Man-Zhi Tan

Chinese Academy of Sciences, Beijing, Beijing Shi, China

Are you Man-Zhi Tan?

Claim your profile

Publications (4)0.5 Total impact

  • Article: Visualization of uncertainty associated with spatial prediction of continuous variables using HSI color model: a case study of prediction of pH for topsoil in peri-urban Beijing, China
    Man-zhi Tan, Jie Chen
    [show abstract] [hide abstract]
    ABSTRACT: Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of topsoil in the peri-urban Beijing. A two-dimensional legend was designed to accompany the visualization—vertical axis (hues) for visualizing the predicted values and horizontal axis (whiteness) for visualizing the prediction error. Moreover, different ways of visualizing uncertainty were briefly reviewed in this paper. This case study indicated that visualization of both predictions and prediction uncertainty offered a possibility to enhance visual exploration of the data uncertainty and to compare different prediction methods or predictions of totally different variables. The whitish region of the visualization map can be simply interpreted as unsatisfactory prediction results, where may need additional samples or more suitable prediction models for a better prediction results.
    Journal of Forestry Research 04/2012; 19(4):319-322.
  • Source
    Article: Classification of cryosols: Significance, achievements and challenges
    [show abstract] [hide abstract]
    ABSTRACT: International concerns about the effects of global change on permafrost-affected soils and responses of permafrost terrestrial landscapes to such change have been increasing in the last two decades. To achieve a variety of goals including the determining of soil carbon stocks and dynamics in the Northern Hemisphere, the understanding of soil degradation and the best ways to protect the fragile ecosystems in permafrost environment, further study development on Cryosol classification is being in great demand. In this paper the existing Cryosol classifications contained in three representative soil taxonomies are introduced, and the problems in the practical application of the defining criteria used for category differentiation in these taxonomic systems are discussed. Meanwhile, the resumption and reconstruction of Chinese Cryosol classification within a taxonomic frame is proposed. In dealing with Cryosol classification the advantages that Chinese pedologists have and the challenges that they have to face are analyzed. Finally, several suggestions on the study development of the further taxonomic frame of Cryosol classification are put forward.
    Chinese Geographical Science 04/2012; 13(4):352-358. · 0.50 Impact Factor
  • Article: [Spatial correlation between non-agricultural land expansion and soil quality in Suzhou City].
    [show abstract] [hide abstract]
    ABSTRACT: Based on the layer of non-agricultural land expansion interpreted from 4 Landsat TM images in 1984, 1995, 2000 and 2003 and the soil quality map, the patterns of non-agricultural land expansion occurring on soil quality levels in Suzhou City were analyzed. It was indicated that the non-agricultural land expansion happened mainly on the soils with high quality during 1984-2003. 90% of the expansion took place on the soils with moderately high quality (grade 2), and the next was those with high quality (grade 1). In the meanwhile, the expansion on the soils with moderate (grade 3) and low quality (grade 4) was only less than 1% of total area. From the viewpoint of soil quality, we should ponder more over the opinion on "dynamic balance of total amount of arable land between occupying and supplementing".
    Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban 01/2008; 18(12):2835-40.
  • Article: Spatial Prediction of Heavy Metal Pollution for Soils in Peri-Urban Beijing, China Based on Fuzzy Set Theory
    [show abstract] [hide abstract]
    ABSTRACT: Fuzzy classification combined with spatial prediction was used to assess the state of soil pollution in the peri-urban Beijing area. Total concentrations of As, Cr, Cd, Hg, and Pb were determined in 220 topsoil samples (0–20 cm) collected using a grid design in a study area of 2600 km2. Heavy metal concentrations were grouped into three classes according to the optimum number of classes and fuzziness exponent using the fuzzy c-mean (FCM) algorithm. Membership values were interpolated using ordinary kriging. The polluted soils of the study area induced by the measured heavy metals were concentrated in the northwest corner and eastern part, especially the southeastern part close to the urban zone, whereas the soils free of pollution were mainly distributed in the southwestern part. The soils with potential risk of heavy metal pollution were located in isolated spots mainly in the northern part and southeastern corner of the study region. The FCM algorithm combined with geostatistical techniques, as compared to conventional single geostatistical kriging methods, could produce a prediction with a quantitative uncertainty evaluation and higher reliability. Successful prediction of soil pollution achieved with FCM algorithm in this study indicated that fuzzy set theory had great potential for use in other areas of soil science.
    Pedosphere.

Institutions

  • 2012
    • Chinese Academy of Sciences
      • Graduate School
      Beijing, Beijing Shi, China
    • Institute of Soil Science - Chinese Academy of Sciences
      Nanjing, Jiangsu Sheng, China