|Alternative Title||Detection of phosphorus components in the sediments of Haihe Basin by 31P-NMR and SMT|
|Place of Conferral||北京|
|Keyword||磷形态 沉积物 海河流域 Smt法 液相 31p-nmr Phosphorus Compounds Sediments Haihe Basin Smt 31p-nmr|
本文选择 SMT方法和液相 31P-NMR技术研究了海河流域主要河流和湿地沉积物中磷形态特征。SMT法通过使用不同性质的酸碱提取剂将沉积物磷分为无机磷（IP），有机磷（OP），NaOH提取态磷（NaOH-P），HCl提取态磷（HCl-P）及总磷（TP），较好地将无机磷分为了较易释放的 NaOH-P以及稳定的 HCl-P，而SMT法只能得到有机磷总量，无法深入的认识有机磷。因此同时选择本组构建的适合于富含 Fe/Al的沉积物的有机磷液相31P-NMR分析方法测定沉积物中有机磷含量，这一方法具有提取效率高、稳定且图谱质量较好的优势，可以测定沉积物中不同有机磷化合物含量。本文利用这两种方法，分别对海河流域主要滨海湿地、主要入海河流沉积物的磷形态特征及其转化特征进行了探讨；为了进一步研究海河流域典型河流人工河流沉积物中磷形态特征，选择了永定河、永定新河以及子牙河、子牙新河对比分析了其磷形态空间分布特征，并对子牙新河沉积物中磷的沉积特征进行了深入的研究。通过系统的研究，不仅揭示了海河流域主要滨海湿地、入海河流沉积物的磷组成及含量特征，而且探讨了海河流域特有人工河流沉积物中磷形态分布及沉积特征，为海河流域河流富营养化治理提供了理论依据。研究结果表明：
（1）HCl-TP和EDTA-TP相关性显著，且回收率稳定在 50%以上，表明SMT分级方法和改进的液相31P-NMR分析方法都是科学有效的。沉积物中总共有六种磷化合物通过液相 31P-NMR被检测出来，正磷酸盐和磷酸单酯分别是沉积物中总磷和有机磷的主要组成成分，焦磷酸盐、DNA-P、磷脂、膦酸盐和多聚磷酸盐含量较低。
（2）湿地土壤中的磷主要是无机磷，且主要是不易释放的 HCl-P，较易释放的 NaOH-P比例只有 5%~22%，释放风险较小。有机磷的主要组分是磷酸单酯，且南部湿地土壤中有机磷含量明显高于北部湿地，在南部湿地发现含量较基于 SMT方法及液相31P-NMR技术的海河流域主要湿地、河流沉积物磷形态特征研究高的 DNA磷，说明其微生物活性较高。除此之外，在受到水产养殖污染的湿地，其有机磷含量会相对偏高，造成磷累积。
（5）子牙新河沉积物中 TC、TN、TS、TP含量的垂向变化趋势基本一致，表层含量高，中上部出现一个速降层，而后逐渐波动降低，说明沉积物中的磷存在着表层富集的现象，大量污染物受沉积作用累积于上层。HCl-P所占比例随深度的增加有增加的趋势，NaOH-P与 HCl-P的变化趋势相反，随深度的增加而降低，OP所占TP比例最小，变化趋势和NaOH-P相似。随着沉积柱深度的增加，磷的种类和含量都逐步降低，子牙新河中下游样点总磷含量较高，且降低速率要明显大于中上游样点。中下游河段河流沉积物中有机磷含量呈现迅速的降低趋势，且表层沉积物磷含量可以达到 20 cm深度磷含量的十倍左右，反映了表层沉积物磷污染的严重性以及沉积物中磷释放的危险性。
|Other Abstract|| With the rapid growth of the world population and economy, the growing pollution problem caused the continued deterioration of the water quality, and water environment has become a global environmental problem. China is currently in a period of rapid economic growth, and eutrophication is one of the major pollution problems our country faced. As the Haihe River Basin has the special location, its cities and industries were intensive and large amounts of nitrogen, phosphorus, and other chemical ozone-depleting substances were discharged into the rivers, causing part of the water and sediments quality of rivers, wetlands in eutrophic state, and thus brought serious environmental problems to the Bohai Sea such as red tide.|
This paper studied different phosphorus components in the sediments of main rivers and wetlands in the Haihe Basin by using SMT and 31P-NMR methods. SMT is a sequential extraction procedure using different extraction agents HCl and NaOH,and sediment phosphorus can be divided into inorganic phosphorus (IP), organic phosphorus (OP), NaOH-P, HCl-P and TP. However, SMT method only get the total organic phosphorus, and unable to understand organic phosphorus thoroughly. So we selected the 31P-NMR analysis suitable for Fe/Al-rich sediment to measure the content of different organic phosphorus compounds in sediments. 31P-NMR is a non-destructive, non-invasive technique for identifying chemical forms and can analysis OP component completely, Therefore, it is an ideal technique for use in analysis of OP species in marine or freshwater sediment.
In this paper, we identified the phosphorus components distribution and transformation characters of the major coastal wetlands and rivers respectively in the Haihe River Basin. In order to further study the unique phosphorus distribution characteristics of the artificial river, we selected the Yongding River, Yongdingxin River and Ziya River, Ziyaxin River to analysis the phosphorus characteristics in comparison; what’s more, vertical change trends of phosphorus fractions in Ziyaxin River sediment was studied thoroughly. In all, we not only revealed the content and distribution characteristics of phosphorus composition of major coastal wetlands and rivers in the Haihe River Basin, but also explored the unique characteristics and vertical change trends of phosphorus fractions in artificial river sediments in the Haihe River Basin, thus provided the theory basis for internal control for eutrophication of the Haihe River Basin.
The main contents and detail results are as follows:
(1) HCl-TP and EDTA-TP were significantly correlated, and the recovery was stable above 50%, indicating that SMT classification method and the improved 31P-NMR methods were scientifically valid, and can reflect the actual content of the samples. Six phosphorus compounds were detected by 31P-NMR, orthophosphate and phosphate monoesters were the main components of the total phosphorus and organic phosphorus in the sediments, what’s more, pyrophosphate, DNA-P, phospholipids , phosphonates and polyphosphates content were relatively low.
(2) The phosphorus in the wetlands soil was mainly inorganic phosphorus, and most of it were HCl-P, the proportion of easy released NaOH-P was only 5% to 22%,thus had little risk of release. The main component of the organic phosphorus is phosphate monoester, and the phosphate monoester content in the southern wetlands was higher than it in the northern wetlands; DNA-P presented in most of the southern wetlands, indicating that microbial activity was higher in the southern wetlands. In addition, the wetlands subjected of aquaculture pollution, had relatively high content of organic phosphorus, resulting in the accumulation of phosphorus.
(3) Due to heavy pollution in the Haihe River Basin, three rivers in it, including Luan River, Yongdingxin River and Ziya River, all had high content of phosphorus,organic phosphorus and orthophosphate, thus had a high risk of release. TP content along the river flows tended to decrease, and HCl-P content in the estuary was relatively high.
(4) The artificial river Ziyaxin River and Yongdingxin River had a significantly higher content of phosphorus, orthophosphate, pyrophosphate, phosphate monoester,and DNA-P than the natural river Ziya River and Yongding River. Arificial rivers had small degree of meandering, simple riparian zone, small slope, and many dams, so their physical continuity were poor, and had weak self-purification capacities.Therefore, the phosphorus content in sediments of artificial rivers were relatively high, and had a high state of eutrophication.
(5) The vertical trends of the content of TC, TN, TS, TP were similar, and the content in the surface were highest, then decreased rapidly, and then gradually reduced. It indicated that the phosphorus enriched in the surface sediments, and large quantities of pollutants accumulated in the upper layers. HCl-P proportion increased with the depth, and decreased quickly in the first 10 cm; while NaOH-P had a opposite variation trend with the HCl-P, and it decreased with the depth; OP shared smallest proportion of TP, and had a similar trend with the NaOH-P.
With the increased depth of the column, the types and contents of phosphorus are gradually reduced. The phosphorus content in the middle and downstream of the Ziyaxin River were significantly higher than the upstream samples. Organic phosphorus content in the middle and lower reaches of the river sediment showed a quickly decreasing trend, and the phosphorus content in the surface sediments was ten times than it in the depth of 20 cm around, it indicated the seriousness of phosphorus pollution in surface sediments, and suggested the high release risk of phosphorus in sediments
|李洁. 基于液相31P-NMR技术与SMT方法的海河流域主要湿 地、河流沉积物中磷形态特征研究[D]. 北京. 中国科学院研究生院,2015.|
|Files in This Item:|
|李洁--基于液相31P-NMR技术与SM（5311KB）||学位论文||开放获取||CC BY-NC-SA||Application Full Text|
|Recommend this item|
|Export to Endnote|
|Similar articles in Google Scholar|
|Similar articles in Baidu academic|
|Similar articles in Bing Scholar|
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.