...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Estuarine Coastal and Shelf Science >Seasonal dynamics of inorganic nutrients and phytoplankton biomass in the NW Alboran Sea
【24h】

Seasonal dynamics of inorganic nutrients and phytoplankton biomass in the NW Alboran Sea

机译：西北阿尔伯兰海中无机养分和浮游植物生物量的季节动态

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The seasonal dynamics of inorganic nutrients and phytoplankton biomass (chlorophyll a), and its relation with hydrological features, was studied in the NW Alboran Sea during four cruises conducted in February, April, July and October 2002. In the upper layers, the seasonal pattern of nutrient concentrations and their molar ratios (N:Si:P) was greatly influenced by hydrological conditions. The higher nutrient concentrations were observed during the spring cruise (2.54 μM NO_3~-, 0.21 uM PO_4~(3-) and 1.55 μM Si(OH)_4, on average), coinciding with the increase of salinity due to upwelling induced by westerlies. The lowest nutrient concentrations were observed during summer (< 0.54 μM NO_3~-, 0.13 μM PO_4~(3-) and 0.75 μM Si(OH)_4, on average), when the lower salinities were detected. Nutrient molar ratios (N:Si:P) followed the same seasonal pattern as nutrient distribution. During all the cruises, the ratio N:P in the top 20 m was lower than 16:1, indicating a NO_3~- deficiency relative to PO_4~(3-). The N:P ratio increased with depth, reaching values higher than 16:1 in the deeper layers (200-300 m). The N:Si ratio in the top 20 m was lower than 1:1, excepting during spring when N:Si ratios higher than 1:1 were observed in some stations due to the upwelling event. The N:Si ratio increased with depth, showing a maximum at 50-100 m (> 1.5:1), which indicates a shift towards Si-deficiency in these layers. The Si:P ratio was much lower than 16:1 throughout the water column during the four cruises. In general, the spatial and seasonal variation of phytoplankton biomass showed a strong coupling with hydrological and chemical fields. The higher chlorophyll a concentrations at the depth of the chlorophyll maximum were found in April (2.57 mg m~(-3) on average), while the lowest phytoplankton biomass corresponded to the winter cruise (0.74 mg m~(-3) on average). The low nitrate concentrations together with the low N:P ratios found in the upper layers (top 20 m) during the winter, summer and autumn cruises suggest that N-limitation could occur in these layers during great part of the year. However, N-limitation during the spring cruise was temporally overcome by nutrient enrichment caused by an intense wind-driven upwelling event.
机译：在2002年2月，4月，7月和10月进行的四次航行中，对西北西北部的无机养分和浮游植物生物量（叶绿素a）的季节动态及其与水文特征的关系进行了研究。营养成分浓度及其摩尔比（N：Si：P）受水文条件的影响很大。在春季巡航期间观察到较高的营养物浓度（平均为2.54μMNO_3〜-，0.21 uM PO_4〜（3-）和1.55μMSi（OH）_4），这与西风引起的上升导致盐度增加有关。在夏季，观察到最低的养分浓度（平均<0.54μMNO_3〜-，0.13μMPO_4〜（3-）和0.75μMSi（OH）_4）。营养摩尔比（N：Si：P）遵循与养分分布相同的季节性模式。在所有航行中，顶部20 m处的N：P比率均低于16：1，表明相对于PO_4〜（3-）而言，NO_3〜-缺乏。 N：P比率随深度增加而增加，在更深的层（200-300 m）中达到高于16：1的值。顶部20 m的N：Si比低于1：1，但春季期间由于上升事件在某些站点观测到N：Si比高于1：1。 N：Si比随深度增加，在50-100 m（> 1.5：1）处显示最大值，这表明这些层向Si缺乏的方向转变。在四次航行中，整个水柱中的Si：P比都远低于16：1。一般而言，浮游植物生物量的空间和季节变化与水文和化学领域表现出强烈的耦合。四月份在叶绿素最大深度处的叶绿素a浓度较高（平均为2.57 mg m〜（-3）），而浮游植物的最低生物量对应于冬季航行（平均0.74 mg m〜（-3））。 ）。在冬季，夏季和秋季航行期间，在上层（前20 m）中发现低的硝酸盐浓度和低的N：P比值，表明一年中的大部分时间，这些层中都可能发生N限制。但是，春季航行中的N限制暂时被强烈的风上升流事件引起的营养富集所克服。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号