| The article are to recognize the level of metals content in vegetables and soils of Lanzhou city; to research vegetables'BCFs of metals; to exploring the relationships between soil properties and heavy metals accumulated in vegetable species; and to analyze the possible source of metals in vegetable land soil, to provide scientific data for the safety of vegetable production base environment, and corresponding control strategy of heavy metal contamination.Soil properties (pH and EC) and five metals' (Zn, Cd, Cr, Cu and Pb) contents in vegetable basses of Lanzhou city were determined. The studied soils were generally alkaline, with mean pH values of 8.35. The mean values of sol EC were 0.40 ds m-1. The mean value of content of all the metals (Zn, Cd, Cr, Cu and Pb) in soils of all the vegetable basses had not exceeded the gradeâ…¡of national standard, but Cu content of soil from Xigu and Cd content of all the eight districts had exceeded the grade I of national standard. The Zn content of soils from Chengguan and Dingyuan had exceeded the back ground value of Lanzhou, while soils from other districts had not. Cd, Cr, Cu, Pb content of soils from nearly all the districts had exceed the background value of soil elements of Lanzhou, except Cr content of soil from Chengguan (55.03 mg kg-1), and Cu content of soil from Huazhuang (22.69 mg kg-1).Soil properties and five metal contents in vegetable basses of Lanzhou city were determined. According to the Shapiro-wilk test for distribution types, all of the soil properties followed the normal distribution. The studied soils were generally alkaline, with mean pH values of 8.35. The mean values of sol EC were 0.40 ds m-1. Contents of the five metals we determined are according to some previous report.Some of the concentrations of Cu and Cd in soil samples exceed gradeâ… , none of the concentrations of the five metals had exceeded gradeâ…¡. This means that a large portion of the soil sample didn't exceed the safety standard.The differences among metals concentrations in soil from different districts were analyzed. The five metals'contents of soil samples from eight areas are determined. We observed that each of the four metals (Zn, Cd, Cr and Cu) expressed significant difference as soil samples from different districts. Zn contents in soil samples from Chengguan and Dingyuan were significantly higher, while samples from Anning, Heping and Huazhuang were lower. Cd contents of soil samples from Dingyuan were significantly higher, while samples from Huazhuang were significantly lower. The highest Cr contents were found in samples from Dingyuan, while the lowest were from Chengguan, besides these two areas, Cr contents of soil samples were statistically identical. Cu contents of soil samples from Xigu were similar to samples from Heping, but significantly higher than samples from other areas. Pb contents of soil samples from eight districts didn't expressed statistical difference.The values of pH of soil from the eight districts didn't express significant difference. The values of EC of soil from different areas showed significant difference, the EC of soil samples from Chengguan and Huazhuang were significantly higher than others.For Zn content, samples of Lactuca sativa from eight areas didn't express significant difference among its own samples, while the other five plants had; For Cd content, samples of Lactuca sativa, Cucumis sativus and Cucurbita maxima expressed significant difference among their own samples as from different districts; For Cr content, each of the six kinds of vegetable plants expressed significant difference among their own samples as from different districts; For Cu content, each kind of plants expressed significant difference among their own samples as from different districts; For Pb content, samples of Allium fistulosum from eight areas didn't express significant difference, while the other five had.For BCFs of Zn, Allium fistulosum, Cucumis sativus and Cucurbita maxima expressed significant difference among their own samples; For BCFs of Cd, Lactuca sativa and Brassica campestris expressed significant difference among their own samples; For BCFs of Cr, Brassica campestris, Allium fistulosum and Cucumis sativa expressed significant difference among their own samples; For BCFs of Cu, Allium tuberosum and Allium fistulosum expressed significant difference among their own samples; For BCFs of Pb, Allium fistulosum from eight areas didn't express significant difference for Pb content, while the other five plants had.Significant positive correlations were found between all the six kinds of vegetable plants and their soil samples, for heavy metals (Zn, Cd, Cr, Cu and Pb) content. Content of four metals (Cd, Cr, Cu and Pb) in all the vegetable plants we selected expressed negative correlations with pH and EC in their soil. Content of Zn in all the vegetable plants we selected expressed negative correlations with pH, however, all expressed positive with EC in their soil. Significant correlations were found between most of the samples and their soil properties.BCFs of Zn of all the six kinds of plants showed positive correlations with soil pH and EC, while they all expressed negative correlation with their soil Zn content; BCFs of Cd of all the six plants had positive correlations with soil pH, Nearly all the six plants had negative correlation with soil EC and soil Zn content; BCFs of Cr of most of the plants expressed positive correlations with soil pH, while most of the plants expressed negative correlations with their soil EC and soil Cr content; BCFs of Cu of most of the plants expressed positive correlations with soil pH, while most of the plants expressed negative correlations with their soil EC and soil Cu content; BCFs of Pb of most of the plants expressed positive correlations with soil pH, while most of the plants expressed negative correlations with their soil EC and soil Pb content. Correlations among soil properties were also been studied. Most of the soil samples'metals content expressed significant negative correlations with their pH and EC.We observed that Zn content of samples from Heping, Pingan and Huazhuang expressed significant difference among the six kinds of plants, Samples of Lactuca sativa and Cucumis sativus from often accumulated significantly higher level of Zn; we observed that Cd content of samples from Chengguan or Zhonghe expressed significant difference among the six kinds of plants, samples of Brassica campestris often accumulated significantly higher level of Cd, while Cucurbita maxima often accumulated lower level of Cd; We observed that Cr content of samples from six districts (Anning, Xigu, Chengguan, Heping, Dingyuan and Pingan) expressed significant difference among the six kinds of plants, samples of Brassica campestris often accumulated significantly higher level of Cr, while Allium tuberosum often accumulated lower level of Cr; we observed that Cu content of samples from Chengguan, Heping, Dingyuan and Huazhuang expressed significant difference among the six kinds of plants, Cu content in Lactuca sativa, Allium tuberosum and Cucumis sativus were often significantly higher, while Cu content in Allium fistulosum often lower; we observed that Pb content of samples from three districts (Heping, Pingan and Huazhuang) expressed significant difference among the six kinds of plants, while samples from other districts didn't, Three kinds of vegetable plants (Lactuca sativa, Brassica campestris and Cucumis sativus) often accumulated significantly higher level of Pb, while Allium fistulosum often accumulated lower.
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