Late Holocene centennial to millennial-scale variability in lower trophic level productivity off southern Hokkaido, Japan, and its response to dissolved iron-replete Coastal Oyashio dynamics
Late Holocene centennial to millennial-scale variability in lower trophic level productivity off southern Hokkaido, Japan, and its response to dissolved iron-replete Coastal Oyashio dynamics
复制标题
日本北海道南部附近全新世晚期百年至千年尺度的低营养级生产力变化及其对溶解铁丰富的沿海亲潮动态的响应
DOI：
10.1017/qua.2021.71
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发表时间：
2022
影响因子：
2.3
通讯作者：
Irino Tomohisa
中科院分区：
文献类型：
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作者：
Kuwae Michinobu;Tsugeki Narumi;Finney Bruce P.;Tani Yukinori;Onodera Jonaotaro;Kiyoto Mako;Kusaka Mitsukuni;Sagawa Takuya;Nakamura Yugo;Ohnishi Hiroji;Kuroda Hiroshi;Okuda Noboru;Ohta Tamihisa;Ikehara Minoru;Irino Tomohisa
人们对海洋食物链在百年和更长时间尺度上从初级营养水平到更高营养水平的动态知之甚少，特别是在溶解铁供应限制初级生产力的情况下。为了阐明沿海Oyashio(CO)生物生产力的长期动态，我们重建了CO过去3000年来的低营养层生产力。结果表明，作为初级生产力指标的Chl-a(叶绿素a及其衍生物)和生物源蛋白石，以及作为浮游动物生产力指标的甾基氯酸酯(SCES)，其浓度和质量积累速率从公元400年左右开始呈现千年尺度的增长趋势和百年尺度的变化。SCE与Chl-a呈正相关，表明浮游动物生产力的变化是由初级生产力自下而上的控制引起的。Chl-a和SCES显示出同步的百年尺度格局，CO输送的与海冰有关的硅藻种类相对丰富，鄂霍次克海中水的通风指数也有变化。这种同步格局表明，春季开花期间较低的营养层生产力对富铁的CO强度做出了响应。
Little is known about the dynamics of marine food chains spanning primary to higher trophic levels on centennial and longer timescales, especially where the supply of dissolved iron limits primary productivity. To elucidate the long-term dynamics of biological productivity in the Coastal Oyashio (CO), which is a major pathway for transporting dissolved iron into the western North Pacific from winter to spring, we reconstructed the lower trophic level productivity over the last 3000 years in the CO. Our results demonstrate that the concentrations and mass accumulation rates of both Chl-a (chlorophyll a and its derivatives) and biogenic opal used as proxies of primary productivity, and steryl chlorin esters (SCEs) used as that of zooplankton productivity, show a millennial-scale increasing trend and centennial-scale variability beginning ca. AD 400. SCEs were positively correlated with Chl-a, indicating that changes in zooplankton productivity were induced by bottom-up control of primary productivity. The Chl-a and SCEs showed synchronous centennial-scale patterns with a relative abundance of sea-ice-associated diatom species transported by CO, and with a ventilation index in the Okhotsk Sea Intermediate Water. This synchronous pattern indicates that lower trophic-level productivity during the spring bloom responded to the intensity of iron-replete CO.