The migration of elements among rock, soil and vegetation in karst area—A case in karst hilly area in Bama, Guangxi

Through the analysis on the elements relation ship and element removal between carbonate rocks and the soil, between carbonate rocks and vegetation (Alchornea trewioides and Callicarpa nudiflora Hook et Arn), and between soil and vegetation (Alchornea trewioides and Callicarpa nudiflora Hook et Arn). The study finds that, 1)there isa high correlativity between the rock and soil with the general removal sequenceas CaO＞MgO＞Na2O＞P2O5＞MnO＞Pb＞Zr＞Fe2O3＞TiO2＞SiO2＞Al2O3 from the rock to the soil; 2)there is also a high correlativity between the soil and the 2 species of tested plant, and the plants get similar element absorption coefficient from the soil, with the sequence of element absorption coefficient of the Alchornea trewioides being P＞Ca＞Fe＞K＞Na＞Mn＞Pb＞Al＞Mg＞Zr＞Ti＞SiO2, and that of the Callicarpa nudiflora Hook et Arn being P＞K＞Fe＞Na＞Ca＞Mn＞Al＞Pb＞Mg＞Zr＞Ti＞SiO2; Element migration follow certain rules. That is, rock elements are high correlated with soil elements. From rock to soil, the general element migration sequence is CaO＞MgO＞Na2O＞P2O5＞MnO＞Pb＞Zr＞Fe2O3＞TiO2＞SiO2＞Al2O3. 3)the macro-element implants are determined by the rock, so there is higher correlativity and consistency in the elemental composition of the plant growing under the same lithology.