serious threat to food production in this area. Now the loss of grain caused by the drought is up to or even more than 10 billion YUAN each year. Due to the significant decrease of river runoff in the periods of drought and the over-exploitation of the groundwater, the situation of gradual deterioration of ecological environment in Northeast China has happened, the drought become a serious challenge in sustainable development of social economic and ecological environment. The study of the cause and its risk assessment of drought in Northeast China are of very important for the reduction of losses in drought disaster, and also important for providing scientific and technological support in the fight against droughts. Based on the daily mean temperature and precipitation data in Northeast China , and considering the influence of summer precipitation on food production, a summer drought index is defined by the use of K index, the space-time variation of summer drought is then investigated. The summer precipitation variation coefficient, the risk index and the risk probability of summer drought are calculated and analyzed. The comprehensive risk index is defined based on four indicators, i.e. the variation coefficient of summer precipitation, the frequency of summer drought, the risk index and risk probability of summer drought, the comprehensive risk division of summer drought is also conducted. Results show that: summer drought in Northeast China is more serious in the west than that in the east. The summer drought in Northeast China is get into the frequently-occurring stage since the 1990′s.The southwest of Heilongjiang Province, the west of Jilin Province and the west of Liaoning Province are the driest regions and they are the high-risk areas of summer drought, the north and east parts of Heilongjiang Province, the central of Jilin and Liaoning Province are the lower risks areas of summer drought, the south-central of Heilongjiang Province, the east of Jilin Province and the southeast of Liaoning Province are the low risk areas. Defensive measures should be taken in the high-risk and the higher risk areas, by promoting the agricultural drought resistant technology vigorously, taking grater efforts on the climate prediction, strengthing the construction of drought resistance so as to reduce the summer drought loss in Northeast China.
：Soli wind erosion, one of the major causes of environmental problems such as farmland degradation and desertification, producing large scale of sandstorm, polluting the environment and harming human beings′ health in arid and semi-arid regions, is the detachment, entrainment, transport deposition of soil particles caused by wind. It is also a serious socio-economic issue which limits the development in those ecologically fragile areas. In the previous studies, methods for accessing wind erosion are based on land use information. In this article, however, another approach that uses GIS and T-S fuzzy neural network model to access soil wind erosion risk is presented. The approach is applied to a case study of the Yulin City located on the wind-sand transition regions of Mu Us sandy land, Inner Mongolian plateau and loess plateau, northwest China, where most serious expansion of desertification is proceeding. Environmental elements of soil wind erosion were selected and their spatial distribution data were extracted using GIS technology and T-S fuzzy neural network model was constructed after training the sample data of different wind erosion risk level. The model was applied to mapping wind erosion risk after inputting the extracted date. The entire jobs were based on the software of ArcGIS9.3 and MATLAB. The results show that: Firstly, the comparison of the risk assessment with land use information in Yulin City demonstrates that the result is in conformity with actual conditions. T-S fuzzy neural network model can reveal the relationship between risk of soil wind erosion and its environment effectively, and provide the basis for predicting wind erosion. Secondly, environmental elements such as wind energy, vegetation coverage, temperature, precipitation, topography control the distribution properties of wind erosion risk in Yulin City. Thirdly, there are 4 divisions of wind erosion risk in Yulin City: the severe risk level, the intense risk level, the moderate risk level and the slight risk level, and the area of different risk level are 4 810 km2, 5 824 km2, 13 239 km2 and 19 234.88 km2. Finally, the distribution of soil wind erosion risk is decreasing gradually from southeast to northeast in Yulin City. Moreover, the assessment of wind erosion risk and its distribution has significant meaning to control desertification and develop economic in wind-sand transition regions.
：The grain size of sediment is an important tool for the extraction of paleo-climate and paleo-environment change information. This article attempts to study the influence of sample pretreatment methods on particle size analysis result. Loess and paleosol sample were chosen from the Qianfangcun profile in the upper reaches of the Hanjiang river valley as the representative material. They are measured using a laser particle analyzer (LS1320) made by Beckman Company, U.S.A. These samples were performed using 6 different pretreatment methods before their grain-size distribution were measured, respectively. The experimental results show that the pretreatment methods and steps for the grain size measurement procedures have certainly influenced on results of grain- size distribution. Different samples should be used different retreatment methods and steps. In the process of sample pretreatment, ultrasonic vibration and oscillation time significantly influence the results of particle size measurement. Aiming at samples from the upper reaches of the Hanjiang river valley, pretreatment method A（0.8 g sample put into 500 mL beaker, then to pour 10 mL10% H2O2 and 10 mL 10% hydrochloric acid in the beaker, respectively. The beaker is filled with distilled water and static for 72 h, slow pumping to distilled water, putting into 5 mL 0.05 mol/L dispersing agent((NaPO3)6, then to measure particle size using a laser particle analyzer) is more suitable to weak cementation sediment samples, such as loess, modern topsoil and river sediments et al. Using pretreatment method A could obtain better effect of the particle size measurement because its particles can be sufficiently dispersed. The caking property of paleosol sample in the Hanjiang River valley is very high because of its strong pedogenesis. It is difficult to be completely dispersed particles of paleosol because of closely cemented between particles. There exists great differences in grain-size distribution of the palaeosol sample while it was pretreated by the pretreatment method A, B, C, D, E and F（ Method B: In the method based on A, then ultrasonic vibration with 10 min. Method C: 0.8 g sample was put into 500 mL beaker, then to pour 10 mL10% H2O2 and 10 mL 10% hydrochloric acid in the beaker, respectively. The beaker is filled with distilled water and static for 72 h, slow pumping to distilled water, putting into 5 mL 0.05 mol/L dispersing agent( (NaPO3)6), at the same time with using ultrasonic vibration 20 min, then to measure particle size using a laser particle analyzer. Method D: The samples were digested with H2O2 and hydrochloric acid, beaker was filled with distilled water and static for 72 h, putting into 10 mL 0.05 mol/L dispersing agent((NaPO3)6), then ultrasonic vibration with 20 min. Method E: The samples were digested with H2O2 and hydrochloric acid, stirring 15 min, beaker was filled with distilled water and static for 72 h, putting into 10 mL dispersant, ultrasonic vibration with 20 min. Method F: The samples were digested with H2O2 and hydrochloric acid, stirring 30 min, beaker was filled with distilled water and static for 72 h, plus 10 mL dispersant, ultrasonic vibration with 20 min）, respectively. The experimental results show that differences of the grain-size index such as the average particle size can be several times fluctuation. The pretreatment method C is more suitable for palaeosol samples from the Hanjing river valley. Dispersion effect of the pretreatment method C for palaeosol sample is better than those of other pretreatment method, including method A, B, D, E and F.
In order to find out the recharge condition in deep aquifers in the concealed type colliery in the north of China, taking Renlou colliery and the local Linhuan coal-mining district for example, hydrochemical systemic cluster analysis and hydrogen and oxygen isotopes tracing were carried out to discuss and analyze the recharge sources and its changing mechanism in the deep aquifers under the influence of mining activities. The deep groundwater of the coal-mining district was composed of direct but nonuniform infiltration and retention infiltration of precipitation and ancient underground water. In the case of TDS of deep groundwater at less than 1 000 mg/L, the δ values of stable hydrogen (D) and oxygen isotopes (18O) decreased with the increase of TDS in the coal-mining district. However, in the case of TDS of deep groundwater at higher than 1 000 mg/L, the δ values were around the average ones. In addition, the average δ values of D and 18O were -67.4‰ and -8.68‰ respectively, being relatively small compared with that of precipitation in the coal-mining district. Without the influence of mining activities, the deep groundwater of the coal-mining district was formed by the direct but nonuniform infiltration of precipitation. However, under the influence of mining activities, the deep groundwater of the coal-mining district was formed by the retention infiltration of precipitation, because mining activities had broken the original circulation condition of deep groundwater and the hydraulic alternate had been accelerated in the recharge area.
According to the field survey, flood irrigation is usually used to wash salt in crop growth period (summer) and in autumn in the study area. However, it is washing salt that leads to soil secondary salinization and waste of water resources, due to the lack of technical guidance. This article makes a comparative analysis on time series variation of soil water and salt under different irrigation (6 800 m3/hm2, 5 200 m3/hm2, 4 400 m3/hm2, 3 600 m3/hm2, 2 800 m3/hm2, 2 000 m3/hm2, 1 200 m3/hm2 and 0 m3/hm2) in Qitai county, Xinjiang Province. The results show that soil profile is at washing salt period after irrigation 1-8 days and soil washing rate is proportional to irrigation volume; after irrigation 8-45 days, soil profile is at salt accumulation period and the relationship between salification rate of shallow soil and irrigation is exponential while there is linear relationship between salification rate of deeper soil and irrigation. After irrigation 1-18 days, soil alkalization is significant and alkalization degree is proportional to irrigation volume. After irrigation 18-45 days, soil alkalization decreases basically. Under 1 200-6 800 m3/hm2 irrigation amount, the depth of soil wash salt in 60-80 cm and the depth of soil accumulate salt in 140-260 cm. To realize water utilization and washing salt more efficiently and low alkalization, the irrigation volume in the study area is 3 600-4 400 m3/hm2 in the peak irrigation period (July to August).
