Productivity in upwelling areas deduced from hydrographic and chemical fields1
Productivity in upwelling areas deduced from hydrographic and chemical fields1
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从水文和化学领域推断出上升流区域的生产力1
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
T. Packard
中科院分区：
文献类型：
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作者：
H. Minas;M. Minas;T. Packard
Broenkow的营养氧模型和Bowden的滞留时间的上升流沃茨的评估相结合，使我们能够计算“净社区生产”（NCP）在沿海上升流地区（西北非洲，西南非洲，秘鲁）和开放的上升流（哥斯达黎加圆顶）。由于NCP主要代表磷或氮方面的新产量，并且由于它来自主要产区的综合养分消耗，因此可以很好地了解这些地区的平均肥力。就碳而言，NCP在秘鲁海域平均为0.6 g C m-2 d-1，在非洲西南部海域平均为1.1 g C m-2 d-1，在非洲西北部海域平均为2.3 g C m-2 d-1。然而，秘鲁和非洲西南部每公里海岸线的生产预算要比非洲西北部大。秘鲁和西南非洲外海的活动较低，这与相对高营养低叶绿素（HNLC）的情况相对应，其特点是浮游植物现存量增长缓慢。这种HNLC的情况在哥斯达黎加圆顶非常明显，NCP值低至0.14 g C m-2 d-1。食草放牧在新鲜涌源水似乎是最合理的解释低叶绿素。这种种植浮游植物和延缓营养吸收的机制提供了一种将营养输入扩散到公海的方法。这也解释了在赤道上升流的表面沃茨氧不饱和（和CO，过饱和）的流行。通过使用西北非洲的数据和NCP和铵排泄率从文献中，我们可以计算出一个Eppley因子（pN 0，-：pNO，- f pNH，+）为0.64。
A combination of Broenkow’s nutrient oxygen model and Bowden’s residence time evaluation of upwelled waters enabled us to calculate the “net community production” (NCP) in coastal upwelling areas (NW Africa, SW Africa, Peru) and in an open upwelling (Costa Rica Dome). Since NCP represents mainly new production in terms of phosphorus or nitrogen, and since it derives from integrated nutrient consumption over the main production area, a good picture of the average fertility of these zones is obtained. In terms of carbon, NCP averaged 0.6 g C m-2 d-l off Peru, 1.1 off SW Africa, and 2.3 off NW Africa. However, production budget per kilometer of coastline is greater for both Peru and SW Africa than it is for NW Africa. The lower activities off Peru and off SW Africa correspond to a relatively high nutrient-low chlorophyll (HNLC) situation, characterized by a slowly growing phytoplankton standing stock. Such HNLC situations are greatly pronounced in the Costa Rica Dome, with NCP values as low as 0.14 g C m-2 d-l. Herbivorous grazing in the freshly upwelled source water appears to be the most plausible explanation for the low chlorophyll. This mechanism for cropping phytoplankton and retarding nutrient uptake provides a way to spread nutrient input to the open ocean. Italso explains the prevalence of oxygen undersaturation (and CO, oversaturation) in the surface waters of the equatorial upwelling. By using the NW African data and NCP and ammonium excretion rates from the literature we could calculate an Eppley ffactor (pN0, - : pNO,- f pNH,+) of 0.64.