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Pedosphere 2003年第3期13卷 193-198页

作者： SHI ZHOU, HUANG MINGXIANG and LI YANInstitute of Agricultural Remote Sensing and Information System, Zhejiang University, Hangzhou 310029 (China) Institute of Agricultural Remote Sensing and Information System Zhejiang University Hanyzhou 310029

45 and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984respectively, in Shangyu of Zhejiang Province, China, to investigate the physico-chemicalproperties and the hyperspectral characteristics of the saline soils and to make an assessment ontheir relationships. The reflectance spectra of saline soils were measured using a spectroradiometerin laboratory. The mean spectral curves of the saline soils from the two sites different inreclamation year showed that the saline soil taken from the recently reclaimed land with highersalinity demonstrated a lower reflectance intensity in the spectral region from about 550 nm to 2300nm. In addition, nine absorption bands, i.e., 488 nm, 530 nm, 670 nm, 880 nm, 940 nm, 1400 nm, 1900nm, 2 200 nm and 2 300 nm, were chosen as the spectral bands to investigate the relationshipsbetween soil physico-chemical properties by means of Pearson correlation analysis. Finally, thefirst two principal components were calculated from nine absorption bands and used to discriminatethe saline soil samples taken from two sampled fields. The results indicate that it is feasible todetect physico-chemical properties of saline soils from fields reclaimed for varying time periods onthe basis of the hyperspectral data.

关键词： coast hyperspectral reclamation saline soils

Salic Horizons in soils of the USA

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Pedosphere 2013年第5期23卷 600-608页

作者： J. G. BOCKHEIM A. E. HARTEMINK Department of Soil Science University of Wisconsin

The taxonomic hierarchy and nationwide distribution of soils with a salic horizon were studied using the USA Natural Resources Conservation Service Soil Survey Geographic （SSURGO） Database to provide a more holistic view of the role of soil-forming factors in pedogenesis than from isolated case studies. soils with a salic horizon occupied an area of 11 000 km2, i.e., 0.1% of land area in the contiguous USA. These soils occur narrowly in three great groups （Aquisalids, Haplosalids and Halaquepts）, 11 subgroups, and 97 soil series. soils with a salic horizon commonly had a mesic （50% of soil series） or thermic （19%） soil-temperature class, an aquic （89%） soil-moisture class, a mixed mineral class （79%）, a calcareous （52%） reaction class, a superaztive （59%） cation exchange activity class, and a fine （24% of soil series）, fine-loamy （24% of soil series）, or fine-silty （19% of soil series） particle-size class. soils with a salic horizon were concentrated in the Basin and Range Province of western USA. The key pedogenic processes leading to the development of salic horizons were salinization, gleization, and calcification, with some evidence for argilluviation and silicification.

关键词： saline soils soil classification solonchak

The effect of seismic action on stability of saline soil subgrade in cold region based on isothermal stratification method

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Earthquake Research Advances 2024年第3期4卷 66-81页

作者： Jie Cheng Yu Zhang Ying Ma Xuerui Chen Ning An School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou730070China Key Laboratory of Railway Industry of Plateau Railway Transportation Intelligent Management and Control Lanzhou Jiaotong UniversityLanzhou730070China Gansu Institute of Engineering Geology Lanzhou730030China

With the change of seasons, the shear strength of saline soil subgrade filler will change with the change of external temperature, which will aggravate the adverse effects of seismic on the subgrade. To explore the influence of seismic action on the stability of saline soil subgrade under the influence of temperature on the strength of saline soil subgrade filler, this paper first carried out saline soil shear tests at different temperatures to obtain the influence of temperature on the shear strength of saline soil. Then, the temperature field of the saline soil subgrade was simulated, and then based on the subgrade isothermal stratification model and FLAC3D, the displacement and acceleration amplification effects of seismic action on the shady slope, sunny slope and subgrade of saline soil subgrade in different months were analyzed. The following conclusions were finally drawn: under the action of seismic, In the process of the change of subgrade temperature of Qarhan-Golmud Expressway between 7.7°C and 27°C, the change of saline soil cohesion is the main factor affecting the stability of subgrade slope, and the maximum and minimum values of subgrade surface settlement appear in September and June of each year,respectively. In August, the differences of settlement between the shady slope and the sunny slope shoulder of the subgrade were the largest, and the acceleration of the shady slope and the sunny slope and the inside of the subgrade changed most significantly in the vertical direction. Special attention should be paid to the seismic early warning in the above key months;In the range from both sides of the shoulder to the centerline of the roadbed,the acceleration amplification effect starts to increase significantly from about 3m from the centerline of the roadbed to the centerline, so it is necessary to pay attention to the seismic design of this range.

关键词： Subgrade stability saline soils Acceleration amplification effect Seismic design

Application of dynamic compaction and rolling compaction in the subgrade improvement of Qarhan-Golmud Highway

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Research in Cold and Arid Regions 2013年第5期5卷 603-607页

作者： Yu Zhang JianKun Liu JianHong Fang AnHua Xu Lanzhou Jiaotong University Beijing Jiaotong University Qinghai Research Institute of Transportation

Melt shrinkage, salt bulge, and corrosiveness are common problems with saline soils, which damage highway foundations and cause huge financial losses. In order to improve the saline soil subgrade, dynamic compaction （DC） and rolling compaction （RC） technology were applied on the Qarhan-Golmud Highway in Qinghai Province, China. A field experi- ment was conducted in which shear strength, deformation modulus, and the working mechanism of the composite foun- dation were analyzed after reinforcement. Both the DC and RC methods were found to be effective and helped to improve the foundation strength of saline soils, although the ultimate bearing capacity and deformation modulus of the RC method were lower than that of the DC method.

关键词： dynamic compaction rolling compaction saline soils reinforcement effects

Reinforcement effects of ground treatment with dynamic compaction replacement in cold and saline soil regions

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Research in Cold and Arid Regions 2013年第4期5卷 440-443页

作者： Yu Zhang JianKun Liu JianHong Fang AnHua Xu Lanzhou Jiaotong University Beijing Jiaotong University Qinghai Research Institute of Transportation

The mechanical property of saline soils varies with moisture and climate in the cold and salt lake region of Qinghai-Tibet Plateau, which influences project construction. In order to improve foundation reinforcement effect of the QarharvaTrolmud Highway, Qinghai Province, China, dynamic compaction replacement （DCR） composite foundation was applied in saline soils. A field experiment was conducted in this area, where strength and working mechanism of pier-soil and deformation modulus of the composite foundation was analyzed after reinforcement. This paper presents methods for determining the coefficient on the bearing capacity evaluation and deformation modulus of composite foundation with DC1L Reinforcement case of DCR is highly effective in saline soils of the salt lake regions, which helps the mi-tion of water and salt in saline soils.

关键词： dynamic compaction replacement saline soils reinforcement effects

Mitigation Rice Yield Scaled Methane Emission and Soil Salinity Stress with Feasible Soil Amendments

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Journal of Agricultural Chemistry and Environment 2021年第1期10卷 16-36页

作者： Laila Khatun Muhammad Aslam Ali Mahmud Hossain Sumon Md. Bazlul Islam Fahima Khatun Department of Environmental Science Bangladesh Agricultural University Mymensingh Bangladesh Department of Soil Science Bangladesh Agricultural University Mymensingh Bangladesh Department of Seed Science and Technology Bangladesh Agricultural University Mymensingh Bangladesh Department of Pathobiology Bangabandhu Sheikh Mujibur Rahman Agricultural University Gazipur Bangladesh

Sea level rise and saline water intrusion have been affecting land use and crop production especially rice in the coastal areas of major rice growing countries including Bangladesh. The upward trend in salinity intrusion has been hampering crop production, particularly rice cultivation in the coastal areas of Bangladesh. Therefore, an experiment was conducted on rice planted saline soils under the Nethouse at Bangladesh Agricultural University, Mymensingh to improve the properties of salt affected soils for rice cultivation as well as controlling methane (CH4) emissions with feasible soil organic amendments and recommended inorganic fertilizers. The experimental treatments were arranged under 25 mM NaCl, 50 mM NaCl and 75 mM NaCl salinity levels with different combinations of NPKSZn, biochar, phosphogypsum and Trichocompost. It was found that CH4 emission rates were suppressed with phospho-gypsum and biochar amendments within the salinity level 25 mM to 50 mM, beyond this salinity level (at 75 mM), soil amendments were not effective to control CH4 emissions. From panicle initiation to grain ripening stages treatment T4 (100% NPKSZn + 75 mM NaCl stress) showed the highest CH4 emission rate, while lower CH4 emission rate was recorded in T5 (100% NPKSZn + 25 mM NaCl stress + Phospho-gypsum) and T8 treatment (100% NPKSZn + 50 mM NaCl + Phospho-gypsum). In case of s

关键词： CH4 Rice saline soils Phosphogypsum Biochar Trichocompost