Mixing of Iron-Rich Coastal Waters with Nutrient-Rich HNLC Waters Leading to Enhanced Phytoplankton Biomass: a Focus on the Northwest Gulf of Alaska

富含铁的沿海水域与营养丰富的 HNLC 水域的混合导致浮游植物生物量增加：重点关注阿拉斯加西北湾

• 批准号: 0526601
• 负责人: Kenneth Bruland
• 金额: $ 64.95万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0526601&HistoricalAwards=false
• 关键词: Mixing; Iron; Rich; Coastal; Waters

A scientist from the University of California, Santa Cruz proposes to examine high-chlorophyll regions that develop at the boundaries of high-nitrate, iron-deplete, offshore waters and iron-rich, nitrate-poor, coastal water. Specifically, the researcher proposes to test the hypothesis that high biomass observed in satellite imagery in the northwestern Gulf of Alaska (GoA) during mid-summer months results from high river runoff into the Alaskan Coastal Current during this time of year, and mixing of this coastal water rich in dissolved and leachable particulate iron with the HNLC waters of the adjacent GoA via mesoscale eddies. To test the hypothesis, the PI will determine the distribution of dissolved and particulate iron (and other micronutrient trace metals) versus the distribution of macronutrients to assess the supply and demand of micro- and macronutrient elements in the northwestern GoA. In addition, the degree to which particulate iron is solubilized and becomes bioavailable will be determined using a series of grow out experiments with stable isotopes of iron. This data will also serve to fill in gaps for iron distributions in coastal regions. Another high chlorophyll region off Point Conception, CA will also be studied. In terms of broader impacts, this study will not only further our understanding of iron cycling in the northern GoA and off Point Conception, California, but provide much needed information on ecosystem productivity in these economically important coastal regions. Results from this project will be presented at local service clubs and in a display for K-12 students at the Seymour Discover Center of the Long Marine Lab. Training of graduate students and post-docs is included in the study.

来自加州大学圣克鲁斯分校的一位科学家建议研究在高硝酸盐、铁耗尽的近海沃茨和富铁、硝酸盐贫乏的沿海水域的边界处发展的高叶绿素区域。 具体而言，研究人员提出测试的假设，即在卫星图像中观察到的高生物量在阿拉斯加湾（果阿）在仲夏的几个月的结果，从高河流径流到阿拉斯加沿岸流在每年的这个时候，并混合这种沿海水富含溶解和可沥滤颗粒铁与HNLC沃茨的相邻的果阿通过中尺度涡。 为了检验这一假设，PI将确定溶解铁和颗粒铁（以及其他微量营养素痕量金属）的分布与常量营养素的分布，以评估果阿西北部微量和常量营养素的供求情况。 此外，将使用一系列具有铁的稳定同位素的生长实验来确定颗粒铁溶解并变得生物可利用的程度。 这些数据也将有助于填补沿海地区铁分布的空白。 另一个高叶绿素区关闭点概念，CA也将进行研究。 在更广泛的影响方面，这项研究不仅将进一步了解铁循环的北方果阿和关闭点概念，加州，但在这些经济重要的沿海地区的生态系统生产力提供急需的信息。 该项目的结果将在当地的服务俱乐部和在长期海洋实验室的西摩发现中心为K-12学生展示。 研究生和博士后的培训也包括在研究中。