ENTRAINMENT OF NITRATE IN THE FRASER-RIVER ESTUARY AND ITS BIOLOGICAL IMPLICATIONS .2. EFFECTS OF SPRING VS NEAP TIDES AND RIVER DISCHARGE

被引：34

作者：

YIN, KD ^{[1
]}

HARRISON, PJ ^{[1
]}

POND, S ^{[1
]}

BEAMISH, RJ ^{[1
]}

机构：

[1] FISHERIES & OCEANS CANADA,PACIFIC BIOL STN,NANAIMO,BC V9R 5K6,CANADA

来源：

ESTUARINE COASTAL AND SHELF SCIENCE | 1995年 / 40卷 / 05期

基金：

加拿大自然科学与工程研究理事会;

关键词：

NITRATE ENTRAINMENT; RIVERINE PLUME; ESTUARINE PLUME; SPRING TIDE; NEAP TIDE; RIVER DISCHARGE; FRASER RIVER; STRAIT OF GEORGIA;

D O I：

10.1006/ecss.1995.0036

中图分类号：

Q17 [水生生物学];

学科分类号：

071004 ;

摘要：

A 24-h time series of high-resolution vertical profiles of salinity, temperature, NO3 and fluorescence were taken during spring and neap tides at an anchored station (station 2) in the Strait of Georgia, 8 km seaward of the mouth of the Fraser River in order to estimate entrainment of NO3 resulting from the outflowing riverine plume. The time series confirmed that more NO3 was entrained during the spring tide (24 mmol m-2) than during the neap tide (17 mmol m-2). The contribution of the entrained NO3 was 2.3 and 1.6 times that of the river-borne NO3 during spring and neap tides, respectively. We hypothesize that spring tides cause stronger bottom stirring which results in higher NO3 concentrations in the deep seawater which is the source of NO3 that is entrained upward. The results from the times series taken during days of different river discharge show that during higher river discharge (9000 m3 s-1) more NO3 (72 mmol m-2) was entrained than during lower (6720 m3 s-1) river discharge (32 mmol m-2). The entrained NO3 was 5.4 times that of the river-borne NO3 during the higher river discharge and 3.3 times during the lower discharge. The mechanism which explains the greater NO3 entrainment is that greater river discharge pushes the estuarine plume seaward, further from the river mouth, and therefore there is a larger area of deep seawater (with higher NO3 concentrations) exposed directly to the riverine plume for entrainment.

引用

页码：529 / 544

页数：16

共 22 条

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