【摘要】：沉積物-水界面上磷的吸附解吸是海域磷素遷移轉化的重要方式并且直接影響海水中磷的濃度和富營養(yǎng)化水平。埕島采油平臺改建魚礁海域人工魚礁的投放和退役采油平臺鑄鐵的腐蝕形成了研究區(qū)獨特的沉積物環(huán)境。本文通過等溫吸附解吸的方法模擬固體濃度、pH和針鐵礦含量對沉積物-水界面上的磷吸附解吸的影響,主要探討了影響因素對吸附量、EPCo等重要吸附參數(shù)產生的作用。采用修正的Langmuir、 Freundlich以及線性回歸的方法對等溫吸附實驗結果進行擬合,并對其在EPC0計算方面的作用進行比較。最后,結合退役采油平臺海域投礁后期調查與實驗所得規(guī)律,判斷退役采油平臺海域磷酸鹽濃度的變化趨勢,對富營養(yǎng)化水平作出預估。主要結論如下： (1)固體濃度升高,EPCo值隨之增大,說明在一定程度上固體濃度升高有利于沉積物中磷的釋放,但EPC0值整體上仍小于海域底層海水磷濃度,表明沉積物主要表現(xiàn)為對磷的吸附作用。因此研究海域中的項目施工引起的懸浮物濃度增大不會改變沉積物磷匯的作用。 (2)研究海域表層沉積物對磷的吸附量隨pH在6.5～8.5之間的小幅度增大表現(xiàn)為先增大后減小,在略偏堿性范圍內(pH值為7.71時)出現(xiàn)最大吸附量。小幅度的pH變化對吸附參數(shù)的影響較小,等溫吸附實驗顯示偏酸或偏堿都會使磷傾向于吸附,但這種作用十分微弱。 (3)針鐵礦含量增大對吸附的影響顯著。針鐵礦含量增大,PAC與NAP的增大說明針鐵礦特殊的表面性質使沉積物更易于固定水中的磷,而表現(xiàn)為吸附解吸磷的能力同時增強；EPC0輕微減小,Kp明顯增大,說明從表觀上來看沉積物易于吸附磷。 (4)通過對比固體濃度、pH和針鐵礦含量對吸附產生的影響,并結合海域中影響因子的變化空間,推出固體濃度是該海域中磷吸附解吸的最主要的影響因子。在人力物力有限的條件下,可著重研究固體濃度對吸附產生的影響,以從整體上把握變化趨勢。 (5)對EPC0的分析表明,固體濃度為沉積物-水界面磷吸附解吸的最主要的影響因子；沉積物組成即針鐵礦含量的升高對EPC0未表現(xiàn)出明顯影響,但針鐵礦的添入與否對EPCo有一定程度的影響。擬合數(shù)據(jù)表明,修正后的Langmuir和Freundlich可以較可靠的計算EPC0值,但吸附量與初始濃度做線性回歸的方法出現(xiàn)較大的偏差,不適合計算本研究區(qū)域沉積物磷吸附的EPC0值。 (6)調查顯示,海域磷酸鹽與固體濃度表現(xiàn)出較為一致的變化規(guī)律,表明固體濃度是沉積物-水界面磷吸附解吸的重要影響因子。懸浮沉積物可以吸附水體中的磷酸鹽,是海水中磷的匯�？傮w上不會因為固體濃度的增大,導致海水中磷濃度的突然升高,但也不排除極端狀況下,固體濃度的大幅升高引起的磷釋放。退役采油平臺海域整體上不會因為沉積環(huán)境的變化而導致磷的大量釋放引起海域富營養(yǎng)化,但也存在局部富營養(yǎng)水平偏高的可能。
[Abstract]:Adsorption and desorption of phosphorus on the sediment-water interface is an important way of phosphorus transport and transformation in the sea area and directly affects the concentration and eutrophication of phosphorus in the sea water. Adsorption and desorption methods simulate the effects of solid concentration, pH and goethite content on phosphorus adsorption and desorption at the sediment-water interface. The effects of influencing factors on adsorption capacity, EPCo and other important adsorption parameters are discussed. The experimental results of isothermal adsorption are fitted by modified Langmuir, Freundlich and linear regression methods. Finally, the change trend of phosphate concentration in the area of decommissioned platforms is judged and the eutrophication level is predicted by combining the investigation and experimental results of the decommissioned platforms.
(1) With the increase of solid concentration, the EPCo value increases, which indicates that the increase of solid concentration is beneficial to the release of phosphorus from sediments to a certain extent, but the EPC0 value is still lower than the phosphorus concentration in the bottom seawater, indicating that the sediments mainly show phosphorus adsorption. Changing the role of phosphorus in sediments.
(2) The adsorption capacity of phosphorus on the surface sediments of the sea area increases first and then decreases with the small increase of pH between 6.5 and 8.5, and the maximum adsorption capacity appears in the slightly alkaline range (pH 7.71). The small change of pH has little effect on the adsorption parameters, and isothermal adsorption experiments show that both acidic and alkaline can make phosphorus tend to adsorption. But this effect is very weak.
(3) The increase of goethite content and PAC and NAP indicated that the special surface properties of goethite made the sediments more easily to fix phosphorus in water, and the adsorption and desorption capacity of goethite increased at the same time. EPC0 decreased slightly and Kp increased significantly, indicating that the sediments were easy to adsorb phosphorus from the surface.
(4) By comparing the effects of solid concentration, pH and goethite content on adsorption and combining with the changing space of influencing factors in the sea area, it is deduced that the solid concentration is the most important influencing factor of phosphorus adsorption and desorption in the sea area. Grasp the trend of change.
(5) The analysis of EPC0 shows that the solid concentration is the most important factor affecting the adsorption and desorption of phosphorus at the sediment-water interface; the elevation of goethite content in sediments has no obvious effect on EPC0, but the addition of goethite has some effect on EPCo. The fitting data show that the modified Langmuir and Freundlich can be compared. Reliable calculation of EPC0 value, but the method of linear regression between adsorption capacity and initial concentration is not suitable for calculating the EPC0 value of phosphorus adsorption in sediments of this study area.
(6) The results show that the concentration of phosphate and solids in the sea area shows a relatively consistent change law, indicating that the solid concentration is an important factor affecting the adsorption and desorption of phosphorus at the sediment-water interface. The sudden increase of phosphorus content in the decommissioned oil platforms will not lead to the eutrophication of the sea area as a whole because of the change of sedimentary environment, but there is also the possibility of high local eutrophication.
【學位授予單位】：青島大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：X55

【參考文獻】

相關期刊論文 前10條

1 王雨春,萬國江,黃榮貴,鄒申清,陳剛才;湖泊現(xiàn)代化沉積物中磷的地球化學作用及環(huán)境效應[J];重慶環(huán)境科學;2000年04期

2 徐軼群,熊慧欣,趙秀蘭;底泥磷的吸附與釋放研究進展[J];重慶環(huán)境科學;2003年11期

3 劉敏,侯立軍,許世遠,歐冬妮,張斌亮,劉巧梅,楊毅;長江河口潮灘表層沉積物對磷酸鹽的吸附特征[J];地理學報;2002年04期

4 王圣瑞;金相燦;龐燕;;湖泊沉積物對磷的吸附特征及其吸附熱力學參數(shù)[J];地理研究;2006年01期

5 馮海艷;李文霞;楊忠芳;阮曉紅;刑雅囡;;蘇州城市河道底泥對磷酸鹽的吸附與釋放特征[J];地學前緣;2006年01期

6 羅雪梅;何孟常;劉昌明;;黃河三角洲地區(qū)濕地土壤對多環(huán)芳烴的吸附特征[J];環(huán)境化學;2007年02期

7 龐燕,金相燦,王圣瑞,孟凡德,周小寧;長江中下游淺水湖沉積物對磷的吸附特征——吸附等溫線和吸附/解吸平衡質量濃度[J];環(huán)境科學研究;2004年S1期

8 王庭健，蘇睿，金相燦, 夏忠林，，林漪，方世裘;城市富營養(yǎng)湖泊沉積物中磷負荷及其釋放對水質的影響[J];環(huán)境科學研究;1994年04期

9 安文超;李小明;;南四湖及主要入湖河流表層沉積物對磷酸鹽的吸附特征[J];環(huán)境科學;2008年05期

10 王曉麗;潘綱;包華影;張憲偉;陳灝;郭博書;;黃河中下游沉積物對磷酸鹽的吸附特征[J];環(huán)境科學;2008年08期

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