College;
of;
Life;
Sciences,;
Nankai;
University,;
Tianjin;
300071;
(China);
Research;
Institute;
of;
Elemento-Organic;
Chemistry,;
Nankai;
University,;
Tianjin;
300071;
(China);
Department;
of;
Biology,;
Pennsylvania;
State;
University,;
Pennsylvania;
16802;
(USA);
土壤有机质; 脱氢酶活性; 成土过程; 碳酸盐岩; 植物群落; 有机质含量; 风化; 碳酸钙;