EN中文

Archive

  • 2011 Volume 31 Issue 8
    Published: 20 August 1997
      
  • Select all
    |
  • Spatial Scale Sensitivity of CA-Markov Model
    ZHAO Guan-wei, CHEN Ying-biao, CHEN Jian-fei, LI Jiang-tao
    2011, 31(8): 897-902. https://doi.org/10.13249/j.cnki.sgs.2011.08.897
    Download PDF ( )   Knowledge map   Save
    Cellular Automata (CA) model is an efficient model to simulate land use/cover change (LUCC) process. However, the majority of geographic cellular automata researches now focus more on transition rules than on spatial scale selection. As a result, the spatial scale decisions of geographic cellular automata are often made arbitrarily. When using CA model in geographic context, nontrivial questions have to be answered about the choice of spatial scale and neighborhood configuration. This article takes Huadu district,Guangzhou City as the study area, to investigate the effect of changing spatial scale and neighborhood configuration on the result prediction accuracy of the CA-Markov model and the morphology of land use change simulation result. The result shows that (1)the spatial scale has great impact on the simulation results of CA-Markov model. Coarse cell size will reduce the result prediction accuracy of the model. There is a threshold of cell size in the model. When the cell size exceeds this threshold, the result prediction accuracy dropped rapidly. (2) Neighborhood configuration also has impact on the simulation results of CA-Markov model. The patch number and patch density of simulation result using 3?3 Von Neumann neighborhood are higher than simulation result using 3?3 and 5?5 Moore neighborhood, but there is little difference of Kappa coefficients of the simulation results.
  • The Changes of Land Use and Landscape Pattern Based on Logistic-CA-Markov Model—A Case Study of Beijing-Tianjin-Hebei Metropolitan Region
    HE Dan, JIN Feng-jun, ZHOU Jing
    2011, 31(8): 903-910. https://doi.org/10.13249/j.cnki.sgs.2011.08.903
    Download PDF ( )   Knowledge map   Save
    Taking the Beijing-Tianjin-Hebei metropolitan region as an example, firstly, the best analysis grid size which is 100m is determined. Secondly, using the methods such as Markov transition matrix and landscape pattern indices and so on, land use change, land type transformation, landscape patterns characteristics and land use impact factors are analyzed in the study area. Then, Logistic-CA-Markov coupled model is applied to the quantitative prediction and spatial simulation on the trend of land use change under three different scenarios. The results showed that, ① On the landscape level, the overall degree of landscape fragmentation in the study area is increasing, which is exacerbated by human activities. On the patch type level, urban areas are continuous expanding, and farmland, grassland and woodland are dominant types in the study area, and the degree of fragmentation of cultivated land and water are significantly increased. ② During 1985 to 2000, the cultivated land is the main source of land transfer, which is mainly converted to the residents and urban land, mining land, water and forest. In addition, residents and urban land and mining land mainly come from the cultivated land, grassland and woodland. ③ The distribution of each land type is related to many factors, moreover, the common one is the distance to the original land use type. ④ According to the scenario 1 of land use changes simulating, the cultivated land, woodland, grassland and unused land reduce in varying degrees from 1985 to 2030; on the contrary, urban and residential land and mining land and water increase significantly, which indicate that significantly speeding up of the urbanization process. The construction land is constantly expanding around the original one, and taking up a lot of farmland and other non-agricultural construction.
  • Key Zone, Key Period and Key Factor Influencing Climate in Northeast China
    SUN Feng-hua, LI Li-guang, ZHANG Yao-cun
    2011, 31(8): 911-916. https://doi.org/10.13249/j.cnki.sgs.2011.08.911
    Download PDF ( )   Knowledge map   Save
    Based on air temperature and precipitation data in Northeast China during 1956 to 2007 as well as the related literatures at home and abroad, the key zone, key period and key factor influencing summer and winter air temperature and summer precipitation were analyzed and summarized. Summer precipitation often occurs in Northeast China under some circumfluence conditions, such as the polar vortex oscillation, the prevailing East Asia blocking high, the westward or northward subtropical high, the strong westerly jet center over Tibetan Plateau. On the other hand, low temperature in summer often appears in Northeast China when height field is negative anomaly over Iran high and South Asia high regions, polar vortex center intensity of last October is normal and strong, subtropical high intensity was weak and its location was eastward or southward in summer. Colder/warmer winter in Northeast China is related with the strong/weak Siberian high and Aleutian low, low/high prophase sea surface temperature of North Atlantic.
  • Urban Road Extraction of High Resolution Remote Sensing Based on Shape Reconstruction
    YANG Xian-wu, WEI Chun-tao, LI Cai-lu, WU Ping
    2011, 31(8): 917-921. https://doi.org/10.13249/j.cnki.sgs.2011.08.917
    Download PDF ( )   Knowledge map   Save
    In the high resolution remote sensing images, urban roads are the narrow areas that have the performance of local gray approximation and the width with slow change. The method of road extraction is proposed based on morphological reconstruction because of these morphological characteristics. Firstly, enhancing the original remote sensing image to highlight the image edge information, and making the enhanced image initial segmentation by the Otsu threshold segmentation method. Secondly, the original image is morphological reconstructed respectively by the different constructed markers according to the morphological characteristics of image elements, and the roads and buildings become the new image module. Lastly, the reconstructed road modules are contour extracted and refined for the road profile and centerline. Experimental results show that the method can effectively extract the urban road network from the high resolution remote sensing images.
  • Sedimentary Characteristics of Lacustrine Sediment Profile and Paleoenvironment in Mianchi Basin, Western Henan Province
    ZHAI Qiu-min, GUO Zhi-yong, SHEN Juan
    2011, 31(8): 922-928. https://doi.org/10.13249/j.cnki.sgs.2011.08.922
    Download PDF ( )   Knowledge map   Save
    In this paper, continuous sampling, grain size and total organic content(TOC) analysis have been done with the paleolacustrine sediment profile in Chidi Village, Mianchi Basin, combining with 14C dating and calibrating, the paleoenvironment in Mianchi Basin since the Last Glacial Maximum was reconstructed as follow: (1) During 19 543-9 240 cal. a B.P., the climate was dry and the lake was not formed; (2) During 9 240- 8 039 cal.a B.P., the climate turned to be warmer and humid, paleolake started to form;(3) During 8 039- 3 473 cal.aB.P., it was warm and humid in Lake Basin, and water level of the paleolake was the highest;(4) During 3 439-2 931 cal.a B.P., the climate change violently, in the whole period it was less warm and humid than before, water level of the paleolake decreased.(5) During 2 931-2 423 cal.a B.P., it was a dry and cold period with lower temperature and less precipitation, the paleolake gradually dried up. The evolution of human cultural in Mianchi Basin responded to climate change obviously, and was in correlation with the environment change.
  • Salinity Characteristics and Profile Types of Saline Soils in Low Plain Around Bohai Sea
    ZHOU Zai-Ming, ZHANG Guang-Hui, WANG Jin-Zhe, YAN Ming-Jiang
    2011, 31(8): 929-934. https://doi.org/10.13249/j.cnki.sgs.2011.08.929
    Download PDF ( )   Knowledge map   Save
    Aiming to characterize soil salinization, soil salinity profile types and distribution in the low plain around the Bohai Sea, soil samples were collected from 127 sites in the plain in this study. Soil samples in each site were taken from 0 cm to 60 cm in 5-cm or 10-cm increment, and soil salinity of each soil sample was analyzed based on the statistical method, principle component analysis method, hierarchical cluster analysis method and GIS technique. The results showed that the variations of soil salinity in the surface layer belonged to highly variation degree, soil salinity in other layers belonged to moderate variation degree in horizontal direction, while in the vertical direction, their differences are small. Soil salinity could be influenced by 5 principle components which were soil salinizaiton (principle component 1), soil alkalization (principle component 2), total regional dissolved soild, groundwater level (principle component 3, 5), source of kalium (principle component 4), and the cumulative contribution of these principle components added up to 87.88%. Hierarchical cluster analysis results indicated that salinity profile could be classified into 3 types, i.e. the top enrichment, the bottom enrichment and the middle enrichment. The percentage of each soil salinity profile type is almost equal, about 1/3. The top enrichment profile type is mostly distributed in the east coastal plain, the bottom enrichment profile type is mainly located in the inland low plain, while the middle enrichment profile type is distributed as map patches irregularly. Top enrichment profile type is the salinity accumulated state, on the contrary, the bottom enrichment profile is the desalinated state, while the middle enrichment profile type is the transitional sate between accumulation and desalination. The distributon patterns of salinity profile types reflected the effect of many factors to some extent.
  • Ecogeographical Distribution of Soil Fauna in Pinus koraiensis Mixed Broad-leaved Forest of Changbai Mountains
    YIN Xiu-qin, JIANG Yun-feng, TAO yan, AN Jing-chao, XIN Wei-dong
    2011, 31(8): 935-940. https://doi.org/10.13249/j.cnki.sgs.2011.08.935
    Download PDF ( )   Knowledge map   Save
    The Changbai Mountains, located in the Northeast China (41?23'-42?36'N, 126?55'-128?8'E), are rich in natural resources and have always been concerned by scientists. Soil faunas play crucial roles in forest ecosystem processes such as litter decomposition and nutrient mineralization, and also have effects on soil formation and quality. To understand the ecogeographical distribution of soil faunal community and provide the scientific basis for the conservation of forest ecosystems in Changbai Mountains, community composition, structure and biodiversity of soil fauna were investigated in top, typical and bottom distribution areas of Pinus koraiensis mixed broad-leaved forest of Changbai Mountain in July 2008. The sample area was 50 cm?50 cm for soil macrofauna and 10 cm?10 cm for soil meso-microfauna. Soil macrofauna was picked out by hands. Soil meso-microfauna was extracted by Tullgren funnel. All extracted soil samples were identified to the suborder or family level under a stereoscopic microscope. Soil pH was measured with PHS-3B acidity meter. Soil organic C was determined by K2Cr2O7 oxidation method and total N by Kjeldahl method. Total P was analyzed by using the colorimetric method with molybdenum in sulphuric acid. Total K was determined with flame photometer. A total of 39 groups, 6 124 individuals of soil fauna were obtained and fell into 3 phylum, 6 classes, 17 orders. Oribatida, Actinedida and Isotomidae were the dominant groups. There were 5 common groups, involving Hypogastruridae, Pseudachorutidae, Gamasida, Entomobryidae and Tomoceridae, and 31 rare groups in the collection. Results showed that there was significant difference in the individual numbers of soil fauna between typical and bottom (p<0.05) distribution areas, while group numbers of soil fauna were no significant difference among top, typical and bottom distribution areas of Pinus koraiensis mixed broad-leaved forest. The highest community diversity and evenness of soil fauna was recorded in typical distribution area. Group and individual numbers of soil fauna decreased with the increase of soil layer depth in a vertically distribution, which was significant in top and typical distribution areas. There were greater correlation coefficient among Oribatida, Actinedida, Isotomidae, Hypogastruridae, Gamasida and Pseudachorutidae, and they were all found in three distribution areas at the same time, and individual numbers of them were also more than others. The pH,organic matter, total P, total K and total N of soil had effects on the composition of soil fauna community. The difference in total K, total N, total P and organic matter content were significant in 0-30 cm soil layers among top, typical and bottom distribution areas of Pinus koraiensis mixed broad-leaved forest (p<0.001). Grey relevant analysis showed that total K, total N and organic matter content had more effects on the composition of soil fauna than pH and total P of soil. Environment factors had different effects on the key soil fauna community.
  • Characteristics of Soil Salinization of Huanghe River Delta in Different Periods
    XU Qin-mian, YUAN Gui-bang, SUN Yun-xia, HU Yun-zhuang, ZHANG Yu-fa
    2011, 31(8): 941-946. https://doi.org/10.13249/j.cnki.sgs.2011.08.941
    Download PDF ( )   Knowledge map   Save
    On the west coast of Bohai Bay, eight soil profiles have been selected in different geomorphologic units and land use, and the samples of salinized soil at 0-20, 20-40, 40-60 and 60-90 cm under the ground were collected. The soil salinized slightly in paleo-river highland, belonged to sulphate type and chloride-sulphate type of soil saline. The soil salinized moderately in influve, and been belonged to sulphate-chloride type of soil saline. The soil of super-intertidal flat is saltierra, and its salinity reach 0.7-1.1 (g/kg), and belonged to chloride type soil saline. Evaporation and eluviation of soil have been closely related with geomorphologic units and sedimentary frame. The soil of far away the sea has higher content of HCO3-, and lower content of Cl- and salinity in the same geomorphologic units.
  • Risk Evaluation and Influence Analysis of Flowing Backward From Main Stream in Xiaobei of Huanghe(Yellow) River to Lower Reacher of Weihe River
    LI Jing-yi
    2011, 31(8): 947-951. https://doi.org/10.13249/j.cnki.sgs.2011.08.947
    Download PDF ( )   Knowledge map   Save
    Risk evaluation of flowing backward from the main stream in Xiaobei of the Huanghe (Yellow) River to the lower reacher of the Weihe River has become the significant work of flood prevention because of the dangerous situation of the flowing backwark. Based on the contrast of historical observed data and remote sensing images, using the inserting value calculation method, risk degree of flowing backward was evaluated and zoned. The results are as follows: 1) It is obvious that the larger the flood of the Huanghe River, the larger the area of inversely flow deposition, and the more the water level in the reaches of the Weihe River, vice versa. 2) The highest risk regions usually located in the eastness of Dali near by the main stream in Xiaobei of the Huang River and the riverside regions of Tongguan, Huayin, Huaxian, Weinan and Lintong. The higher risk regions are located in the northeastern part of Dali and the common boundary of Weinan and Lintong on the southness shore of mainstream watershed of the Weihe River. Then, the remainder is lower risk regions. 3) Westward moving of the estuary of the Weihe River to the Huang River and flowing backward are the cause-and-effect, which not only resultd in shrinking of the riverbed at the lower reaches of the Weihe River, but also reducing the ability of flood transflux. So there is a complexion of small flux, high water level and big disaster. 4) In order to reduce the risk degree of flowing backward, as the given result, the district regionalism and local protection must be broken to implement the integrated program of the watershed and to decline the Tongguan stage to stabilize the physiognomy at the estuary of the Weihe River to the Huang River.
  • Tendency and Driving Forces of Runoff Changes for Upper Stream of Naoli River in the Sanjiang Plain
    LIU Gui-Hua, LUAN Zhao-Qing, YAN Bai-xing, GAO Chang-Jun
    2011, 31(8): 952-957. https://doi.org/10.13249/j.cnki.sgs.2011.08.952
    Download PDF ( )   Knowledge map   Save
    In this paper, the non-parametric Mann-Kendall test was used to analyze the tendency of runoff changes for upper stream of Naoli River in the Sanjiang Plain in 1956-2002, the abrupt change of runoff occurred in 1966 and the watershed runoff was divided the into two stages, that is, 1956-1966 and 1967-2002. The coefficient of variation was applied to testing the effect of the climatic element on the runoff reduction. The conclusions are arrived that the climatic factor is the main reason causing the reduction of runoff in the first stage while the human activities made the runoff decrease abruptly in the second stage. The IHACRES model was used to simulate the runoff in 1967-2002 and calculate the runoff reduced by human events. The results show that 11 years of the gauged annual runoff reduced more than 50% compared with the reference annual runoff in the second stage, and of which 10 years reduced from 30% to 50% and 11 years reduced from 10% to 30%, respectively.
  • Variation of Grain Size on Surface of Barchans in Mainling Great Valley, Yarlung Zangbo River
    ZHOU Na, ZHANG Chun-lai, LIU Yong-gang
    2011, 31(8): 958-963. https://doi.org/10.13249/j.cnki.sgs.2011.08.958
    Download PDF ( )   Knowledge map   Save
    The aeolian sand belts are distributed extensively in Mainling great valley section of the Yarlung Zangbo River. Each belt can be divided into eroded area, erosion and deposition transition area, and deposition area by distinct aeolian sand activities. The two belts with aeolian sand activity were studied. The results show that sediments of the dune are mainly composed of fine sands with moderate sorting, fine skewness, and muti-modal grain size distribution. Grain size distribution on the surface of barchans can be attributed to the 'dune crest coarser’pattern as a whole with limited exception where grain size distribution shows a "finer crest" pattern. Spatial variations of grain size distribution among the barchans within the same aeolian sand belt were shown. Small barchans developed in the eroded area exhibit finer grain size, poor sorting, very fine skewness and multi-mode. In the erosion and deposition transition area and downwind deposition area, dune grain size becomes coarser with sorting better, fine skewness converting to nearly symmetry, and muti-mode grain size distribution pattern turning to be uni-mode.
  • The Development Characteristics and Geomorphologic Age of Zhangshiyan Landform
    CHEN Li-jiang, XU Quan-hong, ZHAO Yan-xia, LI Qing-chen, ZHANG Jing-fang
    2011, 31(8): 964-968. https://doi.org/10.13249/j.cnki.sgs.2011.08.964
    Download PDF ( )   Knowledge map   Save
    Under the control of stratigraphic trend, structure and lithology, there are two slope development modes during the development progress of Zhangshiyan Landform marked with the long red cliff, which are the wedge-shaped lateral cutting mode with cutting the cliff to form lane valley, and the horizontal digging mode with digging horizontally at the foot of the cliff to form rock porch leading to the cliff collapse back. The lane valley, rock porch and the Ω-shaped valley have the respective self-similarity features in different location or scale. The cycle of Zhangshiyan Landform development is 294.7×104a. It can be divided four stages: infancy stage lasted for as long as 8.3×104a, young stage 83.2×104a, robust stage 115.2×104a and old stage 88×104a. In Zhangshiyan region, Zhangshiyan landform is layered clearly, caused by hard stratum alternating with soft stratum but not the different stages of Zhangshiyan landform.
  • Quantification and Semi-quantification of Iron-oxide Minerals in Aerosol Particles in the Hinterland of Taklimakan Desert
    LU Hui, WEI Wen-shou, LIU Ming-zhe, WU Xin-ping, MU Shu-yong, HAN Xi
    2011, 31(8): 969-975. https://doi.org/10.13249/j.cnki.sgs.2011.08.969
    Download PDF ( )   Knowledge map   Save
    By scattering and absorbing solar and telluric radiation, dust aerosol has a direct impact on the Earth’s radiative balance. Their quantification is of utmost importance to assess the desert dust optical properties. Iron oxides minerals (especially hematite and goethite) contents are very low in aerosol particles, which are strong absorbers at ultra-violet and visible wavelengths. CBD method and diffuse reflectance are adapted to quantify and semi-quantify the free-iron oxides contents in the aerosols collected at Tazhong on 9-11 April, 2006 in the Hinterland of Taklimakan Desert. For these samples, the percentage of free-iron relative to the total estimated aerosol mass increased from 4.55% to 8.16% with an average of 6.36%. Total-iron content, free-iron content and free-to-total iron ratio are 5.16%, and 0.32%, respectively. The first derivatives of the reflectance spectra are consistent with signals from two iron-oxide minerals, hematite and goethite, at wavelengths of 560 nm and 435 nm, respectively.
  • The Remote Sensing Investigation and Causal Analysis of Salt-affected Soils in the Weigan-Kuqa Reiver Delta
    Mamatsawut, Tashpolat·Tiyip, DING Jian-li, Kaoru Kashima
    2011, 31(8): 976-981. https://doi.org/10.13249/j.cnki.sgs.2011.08.976
    Download PDF ( )   Knowledge map   Save
    In this paper, the Decision Tree method was used to classification of salt affected soil in Weigan-kuqa river delta oasis with the integration of high spatial resolution ALOS image and the ancillary data such as geologic maps, soil maps, groundwater table and quality data, based on their characteristic.The amount, spatial distribution, extent and center of salt affected soils in the study area was indicated, and the causal analysis of the salinization was discussed. The result showed that the total accuracy of Decision Tree classification is 91.3569%, testifying it is a very useful method for monitoring soil salinization in the arid area. The salt affected soils are mostly distributed the lower reaches of Weigan river and Kuqa river d, the north of the Tarim river and the southeast, south, east and southeast of the Weigan-Kuqa river oasis. The proportion of the salt affected soils in the study area is very high, among them Kuqa County is severely salinized, Shaya County is moderately salinized, Xinhe County is slightely salinized. The salinization in the study area was mainly due to the drought climatic conditions, rich salt origins, enclosed basin, fragile water cycle system and unreasonable human activities.
  • The Spatial Distribution of Soil Organic Carbon Storage and Change under Different Land Uses in the Middle of Heihe River
    ZHANG Jun-hua, LI Guo-dong, NAN Zhong-ren, XIAO Hong-lang, ZHAO Zi-sheng
    2011, 31(8): 982-988. https://doi.org/10.13249/j.cnki.sgs.2011.08.982
    Download PDF ( )   Knowledge map   Save
    Spatial distribution of soil organic carbon density, storage and its change are researched under different land uses in the middle of Heihe River, based on the multi-methods of gathering field samples, laboratory analysis, GIS spatial analysis model and remote sensing. The results show that obvious spatial otherness of total soil carbon (TOC), active organic carbon (AOC), nonactive organic carbon (NOC) exist under different land uses. NOC density is consistent with TOC, but density of AOC is different. It indicates that impacts of land use changes on TOC, AOC and NOC are different. According to the calculation result, storage of TOC, AOC and NOC is 94.72 Tg, 45.12 Tg and 49.60 Tg in 1m depths, respectively. AOC account is for 47.63% and NOC is 52.36%. It’s found that the relationship between SOC and influencing factors is more authentic if AOC and NOC are introduced.
  • Change of Terrestrial Surface Potential Evapotranspiration for the Growth Period in Loess Plateau
    YAO Yu-bi, WANG Run-yuan, YANG Jin-hu, LU Deng-rong, XIAO Guo-ju, WANG Yao, LIU Lin-chun
    2011, 31(8): 989-995. https://doi.org/10.13249/j.cnki.sgs.2011.08.989
    Download PDF ( )   Knowledge map   Save
    Based on climatological data in Loess plateau from 1961 to 2008, the potential evapotranspiration of the growth period was computed by using revised Penman-Monteith Model. The spatial-temporal distribution, anomaly distribution and sub-regional temporal variations of the potential evapotranspiration in the growth period were analyzed at the same time. The results showed that the main spatial model of annual potential evapotranspiration of the growth period in Loess plateau is consistent anomaly distribution. In northwest regions of Loess plateau, the potential evapotranspiration of the growth period displayed a significant ascending trend and showed an abrupt change; in northeast and southeast regions of Loess plateau, the potential evapotranspiration of the growth period displayed a significant descending trend and showed an abrupt change too. In all these three regions, the potential evapotranspiration of the growth period shows an obvious fluctuating period of 3-4years.
  • A Contrast Introduction to Danxia Landforms from a World-wide References for Similar Landforms
    OUYANG Jie, ZHU Cheng, PENG Hua
    2011, 31(8): 996-1000. https://doi.org/10.13249/j.cnki.sgs.2011.08.996
    Download PDF ( )   Knowledge map   Save
    The term "Danxia Landform" was first identified and coined in China. Danxia Landform research in China is focused on primary theoretical research, scientific discussions of macro spatial distribution and qualitative description of the classification. New studies have recently been concerning quantitative,visualization and experimental research for Danxia Landform. Other countries do not currently refer to Danxia Landform as a reference for this unique type of landform very frequently, but foreign scholars have abundant research in sandstones, conglomerates, and red beds in micro, experiments, and quantitative areas. For comparisons with national and international research, Danxia Landforms should be applied as a primary example of macro and micro, qualitative and quantitative, theoretical and practical descriptions and analysis. It is instructive to use the term "Danxia Landform" as an acceptable international term when comparing and contrasting with other like landforms around the world.
  • Spatial Variation of Soil Nutrients in Downstream Districts of Beiyunhe River Using Geostatistical Methods
    LI Jian-hui, LI xiao-xiu, ZHANG Wang-shou, WANG Xiao-yan
    2011, 31(8): 1001-1006. https://doi.org/10.13249/j.cnki.sgs.2011.08.1001
    Download PDF ( )   Knowledge map   Save
    In this paper, based on samples from the downstream district along the Beiyunhe River, the soil nutrients such as pH, available nitrogen, available phosphorus, available potassium, and organic matters were analyzed by the geostatistical method. Combined with the basic data of Wuqing’s soil type, the relationship of the different nutrients’spatial distribution was found that the spatial distributions of the pH and available phosphorus are similar to the soil type more or less, and the reason is that soil pH and available phosphorus are influenced by the soil type, and the effect on soil pH is significant; Beiyunhe river system has a great influence to the spatial distribution of available nitrogen and organic matters, the contents of which in high-density river system regions were significantly higher than those in lower-density river system regions. Available K mostly caused by other factors.
  • Spatio-temporal Trends of Annual Extreme Temperature in Northern and Southern Qinling Mountains
    ZHANG Li-wei, SONG Chun-ying, YAN Jun-ping
    2011, 31(8): 1007-1011. https://doi.org/10.13249/j.cnki.sgs.2011.08.1007
    Download PDF ( )   Knowledge map   Save
    With global climate warming, the research on regional extreme climate change has remarkable significance. This paper, based on the meterological data of the 60 stations in Qinling Mountains, analyzed the spatio-temporal characteristics of average, extreme high and low temperature in northern and southern Qinling Mountains, using Mann-Kendall mutation test and Kriging interpolation. The results showed that the order of climate trend rate of average annual temperature is that the southern part of Shaanxi < Guanzhong < other regions of China;the relationship of climate trend rate of annual high temperature is that: Guanzhong < other regions of China < the southern part of Shaanxi. The order of climate of extreme low temperature is that the southern part of Shaanxi ≈Guanzhong < other regions of China. The mutation year of average annual temperature in the two areas was 1997, which is later than the other regions of China. But, extreme high temperature fluctuation is not significant. At the same time, the mutation year of extreme low temperature in the two areas was 1978. Qinling Mountains have the important geographical feature dividing line effect. The spatial distributions of average and extreme low temperature in the areas of Qinling Mountains display that the high temperature is in the southern area, but the slow temperature in the northern area, which are distributed along the latitudinal. Contrarily, the spatial distribution of extreme high temperature shows that it is high in the eastern area, but low one in the western area, which are distributed through the longitude.
  • Cultivated land Quality Evaluation Methods Based on Bio-Norm and EO
    ZHANG Guang-xing, YU Dong-sheng, ZHANG Zhong-qi, WANG Xing-xiang, SHI Xue-zheng
    2011, 31(8): 1012-1018. https://doi.org/10.13249/j.cnki.sgs.2011.08.1012
    Download PDF ( )   Knowledge map   Save
    Quality evaluation of cultivated land is important in the guidance of agricultural production. Whether the evalution method is appropriate or not directly affects the scientificity of evaluation results. Through practical investigation, sample collection, and analysis, a total of 249 surficial paddy soil property data and 95 rice production data were collected in the study area of Yujiang County, Jiangxi Province. Expert opinion and the newly established Bio-Norm method were used to determine indicators, indicators’weight, and their relationship functions respectively, and then to evaluate the quality of paddy field land of the study area. The comparison between Bio-Norm method and EO showed that EO method was unstable, and the indicators selected by Bio-Norm method were more representative than that of EO method. The weights obtained from Bio-Norm method could better accurately reflect the importance of indicators. The relationship functions of Bio-Norm method could better reflect the actual requirements of rice growth. Evaluation results showed that regression coefficient of determination (R2) between cultivated land quality index (IIFI value) obtained from Bio-Norm method and rice yield was far higher than that of EO method, and the distribution of IIFI value obtained from Bio-Norm method and rice yield was more consistent in the region than that of EO method. Therefore, the Bio-Norm method is more scientific and reasonable than the EO method in evaluating the quality of cultivated land.
  • Changes of Vegetation Coverage During Recent 18 Years in Lianjiang River Watershed
    GAN Chun-ying, WANG Xi-zhi, LI Bao-sheng, LIANG Zhao-xiong, LI Zhi-wen, WEN Xiao-hao
    2011, 31(8): 1019-1024. https://doi.org/10.13249/j.cnki.sgs.2011.08.1019
    Download PDF ( )   Knowledge map   Save
    With TM images as a data source, this paper calculates and analyses the characteristics of change and spatial distribution about the vegetation in Lianjiang watershed in 1988-2006 by using the dimidiate pixel model based on NDVI. Overlaying the vegetation coverage map and the sub-karst geological map, the impact on vegetation coverage exerted by geological structure is analyze. The results can be described in the following three aspects. 1) Because of the effect of climate and human activities, the vegetation coverage in Lianjiang River watershed got a rise in 1988-2006. The area of higher and high vegetation coverage districts increased, while that of low, lower and middle vegetation coverage districts decreased. 2) The quality of vegetation in non-karst district was better than that in karst district due to the influence of geological formation. 3) The change of vegetation coverage’s spatial distribution was significant in Lianjiang River watershed during the recent 18 years.