Dark survival strategies in benthic diatoms from polar waters

极地水域底栖硅藻的暗生存策略

• 批准号: 73183771
• 负责人: Professor Dr. Burkhard Becker
• 金额: --
• 依托单位: Institut für Pflanzenwissenschaften
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/73183771?language=en
• 关键词: Dark; survival; strategies; benthic; diatoms

The highly productive microphytobenthos of polar shallow water zones is dominated by diatoms which have to cope with long periods of darkness between late autumn and early spring. Since the dark survival strategies of these organisms are almost unstudied, a comprehensive and precise evaluation of the underlying mechanisms will be carried out under controlled conditions in the laboratory with representative species abundant in the Arctic Kongsfjorden and the Antarctic Potter Cove. The mechanisms to be studied include the maximum survival period which will be determined using various cell biological markers (macromolecular composition, ultrastructure, viability, activity) as well as genetic markers (expression of functional genes involved in the degradation of chrysolaminaran and lipids). In addition, the capability to recover after re-irradiation by measuring growth and photosynthesis, and the effect of temperature on the dark survival potential will be evaluated. Arctic and Antarctic benthic diatoms will be compared to outline specific response patterns which are probably related to the different cold water history of both regions and hence to a different degree of adaptation to extreme low temperatures in the respective taxa. If environmental changes such as the observed Arctic warming are negatively affecting the dark survival potential of benthic diatoms, their ecological function as important primary producers in polar regions may be strongly reduced with consequences for all higher trophic levels.

极地浅水区高产的微型底栖植物以硅藻为主，它们必须应对深秋和早春之间的长时间黑暗。由于这些生物的黑暗生存策略几乎未被研究，因此将在实验室的受控条件下以北极孔斯峡湾和南极波特湾丰富的代表性物种对其潜在机制进行全面而精确的评估。要研究的机制包括最大存活期，该最长存活期将使用各种细胞生物标记（大分子组成、超微结构、活力、活性）以及遗传标记（参与金藻多糖和脂质降解的功能基因的表达）来确定。此外，将通过测量生长和光合作用来评估重新照射后的恢复能力，以及温度对黑暗生存潜力的影响。将比较北极和南极底栖硅藻，以勾勒出特定的响应模式，这些响应模式可能与两个地区不同的冷水历史有关，因此与各自分类单元对极端低温的不同程度的适应有关。如果环境变化（例如观察到的北极变暖）对底栖硅藻的黑暗生存潜力产生负面影响，那么它们作为极地地区重要初级生产者的生态功能可能会大大降低，从而对所有更高的营养级产生影响。