【作者】 沈灵； 柳云龙；

【Author】 Shen Ling;Liu Yunlong;Department of Geography,School of Environmental and Geographical Sciences,Shanghai Normal University;

【机构】 上海师范大学环境与地理科学学院地理系；

【摘要】 为探讨城市化过程中人为因素对城市土壤磁学特征的影响,将地统计学和分形理论相结合,以上海市徐汇区为研究区域,通过采集土壤样本,分析城市土壤磁性参数的空间变异特征。结果表明:徐汇区土壤磁性明显增强,以铁磁矿为主的亚铁磁性矿物是土壤磁性增强的贡献者,并存在少量不完整反铁磁性矿物,晶粒以假单畴PSD和多畴MD为主。半方差函数拟合分析结果表明,土壤低频磁化率(χ_lf)、饱和等温剩磁（SIRM）、硬剩磁（HIRM）的最优拟合模型为球状模型,S_-300mT的最优拟合模型为高斯模型,这4个磁学参数具有强烈的空间自相关性;分形学分析结果显示,土壤χ_lf、HIRM和S_-300mT的D值均>1.5,磁学参数局部空间分异特征具有随机性。采用普通克里金插值法绘制徐汇区土壤磁学参数空间分布图,χ_lf、SIRM、S_-300mT呈条带状分布,HIRM呈岛状分布,表现为徐汇区东北部为磁性高值区,由东北向西南呈降低趋势,反映了城市土壤磁性空间变异的复杂情况受到城市化、工业化、交通、设施等多种人为活动因素的影响。更多还原

【Abstract】 In order to explore the impact of human factors on the magnetic characteristics of urban soil in the process of urbanization,combined with geostatistics and fractal theory to analyze the spatial variability of urban soil magnetic parameters by collecting soil samples in Xuhui District of Shanghai.The results showed that the soil magnetism in Xuhui district was enhanced obviously,ferrimagnetic minerals,mainly ferromagnetic minerals,helped to enhance soil magnetic,and there were few antiferromagnetic minerals,the crystal grains were dominated by pseudo-single-domain and multi-domain,The semivariance function fitting analysis results showed thatχ_lf,SIRM,and HIRM could be best fitted with the spherical model,and S_-300mTcould be best fitted with the Gaussian model.These four magnetic parameters had strong spatial autocorrelation.The results of fractal analysis showed that the D values of soilχ_lf,HIRM and S_-300mTwere all greater than 1.5,and the local spatial differentiation of magnetic parameters was affected by random factors.Used ordinary kriging interpolation to draw the spatial distribution map of soil magnetic parameters in Xuhui District,χ_lf,SIRM,and S_-300mTwere distributed in strips,and HIRM was distributed in islands,which showed that the northeast part of Xuhui District was a high magnetic value area.There was a decreasing trend from northwest to southwest,reflected that the complex spatial variability of urban soil magnetism was affected by various human activities such as urbanization,industrialization,transportation,and facilities.更多还原