不同光照对稀杯盔形珊瑚生长及钙化的影响

本研究于2015年3月份在徐闻珊瑚礁国家级自然保护区采集稀杯盔形珊瑚（Galaxea astreata），分解获得单枝实验珊瑚，实验室条件下进行四种波长光谱光强度渐变单因子对照试验，分别观察其在光谱波长、光强度渐变条件下的生长特性和代谢水平。结果显示，不同光谱在光强度240 μmol/m2/s条件下，稀杯盔形珊瑚单位面积叶绿素含量（A）和虫黄藻密度（Z）变化呈显著性差异（p＜0.05），除了碳水化合物（C），都在波长380~460 nm光谱光照条件下达到最大值，其中脂质含量百分比（L）是蛋白质（P）和C的10倍以上；不同光谱、光强度梯度条件下，光照条件下的钙化率（G_L）、净光合作用量（P_N）、总光合作用量（P_G）差异显著（p＜0.05），在一定范围内，G_L、P_G、P_N随着光强度增强而升高，当光强度超过光合效率光饱和值时，停止升高或开始降低；G_L/G_D和G_L/P_G比值也随着光强度增强而升高，比值变化范围分别在3.06~9.89和0.21~0.60之间，但P_G/P_N比值随着光强度增强而降低，变化范围在1.20~2.69之间。

Influence of different light on growth and calcification of Galaxea astreata

Nubbins from Galaxea astreata in March were dissected and cultured in unifactor and control experiment.By the survey of growth characteristics and metabolic level under a range of light wavelength and light intensities, The results suggested the four spectral quality (240 μmol photons/m2/s) produced significant impacts on the areal zooxanthellae density (Z) and chlorophyll-a content (A) and showed a significant differences between control and treatment (p < 0.05).Both parameters of peaked at 380~460 nm, except carbohydrate, lipid content to almost 10-fold higher values for the Protein(P) and Carbohydrate(C).The light-dependant calcification rates (G_L), net photosynthesis (P_N) and gross photosynthesis (P_G) showed significant difference among them under a range of light wavelength and light intensities (p < 0.05).The increases of light-dependant calcification rates(G_L), gross photosynthesis (P_G) and net photosynthesis (P_N) Along with the increase of light intensities, and begin to stop increase or decrease when the light intensities peaked at a threshold that was found between the light intensity and photosynthetic efficiency.Accordingly, The ratio of light-dependant calcification rates (G_L) to dark calcification rates (G_D) and light-dependant calcification rates (G_L) to gross photosynthesis (P_G)remains a similar variation curve and the ratio ranges from 3.06 to 9.89 and 0.21 to 0.60.However, The ratio gross photosynthesis (P_G) to net photosynthesis (P_N) begin to decrease Along with the increase of light intensities and the ratio ranges from 1.20 to 2.69.