摘要 : Temperature and irradiance are the most important factors affecting marine benthic microalgalphotosynthetic rates in temperate intertidal areas.Two temperate benthic diatoms species, Amphoracf. coffeaeformis (C. Agardh) Kutz. and ... 展开 Temperature and irradiance are the most important factors affecting marine benthic microalgalphotosynthetic rates in temperate intertidal areas.Two temperate benthic diatoms species, Amphoracf. coffeaeformis (C. Agardh) Kutz. and Cocconeis cf.sublittoralis Hendey, were investigated to determinehow their photosynthesis responded to temperaturesranging from 5 deg C to 50 deg C after short-term exposure(1 h) to a range of irradiance levels (0, 500, and1,100 mu mol photons . m~(-2) . s~(-1). Significant differences were observed between the temperatureresponses of maximum relative electron transportrate (rETRmax), photoacclimation index (E_k), photosynthetic efficiency (alpha), and effective quantumyield (DELTA F/F_m') in both species. A. coffeaeformis had agreater tolerance to higher temperatures than C. sublittoralis, with nonphotochemical quenching (NPQ)activated at temperatures of 45 deg C and 50 deg C. C. sublittoralis, however, demonstrated a more rapid rateof recovery at ambient temperatures. Temperaturesbetween 108C and 208C were determined to be optimal for photosynthesis for both species. High temperatures and irradiances caused a greater decreasein DELTA F/F_m' values. These results suggest that theeffects of temperature are species specific and thatshort-term exposure to adverse temperature slowsthe recovery process, which subsequently leads tophotoinhibition. 收起