In this paper,some principles of automated generalization on the discontinous area phenomena-were discussed,followed by the strategies of auto-generalization.Furthermore,the authors expounded the algorithms of every operation of the figure auto-generalizatio of areapatch,i.e.,selection/elimination,simplification,exaggeration,displacement,and aggregation.Finally,the implementation methods of the above algorithms,and the operational workflows of a few cartographic feature,were reported.

Quantitative studies of the relation between weathering and time suggest that the rates of most weathering processes decrease with time. Some weathering processes appear to conform to exponential function of time.Based on this theory,we can estimate ags of landforms based on the analysis of rock-weathering rinds.This relative-dating method has been used for several decades since 1966.Recent studies of weathering-rinds on sandstones in the middle of Hexi Corridor in western China suggest this method is applicable.The authors have reviewed the development of this technique.

On the basis of the" atlas of yearly dryness/wetness in China for last 500-year period",the time series of floods in the Huaihe River Basin during 1470-1991 are established according to the flood index which considers the contribution of different flood area and different flood grade. Some characteristics of floods including statistical features, time series features and fractal features in the Huaihe River Basin for the last 500-year period are analysed according to the flood series. The analysis shows that the floods in the Huaihe River Basin have a relatively high frequncy and also have the features of simultaneous occurrence and successive occurrence.They have the periods with different time spans which are about 460-year,150-year and 60-80 years and some shorter time span oscillations.They also have time fractal featues in some scalling ranges. The time fractal dimension is decreasing with the increasing of the flood grade.It is inversely proportional to the periods of floods and may become an importment parameter in the study of floods.

The purpose of this paper is to clarify the internal life-space structure in Chinese cities,by a case study of Lanzhou,the capital city of Gansu Province.A special attention is paid to DANWEI(or working unit),a principal territorial form of the urban life in Chinese cities.The formation,the roles,the daily-life patterns,and the distributive characters of DANWEI are considered.It is clarified that the internal life-space structure in Chinese cities is composed of three levels(Fig.4):the basic life-space as DANWEI,Which is related to both the works and residences of the citizens,and influences on the urban land-use pattern as well as the social area structure;the low-level life-space which is composed of the homogeneous DANWEI; the high-level life-space which is the Municipal District.This internal life-spacestructure in Chinese cities is formed through the administrative control and the residentialPlan of the Municipal Bureau(Fig.5).

The water area of the South Channel is wide,the volume of the water body is large,thedynamics is strong,and the content of suspended sediments is higher.the sediments consist of fine-grained sediments mostly.The water has high capability of transporting,diluting and clearin.The pollutants of the South Channel are absorded mainly by sediments.They go there and back during empting to the sea.They are circularly transported and transported towards bottom,flats,flood channels,and accumulated at the places between the river and the sea.

The developing of Chengde Area in modern ages arised under special historic backgrounds. The economic developing of this area was greatly prompted by large amounts of migrations out of the passes and the emerging of the Summer Mountain Mansion,which was the political center outside the Great Wall.The regional features and the process of economic developing in Chengde Area are studied In the two consequent stages with the clue of the rising and decli ning of summer Mountain Mansion. It is also elucidated that the declining of the Mansion had affected not only the economic development of Chengde City itself, but also the economic geographic appearance of the whole region.

The development of the mouth bar is Influenced by the boundary conditions of the river mouth,runoff,oceanic power,sea level change and channel dredging. The mouth bar,taking shape of fan,is composed by closely compacted sands.In 1984-1987 in natural situation,the Yellow River mouth bar was over 7km in length,with its top at an elevation of -0.1m-0.5m,and it moved seaward at a speed of 1.30km/a.In 1988-1992,the mouth bar was dredged,its length decreased to 4-6km, and its top was at an elevation of -0.6m at an average,and the rate Of Progression was 1.26km/a; therefore the Pressure Of laborious flood control in the reaches of the river mouth was alleviated.

This paper discusses in detail the principles and methods for the design,management,and economic appraisal of contour hedgerow projects.The authors claim that functions of the designed hedgerow should be constrained to avoid contradictions between its ecological and direct economic benefits,hedge plant properties should be emphasized in species selection,the major Purposes of hedgerow management are to promote hedge formation and to minimize negative effects of hedgerow on field crops,a cost/benefit analysis Is appropriate for both ecological and economic assessments of contour hedgerow projects.

In this paper,the integrated analysis of multi-spectral,and multi-temporal remote sensing image data(TM,MSS,NOAA/AVHRR) and geoscience data(geomorphological, hydro-geological,lithofacies,archaeological) have been carried out to identify paleo-coastal lines since the Holocene Epoch in the eastern part of North-China plain. The emphasis of the study is placed on the utilization of Information reflecting spatial distribution of salt groundwater and changes of water chemical components,which are closely related to paleo sea transgression and are reflected by environmental factors such as water,heat,salt,soil and vegetations.Some image processing methods are used,so as to better reflect the combined landscape features of soil salinization-vegetation-landuse-geomorphy.Further,integrated processing for images concentrating thematic informations has effectively enhanced the differences of landscapes,for two sides of transgression boundary in the Holocene Epoch.Finally,supported by GIS,a variety of thematic maps are digitized.On the basis of spatial registration,an integrated dataset is generated and used for synthetical analysis for defining and verifying the paleo-coastal lines.

Based on a great amount of chemical analytical data of the Natong weathering redearth curst in the Nanning basin and the Jiangze Weathering redearth Curst in the Baise basin in the Zhuang Autonomous Region of Guangxi,this paper carried out a comparative research on the confirmation,formation,distribution and soil fertility of the Quatarnary redearth and the characteristics of the two weathering cursts by using the indices got from the intensity of geochemistry and the coeffients of silica ferrite and silica alumina, and discussed the developmental process of the weathering curst and its impact on the environment.

Chinese folklore geography regarded as one of promising subjects in China. It is an endless and complicated development process.The paper summarizes three periods:ancient,modern and contemporary.It is a subject which studies Chinese folklore area system and the relationship with geographical environment.It is also an important branch of humanities geography,and is the subbranch of culture geography.It has some characters,such as area,synthesis,edge,history,variability and society.The purpose of studying Chinese folklore geography is to push society forward and to develop geography science.This subject studies not only the folklore characters and its evolution and the distributing principle of every nation and social group,but also the various relations between the folklore culture and geographical environment and the characters of folklore geographical area system.

This essay discusses the implications of famous historical cultural cities,indicates the characteristics of spatial distribution of famous historical cultural cities in China,sets forth the ways of classifying famous historical cultural cities. The essay divides ninety-nine famous historical cultural cities into six types.It also analyses the main characteristics of every type,discusses the roles and functions of famous historical cultural cities in protecting cultural relics,urban constrution on historic sites,development of tourism and civilization,and provides some suggestions to city construction and development of tourism.

Earth system science should not be accepted as a pure science which cannot survive beyond itssocial context.This paper first provides a systematic view interpreting the architecture of earth system science.which has global change studies and regional sustainable development being its ‘start’and ‘end’ points between which the linkage is established by two other orderly phases:regional modeling and macro-regulating information system.It is suggested that research into global change be strengthened in terms of the differentiation of regional physical environment and social progress.and that macro-regulating information system thereupon be employed to reveal the interaction between the global and regional levels of the earth system.Particular emphasis is then given to regional sustainable development──the objective of earth system science studies.

The Industrial Zone of Yangtze Valley(IZOYV), with 40% of the country's total population and GDP, is a key area for national economic development in China.IZOYV is facing some serious problems in its future development.and among which energy supply is the most serious one.With 1% of China's energy proved resources.the energy consumption of IZOYV in 1994 was 32% of the country's total, comparing with that its primary energy production registered 18% of the country as a whole.As a result, the recent energy sufficiency of this area is only about 60%,and it is estimated that the amount in imported energy will reach nearly 400 million tones in 2020.Considering the spatial disparity in energy production and consumption in this area, such a huge energy supply will cause a greater pressure on energy transport, particularly on the railway system.What is more.the great increase in energy consumption dominated by coal (more than 74% of the total energy consumption) will make the environmental problems worse.

The variation of solar radiation in China during the recent 35 years(1957-1992) is analyzed with variance technique and significance test(F_α=0.05).The results show that,direct solar radiation has obviously decreased in the whole county since the 1970's,with the maximum value of decreasing occured in the Yangtze valley.The trend of diffuse solar radiation showed regional features:increased in the Northeast,North China and the south of China,decreased in the Yangtze valley and the Northwest.The annual amounts of direct and global solar radiation of the whole country are decreasing at a rate of 246MJ/m²· 10a and 16.8MJ/m²· 10a respectively.In addition,among the available regions,the typical distribution characteristics of seasonal variation of solar radiation are classified into four types.

The unification of Remote Sensing(RS) and Geographic Information System (GIS) is the tendency of the development of science and technology.Remote Sensing Image Map(RSIM) is a new type of map with the RS image as foundation,according to certain mathematical regulations and map scale, comprehensively contracting the thematte map information and geographical base information on the plan of earth surface image.to reflect the geographical distribution and relationship of resource, environment, society and economy phenomena.The compilation of RSIM needs the GIS as the tool unified with RS processing tool.This paper introduces the research and experiment on the compilation of remote sensing image map(RSIM), based on the GIS and RSIM map-making software CITYSTAR; depicts the key technologies and working procedure:at last, takes Xiamen and Dazhu as two case studies to tell readers the detail methodology and process of compiling the RSIM.This research is mainly to reach the target of the whole procedure of making the RSIM on the computer system based on the personal computer and Chinese environment.Here the key issues are the transformation of vector data of some geographic information an dthe image raster data.as well as the mergence of the two kind of data.We also solved the data exchange problem with the softwares like ARC/INFO, INTERGRAPH.MAPINFO, MAPCAD and so on.In this paper the method of making the large scale(1:25.000) remote sensing image map is also discussed.

Border trade, as an important component of the implementation of opening up in China, has achieved a great progress.The border areas that were in relatively closed status in the past, have been changed significantly in terms of population flow as wen as material and energy flows.A series of environmental problems occurred in the course of development.In this paper, Hulun Buir League in Inner Mongolia Autonomous Region has been taken as a typical study area.The strategies for coordinating border trade and environment protection so as to attain the objective of regional sustain able development have been studied.The main points are as follows:(1)At the ports, environmental management should be strengthened.Effective measures for goods examination and biological quarantine should be established on the basis of relevant laws and regulations of the country with consideration of local conditions.Trans-boundary transfer of pollution in all forms should be strictly prevented so as to ensure environmental safety of the border areas.(2) In the process of urbanization of the ports, comprehensive environmental renovation should be conducted so as to prevent pollution pollution.It is especially significant to protect water resources.Countermeasures in this respect include:reasonable utilization of surface water; preventing ground water from over-extraction; purification of contaminated water through combination of waste water treatment plants and oxidation ponds; control of the relatively high concentration of fluoride and mineral contents in groundwater.The protection of water environment should be the major part of environmental investment.(3) In the process of constructing export commodity productive bases.it is important to protect the environment and maintain benign ecological cycle.Countermeasures for development of eco-agriculture, protection of grassland, and prevention of lake eutrophication should be conducted.By adopting quality control of the whole productive process, production of green products for international markets can be developed.(4) International cooperation in the area of environmental protection should be carried out along with the development of border trade.

In this paper.We concentrate on the study of the possibility of the usage of tree ring Image Analysis in the climate change research during historical time in Kangding area of Sichuan Province,with Picea balfouriana sampled from West Sichuan Province.Image analysis is a new method used in dendroclimatology with the reflected brightness (defined as Gray Value) as climate change indicators.There are ten different parameters, which include three ring width series and seven gray value series.got from image analysis.Twenty samples of eleven trees are selected by correlation analysis to be used in chronologies.The research period is 1950-1992.there is almost no difference between the ring width series derived from image analysis and from ring width measurement instrument.So the series from image analysis can be used in the comimg research.The relationship between the series of gray value parameters is not as close as that of the series of ring width parameters.Ten chronologies is built.Divide the seven Gray Value chronologies into two parts:on is the Maximum Gray Value, Early Wood Gray Value and Tree Ring Gray Value; the other is Minimum Gray Value, Ratio Between Maximum and Minimum Gray Value, difference Between maximum and Minimum Gray Value and later wood gray value.Relationship between the chronologies in part is closer than that of different parts.Four monthly averaged climate factors (precipitation,temperature, maximum temperature and minimum temperature) are used in the analysis to discover the relationship between the chronologies and climate change.It is shown that changes in ring width chronologies are closer to that of yearly precipitation, and the correlation coefficient is 0.42.Changes in gray value chronologies are closer to that of monthly averaged temperature parameters.especially the relationship between the March-april maximum averaged temperature and the minimum gray value, gray value ratio, gray value difference, three ring gray value and later wood gray value.The correlation coefficients between is -0.58.-0.56.0.53, -0.51 and -0.58,respectively.So.we can see that more useful data are derived from image analysis.and more information on the climate change during the historical time will be derived from the analysis of these data.

Discrepancy and balance are two developmental goals which must be taken into account.The discrepancy is the inner motive force of economic growth, and also is the way to balanced development.By analysing the alteration of provincial discrepancy combined with the increasing speed, this paper indicates that there is a relation between them.During the earlier stage of provincial discrepant process.the total economic amount is limited.Only the superior area can be invested concentratively so that the speed increases quickly, which enlarges the provincial discrepancy.During the later stage, discrepancy surpasses the provincial bearable capability and turns to be an obstacle.The speed drops down and discrepant controlling becomes the most important task.so only proper discrepancy can coordinate the contradiction between them.After establishing a functional relation, the interaction and the dynamic changing trends were revealed through an approachable model, directed by the appropriate discrepancy, a warning level can be set up to make a policy for discrepant adjustment.An example proved the method.When shandong'S maximal discrepancy of GDP per capita arrived at $ 7028.6.it got into the warning state and gained the maximal speed of 19.05% per year.If discrepancy is small.the concentrative developmental policy should be adopted to pick up the speed.When it is getting large and approaching the warning level, discrepant controlling should be adopted to rationalize it.

The Liujiangang Harbor is located at th Lou River(in River) Mouth,at the northeast of Taihu Plain and on the south border of Yangtze Estuary.In the Early Ming Dynasty which selected Nanjing as its capital,the Tiemuer Empire was rising in the Central Asia and the Silk Road was hindered at that time.The Ming Dynasty had to over again open up the Maritime Silk Road to develop foreign trade.Before the Middle Yaun Dynasty,the historical record Showed that sediments were deposited in the Lou River.The water depth in the channel was getting shallow,and it is difficult to built harbour and navigation Channels.Owing to the fact that in Ming Dyansity the Lou River was regulated, the water depth for harbour and navigation was improved.In the short Perid of the Early Ming Dyansty the Lou River had the best coditions for builting harbours in the region of the Yangtze River.The facts mentioned above resulted in the flourish of the Liujiagang Harbour which became the departure harbour of Zheng He's sailing to the west Ocean.In the Middel Ming Dynasty,the south bank of the Yangtze Estuary collapsed because of erosion by water flow and tide,and the Liujiangang Harbour and the Liujiahe Town were collapsed.At the same time,the Lou River had a serious deposition.Zheng He's sailing to the West Ocean was ended.In the Middle and Later Ming Dynasty,the coasts of China were barassed by the Japanese pirates,and the Grand Canal was repaired and reopeaned for water transport.All these led to the declining of the Liujiagang Harbour.

In this paper,foreign World-city Hypothesis and China's experience about developing international cities are briefly reviewed,and the possibilities and the major lixmting factors for China to develop world-cities are analyzd by following the theoritical framework of world-city hypothesis.Besides,a preliminary evaluation on the present situations and the prospect of potential world-cities inChina is given.

Barrow is located on the arctic coastal plain at the northeast Alaska (71°20'N.156°40'W),where Permafrost is well developed with a mean annual temperature of -12.6℃.Therefore, the modern environmental processes are dominated by physical weathering (freezing and thawing) and segmentation which infuence on the characteristic of present tundra environmental geochemistry.Some 35 samples of water, soil and snow were collected from sea, lagoon, lake.stream and bog at Barrow in August-September, 1994.The preliminary results are as follows:(1) Chemical and bio-chemical processes also existed in such an extremely cold region, which may be caused by higher summer temperature.(2) H⁺ is a typomorphic element appeared in the Arctic tundra environment.(3) The major positive and negative ions are K⁺⁺Na⁺ and Cl^- in the aquatic environment, appearing in a distribution roder of decreasing from ocean to land, that is:stream water2+ is extremely high which ranges from 73.87% to 90.41%,and the contents of rare elements.rare-earth elements and trace elements are relatively low.However, the contents of Hg, Cd, Cr and comparatively high.

There are many bay-drowned-valley tidal inlets and Sandbar-lagoon tidal inlets in Hainan island.This paper selected two tipical deputies──Yanpu Bay-drowned-valley tidal inlet and Sanya sandbar-lagoon tidal inlet, analysed and compared their geomorphological structure and surface sedimentation.and got some conclutions:(1) The difference and the similarities of developmental models about bay-drowned-valley tidal inlet and sandbar-lagoon tidal inlet:(a) The bay-drowned-valley tidal inlet system has three geomorphological units──tidal inlet and its flood tidal delta, ebb tidal delta.and so does sand bar-lagoon tidal inlet system; (b) The developmental scale of bay-drownedvalley tidal inlet is greater than that of Sanya sandbar-lagoon tidal inlet; (c) The developmental coefficients of flood tidal delta and ebb tidal delta of Yanpu tidal inlet are 0.12 and 0.44 respectively,those of Sanya tidal inlet are 1 and 2.8 respectively.(2) The difference and similarities of sedimentary models about bay-drowned-valley tidal inlet and sandbar-lagoon tidal inlet:(a) In Yanpu baydrowned-valley tidal inlet, the grain size of sediments in tidal inlet is smaller than that on ebb tidal delta and flood tidal delta.In Sanya sandbar-lagoon.the grain size of sediments is greater than that on ebb tidal delta and flood tidal delta; (b) The grain size of sediments on all geomorphological units of bay-drowned-valley tidal inlet system is smaller than that of sandbar-lagoon tidal inlet system;(c) The heavy mineral contents and ZTR of sediments in Yanpu bay-drowned-valley tidal inlet are higher than those in Sanya sand bar-lagoon tidal inlet:(d) The heavy mineral combinations of sediments on bay-drowned-valley inlet and its ebb delta and flood tidal delta are different.The heavy mineral combinations of sediments on sandbar-lagoon tidal inlet and its ebb delta and nab tidal delta are the same; (e) The foraminifer genus-Ammonia and Elphdium are common in both of the two type tidal inlets; (f) The sediments of Sanya Yuzan stream outlet have many Nummulites and Cellanthas, but that in the Yanpu area has no such materials.(3) The stability of bay-drowned-valley tidal inlet in better than that of sand-bar-lagoon tidal inlet.

The theory of regional system is a theoretical base for regional development and study.According to the results from the study project of "study on the Regional Development in the mountainous areas in Beijing",this article discusses the five main contents─structure and mechanism of the regional system,polarization and diffusion of regional process in regional system,regulation of regional system,classification and comprehensive regionalization in regional system and study methods.Only by stregthening the theoretioal study of the theory of regional system,can the regional development be improved to a new level an can the process of geography modernization be put forward.

This paper discusses Marco Polo's contributions to physical geography and mineralogy.Macro Polo correctly explained the rise of ignition point for short of oxygen and severe coldness on high mountains and firstly observed and recorded the phenomena concerning boiling point in the world.He explicitly recorded the Arctic region and the Arctic inhabitants on the basis of on-the-spot tour and correctly made the earliest description in the world about the polar night and polar day.And he was the first and the earliest representative among the civilized peoples who reached, proved, discovered and recorded the Arctic ocean.Marco Polo also described and recorded the improtant.Mineral phenomena and the ways in which the local People mined and utilized those minerals.All of these were seen by himself, leaving the precious historical data.The most improtant minerals put down by him included:Petroleum, natural gas, coal and asbestos ets.So he took down a sect of mankind's course fo exploiting those minerals and spread the knownledge concerning mineralogies.Thus he and his travels stimulated the Europeans to know those minerals, and he also left the precious data about mineralogies and about opening up the mines.

It is of great important to take the young scientists into consideration when the scientific and technological rewards if firstly established by the China Society on Qinghai-Tibet Plateau.This paper will discuss two issues concerning the function of youth in the process of the scientific development.1.Growth of the young scientists With the great ambition and right direction,young scientists should learn more new knowledge and study more new ideas by fully using their superiority,such as having courage to make innovationa,boldness in discovering and great responsibility.In the new time of "Rejuvenating China by applying scientific and technological advances", the study on the plateau has entered a new period.In this situation, more young scientists are needed to be the main force in the development of Chinese sciences.2.Study of the Qinghai-Tibet Plateau in the 21th Century The organized muti-disciplinary investigations with many achievements have been made since 1950s.Based on the "Eighth five year Plan,National Climbing Project",serveral imPortant reresearch fields have been pointed out:such as the study on the earth dynamics of lithosphere on the plateau,the Qinghai-Tibet Plateau and Global Change-effect and respones,and the study on the regional sustainable development on the plateau. It is a new period for the study on the plateau,with following characteristics: The study on the Qinghai-Tibet Plateau will be a global study, it will enter the best state,and it will develop under the policy of "rejuvenating China by applying scientific and technological advances".The present study on the plateau not only has the global significance and regional significance, but also has a favorable impact on society.At present,the study on the Qinghai-Tibet Plateau needs young scientists to be the backbones for its deepgoing.

Drought is normally defined as water shortage caused by the imbalance between water supply and demand.The fomation and intensity of drought are gradual cumulative processes.A new drought index considered the effect of rain shortage of early days is given in this paper.Three grades of drought:moderate,severe and extreme drought are divided.On the basis of the data of drought during 1951-1991,we analyse the area distribution of drought, including frequently-occurring drought.serious drought and continued drought. Based on the number of drought occurrences and an analysis of the average number of drought months,regional differences in drought oc currence are notable.The result shows that there are four large drought centers in China.It is shown from the time series of drought index that there is a linear tendency of drying in the whole country and in most areas.They are the Huang-Huai-Hai Plain region.the south China and Middle and Lower Yangtze River Region,the Southwest China Region and the Western Part of Northeast China Region. Using the time series the drought-affected area and the drought-damaged area in whole country,the impacts of droughts are discussed at last.The periodicity of drought-affected and drought-damaged areas in China has been significant in the last 40 years. During this time,three wet Periods and three dry periods occurred.The periods of 1958-1962,1971-1981,and 1986-1988 were observed as significant drought periods(i.e.,more than 20 million ha were affected).During the Periods 1950-1957,1963-1970,and 1981-1985,less than 20 million ha were affected.In total,seven severe drought years(1959,1960,1961,1972.1978,1986 and 1988) were recorded during the significant drought periods.In each instance,the drought-affected areas encompassed more than 30 million ha.The variability in the occurrence of drought-affected and damaged areas seems to increase during the last 40 years.Averaged by decades,the drought-affected areas in China from the 1950s to 1980s are 12.6,21.7,26.1 and 24.1 million ha,respectively.This trend is consistent with the general trend of summer aridization in China.It is concluded that there are periods with large drought-affected area and large drought-damaged area,and there is also a linear increasing tendency with the fluctuation.

On the background of the planning economy and in the urban-rural separation system with a development model of heavy industry bias,China preferred to control large cities and to develop small cities.In 1980's the government of China outlined the urban development policy:"to control large cities,to moderately develop medium-sized cities,and to actively develop small cities." However.the actual development has been quite different from the demands of the policy:large cities and small towns have developed rather fast,but medium-sized cities have developed slower.Analyses have indicated that urban developing prospect cannot rely on urban scale.Moreover,the demands of the present Policy do not correspond with the development of market economy in the period of opening and reforming.It does not fit the national conditions of limited land and large surplus agricultural labour forces.Therefore,the policy of urban development should be adjusted.The ideas suggested include:To develop large and medium-sized cities with the improvement of urban modernization,and to set up urban feedback functions to regulate the industrial and population capacities by the means of tallying the value law of market economy.To develop small towns actively and rationally throught the advance of their planning and management.The quality of living and investment conditions of small towns should be improved to form a centralized distrbution of rural industry.On account of obvious regional disparities in China,urban development should follow different mdels in different regions so that urban expansion and distribution can correspond to special regional conditions and economic development.

Chinese coal industry is one of the important pillar industries of the national economy.It is the major guarantee for the economic sustained development in China.But,a large size exploitation of coal resources causes land destruction and environment degeneration,aggravates contradiction between increasing population and decreasing land area,and hinders national economic sustained development.Through practical survey and comprehensive analysis,this paper studies the trends of China's coal exploitation and its influence on land resources,discusses the major degraded land types,the area and distribution of the coal mining fields.According to the demands of the market economic development,the principles of land restoration in the coal mining fields are pointed out,i.e,the man who destroies the land must resume it.Suitable measures to local conditions should be found and the problem should be tackled in a comprehensive way.Both economical,social and ecological benefits should be considered.Land use plan and coal mining exploitation plan should be combined.On the basis of these.four main directions of the coal mining land restoration are put forward:(1) agriculture,forest,stock raising and fishery,(2) mining industry and road tion,(3) residential area,(4)tourism,recreation and sanatorium. Furthermore, this article also studies the models of agricultural land restoration and relevant techniques related to engineering,irrigation and biology,and evaluates the economic benefits of land restoration in the coal mining fields.Briefly describes the characteristics of land destruction and methods of land restoration in the different regions of China.

Two drainage patterns are found in the North China Mountains:One is a longer river system across the ranges of the Taihang Mt.and the Yanshan Mt,it initiated in the Eocene.the first episde of the Himalaya Orogenesis,and subsequently passed through the primary stage of formation in the Eocene,and lateraly windening stage in the Neogene.The internal drainages coexisted with the exterior draginages from the Early Pleistocene to the Middle Pleistocene and the lateral continuity stage was in the Middle Pleistocene.The river incising and modern drainage forming stage was in the Late Pleistocene.The other is a shorter river system origined from the east pedimont area of the Taihang Mt.and the south pedimont area of the Yanshan Mt..It started in the beginning of the Early Pleistocene,the third episode of the Himalay Orogeny,and subsequently went on incising stage in the Early Pleistocene,lateral windening stage in the Middle Pleistocene,rivers dissecting and present drainage forming stage in the Late Pleistocene.Comparing the two drainage systems,there are two different valleys in the river geomorphology.The former has a three series supPerposition-tray-like valleys,broad valleys with "U"-like and"V"-like gorges.The later has a two series superposition-broad valleys with "U"-like and "V"-like gorges.

Based on the observed data during the 1985-1990 period from the evaporation observing station of the Nansi Lake in Shandong,this paper discusses the surface evaporation in the Nansi Lake.The conclusions are as follows:(1) Water surface evaporation has a linear relation to the difference of vapor pressures,the difference of vapour statuations in the air,and the temperature of water surface,and has a inverse relation to air pressure.It is also related to wind speed.(2) When the depths of water are the same,water surface evaporation has a inverse relation to the 0.041 times power of the diameter of round evaporation surface.(3) When the areas are the same,water srface evaporation has a inverse relation to the 0.048 times power of the water depth during April-August.and a linear relation to the 0.151 times power of the water depth in September-November.(4) When the same type of evaporimeters are used,the evaporation from the evaporimeter with a double layer tank(GGL-3000) is 8.6% greater than that from the evaporimeter with a single layer tank(E-601),and is 5% smaller than that from the evaporimeter with tubes.The evaporation from the evaporimeter made of irons is 4.3% greater than that from the evaporimeter made of glasses.(5) With the same evaporimeter,the annual average evaporation is 21.2% greater when it is above the ground surface compared to that when it is buried,and is 15.4% greater when it is above the ground surface compared to that when it is halfly buried.(6) The evaporimeters of E-601 and GGL-3000 have the smallest differences to the 20m² evaporation tank, and the 20cm evaporimeter has the largest difference.(7) The average annual water surface evaporation in August is the largest in a year,and that in January is the smallest.(8) Seasonally.summer has the largest evaporation,making up 35.9% of the total in a gear.The minimum value occurs in winter.The maximum and the minimum annual evaporation have a difference of 168.3%mm and a ratio of 1.22.This indicates that the variation of evaporation in different years is not obvious.

The market,traffic and service region of agricultural products are three compound factors of the purchase-sale network of urban agricultural products.They constitute a multilayer and netted spatial structure.The market is the collection-dispersal center of agricultural products and the core of the service region.Its scale and distribution not only restrict the flowing direction and volume of agricultural products,but also affect the spatial characteristics of service region.So the adjustment of the scale and distribution of agricultural products market is an important content in the optimization of the spatial structure of the purchase-sale network of urban agricultural products.