喀斯特石漠化土壤结皮层藓类植物水分动力学特性

摘要

为探索土壤生物结皮在喀斯特石漠化生态恢复和治理中的生态作用，采用野外调查并结合室内测定植物吸水、脱水的实验方法，比较研究了土壤结皮层3种优势的藓类植物（长尖扭口藓Barbuladitrichoides、毛尖青藓Brachytheci⁃umpiligerum和狭网真藓Bryumalgovicum）对干旱环境的适应性。结果发现：土壤结皮中狭网真藓比另外两种藓类具有更高的最大持水率和吸水速率，吸水速率可达8.27 g·g-1干重/min；三种藓类的抗失水能力都较强。因此，土壤结皮藓类植物能以独特的水分吸收和利用方式适应喀斯特石漠化的恶劣环境，是环境恢复的重要先锋植物。%To explore the ecological restoration roles of soil biotic crusts in karst rocky desertification area, a field investigation was conducted and water absorption and dehydration of plants were measured in laboratory. We compared plant adaptability to dry habitat among Barbuladitrichoides, Brachytheciumpiligerumand Bryumalgovi⁃cumfrom soil crusts. The results revealed that the highest specific retention and water uptake rate were higher in B. algovicum than in the other mosses, and the water uptake rate of B. algovicum was up to 8.27 g · g-1 dry weight/min. However, these mosses were strong capacity to resist water loss. Therefore, the mosses in soil biotic crusts can act as the pioneer plants which are highly adaptable to severe environment on karst rocky desertifica⁃tion area through their unique way of water uptake and utilization.