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Pedodiversity: a controversial concept

CHEN Jie,ZHANG Xue-lei,GONG Zi-tong,WANG Jun,

地理学报 , 2001,
Abstract: The concept of pedodiversity and its measurement methodology proposed and developed by Ibá?ez research term is introduced. An attempt to apply pedodiversity to analyze spatial soil variation and distribution patterns on the global scale is briefly demonstrated. Furthermore, constructive comments and criticisms on pedodiversity and its measurement from the noted pedologists and ecologists are outlined. Finally, potential applications of pedodiversity in soil science and other relevant disciplines are discussed.
月壤及模拟月壤微观结构的研究  [PDF]
岩土力学 , 2012,
Abstract: 为了对比研究月壤与模拟月壤的微观结构,介绍了月壤的形成作用过程和5种基本颗粒类型;通过真实月壤照片,对月壤微观结构进行了分析;利用火山灰为模拟月壤主体材料,对其成分进行了检测;对模拟月壤的火山灰颗粒进行了显微图像分析试验。结果表明,月壤存在胶结物微观颗粒,胶结物颗粒具有分支的组织形态和封闭的气泡,并且有金属铁珠存在;火山灰所含的主要成分及含量与月壤相似,经过粉碎的火山灰试样棱角较为明显,其纵横比峰值略小,稍显长条状,但与月壤比较相近,而复杂度因子则略有欠缺,说明颗粒还不够粗糙和多棱
Rényi dimensions and pedodiversity indices of the earth pedotaxa distribution
F. J. Caniego, J. J. Ibá ez,F. San José Martínez
Nonlinear Processes in Geophysics (NPG) , 2007,
Abstract: Pedodiversity, the study and measurement of soil diversity, may be considered as a framework to analyze spatial patterns. Recently, selfsimilar multifractal patterns have been recently reported in the pedotaxa-abundance distributions at the planetary scale. This is the result to be expected from the complexity of earth soil systems. When the state of soil is understood as the outcome of nonlinear chaotic dynamic, highly irregular patterns with so-called multifractal behavior should be common. This opens the opportunity to use parameters of fractal theory to characterize pedodiversity. We compute Rényi generalized dimensions for the abundance distribution of pedotaxa for the five landmasses and the whole World drawn from the most detailed available global dataset based on the second level of the FAO 1974 classification units. We explore the effective relationship between diversity indices and Rényi dimensions. We show how multifractal analysis unifies diversity indices and how they should be interpreted offering a coherent perspective with a single mathematical procedure to analyze spatial patterns of the pedosphere.
A preliminary study of OCPs in underground river surface sediments from Chongqing typical karst areas

Yang Mei,Pu Junbing,Zhang Junpeng,Hu Zhiyong,

环境工程学报 , 2009,
Abstract: 19 kinds of organochlorine pesticides(OCPs)in surface sediments of Chongqing karst areas were analyzed by GC-ECD.The total concentration range of OCPs was 4.73~286.03 ng/g,the concentration range of DDTs was 0.35~181.78 ng/g and the concentration range of HCHs was nd~23.53 ng/g.Compared with other rivers,the organchlorine pesticides in sediments of Chongqing typical karst areas is in the high level.DDE/DDD demonstrates DDT degraded in the aerobic environment except Jiangjiarongdong.(DDD+DDE)/DDTs shows no n...
The Economy Evaluation of the Counties in Chongqing  [PDF]
Journal of Chongqing Normal University , 2012,
Abstract: The paper based on the relevant data of Chongqing Statistical Yearbook 2011, 40 districts and counties of Chongqing's economic development in 2010 was evaluated. According to their own situation in Chongqing indicators, the paper selects nine indicators: total population of year-end, gross regional product, per capita disposable income of urban residents, total fixed asset investment, district local fiscal revenue, the expenditure of the local district, total retail sales of social consumer goods, gross industrial output value,import and export value and translates them intoF1 . Based on principal component analysis, we set the formulaF = (70.145% F1 +13. 937F2 ) / 84.082%, so we set the indicators system of evaluation for Chongqing forty rural economic development. It shows that anhour economic area is better than the northeast of Chongqing, and the northeast of Chongqing is better than the southeast of Chongqing overall, among which Yubei district is the best in an hour economic areas, Wanzhou district is the best in the northeast of Chongqing,and Qianjiang district is the best in the southeast of Chongqing.
Impact of urbanization on pedodiversity in Suzhou area

SUN Yanci,ZHANG Xuelei,CHEN Jie,

应用生态学报 , 2005,
Abstract: Based on the TM remote sensing information of 1984, 1995, 2000 and 2003, this paper quantitatively analyzed the spatial-temporal dynamic changes of pedodiversity in Suzhou area under quickly growing urbanization. The results showed that in this area, clay loamy typic-hapli-stagnic anthrosol and fine sand clay loamy typic-hapli-stagnic anthrosol were the predominant soil types, but their distribution area decreased 5.11% and 3.14%, respectively, in latest 20 years. Jinchang, Pingjiang and Canglang Districts were the focuses of urbanization in Suzhou area, where pedodiversity changed furiously. During 1984 approximately 2003, more than 90% of the clay loamy typic-hapli-stagni gleyosol in Pingjiang District and sandy calcaric-mottlic-udi-orthic primosol in Taicang City were almost disappeared, and changed into residential area. Statistical analysis showed that urbanization had a significant impact on pedodiversity, and was the prime driving force on the pedodiversity in Suzhou area.
Impact of land cover types on the soil characteristics in karst area of Chongqing

LI Yangbing,XIE Deti,WANG Shijie,WEI Chaofu,

地理学报 , 2006,
Abstract: The 26 plots including natural forestland, secondary forestland, shrub-grassland, sloping cropland, artificial forest and abandoned field, were selected to discuss the impact of land cover on the soil characteristics in the three karst districts of Chongqing. The results showed that: (1) After the vegetation turned into secondary vegetation or artificial vegetation, or reclamation, soil physical properties would be degraded. In the surface-layer soil of sloping cropland, the contents of > 2 mm water-stable aggregates decreased obviously with apparent sandification. (2) The contents of soil organic matter and total nitrogen are controlled completely by vegetation type and land use intensity. The increasing trend is rather slow in the early days when over-reclamation is stopped and the land is converted to forest and pasture. (3) Herbaceous species increase and woody plants species decrease with the increase of land use intensity, therefore, the soil seed banks degrade more seriously. (4) The soil degradation index has been set up to describe the relative soil degradation degree under the conditions of different vegetation types. (5) Land cover has a significant effect on karst soil characteristics, land degradation in the karst ecosystem is essentially characterized by the different degradation of soil functions that serve as water banks, nutrient banks and soil seed banks.
模拟月壤研制的初步设想  [PDF]
空间科学学报 , 2005,
Abstract: 模拟月壤是月球样品的地球化学复制品.作者总结世界上已有的5种模拟月壤JSC-1,MLS-1,MLS-2,MKS-1和FJS-1的研制过程、方法与基本理化性质.认为系列化模拟月壤研制对中国首次月球探测有重要意义.在此基础上,作者提出系列化模拟月壤研制的基本思路.
钻进取样试验用模拟月壤  [PDF]
地质与勘探 , 2012,
Abstract: 钻具在月壤中进行钻进取样,是一个钻具与月壤相互作用的过程。为获得可靠的月壤钻具,在其研制过程中应在月壤里进行钻进试验。但地球上的真实月壤很珍贵,难以满足钻进试验的需要。采用能够较好地模拟真实月壤主要物理力学特性的模拟月壤,代替真实月壤进行钻进取样试验,是月壤钻具研制的一个必要手段。国外已对月壤进行了大量的研究,并取得了丰富的成果。本文在对真实月壤以及模拟月壤研究进行总结的基础上,对月壤钻具研制中所需的模拟月壤进行了简要的阐述,可供月壤钻具研制参考。
微生物学通报 , 1982,
Abstract: 我们从1978年开始,利用庆丰霉素防治蚜虫。现将结果报道如下。材料和方法
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