中文摘要：

为了探讨喀斯特地区常见蕨类植物种对石灰土高钙环境的适应方式，以茂兰国家级自然保护区及其附近区域的11种常见蕨类植物为研究对象，通过对比其根际土及植株钙素的含量特征，分析了这11种植物对土壤钙素的吸收情况，以及钙素在植株各器官问的运转和分配情况。研究显示，在酸性土区，肾蕨（Nephrolepis auriculata）根际土的钙有效度显著高于其他10种蕨类植物；受酸性土钙含量低的影响，厌钙植物种的植株钙含量显著低于专性钙生植物种：除肾蕨和金星蕨（Parathe—lypteris glanduligera）Pb，酸性土区各植物种的植株各器官中钙含量为成熟叶〉根〉幼叶，石灰土区植株各器官的钙含量为根〉成熟叶〉幼叶，广布种凤尾蕨（Pteris creticavat．nervosa）的植株器官钙含量特征在石灰土和酸性土间存在差异：各专性钙生植物种的植株钙含量有显著的种间差异。以上结果表明，（1）肾蕨可通过富集、活化根际土钙素的方式来满足自身的需求；（2）土壤供钙条件会影响植株钙含量，且在不同土壤钙环境下，植株各器官钙含量特征的差异与其对土壤钙含量变化的适应行为有关；（3）5种专性钙生植物种对钙素的需求有差异，且其面对高钙环境起主导作用的适应方式也有所不同，柳叶蕨（Cyrtogonellum fraxinellum）、贯众（Cyrtomium fortune）、蜈蚣草（Pteris vittata）具有嗜钙或喜钙的特性，而铁线蕨（Adiantum capillus-veneris）属于低钙植物种。

英文摘要：

Aims Our objective was to analyze the calcium absorption and distribution characteristics of pteridophyte species, and to determine their adaptation to high calcium. Methods Eleven pteridophytes were collected from Maolan National Nature Reserve and the surrounding area. We analyzed their calcium absorption and distribution behavior by comparing the calcium content in each organ and the rhizosphere. Important findings In acidic soil, calcium availability in the rhizosphere of Nephrolepis auriculata was much higher than that of other species. Because of low calcium content in acidic soil, the calcium content of calcifuge was significantly lower than that of exclusive calciphytes. Except for N. auriculata and Parathelypteris glan- duligera, the calcium content in various organs of plants that lived in acidic soil were mature leaf 〉 roots 〉 young leaf, and the calcium content in various organs of plants that lived in calcareous soil were roots 〉 mature leaf 〉 young leaf. In addition, calcium content in various organs of Pteris cretica var. nervosa had differences between calcareous and acidic soils. Calcium content of exclusive calciphytes had significant interspecific differences. Results suggested that N. auriculata could meet its calcium needs by enriching and activating calcium in the rhizosphere. The calcium content in plants could be reflected by the calcium supply in the soil. In different soils, the calcium-content differences in various organs might be related to their adaptive behavior towards changes of soil calcium content. The demands for calcium of the five exclusive calciphytes species were disparate. When they encountered high calcium stress, their primary adaptation behaviors differed. Cyrtogonellum fraxinellum,Cyrtomium fortune and Pteris vittata had calciphilious features, but Adiantum capillus-veneris was a low calcium species.