With the wetland landscape in New Coastal District of Tianjin City as the chief study objective and based on the remote sensing and non-remote sensing data of ETM/TM with 1999-2007 as the time scale and the new admini...With the wetland landscape in New Coastal District of Tianjin City as the chief study objective and based on the remote sensing and non-remote sensing data of ETM/TM with 1999-2007 as the time scale and the new administrative region of New Coastal District as the space (scale) scope, this paper conducted the study on the landscape pattern change. The results showed that the natural wetland and agricultural land tended to decrease, while the saltern, maricultural areas and construction land increased apparently. The overall landscape shape tended to develop in simplification and regulation and with the development of population and social economy, human’s intervention to the landscape was getting improved.展开更多
It is imperative to develop a risk assessment system for quickly predicting storm surge disaster due to the vulnerability of Tianjin Binhai New Area. The flood routing model with user-defined breaches was firstly esta...It is imperative to develop a risk assessment system for quickly predicting storm surge disaster due to the vulnerability of Tianjin Binhai New Area. The flood routing model with user-defined breaches was firstly estab- lished based on the seed spread algorithm in order to achieve a rapid forecasting of storm surge flood information. Furthermore, fuzzy mathematics was utilized to identify the storm disaster grade, and the hazard mapping was con- ducted to visually obtain the hazard spatial and temporal distribution. Finally, the flood routing visuaUzation method was proposed based on numerical simulation of storm surge to achieve the reappearance scene of dynamic evolution process. The developed system can play a vital role in the management and decision-making of sea dyke mitigation engineering in Tianjin Binhai New Area.展开更多
The Tianjin coastal area is a typical soft soil region,where the soil is a marine deposit of the late Quaternary.The soil dynamic parameters from seismic risk assessment reports are collected,and drilling of 15 holes ...The Tianjin coastal area is a typical soft soil region,where the soil is a marine deposit of the late Quaternary.The soil dynamic parameters from seismic risk assessment reports are collected,and drilling of 15 holes was carried out to sample the soils and measure their dynamic characteristics.The data was divided into 7 types based on lithology,namely,muddy clay,muddy silty clay,silt,silty clay,clay,silty sand and fine sand.Statistics of the dynamic parameters of these soils are collected to obtain the mean values of dynamic shear modulus ratio and damping ratio at different depths.Then,two typical drill holes are selected to establish the soil dynamic models to investigate the seismic response in different cases.The dynamic seismic responses of soil are calculated using the statistical values of this paper,and the values of Code(1994) and those recommended by Yuan Xiaoming et al.(2000),respectively.The applicability and pertinence of the statistical value obtained in this paper are demonstrated by the response spectrum shape,peak ground acceleration and response spectral characteristics.The results can be taken as a reference of the soil dynamic value in this area and can be used in the seismic risk assessment of engineering projects.展开更多
Based on the concept of ecosystem carrying capacity,the indicator system of quantitative assessment was set up,which consisted of support indicator system and pressure indicator system.And the factor analysis method w...Based on the concept of ecosystem carrying capacity,the indicator system of quantitative assessment was set up,which consisted of support indicator system and pressure indicator system.And the factor analysis method was used to screen the indicator system.Different from the traditional indicator weight determination based on the absolute values of the coefficients of regression equation,the squares of factor loadings in the rotated component matrix were attempted to determine the weights of 40 assessment indicators.The result shows that ecological support system and pressure system in Binhai New Area are relatively balanced among six years,and the developing level of urban ecosystem is basically healthy on the whole.However,due to continuously increasing pressure of the resources consumption caused by the rapid growth of the second industry,which is the Leading Industry of Binhai New Area,the ecosystem carrying capacity reached the minimum in 2005.展开更多
基金Supported by National Natural Sciences Foundation (30872039)Key Projects of Beijing Natural Sciences Foundation (09D0297)~~
文摘With the wetland landscape in New Coastal District of Tianjin City as the chief study objective and based on the remote sensing and non-remote sensing data of ETM/TM with 1999-2007 as the time scale and the new administrative region of New Coastal District as the space (scale) scope, this paper conducted the study on the landscape pattern change. The results showed that the natural wetland and agricultural land tended to decrease, while the saltern, maricultural areas and construction land increased apparently. The overall landscape shape tended to develop in simplification and regulation and with the development of population and social economy, human’s intervention to the landscape was getting improved.
基金Supported by the National Basic Research Program of China("973"Program2013CB035906)National Natural Science Foundation of China(No.51209159 and No.51439005)
文摘It is imperative to develop a risk assessment system for quickly predicting storm surge disaster due to the vulnerability of Tianjin Binhai New Area. The flood routing model with user-defined breaches was firstly estab- lished based on the seed spread algorithm in order to achieve a rapid forecasting of storm surge flood information. Furthermore, fuzzy mathematics was utilized to identify the storm disaster grade, and the hazard mapping was con- ducted to visually obtain the hazard spatial and temporal distribution. Finally, the flood routing visuaUzation method was proposed based on numerical simulation of storm surge to achieve the reappearance scene of dynamic evolution process. The developed system can play a vital role in the management and decision-making of sea dyke mitigation engineering in Tianjin Binhai New Area.
基金sponsored by the State-level Public Welfare Scientific Research Courtyard Basic Scientific Research ProgramInstitute of Crustal Dynamics+1 种基金CEA (ZDJ2009-07ZDJ2009-23)
文摘The Tianjin coastal area is a typical soft soil region,where the soil is a marine deposit of the late Quaternary.The soil dynamic parameters from seismic risk assessment reports are collected,and drilling of 15 holes was carried out to sample the soils and measure their dynamic characteristics.The data was divided into 7 types based on lithology,namely,muddy clay,muddy silty clay,silt,silty clay,clay,silty sand and fine sand.Statistics of the dynamic parameters of these soils are collected to obtain the mean values of dynamic shear modulus ratio and damping ratio at different depths.Then,two typical drill holes are selected to establish the soil dynamic models to investigate the seismic response in different cases.The dynamic seismic responses of soil are calculated using the statistical values of this paper,and the values of Code(1994) and those recommended by Yuan Xiaoming et al.(2000),respectively.The applicability and pertinence of the statistical value obtained in this paper are demonstrated by the response spectrum shape,peak ground acceleration and response spectral characteristics.The results can be taken as a reference of the soil dynamic value in this area and can be used in the seismic risk assessment of engineering projects.
文摘Based on the concept of ecosystem carrying capacity,the indicator system of quantitative assessment was set up,which consisted of support indicator system and pressure indicator system.And the factor analysis method was used to screen the indicator system.Different from the traditional indicator weight determination based on the absolute values of the coefficients of regression equation,the squares of factor loadings in the rotated component matrix were attempted to determine the weights of 40 assessment indicators.The result shows that ecological support system and pressure system in Binhai New Area are relatively balanced among six years,and the developing level of urban ecosystem is basically healthy on the whole.However,due to continuously increasing pressure of the resources consumption caused by the rapid growth of the second industry,which is the Leading Industry of Binhai New Area,the ecosystem carrying capacity reached the minimum in 2005.
