Effects of High-Frequency Fluctuating Light on Photosynthe- sis and Production by Marine Macroalgae

高频（0.01-10赫兹）波动是浅海环境中光的显著特征。高频率波动已显示对陆生植物的光合作用和初级生产有重大影响，最近对海洋微藻也有重大影响。拟议的研究将检查高频光波动对底栖大型藻类crispus的光合生理和生产力的影响。植物将在各种恒定和波动的辐照度、c同化和生长速率下进行驯化，并对不同处理进行比较。波动光效应的机制将通过比较光收集特性、羧化酶活性、光吸收动力学以及代谢底物的池大小和周转率来检验。实验室实验的结果将与环境条件有关，通过比较在不同的原位光照制度下生长的植物的反应。总的来说，拟议的研究将提供关于高频率波动对海洋藻类的影响和响应机制的全面信息，这些影响来自高度可变和可定义的光环境。

High-frequency (0.01-10 Hz) fluctuations are prominent characteristics of light in shallow, marine environments. High frequency fluctuations have been shown to have significant effects on photosynthesis and primary production by terrestrial plants and, more recently, by marine microalgae. The proposed research will examine effects of high-frequency light fluctuations on the photosynthetic physiology and productivity of the benthic macroalga, Chondrus crispus. Plants will be acclimated under a variety of constant and fluctuating irradiance, C-assimilation, and growth rates will be compared for the different treatments. The mechanisms of fluctuating light effects will be examined by comparing light-harvesting characteristics, carboxylating enzyme activity, light absorption kinetics, and pool sizes and turnover rates of metabolic substrates. Results of laboratory experiments will be related to environmental conditions by comparing responses of plants grown under different in situ light regimes. Overall, the proposed research will provide comprehensive information about effects of high-frequency fluctuations and response mechanisms in a marine alga from a light environment which is both highly variable and definable.