The article widely gathers the information on hail disasters from many sources in China, such as weather bureau, government gencies of disaster reduction, and reports from news media According to the characteristics of report on hail disasters , the main statistical unit of hail disaster is "county" or "province" So we choose "county" as the basic unit for mapping and analysis Based on these cases, the integrated databases of hail disasters in China were established The spatial patterns of hail disasters in China were set up by the function of GIS The article expounds the spatial patterns of three different sources Concerning the characteristics of data source, the similarities and differences of the established patterns were discussed The differences of the three patterns are observable,meanwhile the differences prove themselves the differences of data sources and the data characteristics The similarities show the common laws in the spatial patterns of hail disasters in China We epitome the spatial patterns as one region, two strips, seven centers One region means the area of high-risk hail disasters covering eastern part of Qinghai-Tibet Plateau, southern part of Yanshan Mountains, and to the north of Changjiang River Two strips mean the following two regions: one is the outer margin of the first topographic step , especially the eastern part; the other is the eastern margin and the eastern part of the second step Seven centers mean seven places of high-risk hail disasters distributing in the two strips, including high value area of Nenjiang Plain, high value area of North China Plain, high value area of Dabie Mountains, high value area of Nanling Mountains, high value area of Southwest China, high value area of Gansu-Qinghai provinces and high value area of Kashi-Aksu Finally, the causes of hail disasters were analyzed Obviously, the scope of hails and hail disasters is different and the hail disaster-affected bodies somewhat can explain why the high-risk areas of hail disasters have the east-directed and south-directed trend The main patterns of hail disaster-affected bodies consist of six types in twenty sub-types, among which crops are the dominant hail disaster-affected bodies From the aspect of dynamic change, four sub-types of maize, cotton, flowers and equipment of communications should be given more attention

Sustainable Agriculture and Rural Development(SARD) in different regions and different developing stages shows different characteristics, and the developing models are varied Through investigations of the SARD practice in Southern Jiangsu where town and township industries are well developed but the conflicts between man and land are sharp, three regional sub models of SARD are identified as :(1)the sub model for intensive, high beneficial and integrated development;(2) The sub model for dual trades of effectively utilizing and protecting resources; and (3)the sub model for multi dimensional development through optimization grouping or regrouping Then based on abstraction of the three sub models mentioned above, the general model of SARD in Southern Jiangsu is generalized, ie , the model of high beneficial, intensive and sustainable agricultural and rural development .

This article focuses on the analysis of the relationship between Ommastrephes bartramifishing ground and marine environmental factors. Based on daily catch data of Ommastrephes bartrami during 1995 to 2000 by China fishing boats and SST isoline chart covering 1995 to 2000 issued every 3 days by Japan Fisher Information Service Center. ArcGIS was used to store, manage and analyze the data. All the catch data were processed and spatialized to display their spatial distribution. The fishing grounds were identified interactively from the catch data maps. Matching Ommastrephes bartrami fishing ground with SST isoline map revealed that the relationship between them could be divided into 3 main patterns and 16 subclasses. The fishing ground in patternⅠis distributed on the tongue of Kuroshio and Oyashio branches, hence called as tongue type. PatternⅠcan be further classified into 5 subclasses,i.e., warm tongue type, cold tongue type, warm tongue + cold tongue type, warm tongue + cold tongue+ warm tongue type, and warm tongue + cold tongue+ warm tongue + cold tongue type. PatternⅡis located on the branch of Kuroshio or Oyashio, so called as branch type. In patternⅡ, five subclasses can be defined,i.e., warm branch type, warm branch + cold tongue type, warm branch + cold tongue+ warm branch type, cold tongue+ warm branch + cold tongue type, and warm tongue+ cold branch. Pattern Ⅲ is distributed on eddy caused by Kuroshio branch encountering Oyashio branch, also named as eddy type. Pattern Ⅲ can be ulteriorly classified as warm eddy type, warm eddy + cold tongue + warm eddy type, warm eddy + cold tongue (branch) + warm tongue type, warm eddy + cold tongue type,warm eddy + cold tongue + warm branch + cold tongue + warm branch type,and warm eddy + cold tongue + warm branch type. Statistical analyses of 239 samples indicate that pattern III has the highest occurrence frequency and highest catch, and pattern II has the lowest occurrence and lowest production. Subclass 35 has the highest occurrence frequency, and subclass 14 has the highest catch. The average CPUE of pattern Ⅲ is the highest, patternⅠthe lowest.Subclass 31 has the highest CPUE value. In 1995 and 1996, patternsⅡ and Ⅲ dominate. In 1997, pattern Ⅲ dominates. From 1998 to 2000, patternⅠis in domination. In August, patternⅡis in domination. In September, patternⅠdominates. In October, patternsⅠand Ⅲ are in domination. In November, patternⅢ dominates. The SST in patternⅠ usually falls between 15℃and 21℃,patternⅡ,17～24℃, and patternⅢ,10～18℃. The temperature grade in the patternⅠchanges slowly, while pattern Ⅲ, has a big grade change. PatternⅠis mainly located on Kurushio branches 3 and 4, patternⅡon Kurushio branches 2 and 3,and pattern Ⅲ mainly located on Kurushio branches 1 and 2.

Kaifeng City, one of China ’s "seven ancient capital cities"and an important member of "Zhongyuan city croup", plays an important role as the regional central city of East Henan province in Henan's urban system City open space is a huge container regulating and controlling urban ecosystem In order to bring Kaifeng City into the situation of sustainable development, it is necessary to improve the construction of Kaifeng ecological city by means of optimizing open space system On the basis of the discussions of the significance and requirement of the construction of ecological city and the necessity of the optimization of city open space system, this paper analyses Kaifeng City ’s salient features and new developing ways, and raises theoretical basis and principles for the optimization of Kaifeng City ’s open space system The overall optimization of Kaifeng City ’s open space system should proceed from two sides The first side is the readjustment of the spatial distribution structure of the city The new spatial distribution structure in Kaifeng City should expand effective area of open space system, strengthen supporting of open space system to ecological capacity of Kaifeng City,and build a base for the integration of the three circles in open space system The second side is the integration of the three circles in Kaifeng City ’s open space system The integration in each circle, and between the three circles, should make Kaifeng City ’s open space turning into an integrated and organic system, from which the construction of Kaifeng ecological city should obtain powerful spatial support The element optimization of Kaifeng City ’s open space system has two contents The first one is the optimization of green open space in the city The municipal government should adhere to the urban ecological norm, create high quality ecological, living and landscape environments, make wooded area, garden area and water area into a natural integration, make point, line and flat green land into an unitary system, thereby, establishing a green basis for the construction of Kaifeng ecological city The second one is the optimization of gray open space in the city The municipal government should adhere to the urban ecological norm, create high quality ecological, operational and building environments, make urbantraffic, outside traffic, square and parking area into a situation of coordinated development,makeroads from east to west, from south to north and loop roads into an unitary system, thereby, establishing a gray basis for the construction of Kaifeng ecological city

The spatial interpolation of some physical geographical elements is becoming increasingly important nowadays in resources management, disaster control, environment improvement and the research of global change. The core of the spatial interpolation of those elements is to seek the functions that can reveal their characteristics of spatial distribution. But, as for specified regions and sample data, there are many functions in the list for choice. And the best choice is difficult to make because of the complex effects from theoretical foundation, algorithm, temporal spatial scale, and attributes of sample data. By referring to the major achievements in the interpolation research field, this paper comes to the point that the accuracy of certain spatial interpolation depends on its capability of reflecting the element's spatial variance and spatial correlation. Models using other elements as variables, when regression variable has high correlation with interpolation variable, will give more accurate results than others, because they have better reflection of spatial variance. Models without other element variables change in accuracy according to their consideration of the anisotropic characteristics or not. With spatial temporal scales' variance, the disposed spatial variance and correlations will be different, which affects the interpolation accuracy. The density, spatial distribution, data extent of sample points also makes the interpolation results different for the same reason. As for applications, the optimal interpolation method should be picked out after the analysis of those spatial characteristics embedded in the sample dataset.

Since the 1950s, Western economic geography has undergone major paradigmatic transformations, influenced in part by institutional and technical changes in global economic production. Mainstream economic geography has witnessed major epistemological shifts away from earlier "mere description" to logical positivism, and from meta-theorization aiming at scientific prediction to place- and region-centered analysis for hermeneutic understanding. A new economic geography has appeared characterized by institutionalism, "cultural turn" and pluralism. Geographers on both sides of the Taiwan Strait have not had significant interactions with mainstream economic geography. Not only should we be familiar with the theories of mainstream economic geography, we should also critique them and modify them using the findings of our fieldwork conducted on the Chinese mainland and in Taiwan. We should establish our own intellectual identity and internationalize our scholarship.

A micro-level input-output analysis on farmland is important in understanding the man-land relationship in rural areas, particularly in the mountainous regions. This paper is based on a survey undertaken in a small rural mountainous village in Wugou of Gongyi city, Henan Province in April 2003. The survey covers 482 plots of farmland from 81 households. Data collected include 50 attributes for each plot. The amount of input and output is simplified by converting into energy equivalent. By employing a revised Cobb-Douglas production function (Y=AX α), the input and output analysis based on the survey data finds the following results. (1) The energy input-output ratios, as well as energy transfer efficiency in the farmlands declines along with the increase in elevation of the lands. An exception is those fields close to the residential area of the village site. (2) A significant negative correlation between slope gradient and energy input-output ratios exists. But analysis based on three classifications of slope gradient further reveals that the farmlands with medium- and lower-slope gradient have the highest ratios in energy production. (3) Other factors of landform description, such as slope aspects, slope position and slope curvature also affect energy transfer in various ways. These facts imply that farmers in the rural mountainous areas heavily rely on their past experience in utilizing natural resources. There is a big room for improving the man-land relationship.

Man-land relationship has become one of the most sensitive problems in agricultural development, and study on land productivity and population supporting capacity opens up an effective way for quantifying regional man-land relationship. In this paper, we discuss present and future environmental capacity status and variation trend in Xiangjiaba reservoir area on village basis with land potential productivity degression method and bearing capacity evaluating model, regarding cultivated land as study object. According to geographic status, land bearing capacity evaluating region is confirmed, covering 23 832.91 ha and involving 21 towns or 174 villages. Coupling analysis of land use and physiognomic characters in the study is conducted with GIS and RS, and then the integrated spatial-attribute database is established. Supported by perennial sun light and temperature data, soil physio-chemical attributes on village scale, cultivated land spatial distribution and main crops (including paddy, wheat and corn) growing period in the reservoir area, the appraising index system of land productivity is set up, synthetical crop productivity of cultivated land on village scale is evaluated with land potential productivity degression model. Taking into consideration comparatively well-off standard of living for local people,including per capita grain and farmland availability,as capacity index of grain to support population, we establish land bearing capacity model based on reservoir construction planning and spatial pattern of land productivity to forecast per village farmland resource potential carrying capacity at present and in the near future(2012), and put forward environmental capacity of the whole study area coincided with local agricultural development. The result shows that multiple-cropping practice compared with other farming methods can gain even greater population supporting capacity; it is more reasonable to study land population supporting capacity based on output of grain rather than on farmland area, however, they should be combined with each other in practice; because the impact of fully implementation of land conversion from farmland to forest and grassland on land carrying capacity is greater than changes of unit area output of grain, hence under the same farming practices, the future land population supporting capacity does not increase but is smaller than the present environmental capacity, presenting an overall decreasing trend inevitably; environmental capacity of reservoir area is inclining to saturation, man-land conflict stands out;and population supporting capacity of cultivated land should be increased to some degree by means of increasing output of grain through expanding sown area of paddy and ameliorating breed.

Based on progress reviews the of eco city study at home and abroad,the rules of optimization and reorganization of spatial structure of eco city and "the green center with around groups network spatial structure model" was put forward taking Xiangfan as a case First, the present eco city's research status and successful practices abroad, and the concept of eco city, the urban eco areas dividing, planning and design, the evaluation index system and other theories and methods of eco city in China since the 1980s were reviewed Second, the authors put forward the rules based on those reviews, which guide the optimization of spatial structure of eco city They are: ① to perform natural harmoniousness fundamental to human; ② to develop at an appropriate scale and suit measures to local conditions; ③ to practise landscaping and achieve perfection and high efficiency;and ④ to pursue overall coordination and benign circulation And with these rules, the authors commend a new model of spatial structure named "the green center with around groups network spatial structure model". Third, based on the analysis of the evolution and problems of its spatial structure, four development forms of urban land use were compared and urban land use for construction were comprehensively evaluated Combining population prediction, the authors suggest that the regional function collaboration of the peripheral area with Xiangcheng and Fancheng should be strengthened, and the planning idea of "a continent, three mountains, three rivers"should be stressed to guide the city change to the green centre with around groups network spatial structure in the process of optimization and reorganization of spatial structure for creating a modern ruralizing eco city Finally, a authors think that the eco city is an inevitable trend of city development; the establishment of the city development leading mechanism makes the city turning gradually to an eco city that is more suited to human settlement;and green centre with around groups network spatial structure model is one of the ideal urban spatial structures

Research on drainage basin erosion and sediment yield amount is not only an important task in physiognomy, but also an important one in river harnessing and water conservancy construction. Drainage basin runoff and sediment formation is a very complex physical process. The fundamental reason for it is the result of rainfall and drainage basin underlying horizon reciprocity. Mathematically, it is an altitudinal nonlinear mapping relation from drainage basin underlying horizon and rainfall conditions to drainage basin runoff and sediment transport. The structure of drainage basin sediment yield statistical models is simple, convenient to calculation and serves as a power tool available for sediment yield prediction. Many researchers according to their study region and measures, established different empirical statistical models. Although so many empirical statistical models were set up, the factors they considered were not the same. This paper tries to conducted an integrated analysis of the effect of rainfall, runoff and physiognomic forms on drainage basin sediment yield, on the basis of considering sediment yield mechanism and to establish sediment yield formula for single rainstorm in Chabagou drainage basin which will have a certain sediment yield mechanism. It is also hopefully to offer some references for other researchers in establishing drainage basin statistical models. Through integrated analysis of the effect of rainfall, runoff and physiognomic factors on sediment yield, we can find that as for the effect of rainfall amount and its temporal and spatial changes on drainage basin sediment, the correlation coefficient of rainfall amount and rainfall intensity product PI with drainage basin sediment yield modulus M s is the highest. But when we consider rainfall runoff effect on drainage basin sediment yield, rainfall action has become negligible, the main factors affecting sediment yield are runoff depth H and flood peak discharge Q W. The effect of runoff depth H on sediment yield is essential, but its effect on sediment yield of different scales of drainage basins is the same. Flood peak discharge Q W is mainly accountable for the remarkable difference in sediment yield of drainage basins of different scales. With the increase of area, the effect of flood peak discharge Q W on drainage basin sediment yield also weakens. Of the physiognomic factors, drainage basin area and ravine density play the leading role, and drainage basin channel gradient ratio is on the comparatively secondary position.

This paper analyzes how the globalization of producer services has reshaped China's regional markets and spatial structure from the perspective of advertising. Advertising is a highly internationalized and conglomerated sector. As a latecomer, the emergence of China's advertising after reform has occurred on a global stage. The major findings of this paper are: 1) As a result of the dominance of multinational agencies, China's advertising companies have been evolving into professional agencies. International standards and management practices have also been gradually adopted in China. That is to say, offices of multinational agencies in Beijing, Shanghai and Guangzhou have integrated China's advertising into a globalized institutional space over the past decade. 2) This spatial agglomeration of advertising in China's three major metropolitan regions has demonstrated the process of shifting from "serving markets and customers" to "the formation of a service market." 3) In terms of the production of advertising, China remains downstream in the global division of labor. However, with its large market and rising national brands, China may have increasing negotiation power, and, thus, push China's advertising industry into a position of greater prominence with respect to product placement and communicative strategies. 4) Due to the large scale of this national market, the advertising industry must develop localized media plans and promotional products when entering into specific regional markets within China. This has resulted in increasingly local versions of standardized global advertising products. In conclusion, this paper contributes to theoretical discussions of global city/world city networks. Through the development of producer services, we can see the specific routes through which globalization penetrates into localities. The entry of multinational businesses has compelled emerging markets to accept and adopt globalized institutions, procedures, and ideologies, and, furthermore, led to the integration of secondary regions and markets into this space. In short, global cities are mediating the globalization of metropolitan regions both institutionally and spatially.

Urban land-use planning is a complex, time-consuming process and involves complex decision-making problems. Generally, urban land-use planning is a multi-objective and nonlinear programming problem with high dimensionality, but it is difficult to run into numerical and high time cost problems with conventional optimisation tools. Currently, planners have to use some qualitative methods to generate urban land-use plans, this process has long been viewed as a ‘black box’ inside which planners are more or less subjective and the resulting land-use spatial scheme may be non-optimal. This paper develops a method called simulated annealing algorithms for handling such a conflict. The simulated annealing algorithm is quite effective and efficient for dealing with many complicated mathematical models. The mathematical optimisation model for generating optimal urban land-use plans was established, in which two main objectives, the minimum development cost of land and maximum spatial harmony were considered. Since spatial constraint considerably slows down the process of searching feasible solutions, some spatial constraints are straightforwardly integrated into the objective function in our SA, including the contiguity and compact form constraints, while the direction and distance constraints are combined into the objective function by means of adding accessional penalty cost to the objective function. The SA method is successfully applied to generate optimal land-use plans for Muyun industrial district in Changsha city, but a final realistic plan requires more detailed modeling. SA presented in this paper should therefore be regarded as a fast and simple technique useful in an early stage of the decision-making process. However, in order to maintain the transparency of urban land-use planning, robust and simple techniques as simulated annealing are promising.

In the spring of 2001, several duststorm events occurred in northern China which seriously threatened production and people’s life and caused troubles to air transportations in South Korea and Japan. The duststorm weather was a strong wind erosion process in terms of duststorm source, transportation and precipitation. The mechanism of duststorm process is the cornerstone for duststorm forecast model. Estphal(1988), Joussaume(1990)and Gillette (1989) published a wind erosion based model;Shao (1997)and Lu (2001) took five different factors into account developing an integrated model including climate condition, land cover/change, wind erosion, transportation as well as precipitation factors. The duststorm also had very close relation with surface physical parameters such as soil moisture, temperature roughness and radiation which were the very important parameters for land and air energy exchange. They also played important roles in duststorm process. Brest(1987),Tian(1990) and Zu Hanwen(1993) pubilshed their retrieving models for albedo and temperature using AVHRR data. By using remote sensing data to monitor dust clouds change, transportation road and to retrieve surface temperature, soil moisture, roughness in compensation to the shortcomings of sparsely located observation stations and discontinues data collection. The data retrieved from satellite has become very important data source for duststorm monitoring. Chinese and Japanese-initiated a joint project in 2000 to set up ground observation stations along dust source areas such as transportation roads,precipitation areas for collecting TSP (dry dust precipitation) and utilizing AVHRR data to retrieve albedo(surface energy).And then data were selected from retrieved albedo temporal imageries to make curves and comparison was made between albedo curves and TSP curves. The result showed that there were good correlation betweens the two kinds of curves. It was proved that the LST/Albedo could be one of the physical parameters for predicting duststorm in future monitoring systems.

The dynamic simulation and scenario analyses on the spatio-temporal patterns of land use change, as a hotspot in the research field of land use and land cover change(LUCC), is involved with many driving factors. This paper reclassified the driving factors into three categories (stable controlling factors, seasonal changing factors and socio-economic factors) and revealed the influencing direction and intensity of different factors on land use change by logistic analyses between land use change and its driving factors. Furthermore, regarding CLUE-S model as the modeling framework, this paper designed a dynamic simulation model on the spatio-temporal patterns of land use change in Taibus County. In terms of the running results of the System Dynamic Model of Land Use Change and the change of social and economic factors, this paper realized the dynamic simulation of land use change as well as the scenario analyses of baseline, ecologically-oriented and economically-oriented models in Taibus County. The comparisons of the simulated results of baseline, ecologically-oriented and economically-oriented scenarios disclose the competitions and successions in spatial and temporal scales affected by the integrated effects from all kinds of driving factors. the findings show that the northeastern and northwestern sections covered by unused land at present will become the most sensitive belts for land use change, which further reveal the necessity of macro planning for land use in those areas. In this sense, the research results will serve the decision making on land use planning, the rational exploitation of land resources and the implementation of sustainable development strategy of Taibus County.

Based on detailed survey data of land use from early 1991 to late 2001, using models such as synthetic dynamic degree model,conversion rate model, new increase rate model, synthetic index model and synthetic index change model of land use, this paper analyzed great changes in land use in Shaanxi Province during this period of time.Figures indicated that 119.40×10 4hm 2 of farmland, 2.21×10 4hm 2of garden land,7.64×10 4hm 2 of forest land,21.02×10 4hm 2 of grassland,1.52×10 4hm 2 of rural residential land and city and town land,0.13×10 4hm 2 of traffic land,1.07×10 4hm 2 of waters and 14.85×10 4hm 2 of unused land changed to other types of land. Meanwhile, 10.44×10 4hm 2 of farmland, 45.47×10 4hm 2 of garden land, 59.79×10 4hm 2 of forest land, 29.28×10 4hm 2 of grassland, 9.65×10 4hm 2 of rural residential land and city and town land, 2.66×10 4hm 2 of traffic land, 2.36×10 4hm 2 of waters,and 8.19×10 4hm 2 of unused land were converted from other types of land. The synthetic dynamic degree of land use in Shaanxi is 0.726%·a -1. The covertsion rate of farmland is 1.885%·a -1, the biggest number among conversion rates of other land use types.Synthetic index of land use degree in Shaanxi is 2.301 in 1991, and 2.282 in 2001. The conclusions are drawn as follows: (1)Land use changed greatly in Shaanxi Province from 1991 through to 2001. Garden land changed most greatly, with cultivated land, traffic land, residential and urban land, and grassland also witnessing greater changes. (2)Land use in Yangling was most active and in Hanzhong was least active. The overall relative change rate of land use in Yan'an was high, because Yan'an emphasized the adjustment of industrial structure, put the policy of returning cultivated land to forest and grass into effect, and improved the infrastructure construction such as traffic conditions during the last 11 years. (3)Urban, rural residential and traffic land uses increased quickly, which indicates that under the situation of the West China development, the traffic conditions were improved and the urbanization steps quickened constantly in Shaanxi. (4)The land use degree in Yangling was the biggest. The one in Shangluo was the least. The land use degree in Weinan, Xi'an and Yangling increased during the last 11 years, and the land use degree in other regions decreased. (5) The cultivated land returning to forest and grass mainly happened in south and north of Shaanxi and agricultural structure adjustment mainly in the middle of Shaanxi.(6) The driving factors of land use change in Shaanxi are natural factor, policy factor, economic adjustment and population factors.

This paper discusses the property and marks of urbanization as a self organizing process, which can be thought of as a kind of phase transition from a rural to an urban settlement system. Several empirical observations including fractal structure and rank size distribution can be used to identify the self organized criticality (SOC) of urbanization dynamics. Fractal structure such as central place landscapes in spatial field and the rank size distribution associated with Zipf ’s law in hierarchical field always ‘emerge ’ while urban systems in a region approach to the self organized critical state of urbanism. The central place hierarchy can be characterized with a set of scaling laws as follows: N m=N 1r m-1 n,P m=P 1r 1-m m,A m=A 1r 1-m a . From these exponential scaling laws, we can derive the power laws such as the three parameter Zipf law, P(r)=C(r-ζ) -d , and the law of allometric growth, A m=ηP b m .The exponential distribution indicates random process, while the power law implies some order in complex systems, but we find the unity of opposites between order and chaos of urban systems through the derivation of power laws from the exponential type scaling laws. Moreover, this means that the spatial network of central places and the hierarchical structure of city size distribution reach the same goal by different routes. This in fact corroborates the viewpoint that both the urban hierarchy and spatial network represent the different sides of the same coin. The self organized networks of cities usually become scale free because of the dynamics of urbanization. The map of the urban network patterns in hierarchical field is just the rank size distribution, which appears in the larger picture, not at the level of an individual city. Once the distribution forms, it will become very stable over a long period of time. The formation of the scale free network of cities associated with the rank size distribution is an information rich evolution, which can be simulated using cellular automata (CA) models, cellular space (CS) model, multi agent system (MAS), and so on. Simulation as an experimental tool may be very useful for us to research spatial complication proceeding from urbanization dynamics. However, the simulation based on computer graphics doesn't help us conceptually in understanding the rules of behavior of urban systems at the higher level. As a complement, post modern mathematical theory esp. fractal geometry, chaos mathematics, renormalization group, etc., will play a significant role in the studies of self organizing urbanization.

Desertification issue of farming pastoral interlaced area has been paid attention to by the whole society In different areas, the developing mode and process of desertification are quite different It is characterized by distinct regionality and differences in the cause of desertification. A noticeable scientific subject is the role of seasonal rivers in the evolution of desertified landforms in semi arid region Siziwang county located in the central part of Inner Mongolia and to the northwest of Ulanqab League lies between 110°20′～113°00′E and 41°10′～43°22′N It covers an area of 24016 km 2 , and topographically,it is higher in the southern part than in the northern Tabu river has many seasonal branches It is the longest river in Siziwang county In Tabu river basin, there are abundant outcrops of Tertiary and Quaternary fluvial lacustrine facies, and there are many sandbelts and ridges along the branch rivers At present, the most serious desertification process is in Ulanqab League of Inner Mongolia Taking Tabu river basin of Siziwang county as an example, and based on RS image processing and analyzing, the paper researches the role of seasonal rivers in the evolution of desertification in semi arid area, and analyzes idiographic mechanism and pattern of desertification development under combined action of wind water integration In arid and semi arid areas, especially when anthropogenic activities are involved, surface vegetation is sparse, and even barren ground is seen. Under the effect of rainstorms in summer, a great deal of mud and debris materials are transported by torrents, and these materials accumulated in the broad valleys of the middle and lower reaches of the rivers With the silting up of mud and sand, and the broadening of the river courses, driftsand is spreading to both banks In spring, with the co operation function of "the narrow tube effect of wind" and the partial circulation of air current, the sand spreads further around, and connects with the alluvial fans, resulting in the formation and development of large scale desertification. It eventually may lead to desertification in the whole area

This article focuses on analysis of status and characteristics of nutrient salts carried in typical rivers in the urban areas, the combination of urban and rural areas and the severely polluted agricultural areas by monitoring water quality and flow at outfall of rivers into lake after three rainfall events during early wet season in three different catchments of Dianchi Lake. The research result indicates that total quantities of nitrogen and phosphorus nutrients in the rivers into the lake in different catchments are generally controlled by rainfall process and characteristics of catchments, runoff flow and concentration of nutrient salts in runoff water. After three rainfall events, the maximum values of TP, KN, NH 3-N, NO 3-N and NO 2-N into lake appear in the river (Daqing river) at combination of urban and rural areas, with accumulated quantities of 11,374.3, 127,971.7, 85,365.4, 923.4 and 841.2 kg respectively, while the maximum unit area loadings of TP, KN, NH 3-N and NO 2-N into lake appear in the river (Wulong river) at urban area, with values of 535.7, 5,860.5, 3,821.9 and 24.6 kg/km 2. It is very complicated that the rainfall process influences the nitric and phosphoric nutrient salts which flow into Dianchi Lake by rivers in different typical catchments areas. Among the influencing factors, rainfall of the initial stage, rainfall frequency and rainfall intensity are very important. The runoff amount of nitric and phosphoric nutrient salts is controlled by changing curves of flux functional equation Q(t) and concentration functional equation C(t) finally during the rainfall process, with different conditions of dry time length, land use status, district draining status and properties of suspended particulate matter. So the total quantities of nitrogen and phosphorus nutrients in the rivers into the lake are different. Research reveals that the conception of total loading capacity in unit area in the rivers into the lake can simplify the calibration of important parameters of hydrological models and kinetics models which have all kinds of remove and transformation processes. The total amounts of nitrogen (counted as Kjedahl's N) in rivers into Dianchi Lake in unit area have such a sequence of Wulong river (5860.5kg/km 2)>Daqing river (1421.9kg/km 2)>Baoxiang river (129.0kg/km 2). The total quantities of phosphorus(counted as TP) in rivers into Dianchi Lake in unit area have such a sequence of Wulong river (535.7kg/km 2)>Daqing river (126.4kg/km 2)>Baoxiang river (22.2kg/km 2). The most highest total amounts of Kjedahl's N and TP in rivers into the lake appeared in the river at urban area and the most lowest total amounts appeared in the river at rural area. Although the amounts and concentration of NO 3-N and NO 2-N have been raised obviously, the amounts of NO 3-N and NO 2-N which flowed into Dianchi Lake in unit area are still the lowest. The amounts of NO 2-N observe a sequence of Wulong river (24.6kg/km 2)>Daqing river (9.35kg/km 2)>Baoxiang river (4.12kg/km 2). The amounts sequence of NO 3-N is arranged with Daqing river (10.3kg/km 2)>Wulong river (5.71kg/km 2)>Baoxiang river (5.10kg/km 2). All these evidences testify that the discharges of NO 3-N and NO 2-N are still influenced comparatively by city residential areas.

In China ,s land use practice, land readjustment has contributed a lot to the realization of the rational disposition of land resource and to the improvement of the land use efficiency and the ecological environment. Meanwhile, land readjustment has caught increasingly concern in land use science research. Regarding land readjustment, one of the essential contents should be the potentiality of land readjustment, upon which land arrangement plan can be plotted. However, so far as the theoretical and empirical researches in China ,s mainland are concerned, few discussions on the connotation and evaluation methodology of land readjustment potentiality have been carried out and arable land readjustment as land readjustment potentiality has also been rarely dealt with in mainland China. Based on the review of arable land readjustment potentiality abroad, it is argued that the connotation of China ,s arable land arrangement potentiality can be defined in three respects as optimizing land structure,optimizing arable land structure and improving arable land productivity.To this end,we build arable land readjustment potential evaluation index system.Yanqing county located in northwest of Beijing is an important ecological zone.The land readjustment project jointly conducted by the Center of Land Consolidation and Rehabilitation of Ministry of Land and Resources with Holland is also in Yanqing county, where a case study was carried out. The result indicated that the evaluation index system is feasible, conforming to the actual conditions of Yanqing. Evaluation methodologies with special attention to arable land readjustment are introduced, which are expected to shed new light on relevant researches.

Research of runoff generation and routing mechanism is the foundation of hydrological simulations. Further analysis based on hydrological data is an effective means. Lushi basin (4623km 2) located above Luohe in the middle Yellow River is a typical tor-forest area. Its runoff generation and routing characteristics are different from the others’. To further research the asymmetry of precipitation spatial distribution, the following three indexes can be used: dispersion coefficient of basin precipitation (C V), asymmetry coefficient of basin precipitation (η),and ratio of the maximum and the minimum precipitation in basin area (α).To separate runoff components and show changes of air temperature, evaporation, precipitation,runoff and rainfall-runoff coefficient, a hydrograph recession curve displacement method and mass departure method were respectively used. The analysis of the selected 43 rainfall-runoff data from 1971 to 2000 revealed that the region's rainfall spatial distribution is very asymmetric with the existence of a distinctive a storm center; its mean dispersion coefficient of basin precipitation (C V) is 0.51, mean asymmetry coefficient of basin precipitation (η) 0.53 and mean ratio of the maximum and the minimum precipitation in basin area (α) 16.06. Its routing mechanism and modes are very complicated, including over-infiltration and over-fall patterns.The annual direct flow accounts for 74.7% of the total, routing time is 18.0h and lag time 13.7h. An in-depth analysis of routing characteristics on the variational conditions resulted in important conclusions : changes of annual runoff yield and rainfall-runoff coefficient were resulted from rainfall characteristics; changes of underlying surface and human activities did not cause prominent effect on the relation of rainfall-runoff; while to flood, biological protection and water and soil conservation measures increased the cover degree of vegetation and forest, improved interception and soil fixation abiligy, reduced runoff generation capacity and improved the correlation of flood-runoff in the study area, to a certain extent.

The shrinkage of China’s cultivated land is a world-wide concern, which is believed to arise from the increase of land used for construction purpose. In order to obtain a timely understanding of the land expansion for urban construction and the decrease of cultivated l and in China, remote sensing is being employed to monitor the expansion situation of land used for construction in the cities having above 500,000 non-agricultural population during various periods, and the accuracy estimation of the monitoring results constitutes an improtant aspect in this task. Up to now, many estimation indexes have been proposed which serve as a favorable base for future research. However, there still exist some drawbacks to be solved.In the article, a method of stratified random sampling is presented to obtain the accuracy analysis of remote sensing monitoring.The accuracy assessment is comprised of technological and regional assessment. It involves the assessment system of accuracy monitoring, the capacity determination of the stratified random sampling method, the procedure for sampling and evaluation, and the statistic analysis and result expression of the random survey. In addition, to verify the feasibility and suitability of this kind of method,the practice of the above system, based on data for Beijing and Chongqing in 2001 collected by remote sensing and fieldwork, is performed.Our work successfully applied the sampling theory to geoscienlific survey, which is of great theoretical and practical significance.

This paper deals with the physical and chemical properties characteristic and its affected factors of latored soils in southern subtropical hills Results showed that compared with the soil under zonal natural vegetation it suffered more physical and chemical properties degradation under secondary or man made vegetation It was found that the physical properties degradation in latored soils was characterized by the lowering of aggregates stability with decreasing water stable aggregates, the deteriorating of soil porosity with increasing bulk density and decreasing bigger pore content and the deteriorating of water properties with lowering water permeability and available water retention capacity For natural latored soils, the increasing bulk density and lowering bigger pore content were more obvious, but for cultivated one, the lowering structural stability was more serious It was showed that the chemical properties degradation was characterized by nutrients improvement and nutrients supplying ability with lowering organic matter, nitrogen, phosphate, potassium and cation exchange capacity Statistic analysis indicated that the 10～0 25mm water stable aggregate and its mean geometric diameter value were obviously positively correlated with the organic matter content and total nitrogen content in the soils, that the total porosity and >0 05mm porosity were also positively correlated with the organic matter content in the soils; that the soil structure coefficient and <0 005mm porosity were positively correlated with soil clay content This means that nutrients improvement, especially the organic matter deficient might be the main factor which caused the latored soils physical properties degradation Natural vegetation destroyed by human disturbance might induce soil nutrients improvement, in order to prevent soil degradation, more attention should be paid to protecting vegetation and increasing soil organic matter content

Nowadays, great efforts have been made on distributed hydrological modeling It is believed that distributed hydrological model can describe the hydrological processes in more detail and more physically On the other hand, the rapid development of computer and information technology has turned distributed hydrological model from scientific concepts to application reality In this paper, we have applied the macro scale distributed hydrological model SVAT&HYCY to Lushi Basin, which is located at the upstream of Luohe River Firstly, we have established a graphic user interface integrated three major components including SVAT, HYCY and ROUTING With the support of GIS, the basin has been divided into 54 10km×10km grids based on 100×100m DEM Also, the Thissen method has been applied for spatial interpolation of meteorological data, such as precipitation, temperature, relative humidity, sunshine duration, atmospheric pressure, vapor pressure and wind speed For the whole basin, data from three meteorological stations and 33 rain gauges have been used From the model, we have obtained evapotranspiration of the basin Comparing with precipitation patterns, we found that evapotranspiration is not only under the impact of precipitation but also influenced by terrain, land use and land cover, etc Furthermore, comparing the simulated runoff with observed one from 1990 to 1996, we found that in some years (1990, 1992,1994,1995 and 1996), the simulated runoff is quite close to the observed one However, in 1991 and 1993, the difference is quite significant The differences implied that the structure and parameters of the model may not fit with the real hydrological processes exactly On the other hand, the availability of model input, especially precipitation information, may also have great impact on the results Though there is still deficit in the distributed hydrological model, it has a bright future It is believed that with the development of GIS and RS, the distributed hydrological model will be improved widely.

Landscape ecology could provide not only new theory and methods for scenic spot planning, but also scientific bases for improving the planning through study on the possible landscape ecological effects caused by implementing the planning. Taking Muyan Scenic Spot of Nanjing as an example, the possible changes before and after implementing the planning in such aspects as landscape pattern, landscape ecological quality, landscape stability are analysed. Based on this study, improvement of the scenic spot planning has been proposed. This paper contains the following contents: 1)According to the requirement of landscape evaluation and planning, landscape unit survey and mapping are carried out in Muyan Scenic Spot, and a landscape classification system in this area is established; 2)based on the scenic area planning, possible landscape changes are analyzed on the assumption that the planning has been implemented; 3)changes in landscape spatial structure after implementing the planning are analyzed by using landscape spatial pattern analysis method; 4)landscape ecological quality before and after implementing the planning is qualitatively and quantitatively estimated; 5)based on the analyses of recovery, persistence, and noise immunity of the landscape, landscape stability before and after implementing the planning is evaluated; and 6)according to the above evaluation and analysis, landscape ecological effects of the scenic spot are concluded and suggestions on planning improvement are made.

Water is one of the most essential natural resources, especially for urban areas. Water shortage is a common problem confronted by many cities. A number of countermeasures, including saving, pollution control, seeking new water source, have been put forward to solve the problem. The purpose of this paper is to identify a better one from the measures and to facilitate sustainable use of urban water resources. Therefore, it is necessary to assess the effect of implementing the countermeasures. In order to achieve both conservation and effective utilization of water resources, a careful analysis of the region is very important. In the study, the relations among population, economics, government and ecosystem almost always constitute highly complex dynamic systems. That makes some common methods useless for solving the problem of the complex systems. So a holistic point of view is to be adopted and considerable amount of effort must be devoted to the analysis of water resources system (WRS) and strategy improvements. System Dynamics(SD), founded by J. W. Forrester in the 1950s, has been testified to be an effective way to the analysis of strategies and decision-making. In this study, SD is applied to quantitatively analyze and to synthetically assess the measures of urban water resources, in virtue of multi-factor general evaluation. Based on the research of water circulation and the law of water quantity transformation, within the fields of urban areas, this paper endeavors to find out the main dominant factor influencing sustainable WRS development, to build WRS system dynamic (WRSSD) model for dynamical simulation, and then to apply the multi-factor general evaluation to the simulation results. In this paper, WRSSD model is used in the WRS of Shenyang City as a case study. Four policies are taken into account: no-does, frugal use, pollution control, and sewage purification and reuse. Based on the quantitive analysis of the long-run impact of the measures, the effects and influences of different policies are fully clarified. The final result indicates that: (1) frugally use and pollution control are not enough, regarding the constant growth of water demand; and (2) the gray water will be an important part of water resources. The study can provide a scientific foundation for the rational development and utilization of urban water resources. The case study confirms the practicability and operability of the method. It indicates that SD model, in virtue of multi-factor general evaluation, is a useful tool for sustainable development of urban water resources.

In North China, an unprecedented heavy sand-stormy weather with high frequency took place in the spring of 2000. Dramatically, it brought direct damage to the region around Beijing, which has aroused even more extensive concern of personages of various circles. Sand-stormy weather research has been widely carried out since then. Therefore, in this paper, based on the climate data from 1951 to 1996 and eco-environmental data, employing climate statistics methods and geographic information sciences(GIS), the author took the land around Beijing as a case to study its characters of the temporal and spatial pattern in the past fifty years. The annual sand-dust storms day was selected as the major index to divide the region into four districts, then the environmental background was analyzed based on data extracted from the remote sensing images of the 1990s. This research demonstrated the spatial distribution and temporal change of sand-dust storms in this area, leading to the following conclusions: diurnally, afternoon(from 12 p.m.to 18 p.m.)was the period of sand-dust storms;seasonally spring and late summer were the sand-dust storms most easily happening periods;interannually,the 1950s to the 1960s witnessed the high value period of the sand-dust storms while the number of the sand-dust storm days tended to reduce in the 1970s and the 1980s but increased in the 1990s again. We also found that the most easily happening period corresponded to the dry and cold climate. As for the spatial distribution, the high value regions were located in the marginal areas of Otindag Sandy Land and Hobq Sandy Land, especially in Siziwangqi-Zhurihe, Erenhot-Damaoqi, Daladqi-Junggarqi-Uradqi.

Flow routing model (FRM) plays important roles in the distributed hydrological modeling. Whether a simple or complex FRM is chosen depends on the relative relationship between the time resolution and the lagging time of routing. Generally, the FRM of a distributed hydrological model(DHM) consists of three components: the first is subdivision method of the basin; the second is the routing path; and the last is the routing method based on the routing path. In order to decrease the runtime of model, an efficient routing method, the so-called Ranked-Grid-based Kinematic Wave Routing model (RGKWR), is developed in this paper. This model applies the kinematic wave method to successive routing on ranked raster grids. Raster grids can be divided into different ranks due to each grid's flow direction computed by the single direction algorithm. We define the basin's outlet grids as the first rank, and the grids from which water flows into the first ranked grids as the second rank, the rest can be deduced by analogy, so the most upstream grids are defined as the highest rank. Flow routing is undertaken from those grids having higher rank onto the grids having lower rank.This paper puts forward the classifying method for raster grids, discusses the kinematic wave model and its numerical solutions, and carries out a case study on Chaobaihe River Basin in North China. The basin, with a drainage area of 13,846 km 2, has two outlets to Miyun Reservoir: one is Xiahui hydrologic station on Chaohe River, the other is Zhangjiafen station on Baihe River. The whole basin is divided into 55,444 grid elements at a 500-m resolution, with the Chaohe River basin partitioned into 298 ranks, and Baihe River basin 398 ranks. The application shows RGKWR based on GIS/DEM is reasonable and efficient.

Limestone dolines are much developed in Lunan Stone Forest National Park with soil mantle We choose 9 sites in the bottom or slope of 4 dolines in Lunan Stone Forest in order to study the soil particle size distribution, water content(%), chemical composition of soil developed in the doline bottom or on the slope and their relationship with doline development Study shows that soil water content, chemical composition and particle size distribution are all controlled by karst topography The soil in the bottom of the depression has a lower water content, total Al 2 O 3 and Fe 2 O 3 content than that of the soil in the slope of the depression, However, total SiO 2 of soil in the doline bottom is higher than that of the slope We mainly study the clay and silt content of the soil mantle soil in doline bottom has higher silt content and less clay content than that of the soil on the slope Research results show that with the increase of soil fine grain size, the SiO 2 content decreases while both of Al 2 O 3 and Fe 2 O 3 content increase The water content of soil is highly positive related with content of fine grain size and strongly negative related with content of coarse silt content In order to determine the limestone erosion rate at different depths, 27 limestone tablets were buried at different depths(20 to 60 or 120 cm, one layer every 20 cm) of soil, which were developed in the bottom and slope of a doline in November 1999 Two years later(November, 2001), 25 tablets were exhumed and sent to lab to measure their weight loss then calculate dissolution rate Result of dissolution experiment shows that limestone dissolution rate in the soil of doline bottom is much higher than that in soil on the slope At the same time, result of correlation analysis shows that limestone dissolution rate is highly positive related with content of coarse silt content(R 2 =0 85) and strongly negative related with content of fine grain size(R 2 =0 84) To some extent, even though limestone dissolution rate was decided by soil CO 2 concentration and soil chemical composition, it is still affected by the soil particle size distribution

Wetlands serve as source, sink or transfer of nitrogen(N), and spatial distribution of N in wetlands also significantly influences most ecological processes of wetlands. Some researchers have testified that soil nutrients in wetlands had higher spatial heterogeneity. Geostatistics have been successfully used in soil science and become an efficient tool to research spatial heterogeneity of soils since the 1970s. Xianghai wetland is a one of international importance, which is located at the downstream of Huolin river catchment of semi-arid area and is a typical agriculture/pastoral ecotone and ecological fragibility zone in the west of Jilin province. Xianghai wetland has been the important factor keeping ecological balance and one of the natural barriers for eastern ecological environment in this region. At present, Xianghai wetlands are potentially threatened as a result of such human activities as overgrazing, building large-scale irrigation works and unreasonable reclamation. Spatial distribution pattern of total N and N forms in marsh soils during plant budding were studied using geostatistics of Xianghai wetlands in May, 2001. The results showed that, with the exception of ammonium N, other forms of N and total N were mainly distributed on surface soils, appearing a decreasing tendency gradually with the increase of soil depth; the total N and all forms of N contents had higher statistical variations; on surface soils, the statistical variation of the available N was the highest, but ammonium N the lowest, with variation coefficients of 65.64%and 49.51%, respectively. For other soil layers, soil organic N, total N and nitrate N had higher statistical variations, but available N and ammonium N had lower statistical variations. The spatial distribution pattern of total N was similar to that of organic N; it was highly consistent in distribution areas with higher or lower contents of N forms; with the except of the fact that available N concentrated on top soils, other forms of N appeared accumulation peaks in deeper layers of soil profiles. Both N behavioral processes and environmental factors controlled spatial distribution pattern of N, but quantifying their influences on spatial distribution pattern needed further studies.

NDVI is an important index denoting a region's vegetation cover. In this paper, the Yellow River Basin is divided into 16 sub-regions and their NDVI series of 1982-1998 are obtained from AVHRR-NDVI of Pathfinder. The spatio-temporal changes of NDVI in the Yellow River Basin are analyzed. The results show that:(1) In general, NDVI in all sub-regions reaches peak value in July or August within a year in the Yellow River Basin. In average in the 17 years, the NDVI values show the increasing trends in August and in annual average in other sub-regions except that they show the downward trends in the Sanhua and the above Longyang gorge sub-regions in August. These imply that the coverage percentage of the vegetation presents a rising trend and the ecological quality is being improved on the whole in the Yellow River Basin, but there is some deteriorating trend in some sub-regions in August. (2) With obvious differences in the 16 sub-regions, the higher annual values of NDVI occur in the Taohe, Yiluohe and Weihe sub-regions, while the lower in the indraft area and the Lanhe sub-regions. The spatial changes of NDVI are unanimous with precipitation in most part of the Yellow River Basin, and the average changing rates of NDVI in different sub-regions are different. Finally, the relations of NDVI between precipitation, runoff and runoff coefficient in every sub-region are researched. The results show that NDVI has some apparent positive correlations with precipitation and natural runoff within a year, and furthermore, NDVI has some time lags behind precipitation. From the perspective of inter-annual changes, NDVI has some positive correlations with precipitation, but has complex relations with natural runoff and runoff coefficient variability. There is no, if any, obscure correlations between them.