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  • 2005 Volume 25 Issue 4
    Published: 20 July 2005
      

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  • FAN Jie, WANG Hai
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    The level of Tibetan economy and society has been improved remarkably since the reform and opening-up of China. But the population pressure of Tibet has increased as the same time. High natural growth rates in rural areas produces certain negative effects on urbanization and floating population become the main strength for speeding up the process of urbanization in the new era. At the base of talking about the effect of population growth and floating on urbanization, this article analysed the integrative characteristics of the change in urban structure of function, scale and space. It also pointed out that economic function became important factor to accelerate the expansion of urban scales in recent years and the new towns played an important role in Tibetan urbanization which made the spatial pattern of urban distribution become dispersion on the whole and local concentration. Furthermore, conflicts is discussed between population increase, urbanization, resources and environment, and social economy. Authors brought forward some standpoints: first,the convergence of population and industry makes the urban capacity towards gradual saturation; second,the competition for employment and restricted urban capacity brings great pressure on native farmers' urbanization; third, being held up of a great number of farmers in the land aggravated pressures on resources and environment; fourth, the shortage of construction funds influenced the improvement of urbanization quality, and urbanization process brings certain impacts on the protection and succession of Tibetan characteristic culture. At last, there is a brief conclusion that the sustainable urbanization is the goal which can be pulled off in the process of population development and urbanization in Tibet.
  • MENG Bin, WANG Jin-Feng, ZHANG Wen-Zhong, LIU Xu-Hua
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    Based on the social-economic data from 1952 to 2000 in China, the question of regional disparity in China was reconsidered by using spatial analysis methods. Spatial analysis needed in social and economic science for the observed spatial values are not independent each other, i.e., (or) they don't follow the same distribution, and (or) there is a trend along different directions. In this paper, the centrographic statistic was used to estimate basic parameters about the spatial distribution. The geometric center of Chinese Mainland with the centers of arable land area, population and GDP based on provincial level data were compared. The results show that the center of population and GDP had a significant offset with the center of geometry and land use. These are the key to understand the spatial disparity in China. The centers of population have an obviously trend of shift from the east to the west of China Mainland. This may be caused by the family planning and the other polices. But the shifts of the population center will help to improve the development of the west of China. As comparison with population, the shifts of the center of GDP had a different direction. It moved to south since the 1978 while the opening-up policy was adopt in china. In other words, the south of China had more rapid increase than north since 1978. This is not consistent with the opinion that the disparity of regional economic is great from east to west in China. The different shifts of centers of population and GDP also indicates that the economy of west did not increase with the increasing of population. The shifts of population and GDP centers indicate the change of the social and economic pattern in China. The difference of them also indicates that the imbalance of development in China. The Exploratory Spatial Data Analysis (ESDA), which based on the computing spatial autocorelation and spatial heterogeneity, was also used to detect the geographical dynamics of Chinese regional disparity patterns. There are significant positive spatial autocorrelation (Moran's I)of per capita GDP in China. That is, the relatively high (low) developed province tends to be located nearby other high (low) developed provinces more often than expected due to random chance, and then each province should not be viewed as an independent observation. The econometric estimations based on geographical data (i.e. localized data) have to take into account the fact that economic phenomena do not be randomly spatially distributed. We also compared the temporal change of the spatial autocorrelation in China, and found that there is an obviously temporal increase of Moran's I since 1952 to 1995. This means that the disparity is increased in the same periods. But this trend does not keep on since 1990s because we found that the Moran's I soothed with a little fluctuating. Moran's I Scatterplots and LISA (Local Indicators of Spatial Association, LISA) cluster maps were used to test the local pattern of the Chinese economic development. The results of local statistic show that the two types of clusters (High-High and Low-Low) are increasing which means that the heterogeneous is increasing too. And this is the other indicator of the regional disparity in China.
  • LU Feng, XU Jian-Hua
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    The objective of this paper is to apply an inequality composition method, the two-stage nested Theil decomposition method, which is an extension of the ordinary one-stage Theil decomposition method, to an empirical examination of the Chinese regional disparities. One of the innovation of this paper, compared to those previous studies on the same topic, is its multi-scale approach. First of all, the regional inequalities is measured quantitatively in China from 1978 to 2001 by Theil indices based on province-level mean income. Secondly, based on a hierarchical structure of three-level measurement, region-province-prefecture, the paper decomposes overall regional inequality into three components: between-region, between-province, and within-province inequality components. The method uses a prefecture as the underlying regional unit to measure quantitatively overall regional income inequality, rather than a province that is chosen often by the most researchers, and thus can analyze the contribution of within-province inequalities as well as between-province and between-region inequalities to the overall regional income inequalities in a coherent framework. Thus, this paper applies the two-stage nested Theil decomposition method to prefecture-level income and population data in China in 1995,1997,1999 and 2001, and explores the spatial structure of within-provinces inequalities. In the end, to further analyze the results, the three inequality components in 2001 are analyzed in depth separately.Some interesting findings revealed in this study worth further discussion. The most important contribution of recent Chinese regional disparities has been identified with the Theil sub-index of intra-provincial inequalities, which is far more significant than the inter-province and inter-region inequalities components, thus has been recognized as the first and foremost important contributor of recent Chinese regional disparities.
  • LIU Yao-Bin, SONG Xue-Feng
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    Based on Dissipation Structure Theory and the rule of urbanization and ecological environment interaction, the five coupling models which are coordination, basic coordination, threshold, conflict and degradation types have been deduced. According to the models and its evolvement orders, the development paths and trends of the coupling system can been analyzed and forecasted. The threshold is so subtle that we must pay more attention to, or else, the shift from basic coordination to conflict type is dangerous, and the degradation type is so hazardous that we must control and obviate. Through associated analysis and geometrical process, the judgment system to distinguish coordination development has been also put forward on the basis of the coupling models, which is a criterion of evaluating urbanization and eco-environment coordination. If the urbanization comprehensive index and eco-environment comprehensive index are respectively defined as X(t) and Y(t), and differences and the rate of variation defined as ΔX(t), ΔY(t) and ε, the coupling model can be explained on the on a plane. The classifications can be summed up as follows: (1) if ΔX(t)>0, ΔY(t)>0, the coupling system is coordinative; (2) if ΔX(t)=0, ΔY(t)=0 or ΔX(t)>0,ΔY(t)<0, |ΔY(t)/ Y(t-Δt)| =ε, or ΔX(t)<0,ΔY(t)>0, |ΔX(t)/X(t-Δt)| =ε, the coupling system is situated a critical point or a shift threshold; (3) if ΔX(t)>0, ΔY(t)<0, |ΔY(t)/ Y(t-Δt)|<0 or ΔX(t)<0, ΔY(t)>0, |ΔX(t)/X(t-Δt)|<ε, the coupling system is basically coordinative; (4) if ΔX(t)>0, ΔY(t)<0, |ΔY(t)/ Y(t-Δt)| >0 or ΔX(t)<0, ΔY(t)>0, |ΔX(t)/X(t-Δt)| >0,the coupling system is conflictive; (5) if ΔX(t)<0, ΔY(t)<0, the coupling system is degraded. At last as a case, in terms of the models and judgment criterions, Xuzhou city evolved paths and coupling models have been researched by weighted PCA (Principle Component Analysis) from 1992-2002 in order to develop some suggestion. The studies we have performed show that: there are significantly different development paths of urbanization and eco-environment. In Xuzhou, urbanization comprehensive level has continually been advanced but the eco-environment comprehensive quality curve can be regarded as an inverse "U" figure. At the sametime there are four coupling types involved in Xuzhou City, and the coordination & basic coordination types are main ones. With the case studies, it proved the evaluation method and the judgment system which was simple and effective to appraise and coordinated regional urbanization development with eco-environment protection.
  • KANG Shi-Chang, QIN Da-He, REN Jia-Wen, ZHANG Dong-Qi, QIN Xiang
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    Researches in transformation of snow to ice are significant for choosing ice coring site. Due to lacking of observed data at higher elevation, earlier studies on the transformation of snow to ice were very limited in the East Rongbuk Glacier, northern slope of Mount Qomolangma. During September, 1998, the ice coring project has been carried out on the northern slope of Mount Qomolangma. The analysis of an 11 m ice core at the col (6500 m a. s. l.) and a 20 m ice core at an elevation of 6 450 m in the East Rongbuk Glacier indicates that transformation of snow to ice is varying annually, which may depend on variation of air temperature and precipitation amount. In the high elevation region of the East Rongbuk Glacier, the refrozen-recrystallization is dominant in transforming of snow to ice at the certain conditions, such as low summer temperature or high precipitation. In another word, the refrozen-recrystallization zone does exist in the East Rongbuk Glacier (at least at the col of the glacier). The cold percolation-recrystallization is major transforming process from snow to ice when summer temperature is high or precipitation is low. The result clarifies the uncertainties of transformation of snow to ice in the high elevation over the Himalayas. It also encourages us to recover ice cores that have reliable records from the accumulation area of glacier at the high elevation of the Himalayas.
  • YOU Wei-Hong, HE Da-Ming, GUO Zhi-Rong
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    In order to investigate the basic facts that the climate changes influence the hydrological and water ecological environment variations of the Lancang-Mekong River Basin, this paper studies on the correlation characteristics between the Lancang River flow change and the precipitation field change over Yunnan based on the observational data of the Lancang River flow and precipitation field in Yunnan and using the correlation analysis method. The results show that there is a very significant correlation between the transboundary flow variations for the Lancang River and the precipitation field variations over Yunnan. The main reasons for the transboundary flow variations of the Lancang River are the variations of the precipitation field over Yunnan. In general, the precipitation field variations over Yunnan significantly influence the transboundary flow variations for the Lancang River in four seasons, and the best season is in Spring of March-May, the secondary seasons are Summer of June-August and Autumn of September-November, but the relatively poor season is Winter of December-February.
  • HU Jin-Ming, DENG Wei, XIA Bai-Cheng
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    LASCAM (Large Scale Catchment Model) is a kind of large-scale catchment hydrological model with intermediate resolution between the fully lumped conceptual hydrological model and the fully physically-based distributed hydrological model. LASCAM first develops the lumped conceptual model at all subcatchments which form the building blocks for the hydrological modeling of the whole catchment. Each subcatchment includes 3 conceptual soil water stores: A representing the near-stream perched aquifer, B representing the permanent deeper groundwater store, and F representing the intermediate unsaturated infiltration store. Water balance and water flux processes of and within each soil water store are the most important for model construction.Lumped conceptual model at subcatchment scale is the building block to the catchment model. Water levels of each soil water store will control the main water fluxes and other hydrological processes within the subcatchment. Based on empirical equations resulted from regional case studies in southwest area of the Western Australia, at the scale of each subcatchment, LASCAM: 1) first establishes the functional relationship between each soil water store and ecological (Leaf Area Index) and climatic characteristics (precipitation); 2) constructs a series functions to model precipitation interception through canopy, surface runoff generation processes, processes of surface infiltration and subsurface runoff generation, subsurface infiltration to F store, which unveil the reallocation processes of ground precipitation to runoff (including surface and subsurface) and infiltration within each subcatchment; 3) builds water flux processes between each soil water store based on their water quantity (water level); 4) builds the links between the evaporation of each soil water store and ecological characteristics (LAI) to model evaporation of each store. In the end, LASCAM integrates runoff generated in each subcatchment into the whole catchment through stream network routing subroutine and the distribution status of each subcatchment within the whole catchment, which makes it possible to model the hydrological processes and water balance of large-scale heterogeneous catchment.
  • ZHANG Dong, ZHANG Wan-Chang, ZHU Li, ZHU Qiu-An
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    SWAT (Soil and Water Assessment Tool) model is an advanced, physically based, distributed hydrological model that is integrated with Remote Sensing (RS), Geographic Information System (GIS) and Digital Elevation Model (DEM) techniques. In order to impel its application study in China and improve the simulation precision of the model in hydrological process studies, some expansions and improvements were made to the modeling system for the real conditions on arid, semi-arid Heihe River Basin in the northwestern China and humid Hanjiang River Basin in middle-western China. Firstly, soil grain size transferring module and data pre-processing module for weather generator (WGEN) were added to original SWAT model to encounter the inconsistent problems existed in data standard utilized in Euramerican and Chinese systems. And then the further improvements to the model were done focusing on: 1) three new spatial interpolation methods, including Inverse Distance Weighing method (IDW), Thiessen polygonal method and DEM-based PRISM method, were used as a new choice to replace the original interpolation method that takes the meteorological data from the nearest weather station as the representative weather data for each sub-basin. 2) An advanced approach was proposed to modify the original method in daily maximum and minimum temperature estimations in SWAT for avoiding the logical mistakes in temperature simulations. 3) An areal evapotranspiration estimation module based on improved Penman-Monteith method was developed to replace the original approaches used in SWAT. At last the offline experiment on rainfall-runoff simulations were conducted using the meteorological, land use/cover and soil data from the Jiangkou Basin, the Hanjiang River by means of the improved SWAT model and its original version. The detailed study suggested a significant improvement of modeling performance by the fact that in model calibration period, the Nash-Sutcliffe Criterion (NSC) and correlation coefficient were improved from 0.47 and 0.79 to 0.92 and 0.98 respectively, while in validation period, they were improved from 0.08 and 0.68 to 0.94 and 0.97 accordingly. The improved SWAT model and its software packs will impel the application studies in the relevant disciplines in China.
  • YANG Jian-Ping, DING Yong-Jian, CHEN Ren-Sheng, LIU Jun-Feng
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    Herein, we use aridity index, isohyet, and correlation analysis methods to decide the locations and ranges of semi-arid zone, agriculture and pasture interlaced zone, East Asian summer monsoon, and Indian summer monsoon, respectively. Daily precipitation and 20 evaporation pans data were collected between 1958 and 2000 at 553(on the whole China) and 295(in northern China) meteorological stations operated by the Chinese Meteorological Administration. We also use East Asian summer monsoon intensity index data in the period of 1951 to 1995 and Indian summer monsoon intensity index data during 1951 to 1998. The semi-arid zone and ecotone between agriculture and animal husbandry lie along the border of the monsoon, and are thus zones that are highly susceptible zone to environmental change in China, with a direction from northeast to southwest in the middle part of China. We analyze the position variations in the dry and wet climate boundaries and agro-pasturing climate boundaries, and the relations between them and Asian monsoon at 101 year time scale. Study results show that the shifts boundary of agriculture and animal husbandry interlaced zone are weaker than those of the dry and wet climate boundaries. The semi-arid climate zone and ecotone between agriculture and animal husbandry in China are the interlaced regions in East Asia monsoon, India monsoon and other circulations. The different types of circulation and the strength of these circulations result in the regional and temporal differences in their spatial locations. When East Asian summer monsoon strengthens, southeastern boundaries in semiarid zone and ecotone between agriculture and animal husbandry shift northwestward. When Indian summer monsoon is strong, southeastern boundaries in both these zones transfer southeastward. When East Asian summer monsoon and Indian summer monsoon are all strong, arid/semiarid and semiarid/humid boundaries shift northwestward. Diagrammatic presentation in natural factors and analysis in human factors show that spatial shifts in positions in boundaries of agriculture and animal husbandry interlaced zone are mainly a human-induced process, which reflects largely the strengths in human production activity in the present period.
  • GUO Zhi-Mei, MIAO Qi-Long, LI Xiong
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    This paper mainly analyzed the variation characteristics of the mean temperature, the daily minimum temperature and the daily maximum temperature with the time over northern China, including Northeast China, North China and Northwest China, in 1951-2000. The results indicate: The increasing trends of the mean temperature, the daily minimum temperature and the daily maximum are much more significant over northern China in recent 50 years, in the background of global climate warming. The increasing intensity of temperature in Northeast China is more than that in North China and in Northwest China, the increasing speed of the daily minimum temperature is more faster than that of the mean temperature and the daily maximum temperature, as well as the increasing trends of temperature are more obvious in winter than in summer; in addition, there are significant abrupt changes in the mean temperature, the daily minimum temperature and the daily maximum temperature in the mid and late of 1980's; the temperature has been apparently on the high side since the 1990's. However, it is not absolute same to the multi-year change characteristic of temperature in the different seasons and regions, they have themselves special features.
  • HAN Zhi-Wen, WANG Tao, DONG Zhi-Bao, WU Qi-Jun, YAO Zheng-Yi
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    The Taklimakan Desert highway cuts across the simple barchan and barchan dune chain zone,complex transverse dune ridges zone and complex longitudinal megadune zone. Based on a natural year observation data of three meteorological stations (Xiaotang, Mancan and Tazhong) along the Taklimakan Desert highway, we analyzed the blown sand activities that were characterized by intensity of sand driving wind and intensity of sand transport. We select all the winds with velocity greater than the threshold velocity at the standard height of meteorological station as the study winds. We count the frequencies and directions of different level winds by 16 directions and calculate the sand transport according to Bagnold formula of Q=5.2?10-4(V-Vt)3. The study results show that blown sand disaster causing winds come from the north-east (NNE,NE,ENE,E) and their frequencies ranging from 48% to 76%. On time distribution, the blown sand activities were concentrated in spring and summer, especially during the period of April to August. On the spatial distribution, the intensity of blown sand activities were trending stronger from the edge to center of the Taklimakan Desert. The sand transport can reach 6309.5 kg/(m·a) and resultant drift direction is 230?-234癮t the center of the Taklimakan Desert. So we draw a conclusion that the defending measures must be enhanced in the interior desert.
  • XUE Ji-Bin, ZHONG Wei, ZHAO Yin-Juan, PENG Xiao-Ying
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    Based on the historical records of the drought disasters and the waterlog disasters during the 15th-19th centuries, the dry-wet regional differentiation changes of Guangdong Province during the historical periods are discussed in this paper, and the dry-wet distribution features of the studied area in the different stages of the LIA are also discussed. From the analyses of the dry-wet index data of the studied area, we can draw some conclusions as follows:(1)The 113癊 longitude line seems to be regarded as an important characteristic boundary of Guangdong Province, and there are different characteristics of the dry-wet regional differentiation patterns in the east and the west area of the boundary.(2)There were some more and bigger changes of the dry-wet regional differentiation patterns of different stages in the west and the north of Guangdong Province, and there were also some changes in the east of the Guangdong Province. (3)By and large, there were some common characters and still some differences in the dry-wet regional differentiation patterns of different cold and warm stages. According to these analysis results, the conceivable reasons are also discussed in this paper.
  • ZHANG Ting, TANG Guo-An, WANG Chun, LONG Yi, WU Liang-Chao, WANG Zheng
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    Terrain factors, although different in the definition and calculation method, relate each other at different extent. Such relationship can be represented by a correlation index, which reveals the process and stage of terrain development as well. This paper focuses mainly on the correlation between different terrain factors and the mean-slope by means of the Back Propagation model of Neural Network with a latent layer. Furthermore, the regression model and the NN model without a latent layer are compared with the NN model with a latent layer. Fifteen loess gully-hill areas are selected as the experimental area, and the relevant 1:10 000 scale DEMs (5 m?5 m grid) are applied as the basic data. From the results of the NN model with a latent layer, it is found that roughness and undulation are the most closely correlated with mean-slope. Compared with others, channel density and mean elevation are the least correlated with mean-slope. Experiment results show the NN model with a latent layer is better than the others and it can effectively evaluate the correlation between the terrain factors extracted from DEMs. This method provides a new methodology in the selection of suitable and available terrain factors and the estimation of the relevancy between these factors.
  • HU Kai-Heng, LI Yong, WEI Fang-Qiang
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    Drainages can show more complex structure at the smaller scale, which is the representation of the corresponding basin's self-similarity. The detailed structures for different debris flow basins reflect their ability to transport material, which suggests that the small-scale structure plays an important role in the debris flow formation. Therefore, the paper focuses on the drainage hierarchical characteristic of debris flow basin, and two basin parameters (first-order stream number and area threshold) are used to examine this characteristic because the two are not affected by stream ordering methods and DEM errors. Three typical debris flow basins with different catchment area (Jiangjia, Longdong and Guxiang Ravine) were studied, which respectively located in three distinct regions. Using hydrological analysis tool in ArcInfo software the stream networks with different catchment area thresholds were extracted from these basins' DEM and one set of first-order subbasin was identified. It is obvious that these subbasins occupy the whole basin's fringe region where mass transportation starts. So this suggests that the subbasins play an important role in the initiation and material supply of debris flows. Another point is that the number of extracted first-order stream decreases rapidly with the area threshold increasing. It is found that the two parameters have close relation N=RA(a/m) have close relation, and exponent a equals to-1 and coefficient k only relates to the total basin area, namely for the same basin the product of first-order number with area threshold is constant in a wide scale range. The relationship may show that the ability of debris flow basin to transport material doesn't change in so wide scale range. Further research will be paid more attention to the distinction of exponent a and coefficient k between debris-flow basin and non-debris-flow basin.
  • Mao Long-Jiang, Huang Chun-Chang, Pang Jiang-Li
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    Magnetic susceptibility, Total Fe, total organic carbon(TOC), CaCO3 and Rb, Sr, Rb/Sr measurement in the Holocene in this region, have revealed the characteristics of the environmental change of pedogenensis during late 11 500 years, and human activities of the Predynastic Zhou had some influence on the pedogenensis. The results show that dust deposition was reduced because of the climate warming, and the biological weathering is beginning in the early stage of the Holocene. Between 8500-3100 a B.P., pedogenic process was very strong. A layer of Heilu soil was formed on this region. From 3100 a B.P., soil degradation is remarkable. A layer of Loess has been accumulated since 3100 a B.P., which has the Heilu soil buried. This means that the last 3100 years is the dry period with intensified dust accumulation and soil degradation. The cultivating layer of the Predynastic Zhou (180-150cm) was corresponding with the late Holocene Climate Optimum (3350-3100 a B.P.). Monsoon transformation has led to climate aridity and soil degradation from 3100 a B.P., which was the dynamic force of the southward migration of nomads from the steppe of the northern Loess Plateau and the Mongolia Plateau, and the people of the Predynastic Zhou of arable farming community was forced to move south to the Guanzhong Basin, and established their capital city "Qiyi" on the Zhouyuan loess tableland.
  • DI Bao-Feng, YANG Zhong, AI Nan-Shan, ZHANG Jian-Ping
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    Taking Yuanmou County of Yunnan Province as the case, an evaluation on the degraded ecosystem is carried out in Jinshajiang Xerothermic Valley. Based on seven appraisal factors-vegetation index, average patch dimensionality, density of gullies, slop, water-heat belt, livestock carrying and population density, this thesis carries on a comprehensive quantitative evaluation by creating RS and GIS database. The conclusion indicates that there has been a serious ecological degradation in Yuanmou Xerothermic Valley. Compared with the different vertical distribution, the mountain region around the flatland has the most grievous ecological degradation. On the other hand, the non-irrigated farmland, forestland and grassland degrade more seriously among all types of landscape utilization. On the illustration of degraded ecosystem evaluation, the main reasons of ecosystem degradation and rehabilitation methods of degraded ecosystem have been taken under full consideration in this thesis.
  • WANG Chang-Ke, LU Xian-Guo, CAI Zu-Cong, LUO Yong
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    Wetland, one of the most important ecosystems in the world, plays a significant role in global C and N cycles. Although the majority of studies to date have been centered on wetlands as CH4 sources, wetland soils can however also act as CH4 sinks. It has been recognized that Sanjiang Plain palustrine wetland (45°01'-48°28'N, 130°13'-135°05'E), one of the largest palustrine wetland areas in China, play a significant role in the estimation of CH4 budgets. To find the influence of nitrogen fertilizer on CH4 oxidation in mire soils, the fresh mire soil from Sanjiang Plain was amended with 0, 25 or 50 mg(N)/l NH4HCO3 and incubated at 25℃ over six consecutive periods: first at atmospheric CH4 concentration (about 1.8 μL/L), then at elevated CH4 concentration (about 8000 μL/L) for four times, and finally at concentration of about 1.8μL/L. The addition of NH4HCO3 resulted in reduction in the rate of CH4 oxidation approximately in inverse proportion to the amount of NH4HCO3 added. At ~8000 μL/L, the initial inhibitory effect was gradually released and disappeared during subsequent incubations. Finally, NH4HCO3 addition stimulated the CH4 oxidation. NH4HCO3 addition stimulated the rates of CH4 oxidation by the mire soil at atmospheric CH4 concentration during the final incubation. The initial inhibitory effect of NH4HCO3 addition on CH4 oxidation at both atmospheric CH4 concentration and high CH4 concentration in mire soil is temporary, and the long-term effect of NH4HCO3 addition may be stimulating.
  • XIAO Jie-Ying, GE Jing-Feng, SHEN Yan-Jun, LIANG Yan-Qing
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    Land use/cover change research is one of the most important components of the research of global change, and as a focus has attracted more attention among geographers and natural scientists; most of them are on the status, dynamics, mechanism of land use/cover change, and the environment consequences of these changes. The paper, supported by the Landsat TM digital images and ERMaper, analyzed the changing status and features of urban land use/cover from 1987 to 2001, it shows that there are nine types of land use/cover, urban land, resident, arable land, vegetables, wood land, orchards, grass land, water and sands. In this period, urban, vegetables and water areas are increasing rapidly. the urban land, with the increase rate of 81.47%, is dominant at the rim of the old city, and comes from resident, arable land and so on; vegetables, increased with the rate of 73.46%, mainly come from arable land and woods land; water area is increased most rapidly, with the rate of 591.73%, because of the construction of man-made rivers and parks. And the arable land, woods land and orchards are decreasing sharply with the rates of 50.94%, 74.26%, and 53.54% respectively; the urban expansion changed the arable land into urban and resident, and turns the woods land and orchard into vegetables. The grassland is increased from 0 to 2.66 km2 and the sands area is decreased from 2.42 km2 to 0 in the study area. Changed areas are major on the rim of the city (suburban) and the east and northwest part of study area. The study provides: two classification maps of land use/cover about 1987 and 2001, the conversion maps of major types of land use/cover in the period, the distribution maps of land use/cover conversion between some major types. The feature of the land use/cover change is the fast urban expansion around the old city and in eastern part far from center of the city, the vegetable, water area and grassland are increased, and arable land, woods land, and orchards are decreased. other types of land use/cover is changed by the urban expansion, and it is the people lived in the city that decided the distribution of urban expansion. So from this study, we can promote our understanding of land use/cover change in Shijiazhuang.
  • LIN Lan, ZHAO Qin, ZHAO Shu-Ling, DING Deng-Shan
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    Protective development of tourism regionalization is the applied to regionalization of sustainable utilization of nature environment resources and sustainable development of economy.The paper takes Longmen County as an example.With the support of synthesizing the expert system and the quantitative analysis method,the methodology for protective development of tourism regionalization in county is dealed with,and the programme of protective development of tourism regionalization in Longmen and solutions of the sustainable development are gotten.
  • CHEN Yi-Bin, LIANG Jin-Mei, YU Wan-Yuan
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    During the past 20 years, ecotourism is gradually on the upgrade and turning into the mainstream of the tourism development. The tourism development of mountainous area is different from that of other regions, so it is positively and practically significant to study the development model of ecotourism for exploiting the tourism resources in mountainous area. On the base of the concept and connotation of ecotourism, the paper summarizes the development model of mountainous area. Furthermore, giving an example of the ecotourism of Yinna Mountain in Meizhou of Guangdong Province, authors initially probe into the development ways of ecotourism in mountainous area where is remote, not developed and the relatively low grade of tourism resources.