Hydrodynamic Regulation of Reproduction in Fucoid Algae: A Regional Model and Consequences for Population Structure

岩藻类藻类繁殖的水动力调节：区域模型及其对种群结构的影响

• 批准号: 0099043
• 负责人: Susan Brawley
• 金额: $ 39万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2006-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0099043&HistoricalAwards=false
• 关键词: Hydrodynamic; Regulation; Reproduction; Fucoid; Algae

Fucoid algae dominate most rocky shores across the north Atlantic and contribute substantially to structuring of the coastal ecosystem. Reproduction in fucoid algae is sensitive to hydrodynamic conditions, resulting in high fertilization success because gamete release occurs only under calm conditions. These findings have important implications for asynchrony in gamete release between populations and the scale of population isolation. This study will 1) test a nascent model describing when successful fucoid reproduction can occur, 2) determine whether hybridization between Fucus vesiculosus and other fucoid algae occurs when gamete release is delayed by turbulent conditions, and 3) analyze whether genetic differentiation in F. vesiculosus is correlated with variable hydrologic conditions due to coastal topography. Quantitative data on gamete release at multiple sites on opposite sides of coastal points (and smaller features) will be collected. This will determine whether gamete release in fucoids occurs at different times over small spatial scales due to variable wave and wind exposures across opposite sides of the undulating coastline. Species-specific monoclonal antibodies to recognize fucoid sperm are available; they and the required pump/concentration apparatus have been tested successfully at Pemaquid Point. Local environmental data (e.g., wind speed, light levels, water motion) will be collected and compared with data from monitoring systems such as NOAA's National Data Buoy Center stations. Maine shores have been stable for thousands of years; if the coastal F. vesiculosus is reproductively isolated in topographic fragments, population genetic structure may be affected. This will be tested with AFLP analysis of randomly collected adults. Storms delay gamete release from fucoid algae, and laboratory studies predict that natural hybridization will increase sharply if over-mature eggs participate in fertilizations. This will be tested in field studies of hybridization potential, achieved hybridization, and identification of hybrid position in the intertidal zone in F. spiralis versus F. vesiculosus (Maine) and F. serratus (an exotic) versus F. vesiculosus (Nova Scotia). The hypothesized environmental interaction with development as a regulator of hybridization and genetic structure in F. vesiculosus (and other fucoids) could have strong local and biogeographic effects on intertidal communities across the north Atlantic. Among the products of this research will be a robust regional model for fucoid reproduction as a function of relevant physical factors (i.e., wind speed and direction, wave height, light levels).

岩藻在北大西洋的大多数岩石海岸占主导地位，并对沿海生态系统的结构做出了重大贡献。岩藻的繁殖对水动力条件很敏感，导致受精成功率很高，因为配子释放只发生在平静的条件下。这些研究结果对种群间配子释放的相关性和种群隔离的规模具有重要意义。这项研究将1）测试一个新生模型，描述何时可以发生成功的岩藻繁殖，2）确定当配子释放被湍流条件延迟时，墨角藻和其他岩藻之间是否发生杂交，以及3）分析F. vesiculosus与由于沿海地形而变化的水文条件相关。将收集海岸点（和较小地物）两侧多个地点配子释放的定量数据。这将决定是否配子释放岩藻体发生在不同的时间在小的空间尺度上，由于可变的波浪和风暴露在起伏的海岸线的相对两侧。可以获得识别岩藻精子的物种特异性单克隆抗体;它们和所需的泵/浓缩装置已在Pemaquid Point成功测试。当地环境数据（例如，风速、光照水平、水流运动）将被收集，并与来自NOAA国家数据浮标中心站等监测系统的数据进行比较。缅因州的海岸已经稳定了几千年; vesiculosus在地形片段中繁殖隔离，可能影响种群遗传结构。这将通过随机收集的成年人的AFLP分析进行测试。风暴会延迟岩藻的配子释放，实验室研究预测，如果过成熟的卵子参与受精，自然杂交将急剧增加。这将在现场研究杂交潜力，实现杂交，并确定杂种的位置在潮间带的F。spiralis与F. vesiculosus（缅因州）和F. serratus（一种外来种）与F. vesiculosus（新斯科舍省）。假设环境与发育的相互作用是F. vesiculosus（和其他岩藻）可能对北大西洋的潮间带群落产生强烈的局部和地理影响。在这项研究的产品中，将有一个鲁棒的区域模型，用于岩藻生殖作为相关物理因素的函数（即，风速和风向、波高、光照水平）。