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81.
Jin-Soo Lee Kyung-Seok Ko Tong-Kwon Kim Jae Gon Kim Seong-Hyun Cho In-Suk Oh 《中国地球化学学报》2006,25(B08):152-152
The regional survey of groundwater used as a small water supply system was performed to know the effect of geology, soil properties and land use on groundwater quality at Nonsan City, Korea. A total of 126 groundwater samples were collected and analyzed at the study area. The multivariate statistical methods, principal components analysis and discriminant analysis, and GIS technique were used for the quantitative interpretation of groundwater quality. The study area is mainly composed of Precambrian gneiss, Jurassic granite, and Cretaceous volcanics, and metasedimentary rocks of the Ogcheon zone. The land use was grouped as paddy, upland, grassland, resident, point source, industrial area, and water system. The soil properties were classified as 4 major groups, Entisols, Alfisols, Inceptisols, and Ultisols, by the degree of development, and reclassified as 11 subgroups. The modified and simplified geologic map, soil map, and land use map were made by using ARCGIS soft-ware. The area of geology, soil property, and land use affecting the groundwater quality for each well were also calculated by ARCGIS soft-ware to acquire the quantitative parameters for multivariate statistical analysis. The monitoring results of groundwater in the study area showed that 13%-21% of the groundwater samples exceeded the portable water guideline and the main causes were turbidity, bacteria, arsenic and nitrate-N. The spatial distribution of each component showed the close relationship between groundwater quality and geology reflecting the topography, land use. 相似文献
82.
83.
Ir. Lahuddin M S Zulkifli Nasution 《湿地科学》2006,4(3):161-167
1 INTRODUCTIONQuality of chemical properties of flooded soils isgenerally determined by salinity and alkalinity,bothof these acts as inhibiting factors of plant growth.Thecorrelation of electrical conductivity and other analysisindex has been reported by … 相似文献
84.
Yaping WANG Chunxue XU Ziyi AN Suming WANG 《中国地球化学学报》2006,25(B08):205-205
Different species of one element have different activities, so it has different effects on environment and human health. To analyze qualitatively and quantitatively the speciation of a special element in sample, which is the important basis for appraising the toxicity and studying the rule of transfer and translation of elements. Since the 1970's, the scheme of sequential extraction has already been used at many laboratories both at home and abroard, to get the information about heavy metals' activity in polluted soils. Because this method has the experimental nature, many schemes of problem has taken place, the absence of consistency of these sequential extraction have been formed. Thus the complexity of the schemes, the lack of selectivity of reagent, the lack of quality control, the result mainly related to the extraction scheme used, and so on. In the face of these problems, the study of experimental methods of sequential extraction on three different soils, sediment in Dongting Lake, soil in Jiangsu Province and loess in Shanxi Province was made. Reference materials of heavy metal speciation following sequential extraction in soil and sediment had been developed. Nowadays two kinds of sequential extraction methods which are widely used are BCR (three steps) and improved Tessier methods (seven steps). Based on three steps of BCR, water-soluble speciation and the residual speciation were increased in our research. BCR701 was determined eight times at different laboratories using BCR three steps. The results showed that determined data obtained eight times were identical to the standard value, and it is indicated that this method has good reproducibility. The stability and homogeneity experiments indicated that the preparation of three types of candidates accorded with our requirements. Eight laboratories had afforded the determined values of 12 heavy metal elements (Cu, Pb, Zn, Mn, Co, Ni, Cd, Cr, Mo, As, Sb, Hg, Se et al.) using BCR three steps. Also, these three candidates afforded the determined values by seven steps, and 12 laboratories had participated. 相似文献
85.
86.
Xinbin FENG Shaofeng WANG Guangle QIU Yamin HOU Shunlin TANG 《中国地球化学学报》2006,25(B08):243-244
Guizhou is located in the Circum-Pacific Global Mercuriferous Belt, and mercury concentrations in soil in this area are enriched. In-situ total gaseous mercury (TGM) exchange fluxes between air and soil surface were intensively measured at four sampling sites in Guiyang from 21 May to 16 June, 2003, and five sites in the Lanmuchang mercury mining area in December 2002 and May 2003, respectively. The in-situ Hg flux measurement was conducted with a dynamic flux chamber (DFC) of quartz. Overall, net emissions were obtained from all sampling sites. Soil mercury concentration and solar radiation have been proved to be the two most important parameters to control mercury emissions from soil. Meanwhile, rain events can enhance mercury emission rate significantly. 相似文献
87.
Shaoqi ZHOU Weidong LU 《中国地球化学学报》2006,25(B08):252-253
Mixture of municipal sewage sludge and organic garbage, which was alternatively treated by aerobic and anaerobic composting technologies for 60 days. The characteristics of the compost are as follows: the total nitrogen (TN), total phosphors (TP) and total potassium (TK) are 1.40%, 0.101% and 1908.32 mg/kg on dry weight basis, the contents of Cu, Ni, Cd, Cr, Pb and Zn are 131.23, 21.49, 1.31, 35.49, 72.50 and 616.76 mg/kg on dry weight basis. A basin-scale experiment was carded out by planting watercress with kailyard soil fertilizing with the compost, the results showed that the municipal sewage sludge and organic garbage compost could promote the production of watercress to different degrees, the crop biomass increased from 74.46% to 312.00% with the amount of compost fertilizing on the kaliyard soil while the amount of compost fertilizing on the kaliyard soil below 150 g per 3.75 kg kaliyard soil and decreased from 312.00% to 102.29% while the amount of compost fertilizing on it over 150 g per 3.75 kg kaliyard soil, so the optimal addition of compost in the watercress and soil was 150 g compost per 3.75 kg kailyard soil. Furthermore, 相似文献
88.
A numerical procedure is described for the analysis of the vertical deformation and the stress distribution of the strip footings
on layered soil media. Three layers of soil with different stiffness are considered with the middle soil layer the thinnest
and most stiff layer. The soil media is discretized and using the theory of elasticity, the governing differential equations
are obtained in terms of vertical and horizontal displacements. These equations along with appropriate boundary and continuity
conditions are solved by using the finite difference method. The vertical and horizontal displacements, strains and stresses
are found at various nodes in the soil media. Parametric studies are carried out to study the effect of the placement depth
of the middle soil layer, the relative ratios of the moduli of deformation of the soil layers on the vertical displacement
of the footing and the vertical stress distribution. These studies reveal that the middle thin but very stiff layer acts like
a plate and redistributes the stresses on the lower soft soil layer uniformly. The displacement on the top and bottom of the
middle soil layer is almost the same showing that the compression of the middle layer is negligible as it is very stiff. 相似文献
89.
Shubhra Goel Shalini Nihar Ranjan Patra 《Geotechnical and Geological Engineering》2006,24(6):1511-1525
Inclined anchors are widely used in a variety of civil engineering problems to resist oblique loads, most relevant being in
transmission towers and in rocks and dams for structural strengthening. In the present study, the breakout resistance of the
inclined anchors in sand has been worked out using limit equilibrium approach. The breakout resistance has been calculated
for different soil friction angles with varying relative depth ratio and anchor inclination. The break out factor increases
continuously with the inclination of the anchor. A comparison of predicted values of break out resistance of anchors by the
proposed analysis with the experimental values as reported by the other researchers showed reasonably good agreement. 相似文献
90.
四川盆地紫色丘陵区的水土保持林低效化问题已较严重。研究了其土壤方面的成因。通过对土壤构造、土壤肥力特性、土壤结构性评价等研究,指出该区人工林地的土壤构造发育不正常,土壤腐殖质胶体积累量低。土壤结构质量差等林地土壤退化是土壤水土保持功能降低的主要原因。根据研究的初步结果,提出了相应的对策建议。 相似文献