CAO Jian-hua1,2,ZHU Min-jie1,HUANG Fen1,2,LU Qian1,2
1.Institute of Karst Geology,Chinese Academy of Geological Sciences,Key Laboratory of Karst Dynamics, Ministry of Land and Resources,Guilin,Guangxi 541004,China; 2.International Research Center on Karst under the Auspices of UNESCO,Guilin,Guangxi 541004,China
Abstract: The Maolan National Natural Reserve is a rare subtropical karst forest around the world. To clarify the different conditions of calcium forms in plant leaves under different geological backgrounds,a karst area of Banzhai Underground River catchment (limestone and dolomite) and non-karst areas of Yaopai catchment (sandstone or shale) in the natural reserve were selected for comparison study.13different plant species were collected from the study areas,6of them are endemic species for karst or non-karst areas.The total contents of calcium in leaf samples, the distribution of calcium in subcellular fractions,and the forms of calcium were analyzed.The results showed that 1) the average content of calcium in the plant leaves from the karst area was 1216.82mg/kg,which was 58.45%higher than that of leaves from the non-karst areas; 2)calcium pectate,which accounts for 27.91%— 32.82%of the total calcium in the leaves of calciphile plants,is the main form of calcium in the calciphile plant leaves in the karst area; whereas,calcium oxalate,which accounts for 33.69%—34.34%of the total calcium in the calcifuge plant leaves,is the main form of calcium in the calcifuge plant leaves in the non-karst areas;3)59.05%— 66.54%of the total calcium exists in cell-wall of calciphile plant leaves in the karst area,in contrast,36.67%— 43.77%of the total calcium exists in cytoplasm of the calcifuge plant leaves in non-karst area. The comparative research provided a new approach in better understanding of the karst ecosystem.
Key words: calcium;geological conditions;plant leaves;Maolan Karst Forest Natural Reserve
*Corresponding Author, E-Mail: jhcao@karst.edu.cn
Bulletin of Mineralogy, Petrology and Geochemistry Vol. 30, No.3, 2011, page 251-260
(Source from http://www.cnki.com.cn/)
