ECOPHYSIOLOGICAL PERFORMANCE OF THE AEROTERRESTRIAL GREEN ALGA KLEBSORMIDIUM CRENULATUM (CHAROPHYCEAE, STREPTOPHYTA) ISOLATED FROM AN ALPINE SOIL CRUST WITH AN EMPHASIS ON DESICCATION STRESS 1
ECOPHYSIOLOGICAL PERFORMANCE OF THE AEROTERRESTRIAL GREEN ALGA KLEBSORMIDIUM CRENULATUM (CHAROPHYCEAE, STREPTOPHYTA) ISOLATED FROM AN ALPINE SOIL CRUST WITH AN EMPHASIS ON DESICCATION STRESS 1
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从高山土壳中分离出来的陆生绿藻 Klebormidium CRENULATUM（藻类，链藻门）的生态生理学性能，重点关注干燥胁迫 1
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
A. Holzinger
中科院分区：
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作者：
U. Karsten;C. Lütz;A. Holzinger
克雷伯索米藻属（Klebsormidiales，链球菌门）的陆生丝状绿藻是生物土壤结皮的典型组成部分，存在于世界各地的干旱和半干旱生境中，包括高山地区。在本研究中，Klebsormidium crenulatum (Kütz.) Lokhorst 是从奥地利阿尔卑斯山林线以上的高山土壤结皮中分离出来的。在受控实验室条件下测量生长反应、光合性能和耐干燥性。 K. crenulatum 在相对较低的光子注量密度（分别为 30 和 21.9 μmol 光子 · m−2 · s−1）下表现出最佳的生长和最高的光合效率，表明光需求较低。它在 1.2 至 15 实用盐度单位 (psu) 之间的狭窄盐度范围内生长，表明具有明显的窄盐响应模式。温度从 5°C 升高到 40°C 对细齿堇菜的光合放氧和呼吸耗氧量产生不同的影响。虽然在低温（5°C–10°C）下光合作用相对较高，但呼吸作用无法检测到或处于非常低的水平。相反，在最高温度 40°C 时，光合作用受到抑制，呼吸作用不受影响，表明两个生理过程之间的温度敏感性存在很大差异。 K. crenulatum 在干燥条件下能够有效进行光合作用长达 2.5 小时，3 小时后下降至初始值的 15%。补液后 2 小时内完全恢复。所有生态生理学数据都解释了欧洲阿尔卑斯山高山地区土壤结皮中广泛存在的 K. crenulatum。
Aeroterrestrial filamentous green algae of the genus Klebsormidium (Klebsormidiales, Streptophyta) are typical components of biological soil crusts, which occur worldwide in arid and semiarid habitats including alpine regions. In the present study, Klebsormidium crenulatum (Kütz.) Lokhorst was isolated from an alpine soil crust above the timberline of the Austrian Alps. Growth responses, photosynthetic performance, and desiccation tolerance were measured under controlled laboratory conditions. K. crenulatum exhibited optimal growth and the highest photosynthetic efficiency under relatively low photon fluence densities (30 and 21.9 μmol photons · m−2 · s−1, respectively), indicating low‐light requirements. It grew in a narrow range of salinities between 1.2 and 15 practical salinity units (psu), pointing to a pronounced stenohaline response pattern. Increasing temperatures from 5°C to 40°C led to different effects on photosynthetic oxygen evolution and respiratory oxygen consumption in K. crenulatum. While at low temperatures (5°C–10°C) photosynthesis was relatively high, respiration was not detectable or was at a very low level. Conversely, at the highest temperature of 40°C, photosynthesis was inhibited, and respiration unaffected, indicating strong differences in temperature sensitivity between both physiological processes. K. crenulatum was capable of photosynthesizing efficiently for up to 2.5 h under desiccation, followed by a decrease to 15% of the initial value after 3 h. Complete recovery took place within 2 h after rehydration. All ecophysiological data explain the widespread abundance of K. crenulatum in soil crusts of the alpine regions of the European Alps.