Chinese geography has acquired proud progress, representing the breakthroughs of scientific researches, contributions to national construction, innovation of research means, contributions to science and education, proffers for society and so on. Yet, such problems as weakness of basic research, insufficiency of subjects conformity, wrong path of academic tend, worry of competition capacity, deficiency of global perspective and inaccuracy of geographical education orientation, exist in recent Chinese geography. International geography is paying more attention to key study issues identified by scientific community. On the other hand, scientific community is more appreciating the contribution of geography and its perspective to scientific knowledge. The scientific issues concerned by geography orientate the urgent demands of present decision-makers. In various manners, geographers make more contribution to solving practical problems. The recent international geography focuses on the following points: to reveal the imbalance and dynamics of complicated systems; to understand the tide of globalization (including environment, economics, population, society and culture) and its impacts; to establish series research on special continuum from local to global; to take comparative studies on processes by means of vertical data including temporal series; to strengthen influence of geographical theory, technology and research fruits on decision-making; to reinforce geographical education including enhancing the geographic ability of public; to improve training of geographers in university; to advance geographical understanding; and to intensify geographic organization and institution.
In the near future, industrial optimization and promotion, agricultural development, the development of high-tech industry, international trade, urbanization, population health, the integrated utilization of natural resources and social sustainable development, the optimization of energy structure, environmental improvement and national security in China all demand geography to contribute much more. So Chinese geography should orientate the national demands for solving the important geographical issues in national development. It should strengthen basic research and occupy the front position of international academia in some main key aspects. The geographical advantages of China should be fully brought into play and the geographical science with Chinese features should be developed. The present bases should be integrated and enhanced. The strategic emphases of Chinese geography are as follows: to research the evolution and dynamics mechanism of the earth surface system by means of synthetic view and disciplinary cross; to innovate theoretical system; to develop integrated and regional methodology of geography, to exploit the research way of coupling patterns and processes, to develop geomatics and digital earth, to promote geographic experiment; to organize cooperation projects of science and technology; to strengthen the obtainment of the firsthand data; and to make breakthroughs in such applications and technological researches as territorial management, regional sustainable development, global change and its regional responses, geographical information application, etc.
Studying impact of the happened climate warming to the crop yield is an effective approach for understanding the impacts of climate change on agriculture. In this paper, a new method is put forward to calculate climate yield with a climate trend, which may overcome the disadvantage of traditional method. In the new method, a referenced period that satisfies the hypothesis of traditional method is selected to construct a function on the main meteorological factor and climate influence coefficient by regression. This function can be used to calculate climate influence coefficient of other years. Rice yield in Heilongjiang province is mainly restricted by temperature. A case study on contribution of climate change to rice yield change from 1952 to 2000 is made in this region. The result shows that, although non-climatic forces have likely dominated the trends in per unit area rice yield in Heilongjiang province, the impact of climate warming on rice becomes more and more prominent during the past 20 years. The real rice yield per unit area in the 1980s is 30.6% higher than that in the 1970s. The increased yield due to climate warming is 12.8%-16.1% of the real increased yield. The real rice yield per unit area in the 1990s is 42.7% higher than that in the 1980s. The increased yield due to climate warming is 23.2%-28.8% of the real increased yield.
Based on a literature survey of 22 lacustrine sediment records from the Tibetan Plateau, its northern adjacent region--Xinjiang, and equatorial Africa and northern African area, and 18 loess-palaeosoil profiles from the Loess Plateau and the Tibetan Plateau, the paper analyzes palaeocliamtic oscillations in Asian and African monsoon areas since 40 kaBP. The result indicates that lakes status records and loess-plaeosoil records showed regionally similar patterns of climate changes over the last 40 ka in Chinese monsoon areas and African monsoon area. These areas, at 40-24 kaBP and 12-4 kaBP respectively, corresponding with high insolation of precessional cycle at summer half year, experienced moist climate regime. In the Tibetan Plateau and its northern neighbor, Xinjiang area, at 40-24 kaBP, with highest lake level, the greatest lake area and several lakes groups came into being for lake water overfall between adjacent catchments over the last 40 ka, moister than 12-4 kaBP, which was called by many pioneer research workers of the Tibetan Plateau, the pan-lakes regime. However, in the Loess Plateau and African monsoon region, there occurred a converse evolution of climate change: it was wetter at 12-4.0 kaBP than 40-24 kaBP with the culmination of wetter condition appeared at 10-6.0 kaBP. 40-24 kaBP, a particular period for the Tibetan Plateau, for high insolation in summer over the Indian Ocean, the Indian monsoon was very strong and higher sea surface temperature occurred on the West Indian Ocean.
This paper conducts comparative studies of the distribution of pre-history culture in eastern Qinghai. The result shows that Qinghai pre-history culture has expanded in this space gradually. The noteable expansions occurred twice and at the same time the pre-history culture expanded from east to west gradually along the Yellow River valley and the Huangshui valley. The distribution of eastern Qinghai pre-history culture positively related with temperature. Especially, it has a close relationship with the accumulative temperature of daily mean temperature above 10oC. The changes of pre-history culture and the climate are identical with each other. It has proved initially that the development and expansion of pre-history culture are positively correlated to the climate change. The change of climate is the root cause for this change. So the climate is the inducement of the Qinghai pre-history culture vicissitudes, and it exerts great influence on the distribution, spreading, expansion, enlargement and development of the civilization.
Based on the climate data of 77 meteorological stations covering 1958-2001 in northwestern China (the area is within the north of 35oN and west of 105oE in China), and using the integrated Penman formula, the mean potential evapotranspiration (PE) in our study area is calculated. Four patterns of variations of PE and precipitation were detected, showing that the solar radiation and wind speed are two main reasons responsible for the evaporation in the arid area. The aridity index is defined to the ratio of PE and precipitation and is used to describe distribution of the wet-dry conditions in northwestern China. The linear regression trends of the aridity index for the last 50 years show that there are a drying trend in spring and a wetting trend in summer (pronounced only in east Xinjiang and west Gansu) over large parts of the arid areas, and a wetting trend in autumn in most parts of Xinjiang and west Gansu as well as north Qinghai, and in winter, part of the arid area tends to be wetter, and only parts of Xinjiang, Gansu and Inner Mongolia tend to be drier.
Recent studies indicate that widespread wastage of glaciers in western China has happened since the late 1970s, but diverse places under different climate settings have marked regional discrepancy as to the amplitude in glacier shrinkages. In the present study, we investigate the changes of glaciers at the head of Yurungkax river (centered at 35o40'N, 81oE) in the heavily glaciated West Kunlun Mts. by using aerial photos (1970), Landsat TM (1989) and ETM+ (2001) imageries. A comparative analysis performed for glacier length/area variations since 1970 in the West Kunlun Mts. shows that the prevailing characteristic of glacier variation is ice wastage, however, changes in glacier area are very small in this region. Results indicate that a small enlargement of ice extent during 1970-1989 was followed by a reduction of over 0.5% during 1989-2001. It concludes that the enlargement of glaciers during 1970-1989 might be caused by the decrease in air temperature and the increase in precipitation during the 1960s and that glacier shrinkage during 1989-2001 might be reaction to increase in air temperature, but abundant precipitation acts as a role of buffer in variations of surface mass balance of glaciers in the research region.
The Yili Valley of west Tianshan is located in semi-arid area of Northwest China. Tree ring increment cores were sampled for Picea schrenkiana from the upper and lower treelines of three sites, which present warm-dry, warm-moist and cool-moist climate patterns respectively. Six standardized chronologies were developed using a 60-year spline function, the correlation between tree ring-width and climate was analyzed. Comparison of chronology statistics among chronologies indicated that ring-width at the lower treeline showed stronger high- and low-frequency signals than those at the upper line. Correlation analysis showed that the growth of Picea schrenkiana was significantly sensitive to climate variations. However, there were different relationships between the tree growth and climate at different aspects of slope and altitude of the valley: tree growth at lower treeline on the south-facing slope was positively correlated (p<0.05) with precipitation in July and August during the current growing season, while at the lower line of the north-facing slope, tree growth showed a significant (p<0.05) positive correlation with monthly minimum temperature from November to January prior to the growing season, whereas there was no significant correlation between tree ring-width and climate variations at the upper line of both north- and south-facing slopes. These results suggested that different climate signals revealed in tree-ring width of Picea schrenkiana may be caused by the influence of topography: the variation of precipitation between the upper- and lower-treeline and the difference of temperature between the two aspects of the slope. In conclusion, there is not only precipitation signal but also temperature information in the tree ring-width of Picea schrenkiana. This dendroclimatological potential provides a possibility for past climatic reconstruction of both precipitation and temperature in this area.
The variations of alpine timberline altitude with latitude and longitude in China were investigated and their relationships with climatic indices were analyzed in this study. The results are summarized as follows: (1) The altitude of alpine timberline in China changes significantly along latitudinal and longitudinal gradients. North of 30oN, the timberline altitude decreases with the increase of latitude at the rate of 112 m per latitude degree. South of 30oN, the latitudinal change shows a different pattern: the altitude does not vary significantly with latitude in the eastern part and increases with latitude in the western part. The timberline altitude drops with the increasing of longitude at similar latitudes, resulting from increased temperature conditions from east to west due to large-scale topographic and geographic factors. The highest timberline (4600 m) was observed in southeast Tibet (29o-32oN, 94o-96oN), the highest timberline in the world. (2) The timberline is limited by growing season temperature, i.e. Annual Biotemperature (ABT) of 3.5oC, Warmth Index (WI) of 14.2 oC·month, and Mean Temperature for Growing Season (MTGS) of 8.2 oC. The corresponding altitudes of these temperature thresholds change with geographic factors, and this change has led to the changes in the latitudinal and longitudinal timberline patterns and timberline variations from the oceanic to continental climate. (3) Precipitation affects obviously timberline altitude at the middle-high latitudes in China; timberline is higher in arid regions than in humid areas at the similar latitudes, caused by increase of temperature at the low humid conditions.
Soil seed bank is the pool for species composition of a plant community. It plays a critical role in succession of the community and maintenance of the community structures and functions. In this paper, we studied the distribution of soil seed banks along an altitudinal gradient (1500-3500 m asl) on the southern slope of the Taibai Mountain. The main results are summarized as follows: (1) Reserves of the soil seed bank increased with an increase of elevation, reached its maximum at an altitude of about 2600 m, and then decreased with increasing altitude. Above the altitude of 2000 m, the distribution of seed reserves in the soil profile can be generally characterized by the fact that most of soil seeds occurred in litter-fall layer, and smallest reserves were in the subsurface soil layer. Below the altitude of 2000 m, most of soil seeds occurred in humus layer. (2) A total of 172 plant species from the soil seed banks were accounted in 21 plots. The number of species was reduced along an altitudinal gradient. The community characteristic of soil seed banks varied obviously in two altitudinal ranges, 1500-2500 m and 2500-3500 m. (3) The reserves and density of seed banks showed a similar pattern along the altitudinal gradient. It was better to use reserves to indicate the size of soil seed banks. In this study, the soil samples were divided into three layers: litter-fall layer, humus layer and subsurface soil layer.
To explore relationship between species richness and topography at a regional scale, topographical features, patterns of taxa (family, genus and species) richness and species density along elevational gradients, and relationships between degree of topographical variation, expressed as coefficient of variation(CV) of elevation, and species richness and species density in Hunan Province were studied by using provincial flora list and DEM (Digital Elevation Model) data. The results indicate that: (1) With an increase of elevation, taxa richness and species density increased first and then decreased, showing a unimodal pattern along an elevational gradient; and (2) with increasing CV of altitude, species richness and species density increased first and then decreased, namely, higher species richness and species density occurred at habitats with a moderate CV value.
Vegetation investigation and soil sampling of 14 sites, across the Gurbantunggut Desert along the range of 87o37'09"-88o24'04"E and in the range of 44o14'04"-45o41'52"N, were carried out. Eight species of low tree and shrubs, 5 of perennial herbs, 8 of annual plants, 48 of ephemeral and ephemeroid plants were recorded. These species of the plants occupy 1/3 species of Gurbantunggut Desert plant indices and their communities form vast patches of desert vegetation with great landscape significance. In the investigation we found that the vegetation communities are accordingly succeeded with the spacial variation of macro-ecoenvironment. On the basis of counting the frequency and important values, we chose Sinpson dominance index (C) and Herlbert diversity index (PIE) to describe the composition and structure characteristics of tree-shrub and herb synusiae. Using Principal Component Analysis (PCA) and Correlation Analysis (CA) we found that the micro-ecoenvironment heterogeneity of aeolian soil physio-chemical properties, such as soil nutrient, soil moisture, soil salt, pH, etc., only exerts significant impact on the diversity of herb synusia (PIEherb), with a negative correlation. Meanwhile, the micro-ecoenvironments, which take a form of antagonistic interaction, have composed a fragile equilibrium of the desert environment. In case this equilibrium is disturbed by artificial and natural factors, the ecological distribution pattern of Gurbantunggut Desert would change.
The distributive pattern and abundance of desert plant communities were examined in the lower reaches of Tarim river, southern Xinjiang. Eighteen species were collected within 18 sites along a sequence of groundwater tables in six transects. Except for Tamarix ramosissima and Populus euphratica, which were almost distributed across all sites, most of investigated species had low occurrence frequency in quadrats. Corresponce Ordination of a reduced dataset of 18 species revealed a separation of taxa into distinct groups corresponding to the different tables of groundwater. Clearly defined groups of species were strongly associated with three types of groundwater zones: shallow groundwater zones, intermediate groundwater zones and deep groundwater zones, ranging from <3 m, 3-5 m to >5 m respectively. Four distinctive taxa groups are identified corresponding to the three zones of groundwater table and the several major environmental factors. Canonical Correspondence Analysis (CCA) of the 18 species and seven environmental variables revealed that the most important factors associated with the distribution of species were groundwater table, soil moisture and soil pH value in the lower reaches of Tarim River. From a management standpoint, there is no reason to doubt that the most important factor for restoration of damaged ecosystem in this region is reasonable use of water resources in the whole Tarim river valley, especially in the middle and upper reaches of the river. This study confirms that the planners and managers of nature reserve in this area should take these major environmental factors and species characteristics into account in the process of decision-making.
Red tides are one of the main coastal catastrophic events of Guangdong Province, China. The comparison between the numbers of red tide events and the development indexes of cities along the coasts of the province shows that the regional differences in red tide outbreaks has a close relation to those in the coastal urban developments. The cause for an initiation of red tide blooms may be natural ones, but wastewater caused by the fast development of population, industry and aquiculture of the coastal cities enhanced the blooms. It may explain why the two periods of frequent outbreaks of the red tides from 1998 to 2000 matched the urban developments in the coastal areas of Guangdong not only spatially but also temporally. The red tides in the first period were restricted only on the coasts of middle Guangdong, where the urbanization were rapider than the other coastal areas of the province. In second period, fast increments in the development of the coastal cities in east Guangdong leaded to an increase in occurrence of red tides in the sea areas of the same coasts.
In this article, we mainly focus on the geochemical characteristics of stable carbon and nitrogen isotopes in order to trace the source and fate of organic matter in the Yangtze estuary and its tidal flat sediments. According to the features of physical geographical environment and the discrepancy in the effects of human activities in the study area, 12 typical sampling stations were selected along the Yangtze estuarine and coastal line. Based on the analysis of stable carbon and nitrogen isotopes in the tidal flat superfacial sediments from the Yangtze estuary, it was found that the ratios of stable carbon and nitrogen isotopes were respectively -29.80‰~-23.7‰ and 1.0‰~5.5‰ in the flood seasons, while they were -27.3‰~-25.6‰ and 1.6‰~7.7‰ in the dry seasons respectively, indicating that the seasonal distribution of discharges from the Yangtze River has significantly affected the seasonal variation of stable carbon and nitrogen isotopes in sedimentary organic matter. In general, the distribution of stable carbon and nitrogen isotopes revealed the mixing inputs of terrigenous and marine organic matter controlled the stable carbon and nitrogen isotope compositions in sedimentary organic matter. However, a series of physical, chemical and biogeochemical processes occurring in the local environments, to some extent, have the significant influence on the stable carbon and nitrogen isotope compositions in organic matter.
Yangtze Estuary Tidal Wetlands Environmental Information System (YETWEIS) is a comprehensive software system for environmental management and decision making in tidal wetlands of the Yangtze estuary. This software system was based on MapObjects COM technology, Data Mining technology, mathematics modeling method and Visual Basic language. It has many functions such as displaying, editing, querying, searching, spatial statistics and analysis, special decision map compiling, environmental qualitative evaluating. This paper outlined the system structure, implementation techniques, and facilities of YETWEIS at first. Then, it described the core modules of the software system--the special decision map compiling module and environmental qualitative evaluating model module in detail. At the same time it thoroughly discussed the environmental qualitative evaluation method, the method of calculating pollution indexes quality and environmental qualitative synthetic evaluation method based on information entropy. Finally, by using YETWEIS, this paper analyzed the heavy metal and persistent organic pollutants spatial distribution characteristics of the Yangtze estuary tidal wetlands in 2002, and provided a system assessment of Yangtze estuary environmental quality in 2003.
Some remnant marks of flood water level, characterized by dark color and with small eroded holes distributed on the horizontal level marks, are found along the hillside of Nanjing. The same features of the remnant marks of flood water level are also found on the cape of Caishiji cliff of Cuiluo Mountain. Detailed analyses on the altitude of the remnant water level marks and sediment grain-size collected inside the eroded holes and on the Yangtze River floodplain are carried out and comparisons with flood historical literature and modern flood water level records are made. Based upon which the following conclusions are drawn: (1) The altitude of the first and second ancient water level marks at 8.5 m and 9.5 m which exceed the modern Yangtze River water surface by 5-6 m are considered as paleoflood remnant because they have been disengaged from present Yangtze River water surface for a long time. (2) The altitude of the third ancient water level mark is 10.5 m, which is 0.3 m higher than the catastrophic flood in 100 years recorded in history. According to historical records of the Yangtze River flood, the level this paleoflood event may be equivalent to the level of a catastrophic flood in 100-200 years. (3) The altitude of the highest ancient water level mark is 12.8 m which is probably equal to the height of the paleoflood taking place in high sea level time of the Holocene.
In this paper remote sensing principle is used to explain the changing trend of different types of areas in Wuliangsuhai since 1986. It points out the general trend of total water area is increasing, that is, clear water area increased before 1987, decreased from 1987 to 1996 and increased again from 1996 to 2002. However, the case of giant water-grass area is basically opposite to that of clear water area; namely, natural reed area decreased before 1987, but increased after 1987; shallow water area and swamp area only increased slightly; and artificial reeds began to be planted in 1988, presenting an increasing trend in area year by year. Then we analyze the causes for all the changes, and expound the relationship between the changes of different types of areas and the parameters of hydrometeorological and water environmental factors. Finally, we discuss the technical means for sustainable development and perdurable utilization of water environment in Wuliangsuhai.
Based on historical data and remote sensing data, six indices including patch number, patch area, landscape dominance index, fractal dimension, patch density and connectivity index were used to analyze landscape pattern dynamics of water body in Kaifeng city since the end of the Qing Dynasty. The results showed: 1) Since the end of Qing Dynasty, landscape area of water body in Kaifeng city had experienced a process of increase first and then decrease from AD1898 to AD2002; the landscape dominant degree had the same change with the area. 2) Patch number of water landscape in Kaifeng city increased from AD1898 to AD2002, but the area of maximum patch, the area of minimum patch and the average patch area decreased, but patch density increased, resulting in an increase in landscape fragment degree. 3) Connectivity index decreased and fractal dimension increased from AD1898 to AD2002. The reasons for these changes include both natural factors and human factors. Prior to 1949, the impact of the Yellow River predominates and after 1949, the impact of anthropogenic activities play the leading role.
In this paper, the features of surface water balance in semi-arid regions of northern China were analyzed. These regions are located along the northern margin of East Asian monsoon region, where precipitation concentrates in summer and is mostly produced by convection system. Dry climate causes high potential evapotranspiration, most precipitation is exhausted by evaporation, and surface runoff accounts for only a small part. In winter, snow accumulates and melts fast in spring. Snowmelt flood and a summer flood display a double peak pattern of discharge route. In order to simulate the precipitation-runoff features in semi-arid regions, an Atmosphere-Vegetation Interaction model (AVIM) with detailed energy and water transfer processes between atmosphere, vegetation and soil was used. In this version of AVIM, runoff production caused by both excess infiltration and over saturation were taken into consideration and a snowcover model is involved. New schemes were validated for Xilin River basin and surface water budgets, and runoff generation and snowmelting processes were simulated well. The simulation results show the efficiency of new schemes.
Based on data from the Wudinghe River, a tributary of the Yellow River in the major coarse sediment source area of the middle Yellow River Basin, a study has been made of the effect of soil and water conservation measures on sediment yield in the condition of changing precipitation. Both annual sediment load and annual river flow show a decreasing trend with time, and the areas of soil and water conservation measures. The area-weighted annual and high-flow season precipitations over the drainage basin also show a mild trend of decreasing, less significant than the above variables. It has been found that specific sediment yield is negatively correlated with the areas of land terracing, tree planting and grass planting. The period between 1956 and 1969 and the period between 1970 and 1996 are taken as "baseline" period without measures and the compared period with measures, respectively. Comparison between these two periods indicates that, during the former period, the percentages of the variation in specific sediment yield, runoff to precipitation ratio and high-flow season water yield can be explained by the variation in precipitation were 69%, 80% and 77%, respectively. However, in the latter period, these percentages decreased to 26%, 31% and 54%, respectively. This change means that, in the latter period, soil and water conservation measures played a great role, and thus the contribution of the variation in precipitation to the variation in sediment yield was greatly reduced. Based on the 41-year data from 1956 to 1996, a multiple regression equation has been established.
Based on some discussions on the relationship between environmental capital and economic development, the social adaptive capacity coined by Ohlsson has been introduced. Combined with the classification of water resource management, the authors discussed the interconnection between the natural resource reconstruction and social adaptive capacity. With a view to overcoming water resource scarcity, increased social resources as an alternative way has been emphasized. At the same time, it allows strategic decision-makers to source some effective strategies from political economy system outside the natural resources themselves. To illustrate the effect of social adaptive capacity, a new social resource water scarcity index (SWSI) is developed based on a combination of traditional hydrological indices and our actual assessment index of social adaptability as most readily available proxy for social adaptive capacity. Calculations are made for 31 provinces, 2002. The study demonstrates that the index captures the social impacts of water scarcity more accurately than earlier indices. Finally, with a general concern that traditional technical and economic options for water resource management are no longer adequate for situations of increasing water scarcity. We pinpoint that there is a need to develop policy options to stimulate adaptive processes and strengthen social resources capacity, and consider and apply alternative multidisciplinary options based on critical social resource factors.
Based on regionalized variable theory, semivariograms of geo-statistics were used to research the spatial variability of soil properties quantificationally. The results showed that the semivariograms of soil organic matter were best described by spherical model, the best model for semivariograms of soil N and available K were exponential model and that of available P belongs to linear with sill model. Those soil properties have different spatial correlations respectively, the range of organic matter is the highest and that of available P is the lowest, and the spatial correlation of N and available K belongs to moderate class. Their spatial heterogeneity degrees were different too. The degrees of organic matter and total N were the highest, the degree of available K was in the next place and that of available P was the lowest. Influenced by the shape, topography and soil of the study area, all isotropics of available P were obvious in all directions while anisotropics of others were manifested. According to the analytical results, supported by GIS, Kriging and IDW were applied to describe and analyze the spatial distribution of soil properties. The results indicated that soil organic matter, total N and available K were distributed regularly from northeast to southwest, while available P was distributed randomly and its structural characteristics were not so distinctive as those of others.
The vertical variations of soil compositions, properties, types according to genetic classification and taxonomic classification, and the north boundary of subtropical zone on the southern slope of Funiu Mountain were discussed in this paper based on soil survey in field and soil physical and chemical analysis in laboratory. There were some vertical varying laws of soil compositions and properties on the southern slope of Funiu Mountain. (1) The content of fulvic acid in soil humus exceeds that of humic acid in all profiles of soil (HA/FA<1). The ratios of HA/FA in surface horizons are rising from foot to top of the mountain. The degree of humification in soil humic acid at 900 m asl is the lowest. (2) Along the altitude from foot to top of the mountain, both soil pH and base saturation percentage go down first, then go up. (3) Soils below 900 m asl have remarkable clayification horizon, argic horizon appears in each soil profile, and soils above 900 m asl have no clayification and argic horizons. (4) All of soils have higher degree of weathering and ferrallitization, average migration coefficients (Kmx) of most oxides and the values of β in all of soil bodies are below 1, the values of "Saf" are smaller than 5.06, the contents of Fed in illuvial horizons are higher than 20 g·kg-1, the percentage of Fed/Fet in illuvial horizons is higher than 40%, and many kinds of ferromanganese (concretion and coating) appear in all soil bodies below 900 m asl. But for soils with lower degree of weathering, no ferrallitization takes place, and no ferromanganese appears in all soil bodies above 900 m asl. The north boundary of subtropical zone on south slope of Funiu Mountain is in the area between S3 and S4, ranging from 900 m to 1000 m, the average height of which is at 950 m above sea level.
The distribution of soil organic matter (SOM) and nitrogen of Gongga Mountain were studied in this paper. The results showed that the contents of SOM and N of A horizon had an ascending trend with the increase of the elevation. The vegetation types distributed higher than the mixed broad-leaved conifer forest had the irregular trends. In the transitional communities such as mixed forest and treeline, the contents of SOM and N were higher than other vegetation types. The distribution of SOM and N of A horizon was determined by the mutual effect of climate and vegetation types. The vertical distribution of SOM and N in soil profile had the similar trends in all kinds of vegetation types, i.e., the content of A horizon was higher than that of the B and C horizons, which was the same to the distribution of dead animals and plants in soil. There were N accumulation peaks in A horizon of the transitional communities. The soil C:N is between 7 and 25, which is lower relative to the appropriate C:N of 25-30. The soil C:N increased with the increase of the elevation, but its vertical distribution in the soil profile varied with different vegetation types. The N in the SOM existed mainly in the form of organic nitrogen, and the soil C:N was significantly correlated with SOM.
In this paper, two mathematic models are used to measure the spatial structure and the competition pattern of the coastal container port system of China from 1992 to 2001. Shift-share analyses reveal some characteristics for the competition pattern of the coastal container port system of China: (1) Both between (inter) and within (intra) the different port ranges, the net volumes of the shift effects are very notable. (2) In competition, the Pearl River Delta container port ranges are all along superiorior; the around the Bohai Sea container port range is throughout inferior; the Changjiang River Delta container port range is relatively complicated. (3) From 1995 to 1998, Shanghai was one of the major winners interms of total shift, but in the other two periods, it lost some TEU. (4) Shenzhen and Ningbo ports have been the major winners interms of total shift since 1992.
This paper reviews the research development process of Chinese commercial geography, and the study process of business geography is divided into 5 stages, that is the initiate stage, formation stage, depressed stage, ferment stage and living stage. It examines the 5 directions of research on business geography since the ferment period of 1984, such as business area and district structure, theory and method on business circle, research on central business district (CBD), retail industry theory and net distribution, consumer behavior and the effect on commercial location. Finally it discusses the characteristics of business geographic development and existing problems, and prospects 4 hot spot issues points about for future research in commercial geography such as research on urban commercial area and structure, research on business suburbanization and dispersing, commercial form and management problem, commercial geographic development in commercial business planning and so on.
CLUE-s (Conversion of Land Use and its Effects in small extent) is a model for simulating spatial changes in land use. The model was applied for regional agriculture and forest land-use system simulations in many countries. The author extended the CLUE-s model with a dynamic neighborhood analysis. The extended model (CLUE-sII) could simulate the self-organizational processes, spontaneous processes and the competition processes of the land-use changes. CLUE-sII can also implement different simulation schemes according to the characteristics of the study area. The local factors and the neighborhood factors play different roles in each scheme. Therefore, the researchers could find the best scheme for the specific study area. Land use change from 1991 to 2001 is simulated using CLUE-sII for Haidian District, Beijing. The results indicate that neighborhood factor analyse is important to simulate urban land-use changes and the scheme that took the neighborhood factor as a magnifying factor to the spontaneous processes obtained the best results, with which the whole map correspondence proportion gained 77% and the Kappa of urban attained 0.754. The case study in this paper showed that CLUE-sII could simulate urban sprawl with multiple land-use types at a high spatial and temporal resolution. Through constructing multiple simulation schemes, one can not only find the best simulation performance, but also could obtain more information on the importance of different land-use drivers.
Based on analysis with ESDA-GIS framework, by using statistical data of 1346 small cities and towns in Jiangsu province in 2002, their spatial structure was studied. We, at first, finished summary factor analysis from database, and drew the two principal components: economic factor and scale factor. By comparison, we found that the frequency distribution of the two factors was skewed and the skewed degree of scale factor was higher than that of economic factor. But there is no positive correlation as scale-benefit between the two factors. In this paper, exploratory spatial structure of the small cities and towns was analyzed. With the density map, we found their spatial distribution is imbalanced, whose density would descend gradually from Yangtze River zone and Taihu Lake area in the southeast to the west and the north, which showed a belt and circle structure. Based on the analysis with global SAMs and local SAMs, we came to some conclusions. The spatial distribution of economic factor of the small cities and towns showed positive autocorrelation and spatial cluster, but the autocorrelation of scale factor is very weak. Finally, after classifying the local SAMs coefficients of small cities and towns according to administrative units of country, we analyzed economic significance with anisotroptric variogram and improved the classified result. We found the spatial cluster of the economic development of the small cities and towns in Jiangsu province: three districts, one belt, and one part, i.e., the middle part of the northern Jiangsu area, the middle part of Jiangsu province and Nanjing-Zhenjiang area, Suzhou-Wuxi-Changzhou area, and the northern part of Jiangsu border belt, and district around Suining. The corresponding economic development types are diffusing development type, polarizing development type, clustering development type, transitional development type, and continual impoverished type.
Based on SPOT remote sensing images and GIS, choosing the central area of the external circle highway in Shanghai as a case study area, the paper studied the spatial scaling effect of the urban landscape pattern with different grains and extents. The conclusions are drawn as follows: (1) The spatial autocorrelation of urban landscape pattern depends on different scales within a certain range of scales, and Moran I and Geary c related to the grains, which characterized the spatial autocorrelation of the urban landscape structure, have the same sensitive points to the scaling at the level of 50 m. (2) The patches of all kinds of landscapes have the fractal character. The fractal dimensions of landscapes respond to scaling differently, and the present nonlinear change trends with grains. The fractal dimensions of landscapes are obviously different at a small grain, but the differences become not obvious with the increasing grain. (3) The landscape diversity are closely linked to the location and the pattern of human activities, especially to economic and social activities. Due to the high land cost in the urban center, the dominant landscapes are mainly for business and culture, and their patches have the characters of high congregation and high fragmentation. While agricultural landscapes with low economic benefit can only be located at the fringe or outskirt of the urban area, and they have the characters of simplex, larger patches and less fragmentation. (4) The landscape diversity depends on spatial scale. With the increasing extent, the Shannon diversity index (SHDI) increases and the spatial pattern of landscape varies dramatically. At 0.5 km extent, the maximum of diversity is in the center of the urban area. The landscape diversity is distributed with a ring mode up and down from the center to the outer. With the increasing extent, the maximum of diversity moves to the urban-rural transition zone where landscape types change dramatically. (5) The semivariogram discloses the spatial variance character and internal mechanism of landscape diversity. At a small scale, the spatial variance of diversity is more complicated. The spatial heterogeneity, which is caused by spatial autocorrelation, contributes a lot to the total spatial heterogeneity of terrestrial ecosystem, while the spatial heterogeneity caused by random factors (scale and measure error) contributes less. The increasing scale washes off the detailed variances in a fine scale. The coarse scale may result in more nugget effect and less contribution, which is caused by spatial autocorrelation.
The rapid development of urbanization in China started in 1996 with two basic characteristics: the economic globalization and the transformation of economy. In the author's opinion, accumulation and diffusion are the two fundamental dynamic forms of the flow and the essential manifestation of the dynamics of urbanization. The author, by establishing an urbanization policy model of rural surplus labor force under indefinite situations, tries to explain the differences of the speed of urbanization between the period after the adoption of reform and open-up policy and the period of rapid development of urbanization, and comes to the conclusion that the latter period is the natural result of the combined force of the government and the market. Moreover, by making a metrological analysis on the numerical relationship between traditional industrialization and urbanization, the author promotes the opinion that the rapid development of urbanization is mainly stimulated by the tertiary industry. Then the author roughly estimates the industrial output value according to the import and export margin of industrial products and calculates the contribution of international trade to the development of urbanization.
Regional growth is one of the key problems of the regional economic study. As the shortage of resources had not been fully realized, the binding force and the carrying capacity of environment and resource to labor (population) and regional economy were not taken into consideration in the classical theory of regional growth. Based on the modern economic growth model and Logistic population growth model, a dynamical model of regional growth bounded by the regional resource and investment environment is set up in this paper. By the regional growth dynamical model, taking the economic development in Jiangxi province since 1978 as an example, the simulation study on the key economic growth factors is conducted. The simulations show that: (1) The key factor influencing the labor scale of the developing city (region) is the carrying capacity of resources and the actual increase rate of labor. The former determines the labor scale of the developing city (region), while the latter restricts the speed of regional growth. Furthermore, the influences that the carrying capacity of resources acts to the scale of regional labor and the actual labor growth rate acts to the regional growth speed are linear. (2) We should improve the investment environment of the developing city (region) and make it much better than that of the neighborhood city (region) so as to develop its economic scale further. Whereas, if its investment environment is worse than that of the neighborhood city (region), its economic scale will be limited to some degree and cannot be enlarged. (3) Among all the economic factors, the magnitude of the effects on regional growth is in the turn of the difference of the internal and external investment environment, the difference of the average wage inside and outside the region, and the saving rate. Thus, improving the investment environment and increasing the average wage inside the region are the two most important internal powers to assure the city development steadily and constantly.
