本文選題：長江口 + 水動力箱式模型　； 參考：《中國科學(xué)院研究生院（海洋研究所）》2014年博士論文

【摘要】：長江口及鄰近水域（30.5°N-32°N,122°E-123°30′E）是我國近海富營養(yǎng)化的典型水域，其物質(zhì)通量研究具有重要意義。傳統(tǒng)的“水-鹽-營養(yǎng)鹽”箱式模型是海岸帶陸海相互作用研究計劃（LOICZ）研究河口與近岸物質(zhì)通量的一種穩(wěn)態(tài)模式。該模式?jīng)]有充分考慮研究區(qū)域的水動力因素，模式結(jié)果受箱體劃分影響很大，只能估算鹽度差異明顯的界面之間的物質(zhì)通量，對與海岸線平行以及流系復(fù)雜多變水域的物質(zhì)通量估算無能為力。 針對長江口及鄰近水域流系復(fù)雜多變的特點(diǎn)，本研究嘗試對傳統(tǒng)箱式模型進(jìn)行改進(jìn)。本研究將物質(zhì)輸運(yùn)過程正交分解為水平方向的物質(zhì)輸運(yùn)和垂直方向的物質(zhì)輸運(yùn)，水平與垂直方向的物質(zhì)輸運(yùn)分別分為對流引起的物質(zhì)輸運(yùn)和擴(kuò)散引起的物質(zhì)輸運(yùn)。以區(qū)域海洋模式系統(tǒng)（ROMS）為基礎(chǔ)，通過Matlab編程，，將水動力模型的流場數(shù)據(jù)準(zhǔn)確匹配到箱式模型的箱體邊界上，實(shí)現(xiàn)了水動力模型與箱式模型的聯(lián)接，成功構(gòu)建了基于水動力模型的改進(jìn)的箱式模型（本研究簡稱為“水動力箱式模型”）。 運(yùn)用構(gòu)建的水動力箱式模型，計算并闡釋了研究區(qū)域的水平水通量、垂向水通量和邊界水通量的空間分布與季節(jié)變化，探討分析了研究區(qū)域水通量的動力因素與機(jī)制，以及研究區(qū)域水體交換與缺氧之間的關(guān)系，為該水域物質(zhì)通量研究提供了準(zhǔn)確的水量基礎(chǔ)。在此基礎(chǔ)上，利用2005年2月、5月、8月、11月4個航次的監(jiān)測數(shù)據(jù)，計算并闡釋了研究區(qū)域營養(yǎng)鹽的水平通量、垂向通量和邊界通量及其營養(yǎng)鹽結(jié)構(gòu)的空間分布與季節(jié)變化，探討分析了研究區(qū)域營養(yǎng)鹽通量的動力因素與機(jī)制。 研究表明，表層水體水平水通量的季節(jié)排序?yàn)槎厩锛鞠募敬杭�；底層水體水平水通量的季節(jié)排序?yàn)橄募敬杭径厩锛�；秋、冬季底層水通量約比表層小1個數(shù)量級，夏季底層水通量約為表層的1/2，春季表、底層水通量差別最小。研究區(qū)域水通量整體受季風(fēng)控制，季風(fēng)使水體在南-北方向上季節(jié)性交替輸運(yùn)，臺灣暖流對春、夏季底層水體向北輸運(yùn)具有重要作用，CDW、地形、向岸風(fēng)等多種因素對水通量的時空分布態(tài)勢具有重要作用。夏季上升流水通量為18.53m3/s，春季為12.55m3/s，冬季為13.07m3/s，秋季為14.25m3/s。西邊界水通量方向全年向海。南、北邊界的表層水通量與季風(fēng)方向總體一致。東邊界水通量方向規(guī)律不明顯。南、北邊界的水通量約大于西邊界一個數(shù)量級。東邊界水通量，除春、秋季以外，明顯小于西邊界。秋、冬季南、北邊界的表層水通量約比底層水通量大1個數(shù)量級，春季約為底層水通量的1/2，夏季約為底層水通量的兩倍。經(jīng)東邊界直接進(jìn)入123.5°E以東外海水域的水通量極少（夏季5.41m3/s），且明顯小于春、秋季經(jīng)東邊界自東部外海流入的水通量（12.45m3/s、27.75m3/s）。全年計算，約187.73m3/s的水通量自南邊界流出研究區(qū)域，后經(jīng)海洋環(huán)流系統(tǒng)間接入海。研究區(qū)域水體交換主要依賴季風(fēng)方向、同層水體之間的的水平水通量。該水域底層水體缺氧的本質(zhì)原因是躍層阻隔了表、底層水體之間的氧氣交換。 表層水體水平營養(yǎng)鹽通量的季節(jié)排序?yàn)槎厩锛鞠募敬杭�；底層水體水平營養(yǎng)鹽通量的季節(jié)排序?yàn)橄募敬杭径厩锛�；表層水體水平營養(yǎng)鹽通量的空間差異與季節(jié)變化均顯著大于底層水體。研究區(qū)域營養(yǎng)鹽通量主要受物理作用控制，以生化作用為輔。與水通量相似，季風(fēng)使?fàn)I養(yǎng)鹽在南-北方向上季節(jié)性交替輸運(yùn)，臺灣暖流對春、夏季底層營養(yǎng)鹽向北輸運(yùn)具有重要作用，是春、夏季長江徑流影響范圍向東擴(kuò)展的重要限制因子，此外，垂向營養(yǎng)鹽通量補(bǔ)給、外海水團(tuán)入侵和初級生產(chǎn)消耗等多種因素對營養(yǎng)鹽通量的時空分布態(tài)勢具有重要作用。 垂向DIP通量是DIP的重要來源。垂向營養(yǎng)鹽通量的總體特征主要是由上升流通量的時空分布決定的。同一季節(jié)的上升流營養(yǎng)鹽通量顯著大于向上擴(kuò)散的營養(yǎng)鹽通量，且上升流營養(yǎng)鹽通量與向上擴(kuò)散的營養(yǎng)鹽通量的產(chǎn)生區(qū)域基本重合。春、夏季的上升流營養(yǎng)鹽通量和向上擴(kuò)散的營養(yǎng)鹽通量均顯著大于秋、冬季。DIP上升流通量(5.83mol/s)和向上擴(kuò)散通量(5.55mol/s)最大值均發(fā)生在夏季，但春季垂向通量對其影響最大。春季DIN、DSI垂向通量分別比水平通量少3-7倍、3-5倍，DIP垂向通量與水平通量接近相等；夏季DIN、DSI、DIP垂向通量分別比水平通量少3-6倍、5-10倍和5-8倍；秋、冬季，三種營養(yǎng)鹽垂向通量均比水平通量小2個數(shù)量級。 研究發(fā)現(xiàn)，同一季節(jié)流經(jīng)南、北邊界的營養(yǎng)鹽通量均顯著大于流經(jīng)東、西邊界的營養(yǎng)鹽通量。四個邊界中，經(jīng)東邊界與東部外海水體交換的營養(yǎng)鹽通量最小，比經(jīng)西邊界流入的營養(yǎng)鹽通量小大約1-2個數(shù)量級。西邊界營養(yǎng)鹽通量方向終年向海，南、北邊界營養(yǎng)鹽通量方向與季風(fēng)方向基本一致，秋、冬季南向，春、夏季北向。但秋季為季風(fēng)轉(zhuǎn)換期，北邊界表、底層營養(yǎng)鹽通量方向相反，表層南向，底層北向。東邊界營養(yǎng)鹽通量方向規(guī)律不明顯。研究區(qū)域扮演著營養(yǎng)鹽從黃海向東海輸送的“中轉(zhuǎn)站”角色。來自西邊界的營養(yǎng)鹽通量主要被局限在122.5°E以西的近岸區(qū)域，被直接輸送到123.5°E以東外海的極少。全年計算，約7149.82mol/s DIN，4097.97mol/s DSI,115.42mol/s DIP自南邊界流出研究區(qū)域。 相比傳統(tǒng)箱式模型，水動力箱式模型彌補(bǔ)了傳統(tǒng)箱式模型未能充分考慮水動力因素的缺陷，對復(fù)雜水動力環(huán)境下的營養(yǎng)鹽通量估算具有明顯優(yōu)勢，為河口物質(zhì)通量研究提供方法借鑒。
[Abstract]:The model of " water - salt - nutrient " box model is a steady state model for studying the flux of river mouth and coastal matter . The traditional " water - salt - nutrient salt " box model is a steady state model for studying the flux of river mouth and coastal matter .

Based on the regional ocean model system ( ROMS ) , the flow field data of the hydrodynamic model is accurately matched to the box boundary of the box model , and an improved box model based on the hydrodynamic model is successfully constructed ( this study is simply referred to as " hydrodynamic box model " ) .

This paper calculates and explains the spatial distribution and seasonal variation of the water flux , vertical water flux and boundary water flux in the study area by using the constructed hydrodynamic box model , and studies the dynamic factors and mechanism of the regional water flux , and studies the relationship between water exchange and anoxia in the area . Based on this , the paper calculates and explains the spatial distribution and seasonal variation of the nutrient salt in the study area , and discusses the dynamic factors and mechanism of the nutrient salt flux in the study area .

The results show that the seasonal ranking of the horizontal water flux in the surface water is the spring of autumn in winter in winter ;
The seasonal ranking of the level water flux in the bottom water body is autumn in spring in summer ;
In autumn , the water flux in the north boundary is about 1 / 2 of the surface layer , the spring is 12.55m3 / s , the winter is 13.07m3 / s , the spring is 12.55m3 / s , the spring is 13.07m3 / s and the autumn is 14.25m3 / s . For the whole year , the water flux of about 187.73m3 / s flows out of the study area from the south boundary , and then is directly entered into the sea through the ocean circulation system . The research area water body exchange mainly depends on the monsoon direction and the horizontal water flux between the same layer water body . The essential reason of the anoxic of the bottom water body of the water body is that the jump layer blocks the oxygen exchange between the table and the bottom water body .

The seasonal ranking of the level nutrient flux in the surface water body is winter autumn summer spring ;
Seasonal ordering of the level nutrient flux in the bottom water body is autumn in spring in summer ;
The seasonal variation of nutrient salt flux in the surface water body is significantly greater than that of the underlying water body . The research area nutrient flux is mainly controlled by the physical action , and the seasonal alternation of nutrient salt in the South - North direction is important to the north transport .

Vertical DIP flux is an important source of DIP . The overall characteristic of vertical nutrient flux is determined by the space - time distribution of upwelling flux . The flux of upwelling nutrient salt in the same season is significantly greater than that of the upward diffusion . In spring and summer , the flux of nutrient salt and the flux of upward diffusion are significantly higher than those in autumn and winter . In spring , the vertical flux of DIP is 3 - 7 times less than the horizontal flux , 3 - 5 times higher than that of the horizontal flux , and the vertical flux of DIP is nearly equal to the horizontal flux .
in summer , that vertical flux of din , dsi and dip is 3 - 6 times , 5 - 10 times and 5 - 8 times less than the horizontal flux , respectively ;
In autumn and winter , the vertical flux of three nutrient salts is 2 orders of magnitude smaller than that of the horizontal flux .

The study shows that the fluxes of nutrient salts flowing through the south and north boundary in the same season are significantly larger than those flowing through the eastern and western boundaries . The fluxes of nutrient salts in the eastern boundary and the East China Sea are the smallest , which is about 1 - 2 orders of magnitude smaller than that of the western boundary . However , the nutrient salt flux from the west boundary is mainly confined to the coastal areas in the east China Sea . The study area is mainly confined to the outer sea of 123.5 擄 E . The study area is calculated at about 7149.82mol / s DIN , 4097.97mol / s dsi and 1150.42mol / s DIP from the south boundary .

Compared with the traditional box model , the water dynamic box model makes up the failure of the traditional box model to fully consider the water power factor , and has obvious advantages to the estimation of the nutrient salt flux under the complex hydrodynamic environment , and provides a method for the research of the estuary material flux .
【學(xué)位授予單位】：中國科學(xué)院研究生院（海洋研究所）
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TV14;X143

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 潘玉球,,黃樹生;長江沖淡水輸運(yùn)和擴(kuò)散途徑的分析[J];東海海洋;1997年02期

2 李新艷;王芳;楊麗標(biāo);晏維金;;河流輸送泥沙和顆粒態(tài)生源要素通量研究進(jìn)展[J];地理科學(xué)進(jìn)展;2009年04期

3 程天文,趙楚年;我國沿岸入海河川徑流量與輸沙量的估算[J];地理學(xué)報;1984年04期

4 汪亞平;潘少明;H.V.Wang;高建華;楊e

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