The Influence of Fetch on the Holocene Thermal Structure of Hidden Lake, Glacier National Park
The Influence of Fetch on the Holocene Thermal Structure of Hidden Lake, Glacier National Park
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Fetch对冰川国家公园隐湖全新世热结构的影响
DOI：
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发表时间：
2019
影响因子：
2.9
通讯作者：
Trisha L. Spanbauer
中科院分区：
文献类型：
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作者：
J. Stone;J. Saros;Trisha L. Spanbauer
1.翻译后摘要我们使用三维建模的隐湖，蒙大拿州的盆地，以评估有效的取气的影响，推断在整个全新世的混合深度的变化。隐湖盆地的特点是复杂的地貌;例如，湖盆的三维建模表明，湖平面下降两米将导致湖盆最深处与湖的其他部分完全隔离。我们的模型表明，在隐藏湖的湖面高程的微小变化会产生阈值样的响应，在有效的取，这反过来又会产生深远的影响，平均湖泊混合深度。隐湖现今的浮游硅藻群落由三个物种组成。新生态学实验揭示了混合深度和营养水平对这些物种生长速率的影响。从湖盆最深处收集的沉积物岩心跨越了过去8,640年，对硅藻进行了分析。在这里，我们将展示如何通过全新世的变化来解释隐湖的热结构的修改在占主导地位的浮游硅藻物种的变化。此外，从隐湖的有效水分和热结构的时间推断的变化进行了比较，晚全新世模式重建从其他区域湖泊记录。在8.64 - 7.61 ka之间，隐湖的硅藻记录表明，该湖是深而新鲜的，尽管比现代湖略低。7.61 ka后，水位上升，扩大了底栖硅藻的栖息地。6.18 ~ 4.13ka，湖平面下降，季节分层增强。1.4 ka后，湖泊变得更深，分层的影响，增强取。我们认为，在有效的取物的变化可能会发挥重要的作用，和underexplored，在南极硅藻群落结构在较长的时间尺度上的作用，应该更广泛地考虑在古湖泊学研究。
1. Abstract We use three-dimensional modeling of the basin of Hidden Lake, Montana, to assess the influence of effective fetch on diatom-inferred changes in mixing depths throughout the Holocene. The basin of Hidden Lake is characterized by a complex morphometry; for example, three-dimensional modeling of the lake basin indicates that a decrease in lake level of two meters would result in complete isolation of the deepest part of the lake basin from the rest of the lake. Our model suggests that small changes in the lake surface elevation at Hidden Lake would produce threshold-like responses in effective fetch, which in turn would have a profound influence on average lake mixing depth. The present-day planktic diatom community of Hidden Lake is comprised of three species. Neo-ecological experiments revealed the effect of mixing depth and nutrient levels on growth rates of these species. A sediment core collected from the deepest part of the lake basin and spanning the last 8,640 years was analyzed for diatoms. Here we show how changes in fetch through the Holocene explain changes in the dominant planktic diatom species by modification of the thermal structure of Hidden Lake. Additionally, the timing of diatom-inferred changes in effective moisture and thermal structure from Hidden Lake were compared to late Holocene patterns reconstructed from other regional lake records. Between 8.64 – 7.61 ka the diatom record from Hidden Lake suggests that the lake was deep and fresh, although somewhat lower than the modern lake. After 7.61 ka, water levels rose, expanding the available benthic diatom habitat. Between 6.18 –4.13 ka, lake level declined and seasonal stratification was enhanced. After 1.4 ka, the lake became deeper and less stratified in response to the effects of enhanced fetch. We argue that changes in effective fetch may play an important, and underexplored, role in planktic diatom community structure over longer time scales and should be more broadly considered in paleolimnological studies.
影响因子：
3.7
作者：
Dubovskaya OP;Tang KW;Gladyshev MI;Kirillin G;Buseva Z;Kasprzak P;Tolomeev AP;Grossart HP
通讯作者：
Grossart HP