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  • 2001 Volume 56 Issue 3
    Published: 15 May 2001
      
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  • Spatio-temporal Change of Land Use in Bohai Rim
    ZHU Hui yi, LI Xiu bin, HE Shu jin, ZHANG Ming
    2001, 56(3): 253-260. https://doi.org/10.11821/xb200103001
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    Regional land use change is an important part of global change The Bohai Rim is one of the hot spots for socio economic development in China, so the land use change will be improved greatly Based on the RS and GIS methods, we analyze the land use information from 1985 and 1995 TM images, then in both spatial and temporal aspects, we analyze the situation of land use change in the region It is found: (1) The land use changed greatly in the Bohai Rim during 1985～1995 The cultivated land decreased by 1 800 000 hm 2, forestland increased by 600 389 hm 2 and land for housing and other construction purposes increased remarkably in the last ten years (2) The speed of the land use change in the region was up to 0 85% per year The cultivated land decreased at the rate of 1 26% per year, land for housing and other construction purposes, water area, and forestland increased at different rates, among which land for housing and other construction purposes and water area were the highest (up to 6 40% and 6 95% per year respectively) (3) There were notable differences of land use change among the sub areas in the region For cultivated land change, Beijing and Liaoning Province (partly) was the greatest, Hebei Province the smallest For land for housing and other construction purposes, Liaoning (partly) was the greatest, Beijing the second, Tianjin the smallest in land use change (4) As to the spatial change, 30% of the area in the region was under the changing process, major types of which were cultivated land turned to be land for housing and other construction purposes, and cultivated land turned to be forestland and grassland Those types of land were distributed widely and differently in different areas, but mostly near the mountains and in areas joining the town and country (5) The direction of land use change in the region was to occupy cultivated land for and convert land between forest and cultivated land at different units into that for housing and other contruction purposes.
  • Regional Evapotranspiration Estimation over Northwest China Using Remote Sensing
    CHEN Yun hao, LI Xiao bing, SHI Pei jun
    2001, 56(3): 261-268. https://doi.org/10.11821/xb200103002
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    It is a very complicated problem to estimate evapotranspiration (ET) over large area of natural land surface In this paper, the evapotranspiration estimation models for dense vegetation and bare soil are presented based on information of surface parameters like vegetation fraction and surface albedo Combined with vegetation fraction data, a model for regional evapotranspiration estimation over the heterogeneous landscape is derived Meanwhile, through a case study with remote sensing data over Northwest China, the accuracy of the model for regional evapotranspiration estimation is checked, which shows a high accurate result The features of evapotranspiration over Northwest China are also discussed with the model.
  • Changes in Sediment Deposition and Erosion and Their Spatial Distribution in the Dongting Lake
    GAO Jun feng, ZHANG Chen, JIANG Jia hu, HUANG Qun
    2001, 56(3): 269-277. https://doi.org/10.11821/xb200103003
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    The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of them are transported into the Yangtze River at Chenglingji, which is located at the exit of the Dongting Lake, some of them deposit into drainage system in the lake region and the rest deposit into the lake The annual mean sediment is 166 555×10 4 t, of which 80% come from the four channels, 18% from the four tributaries and 2% from local area, whereas 26% of the total sediments are transported into the Yangtze River and 74% deposited into the lake and the lake drainage system The sediment budget in the lake can be expressed as follows: V FourMouth +V FourRiver +V Location +V Erosion -V Out =V LakeSediment +V DrainagesystemSediment where V FourMouth is the sediments from the channels which connect the Yangtze River, V FourRiver is the sediments from the tributaries, V Location is the sediments from local area, V Erosion is erosion from the lake, V Out is the sediments carried into the Yangtze River,V LakeSediment is the sediments deposited in the lake, and V DrainageSystemDediment is the sediments deposited in the lake drainage basin Based on topographic maps in 1974, 1988 and 1998, and the spatial analysis method with geographic information system (GIS), the changes in sediment deposition and erosion are studied in this paper By overlay analysis of 1974 and 1988, 1988 and 1998, erosion and sediments deposition areas are defined The main conclusions are: (1) sediment rate in the lake is larger than erosion rate from 1974 to 1998 The mean deposition in the lake is 0 43 m; (2) annual sediment deposition is the same between 1974～1988 and 1988～1998, but the annual volume of deposition and erosion of 1988～1998 is bigger than that in 1974～1988; (3) before the completion of the Three Gorges Reservoir, there will be 7 82×10 8 m 3 sediment deposited in the lake, which would make the lake silted up by 0 33 m; (4) in the lake, the deposition area is found in the north of the east Dongting Lake, the south west of the south Dongting Lake, and the east of the west Dongting Lake; while the erosion area is in the south of the east Dongting Lake, the middle of the south Dongting Lake, the west of the west Dongting Lake.
  • The Spatial Analysis of Erosion and Deposition of Tidal-Flat by GIS
    LI Heng peng, YANG Gui shan
    2001, 56(3): 278-286. https://doi.org/10.11821/xb200103004
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    To study the distribution of erosions and deposition in Fengxian tidal flat, the elevation of tidal flat were measured in 9 years The elevation data in 1999 and 1998 were digitized to get point distribution map The Beijing Projection was used Interpolating elevation and slope analysis to point elevation were finished by using the Grid and Tin (Triangular Irregular Network) modulus of Vertical Mapper1 5 software, which generated the topographic and slope maps of 1999 and 1998 The project and cell length of the two maps identical Length of per grid is 0 05 km In the environment of Vertical Mapper1 5, the 1998’s topographic grid subtracted the 1990’s topographic grid to acquire the grid and contour maps of erosion and disposition between 1990 to 1998 Then overlaying the erosion disposition grid map and slope grid with the point distribution map, profile location map and standard tidal level location map, the erosion disposition amount and slope value of point measured, the data of profile and the shoreline change map were acquired Based on the analyses of the erosion deposition amount, slope value, coastal profile, erosion deposition distribution, shoreline change, the erosion deposition features of Fengxian tidal flat are classified as follows: 1 Three belts from north to south are divided, that is, slight eroding belt of tidal flat, severe eroding belt with steep slope and slight deposited belt between -7 and -9 5 Due to eroding, the elevation of high tide will decrease and even disappear, and the steep slope is approaching toward the shoreline The landward retreat of MLTL is at a rate of 31 m/a The feature of erosion deposition distribution from west to east is that the tidal flat of the east and the central sections are eroded more severely than the west At present, there is no high tidal flat in the east 2 On the tidal flat above MTL(the mean tide level), there are erosion area and deposition area, but are mainly erosion areas The mean erosion velocity of this area is about 2 8 cm/a Most of the tidal flat between MTL and MLTL is erosion area The mean erosion velocity is about 6 5 cm/a The steep bank slope between MLTL and -7 m contour is the most severely eroded area The mean erosion velocity is about 17 9 cm/a The deep bank slope between -7 m and -9 5 m contour is depositional area The mean deposition velocity is about 5 3 cm/a 3 The amount of erosion deposition is related to the slope The regression equation is given below:Y=0 062-0 12X Y is the velocity of erosion deposition The unit is m/a X is the slope of tidal flat The depositional areas are distributed on the high flat and the deep water bank, the slope of which is less than 0 1 The most severe erosion is distributed on the steep bank slope According to the relationship between erosion deposition and slope, we can foresee that the erosion on the slope between MLTL and -7 m contour will be more severe because the slope of this area is increasing 4 The sediments were mainly eroded from tidal flat and the steep slope between MLTL and -7 m contour and deposited on the deep bank slope below -7 m contour The closure depth is about -9 5 m
  • Study on the Relationship Between Different Ecosystems and Climate in China Using NOAA/AVHRR data
    ZHAO Mao sheng FU Cong bin YAN Xiao dong WEN Gang
    2001, 56(3): 287-296. https://doi.org/10.11821/xb200103005
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    Multiyear (12a) NOAA/AVHRR NDVI and meteorological station data were used to study the relationship between different ecosystems and climate in China In order to investigate the responses of different vegetation types to inter annual climate variability, we classified 21 vegetation types using GIS and the principal component analysis (PCA) Monthly NDVI was got for each meteorological station through its longitude and latitude The relations between averaged NDVI and precipitation, and temperature suggest that precipitation plays a more important part for the ecosystem than temperature does in China The relationship between NDVI and climate at an averaged year shows that temperature has a stronger force than precipitation, while precipitation causes different responses of vegetation to climate The correlations of seasonal variations between NDVI and precipitation, and temperature indicate that the responses of ecosystem to inter annual variability of climate differ at seasonal level, and that NDVI data in winter are inappropriate for investigating the variability of ecosystems in northern China To study ecosystem climate relationship at annual level, the data within growing period (April to October) for vegetation in most parts of China were used, and the results show that ecosystem climate relations for different regions differ greatly In southern China, there is a negative correlation between precipitation and NDVI and a positive correlation between temperature and NDVI.
  • Remote Sensing Analysis of Alpine Landscape of Wutai Mts., Shanxi Province
    CAO Yan li, CUI Hai ting LIU Hong yan DAI Jun hu WANG Gao jian
    2001, 56(3): 297-306. https://doi.org/10.11821/xb200103006
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    Based on TM data and GIS technique, the alpine landscape of Wutai Mts was analyzed on different spatial scales by using methods of climate parameters contour map, 3 D analysis of topography, and overlay of climate parameters contour map and landscape map with DEM We interpreted the landscape map from TM image and calculated the landscape indexes We consider that overlay of climate parameters contour map and landscape map with DEM is good to reflect the landscape structure and its mechanism We concluded that Wutai Mts can be regarded as the coldest and wettest center of the surroundings Alpine zone of Wutai Mts lies at an altitude of above 2 890 m Alpine Kobresia meadow is the main element of alpine landscape of Wutai Mts and it is a unique and fragile ecosystem in North China Alpine landscape reserve should be established.
  • Sandy Desertification in West of Northeast China Plain in the Past 10 Years
    LI Bao lin, ZHOU Cheng hu
    2001, 56(3): 307-315. https://doi.org/10.11821/xb200103007
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    Sandy land of the Northeast China Plain lies in the eastern fringe of huge sandy belt of mid latitude in Eurasia. Using RS and GIS, the index of desertification degree is established to detect the dynamic change of desertification based on NOAA/AVHRR data, and the modern modes of desertification are studied based on TM data According to the statistics, the light desertified land decreased from 38 216 3 km 2 in 1990 to 26 452 2 km 2 in 1997, and severe and very severe desertified land increased from 3268 2 km 2 and 3 511 9 km 2 in 1990 to 4 887 3 km 2 and 5 966 4 km 2 in 1997 respectively. The ratio of reversion desertified land, the ratio of development and the ratio of steadiness accounted for 7 7%, 39 9% and 53 4% respectively The modes of desertification include the moving accroachment of the quicksand to the farmland or grassland, sheet like enlargement of quicksand in grassland and farmland, patch like enlargement of quicksands on sand ridges around residential areas, wind erosion in farmland and grassland and sand covering on the ground Sandy lands for combating desertification can be divided into sub regions including where people removing out to abate the pressure of population, adjusting the distribution of residential areas, restricting the overgrazing.
  • Temporal-spatial Distribution as well as Tracks and Source Areas of Sand-Dust Storms in China
    QIU Xin fa, ZENG Yan, MIAO Qi long
    2001, 56(3): 316-322. https://doi.org/10.11821/xb200103008
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    Sand dust storm is a special natural disaster that frequently occurrs in deserts and their surrounding areas. With the data published on Surface Meteorological Monthly Bulletin and Surface Chart during 1971～1996, the temporal spatial distribution and annual variation of sand dust storms are analyzed on the basis of the case study of atmospheric process. Furthermore, the tracks and source areas of sand dust storms are determined assisted with GIS. The results show: Except parts of Qinghai Province, Inner Mongolia and Beijing, the sand dust storms decrease greatly both in time and space in recent decades in China. Sand dust storms occur most frequently in spring, especially in April. According to their source areas, the sand dust storms are classified into two types, i.e. the inner source and outer source sand dust storms. Most of the outer source sand dust storms move along the north and west tracks. For the north track outer source sand dust storms, they always intrude into China across the Sino Mongolian boundary from Hami, a city in the eastern part of Xinjiang, to Xilin Gol, a county in Inner Mongolia, while the west track ones intrude into China both from southern Xinjiang and northern Xinjiang. The source areas of inner source sand dust storms are the Taklimakan Desert and its surrounding areas in southern Xinjiang, southern part of the Junggar Basin in northern Xinjiang, Hexi Corridor in the west of Gansu Province, the dry deserts of Inner Mongolia and the Qaidam Basin in Qinghai.
  • The Paleosol and the Migration of Climatic Zone about 500 ka BP in Loess Plateau, Shaanxi Province
    ZHAO Jing bo
    2001, 56(3): 323-331. https://doi.org/10.11821/xb200103009
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    It is discovered through field investigations that the illuvium of CaCO 3 in the 5th layer of paleosol in Changwu and Xi’an does not get in touch with the bottom of clay grouting layer but lies in loess which is 0 5～2 3 m deep under the bottom of clay grouting layer, and the red ferruginous clay film also migrated to the mother loess It is indicated that CaCO 3 and Fe 2O 3 migrated out of the paleosol, the paleosol has the character of acid elevation and at least the weathering had already been in the middle of the chemical weathering process at that time The weathered loess layer (Cs) with ferruginous film and weathered loess layer (Cl) without ferruginous film were discovered under the bottom of the 5th layer of paleosol in Changwu and Xi’an, and the light red brown weathered loess layer (Cf) with ferruginous concretion was discovered under the bottom of 5th paleosol in Xi’an Generally, the content of CaCO 3 is less than 0 5% in weathered loess layers, and the content of clay grains, Fe 2O 3 and Al 2O 3 is higher in weathered loess layers than in the unweathered loess layer, which indicates that each of the weathered loess layer had experienced chemical weathering to a certain extent The material shows that the 5th layer of paleosol in Changwu and Xi’an has the character of subtropical soil and its profile construction is Bts Cs Cl Bk C in Changwu and is Bts Cf Cs Bk C in Xi’an The content of smalite takes 8% 9% in the clay film of the 5th layer of paleosol in Xi’an, the sporo pollen of some subtropical Liquidambar and Castanoposis appear in the paleosol in Changwu, which points out that the 5th paleosol developed in subtropical climate Six indexes, removed depth of Fe 2O 3 and CaCO 3, deep weathered loess layers and sporo pollen and so on, indicate that the subtropical climate migrated to the middle area of Loess Plateau at about 500 ka BP, mean annual precipitation was 850～900 mm in Changwu area and was about 1 100 mm in Xi’an area According to the obvious increase of the precipitation at about 500 ka BP and 100 ka BP ascertained by the author, after eliminating the effect of the new tectogenesis, it can be drawn that in interglacials which was obviously warmer than today.
  • Grain-Size Cycles in Salawusu River Valley since 150 ka BP
    ZHANG Yu hong, LI Bao sheng, JIN He ling, David Dian Zhang, YAN Man cun, ZHU Yi zhi, LI Hou xin, YAO Chun xia, LUO Kai li
    2001, 56(3): 332-344. https://doi.org/10.11821/xb200103010
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    The Milanggouwan stratigraphical section in the Salawusu River Valley takes down 27 alternately evolutionary sediment sequences of the aeolian dune layers with the fluvio lacustrine facies and palaeosols since 150 ka BP Based on grain size analyses of the 86 samples from the section, some views have been put forward: (1) Grain size accumulative centigrade contents of the aeolian sands in the past 150 ka in Milanggouwan section are mainly characterized by the aeolian palaeo mobile dune sands, and those of the fluvial facies dominated by very fine sands also contain some quantities of silt and clay (2) The grain size general distributional characteristics — Mz (particle diameter) and σ (standard deviation) clearly show that the fluvio lacustrine facies and palaeosols usually become finer in particles and worse in sorting than the aeolian sands As regards Sk (bias angle) and Kg (kurtosis) values, the former two increase obviously compared with the latter, displaying positive bias and the latter often proximately symmetrical distributed, only few in negative bias (3) At vertical direction of the section, the grain size distributional coarse and fine rhythms vary very pronouncedly with the alternation of sedimentary facies Mz, σ, Sk, Kg and SC/D (ratio of the sum of silt and clay to sand) of fluvio lacustrine, palaeosols and aeolian sands separately constitute a commulative between peak and valley values. (4) The values of grain size parameters lie on their eigenvalues Taking the eigenvalue Φ50 as a boundary, the Φ75, Φ84 and Φ95 above the eigenvalue have wide flounce range and high sensitivity responding to the sedimentary facies, which may be called "active eigenvalues". In contrast with them, those below the above cited eigenvalue, i.e., Φ5, Φ16 and Φ25, which have relatively narrow flounce range and low sensitivity.
  • Paleoclimatic and Paleoenvironmental Changes in Southern Xinjiang during Historical Period
    ZHONG Wei, XIONG Hei gang, TASHPOLAT稵iyip, HIROKI Takmura, SHU Qiang
    2001, 56(3): 345-352. https://doi.org/10.11821/xb200103011
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    Based on synthetic researches of multi index geological records of Niya section, which are of high resolution in southern margin of the Tarim Basin, together with other geologic records in southern Xinjiang, this paper has reconstructed the history of paleoclimatic changes in this region since about 4 0 ka BP) During the last 4000 years, the area of southern Xinjiang has experienced alternations of relative cold wet and relative warm dry periods Three evident cold wet periods and three warm dry periods are identified (1)Relative cold wet period (4000 3450 a BP) Multi geologic index and pollen assemblege in the layer of Niya profile shows the characters of aridity (2)Relative warm dry period(3450 2500 a BP) The period corresponds to the Shang, Western Zhou dynasties and Spring and Autumn Period The result of study shows that this period is a relative warm dry period (3)Relative cold wet period(2500 1900 a BP) The phase likely corresponds to the Warring States, Qin and Han dynasties The peaks of the curves of geochemical element ratios, δ 13 C and Xlf, as well as A/C all indicate a relative wet character, and coincides with the research results of other areas in Xinjiang (4)Relative warm dry period in climate(1900 1400 a BP) The phase corresponds to the later part of the Western Han Dynasty and most of the Wei and Jin as well as Northern and Southern Dynasties The changes of the geochemical element ratios,δ 13 C and Xlf all display evident warm dry characters (5)Relative cold wet period in climate(about 1400 1000 a BP) The period includes Sui and Tang dynasties (581 907AD) and early Song Dynasty Although several slight cold wet and warm dry fluctuations appeared, it was mainly cold wet in climate, the paleoclimate began to be desiccated in the later period (6)Relative warm dry period in climate(1000 a BP present).
  • Environmental Archaeological Exploration in Zhangjiawan Site, Chongqing since 2 ka BP
    ZHANG Qiang, ZHU Cheng, JIANG Feng qing, GUO Li xin, LIU Xin lin
    2001, 56(3): 353-362. https://doi.org/10.11821/xb200103012
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    Analytical results of grain size and magnetic susceptibility performed on samples from the west wall of the T911 at Zhangjiawan site show that climate evolution, to a certain degree, is under influence of the changes of the southwest mosoon Development of the agriculture and handicraft industry made an excessive exploitation of the vegetation resources and the ill consequences of the human activities made the ecological environment in the study area deteriorate and finally made the civilization collapse Archaeological excavation shows that the study area was a developed economic center with flourished, handicraft industry and agriculture at that time As a result of the blind exploitation of the natural resources, the ecological environment was deteriorated Without protection of the vegetation, the detrital materials on the sloping land provide conditions for landslides and erosion, leading to decline of local civilization The eco environmental evolution of this area is thus controlled by human activities and also changes of the strength of the south west mosoon Huge mountain ranges surround the study area from north west and south east respectively, and the geomorphologic features make the area unique both climatically and ecologically The mode of the environmental evolution is distinctive from any other regions.
  • Regional Carrying Capacity in Bohai Rim
    MAO Han ying, YU Dan lin
    2001, 56(3): 363-371. https://doi.org/10.11821/xb200103013
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    Bohai Rim, one of the developed and urbanized regions in China, plays an important role in the new century development. Now the load on the regional resource and environment has been over carried which has been one of the main restrictive factors for the future socioeconomic development in this region. After retrospection of the previous research methods on regional carrying capacity at home and abroad, this paper takes the state space as a basic method to measure regional carrying capacity on account of implementing regional sustainable development strategy. It does quantitative evaluation of regional carrying capacity by building an index system. The conclusions are as follows. The carrying status of resource and environment was over loaded from 1994 to 1998 in this region. Seriously inadequate per capita possession of water resource and utilizable water decreasing caused by pollution are main restrictive factors. Furthermore serious shortage of water resource has close relationship with furious speed extensive economic development pattern. In view of the above mentioned conclusions, this paper simulates and forecasts the regional carrying capacity and status by the agency of system dynamics. The general trend is briefed below. The over loaded tendency remains as before, but the carrying status of each time is evolving toward better. It is forecasted that the carrying status will approach the carrying capacity in the year 2015 which shows this region will develop from weaker to stronger sustainable direction. According to this forecast, the authors raise four countermeasures as follows: (1) economic countermeasure: seeking continuous, moderate and coordinated economic growth and adjusting the industrial structure and location; (2) resource countermeasure: adopting the principle of increasing income and decreasing expenditure for shortage resources and building the regulation of utilizing resource upon consideration; (3) environmental countermeasure: strictly executing the total emission control of pollutant, adopting the resource consumption into national economic accounting system progressively and increasing the input to improve eco environmental quality; and (4) population countermeasure: strictly controlling the quantity and improving the quality.