基于时空不确定性分析的北京市农田土壤重金属镉含量等级划分
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摘要
为了从时空角度探讨耕地土壤环境质量的类别划分并为差别化利用和管理土地提供可参考信息,针对多年期采样数据,采用基于时空指示克里金的方法对北京市2013年农田土壤重金属镉含量进行等级划分。其中通过自适应方法确定了等级划分最适宜的概率阈值,并基于等级错划指数估计了等级划分的不确定性。结果表明:相较于基于时空普通克里金的方法,基于时空指示克里金方法划分的等级具有更高的准确率。2013年北京市镉含量等级为超过背景值的农田区域主要分布在昌平大部分地区、平谷中部地区、大兴南部地区、房山南部等靠近城镇中心的地带,等级为低于背景值的农田区域则主要分布在延庆西部地区、怀柔北部等远离城镇中心的地带。镉含量等级的错划指数分布反映了北京市农田土壤重金属镉含量等级划分的不确定性程度。等级划分的不确定性在一定程度上受点位分布及概率阈值的影响。基于时空指示克里金的等级划分方法可为开展耕地土壤环境质量类别划分工作提供辅助支撑。
For differential use and management of land, it is important to explore the category classification of farmland soil environmental quality from a spatio-temporal perspective. In this study, based on multi-year sample data, we used the spatio-temporal Indicator Krigingmethod to classify the grade of farmland soil heavy metal cadmium content in Beijing in 2013. The self-adaptive determination method wasadopted to determine the optimal probability threshold of grade classification, and a classification error index was utilized to evaluate gradeclassification uncertainty. The results showed that the method based on the spatio-temporal Indicator Kriging had better performance withhigher accuracy than the spatio-temporal Ordinary Kriging method. The regions where the cadmium content grade was higher than thebackground value were mainly located in most areas of Changping, the central area of Pinggu, and the southern area of Daxing, which areall near the urban center. In contrast, the regions where the cadmium content grade was lower than the background value were mainly locat?ed in the west part of Yanqing and the northern part of Huairou, which are at some distance from the urban center. The classification errorindex distribution reflected the uncertainty degree of the grade classification of soil cadmium content. The uncertainty is, to an extent, af?fected by the distribution of sample points and probability threshold. A grade classification method based on spatio-temporal Indicator Kriging can be used to support the classification of soil environmental quality categories.
For differential use and management of land, it is important to explore the category classification of farmland soil environmental quality from a spatio-temporal perspective. In this study, based on multi-year sample data, we used the spatio-temporal Indicator Krigingmethod to classify the grade of farmland soil heavy metal cadmium content in Beijing in 2013. The self-adaptive determination method wasadopted to determine the optimal probability threshold of grade classification, and a classification error index was utilized to evaluate gradeclassification uncertainty. The results showed that the method based on the spatio-temporal Indicator Kriging had better performance withhigher accuracy than the spatio-temporal Ordinary Kriging method. The regions where the cadmium content grade was higher than thebackground value were mainly located in most areas of Changping, the central area of Pinggu, and the southern area of Daxing, which areall near the urban center. In contrast, the regions where the cadmium content grade was lower than the background value were mainly locat?ed in the west part of Yanqing and the northern part of Huairou, which are at some distance from the urban center. The classification errorindex distribution reflected the uncertainty degree of the grade classification of soil cadmium content. The uncertainty is, to an extent, af?fected by the distribution of sample points and probability threshold. A grade classification method based on spatio-temporal Indicator Kriging can be used to support the classification of soil environmental quality categories.
引文
[1]中华人民共和国环境保护部.全国土壤污染状况调查公报[R].北京:中华人民共和国环境保护部,2014.The Ministry of Environmental Protection of the People′s Republic of China.Official journal of national survey on soil pollution[R].Beijing:The Ministry of Environmental Protection of PRC,2014.
[2]中华人民共和国环境保护部,中华人民共和国农业部.农用地土壤环境管理办法试行[R].北京:中华人民共和国环境保护部,中华人民共和国农业部,2017.The Ministry of Environmental Protection of the People′s Republic of China,Ministry of Agriculture of the People′s Republic of China.Methods of soil environmental management for agricultural land(Trial)[R].Beijing:The Ministry of Environmental Protection of PRC,Ministry of Agriculture of PRC,2017.
[3]中华人民共和国国务院.土壤污染防治行动计划[R].北京:中华人民共和国国务院,2016.The State Council of the People′s Republic of China.Action plan on soil pollution control[R].Beijing:The State Council of PRC,2016.
[4]中国国家环境保护局.土壤环境质量标准GB 15618-1995[S].北京:中国国家环境保护局,1995.National Environmental Protection Agency of the People′s Republic of China.Environmental quality standard for soils GB 15618-1995[S].Beijing:National Environmental Protection Agency of PRC,1995.
[5]中华人民共和国环境保护部.食用农产品产地环境质量评价标准HJ/T 332-2006[S].北京:中国环境科学出版社,2006.The Ministry of Environmental Protection of the People′s Republic of China.Standard of environmental quality assessment for edible agricultural products HJ/T 332-2006[S].Beijing:China Environmental Science Press.2006.
[6]李雪,李佳桐,孙宏飞,等.琼北农田土壤重金属水平及潜在生态风险[J].农业环境科学学报,2017,36(11):2248-2256.LI Xue,LI Jia-tong,SUN Hong-fei,et al.The levels and potential ecological risk of heavy metals in farmland soils in Northern Hainan Province,China[J].Journal of Agro-Environment Science,2017,36(11):2248-2256.
[7]蒋红群,王彬武,刘晓娜,等.北京市土壤重金属潜在风险预警管理研究[J].土壤学报,2015,52(4):731-746.JIANG Hong-qun,WANG Bin-wu,LIU Xiao-na,et al.Early warning of heavy metals potential risk governance in Beijing[J].Acta Pedologica Sinica,2015,52(4):731-746.
[8]陆安祥,孙江,王纪华,等.北京农田土壤重金属年际变化及其特征分析[J].中国农业科学,2011,44(18):3778-3789.LU An-xiang,SUN Jiang,WANG Ji-hua,el al.Annual variability and characteristics analysis of heavy metals in agricultural soil of Beijing[J].Science Agricultural Sinica,2011,44(18):3778-3789.
[9]孙江,张国光,董文光,等.北京市农田土壤重金属年际差异分析与评价[J].农业环境科学学报,2011,30(5):899-903.SUN Jiang,ZHANG Guo-guang,DONG Wen-guang,et al.Annual variability analysis and evaluation of heavy metals in Beijing agricultural soil,China[J].Journal of Agro-Environment Science,2011,30(5):899-903.
[10]霍霄妮,李红,张微微,等.北京耕作土壤重金属多尺度空间结构[J].农业工程学报,2009,25(3):223-229.HUO Xiao-ni,LI Hong,ZHANG Wei-wei,et al.Multi-scale spatial structure of heavy metals in Beijing cultivated soils[J].Transactions of the CSAE,2009,25(3):223-229.
[11]Najafian A,Dayani M,Motaghian H R,et al.Geostatistical assessment of the spatial distribution of some chemical properties in calcareous soils[J].Journal of Integrative Agriculture,2012,11(10):1729-1737.
[12]Goovaerts P.Geostatistics for natural resources evaluation[M].New York:Oxford University Press,1997.
[13]Isaaks E H,Srivastava R M.An introduction to applied geostatistics[M].New York:Oxford University Press,1989.
[14]Antunes I M H R,Albuquerque M T D.Using Indicator Kriging for the evaluation of arsenic potential contamination in an abandoned mining area(Portugal)[J].Science of the Total Environment,2013,442(15):545-552.
[15]Gao B B,Liu Y,Pan Y C,et al.Error index for additional sampling to map soil contaminant grades[J].Ecological Indicators,2017,77:129-138.
[16]Gao B B,Lu A X,Pan Y C,et al.Additional sampling layout optimization method for environmental quality grade classifications of farmland soil[J].IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing,2017,10(12):5350-5358.
[17]王彬武,李红,蒋红群,等.北京市耕地土壤重金属时空变化特征初步研究[J].农业环境科学学报,2014,33(7):1335-1344.WANG Bin-wu,LI Hong,JIANG Hong-qun,et al.Spatial-temporal variation of soil heavy metals in agricultural land in Beijing,China[J].Journal of Agro-Environment Science,2014,33(7):1335-1344.
[18]安婧,宫晓双,陈宏伟,等.沈抚灌区农田土壤重金属污染时空变化特征及生态健康风险评价[J].农业环境科学学报,2016,35(1):37-44.AN Jing,GONG Xiao-shuang,CHEN Hong-wei,et al.Temporal and spatial characteristics and health risk assessments of heavy metal pollution in soils of Shenfu irrigation area[J].Journal of Agro-Environment Science,2016,35(1):37-44.
[19]张静,邹滨,陈思萱,等.土壤重金属污染风险时空变化模拟与分析[J].测绘科学,2016,41(10):88-92.ZHANG Jing,ZOU Bin,CHEN Si-xuan,et al.Spatial-temporal simulation and analysis of health risks of heavy metal contaminated soil[J].Science of Surveying and Mapping,2016,41(10):88-92.
[20]杨勇,梅杨,张楚天,等.基于时空克里格的土壤重金属时空建模与预测[J].农业工程学报,2014,30(21):249-255.YANG Yong,MEI Yang,ZHANG Chu-tian,et al.Spatio-temporal modeling and prediction of soil heavy metal based on spatio-temporal Kriging[J].Transactions of the CSAE,2014,30(21):249-255.
[21]宋波,杨子杰,张云霞,等.广西西江流域土壤镉含量特征及风险评估[J].环境科学,2018,39(4):1888-1900.SONG Bo,YANG Zi-jie,ZHANG Yun-xia,et al.Accumulation of Cd and its risks in the soils of the Xijiang River drainage basin in Guangxi[J].Environmental Science,2018,39(4):1888-1900.
[22]姜菲菲,孙丹峰,李红,等.北京市农业土壤重金属污染环境风险等级评价[J].农业工程学报,2011,27(8):330-337.JIANG Fei-fei,SUN Dan-feng,LI Hong,et al.Risk grade assessment for farmland pollution of heavy metals in Beijing[J].Transactions of the CSAE,2011,27(8):330-337.
[23]尹国庆,江宏,王强,等.安徽省典型区农用地土壤重金属污染成因及特征分析[J].农业环境科学学报,2018,37(1):96-104.YIN Guo-qing,JIANG Hong,WANG Qiang,et al.Analysis of the sources and characteristics of heavy metals in farmland soil from a typical district in Anhui Province[J].Journal of Agro-Environment Science,2018,37(1):96-104.
[24]肖斌,赵鹏大,侯景儒.时空域中的指示克立格理论研究[J].地质与勘探,1999,35(4):25-28.XIAO Bin,ZHAO Peng-da,HOU Jing-ru.The theory of indicator Kriging study in temporal-spatial domain[J].Geology and Prospecting,1999,35(4):25-28.
[25]Christakos G.Random field models in earth sciences[M].San Diego:Academic Press,1992.
[26]Ma C S.Families of spatio-temporal stationary covariance models[J].Journal of Statistical Planning and Inference,2003,116(2):489-501.
[27]Dimitrakopoulos R,Luo X.Geostatistics for the next century[M].Netherlands:Kluwer Academic Publishers,1994:88-93.
[28]Myers D E,Journel A.Variograms with zonal anisotropies and noninvertible kriging systems[J].Mathematical Geology,1990,22(7):779-785.
[29]Cressie N,Huang H C.Classes of nonseparable,spatio-temporal stationary covariance functions[J].Journal of the American Statistical Association,1999,94(448):1330-1340.
[30]Iaco S D,Myers D E,Posa D.Space-time analysis using a general product-sum model[J].Statistics&Probability Letters,2001,52(1):21-28.
[31]Iaco S D,Myers D E,Posa D.Nonseparable space-time covariance models:Some parametric families[J].Mathematical Geology,2002,34(1):23-42.
[32]Bhunia G S,Kesari S,Chatterjee N,et al.Spatial and temporal variation and hotspot detection of kala-azar disease in Vaishali district(Bihar),India[J].BMC Infectious Disease,2013,13(1):64.
[33]Heuvlink G B M,Griffith D A.Space-time geostatistics for geography:A case study of radiation monitoring across parts of Germany[J].Geographical Analysis,2010,42(2):161-179.
[34]Zafra M S,Rado M B,Tobíasat A,et al.Space-time interpolation of daily air temperatures[J].Journal of Environmental Statistics,2012,3(5):1-15.
[35]李莎,舒红,徐正全.利用时空Kriging进行气温插值研究[J].武汉大学学报(信息科学版),2012,37(2):237-241.LI Sha,SHU Hong,XU Zheng-quan.Interpolation of temperature based on spatial-temporal Kriging[J].Geomatics and Information Science of Wuhan University,2012,37(2):237-241.
[36]Griffith D A,Heuvelink G B M.Deriving space-time variograms from space-time autogressive(STAR)model specifications[M]//Griffith DA,Heuvelink G B,Anthony G O,et al.Advances in spatial data handling and GIS:The 14th international symposium on spatial data handling.Berlin:Springer-Verlag,2012,38:3-12.
[37]高秉博.时空非平稳区域多目标抽样优化方法[D].北京:中国科学院大学,2015.GAO Bing-bo,Multi-targets sampling optimizaiton method for a spatio-temporal non-stationary region[D].Beijing:The University of Chinese Academy of Sciences,2015.
[38]Bilonick R A.Monthly hydrogen ion deposition maps for the northeastern U.S from July 1982 to September 1984[J].Atmospheric Environment,1988,22(9):1909-1924.
[39]Juang K W,Liao W J,Liu T L,et al.Additional sampling based on regulation threshold and kriging variance to reduce the probability of false delineation in a contaminated site[J].Science of the Total Environment,2008,389(1):20-28.
[40]陈同斌,郑袁明,陈煌,等.北京市土壤重金属含量背景值的系统研究[J].环境科学,2004,25(1):117-122.CHEN Tong-bin,ZHENG Yuan-ming,CHEN Huang,et al.Background concentrations of soil heavy metals in Beijing[J].Environmental Science,2004,25(1):117-122.
[41]Luo L,Ma Y B,Zhang S Z.An inventory of trace element inputs to agricultural soils in China[J].Journal of Environmental Management,2009,90(8):2524-2530.
[42]成世才,王兵,郭加朋,等.山东省鱼台水稻生产基地土壤镉分布现状及来源分析研究[J].科技情报开发与经济,2009,19(31):130-133.CHENG Shi-cai,WANG Bing,GUO Jia-peng,et al.Soil Cd current distribution and origin study of Yutai rice production base[J].SCI-Tech Information Development&Economy,2009,19(31):130-133.
[43]霍霄妮,李红,孙丹峰,等.北京耕地土壤重金属空间自回归模型及影响因素[J].农业工程学报,2010,26(5):78-82.HUO Xiao-ni,LI Hong,SUN Dan-feng,et al.Spatial autogression model for heavy metals in cultivated soils of Beijing[J].Transactions of the CSAE,2010,26(5):78-82.
[2]中华人民共和国环境保护部,中华人民共和国农业部.农用地土壤环境管理办法试行[R].北京:中华人民共和国环境保护部,中华人民共和国农业部,2017.The Ministry of Environmental Protection of the People′s Republic of China,Ministry of Agriculture of the People′s Republic of China.Methods of soil environmental management for agricultural land(Trial)[R].Beijing:The Ministry of Environmental Protection of PRC,Ministry of Agriculture of PRC,2017.
[3]中华人民共和国国务院.土壤污染防治行动计划[R].北京:中华人民共和国国务院,2016.The State Council of the People′s Republic of China.Action plan on soil pollution control[R].Beijing:The State Council of PRC,2016.
[4]中国国家环境保护局.土壤环境质量标准GB 15618-1995[S].北京:中国国家环境保护局,1995.National Environmental Protection Agency of the People′s Republic of China.Environmental quality standard for soils GB 15618-1995[S].Beijing:National Environmental Protection Agency of PRC,1995.
[5]中华人民共和国环境保护部.食用农产品产地环境质量评价标准HJ/T 332-2006[S].北京:中国环境科学出版社,2006.The Ministry of Environmental Protection of the People′s Republic of China.Standard of environmental quality assessment for edible agricultural products HJ/T 332-2006[S].Beijing:China Environmental Science Press.2006.
[6]李雪,李佳桐,孙宏飞,等.琼北农田土壤重金属水平及潜在生态风险[J].农业环境科学学报,2017,36(11):2248-2256.LI Xue,LI Jia-tong,SUN Hong-fei,et al.The levels and potential ecological risk of heavy metals in farmland soils in Northern Hainan Province,China[J].Journal of Agro-Environment Science,2017,36(11):2248-2256.
[7]蒋红群,王彬武,刘晓娜,等.北京市土壤重金属潜在风险预警管理研究[J].土壤学报,2015,52(4):731-746.JIANG Hong-qun,WANG Bin-wu,LIU Xiao-na,et al.Early warning of heavy metals potential risk governance in Beijing[J].Acta Pedologica Sinica,2015,52(4):731-746.
[8]陆安祥,孙江,王纪华,等.北京农田土壤重金属年际变化及其特征分析[J].中国农业科学,2011,44(18):3778-3789.LU An-xiang,SUN Jiang,WANG Ji-hua,el al.Annual variability and characteristics analysis of heavy metals in agricultural soil of Beijing[J].Science Agricultural Sinica,2011,44(18):3778-3789.
[9]孙江,张国光,董文光,等.北京市农田土壤重金属年际差异分析与评价[J].农业环境科学学报,2011,30(5):899-903.SUN Jiang,ZHANG Guo-guang,DONG Wen-guang,et al.Annual variability analysis and evaluation of heavy metals in Beijing agricultural soil,China[J].Journal of Agro-Environment Science,2011,30(5):899-903.
[10]霍霄妮,李红,张微微,等.北京耕作土壤重金属多尺度空间结构[J].农业工程学报,2009,25(3):223-229.HUO Xiao-ni,LI Hong,ZHANG Wei-wei,et al.Multi-scale spatial structure of heavy metals in Beijing cultivated soils[J].Transactions of the CSAE,2009,25(3):223-229.
[11]Najafian A,Dayani M,Motaghian H R,et al.Geostatistical assessment of the spatial distribution of some chemical properties in calcareous soils[J].Journal of Integrative Agriculture,2012,11(10):1729-1737.
[12]Goovaerts P.Geostatistics for natural resources evaluation[M].New York:Oxford University Press,1997.
[13]Isaaks E H,Srivastava R M.An introduction to applied geostatistics[M].New York:Oxford University Press,1989.
[14]Antunes I M H R,Albuquerque M T D.Using Indicator Kriging for the evaluation of arsenic potential contamination in an abandoned mining area(Portugal)[J].Science of the Total Environment,2013,442(15):545-552.
[15]Gao B B,Liu Y,Pan Y C,et al.Error index for additional sampling to map soil contaminant grades[J].Ecological Indicators,2017,77:129-138.
[16]Gao B B,Lu A X,Pan Y C,et al.Additional sampling layout optimization method for environmental quality grade classifications of farmland soil[J].IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing,2017,10(12):5350-5358.
[17]王彬武,李红,蒋红群,等.北京市耕地土壤重金属时空变化特征初步研究[J].农业环境科学学报,2014,33(7):1335-1344.WANG Bin-wu,LI Hong,JIANG Hong-qun,et al.Spatial-temporal variation of soil heavy metals in agricultural land in Beijing,China[J].Journal of Agro-Environment Science,2014,33(7):1335-1344.
[18]安婧,宫晓双,陈宏伟,等.沈抚灌区农田土壤重金属污染时空变化特征及生态健康风险评价[J].农业环境科学学报,2016,35(1):37-44.AN Jing,GONG Xiao-shuang,CHEN Hong-wei,et al.Temporal and spatial characteristics and health risk assessments of heavy metal pollution in soils of Shenfu irrigation area[J].Journal of Agro-Environment Science,2016,35(1):37-44.
[19]张静,邹滨,陈思萱,等.土壤重金属污染风险时空变化模拟与分析[J].测绘科学,2016,41(10):88-92.ZHANG Jing,ZOU Bin,CHEN Si-xuan,et al.Spatial-temporal simulation and analysis of health risks of heavy metal contaminated soil[J].Science of Surveying and Mapping,2016,41(10):88-92.
[20]杨勇,梅杨,张楚天,等.基于时空克里格的土壤重金属时空建模与预测[J].农业工程学报,2014,30(21):249-255.YANG Yong,MEI Yang,ZHANG Chu-tian,et al.Spatio-temporal modeling and prediction of soil heavy metal based on spatio-temporal Kriging[J].Transactions of the CSAE,2014,30(21):249-255.
[21]宋波,杨子杰,张云霞,等.广西西江流域土壤镉含量特征及风险评估[J].环境科学,2018,39(4):1888-1900.SONG Bo,YANG Zi-jie,ZHANG Yun-xia,et al.Accumulation of Cd and its risks in the soils of the Xijiang River drainage basin in Guangxi[J].Environmental Science,2018,39(4):1888-1900.
[22]姜菲菲,孙丹峰,李红,等.北京市农业土壤重金属污染环境风险等级评价[J].农业工程学报,2011,27(8):330-337.JIANG Fei-fei,SUN Dan-feng,LI Hong,et al.Risk grade assessment for farmland pollution of heavy metals in Beijing[J].Transactions of the CSAE,2011,27(8):330-337.
[23]尹国庆,江宏,王强,等.安徽省典型区农用地土壤重金属污染成因及特征分析[J].农业环境科学学报,2018,37(1):96-104.YIN Guo-qing,JIANG Hong,WANG Qiang,et al.Analysis of the sources and characteristics of heavy metals in farmland soil from a typical district in Anhui Province[J].Journal of Agro-Environment Science,2018,37(1):96-104.
[24]肖斌,赵鹏大,侯景儒.时空域中的指示克立格理论研究[J].地质与勘探,1999,35(4):25-28.XIAO Bin,ZHAO Peng-da,HOU Jing-ru.The theory of indicator Kriging study in temporal-spatial domain[J].Geology and Prospecting,1999,35(4):25-28.
[25]Christakos G.Random field models in earth sciences[M].San Diego:Academic Press,1992.
[26]Ma C S.Families of spatio-temporal stationary covariance models[J].Journal of Statistical Planning and Inference,2003,116(2):489-501.
[27]Dimitrakopoulos R,Luo X.Geostatistics for the next century[M].Netherlands:Kluwer Academic Publishers,1994:88-93.
[28]Myers D E,Journel A.Variograms with zonal anisotropies and noninvertible kriging systems[J].Mathematical Geology,1990,22(7):779-785.
[29]Cressie N,Huang H C.Classes of nonseparable,spatio-temporal stationary covariance functions[J].Journal of the American Statistical Association,1999,94(448):1330-1340.
[30]Iaco S D,Myers D E,Posa D.Space-time analysis using a general product-sum model[J].Statistics&Probability Letters,2001,52(1):21-28.
[31]Iaco S D,Myers D E,Posa D.Nonseparable space-time covariance models:Some parametric families[J].Mathematical Geology,2002,34(1):23-42.
[32]Bhunia G S,Kesari S,Chatterjee N,et al.Spatial and temporal variation and hotspot detection of kala-azar disease in Vaishali district(Bihar),India[J].BMC Infectious Disease,2013,13(1):64.
[33]Heuvlink G B M,Griffith D A.Space-time geostatistics for geography:A case study of radiation monitoring across parts of Germany[J].Geographical Analysis,2010,42(2):161-179.
[34]Zafra M S,Rado M B,Tobíasat A,et al.Space-time interpolation of daily air temperatures[J].Journal of Environmental Statistics,2012,3(5):1-15.
[35]李莎,舒红,徐正全.利用时空Kriging进行气温插值研究[J].武汉大学学报(信息科学版),2012,37(2):237-241.LI Sha,SHU Hong,XU Zheng-quan.Interpolation of temperature based on spatial-temporal Kriging[J].Geomatics and Information Science of Wuhan University,2012,37(2):237-241.
[36]Griffith D A,Heuvelink G B M.Deriving space-time variograms from space-time autogressive(STAR)model specifications[M]//Griffith DA,Heuvelink G B,Anthony G O,et al.Advances in spatial data handling and GIS:The 14th international symposium on spatial data handling.Berlin:Springer-Verlag,2012,38:3-12.
[37]高秉博.时空非平稳区域多目标抽样优化方法[D].北京:中国科学院大学,2015.GAO Bing-bo,Multi-targets sampling optimizaiton method for a spatio-temporal non-stationary region[D].Beijing:The University of Chinese Academy of Sciences,2015.
[38]Bilonick R A.Monthly hydrogen ion deposition maps for the northeastern U.S from July 1982 to September 1984[J].Atmospheric Environment,1988,22(9):1909-1924.
[39]Juang K W,Liao W J,Liu T L,et al.Additional sampling based on regulation threshold and kriging variance to reduce the probability of false delineation in a contaminated site[J].Science of the Total Environment,2008,389(1):20-28.
[40]陈同斌,郑袁明,陈煌,等.北京市土壤重金属含量背景值的系统研究[J].环境科学,2004,25(1):117-122.CHEN Tong-bin,ZHENG Yuan-ming,CHEN Huang,et al.Background concentrations of soil heavy metals in Beijing[J].Environmental Science,2004,25(1):117-122.
[41]Luo L,Ma Y B,Zhang S Z.An inventory of trace element inputs to agricultural soils in China[J].Journal of Environmental Management,2009,90(8):2524-2530.
[42]成世才,王兵,郭加朋,等.山东省鱼台水稻生产基地土壤镉分布现状及来源分析研究[J].科技情报开发与经济,2009,19(31):130-133.CHENG Shi-cai,WANG Bing,GUO Jia-peng,et al.Soil Cd current distribution and origin study of Yutai rice production base[J].SCI-Tech Information Development&Economy,2009,19(31):130-133.
[43]霍霄妮,李红,孙丹峰,等.北京耕地土壤重金属空间自回归模型及影响因素[J].农业工程学报,2010,26(5):78-82.HUO Xiao-ni,LI Hong,SUN Dan-feng,et al.Spatial autogression model for heavy metals in cultivated soils of Beijing[J].Transactions of the CSAE,2010,26(5):78-82.