Elemental composition in the sediments of the Yangtze and the Yellow Rivers and their tracing implication

Elemental compositions in the surface sediments of the Yangtze River and the Yellow River are quite different. The Yangtze River' s sediment is rich in K, Fe, Mg, Al and most of trace elements, and its elemental composition show remarkable spatial variations, whereas the Yellow River s sediment has higher contents of Ca, Na, Sr, Ba, Zr and Hf, and the elemental composition remains relatively stable. The ratios of some elements are also different in the sediments of the two rivers. The elemental composition of the Yangtze River sediment results from widely distributed igneous rocks and complicated source rocks and strong chemical weathering in the Yangtze River catchment basin, while the main provenance of the Yellow River sediment is the Loess Plateau which has dominant influence on the elemental composition, and the intense physical weathering is another controlling factor. The elements such as Cu, Zn, Sc, Ti, Fe, V, Ni, Cr, Co, Li and element ratios such as La/Sc, La/Co, Th/Co, Ti/Zr and Zr/Y can be used as the tracers to distinguish the Yangtze River sediment from the Yellow River s. The tracers can be used in the study of the mixing and distribution of the substances of the two rivers matters in coastal zones of China.     

Analysis on River Sediment Changes of the Upper Reaches of Yangtze River

The sediment load and river sedimentation of the upper reaches of Yangtze River has been undergoing constant changes as complex landformlarge mountain area and plentiful precipitation make the drainage area of Yangtze River very vulnerable to water erosion and gravity erosion. Through analyzing the hydrological and sediment load statistics recorded by major hydrological stations along Yangtze River since 1950s, and editing the accumulation graph of annual runoff volume and annual sediment load, we find out that the suspended-sediment of Yangtze river has been decreasing year by year in Wulong Hydrological Station on Wujiang River, Beibei Hydrological Station on Jialingjiang River, Lijiawan Hydrological Station on Tuojiang River and Gaochang Hydrological Station on Minjiang River, Yichang Hydrological Station, Cuntan Hydrological Station along Yangtze River mainstream share the same experience too. But the statistics obtained at Pingshan Hydrological Station on Jinshajiang River shows the sediment load there has increased. Taking ecological construction, hydraulic engineering construction and precipitation changes into consideration, the thesis analyses the cauls for the sediment load decrease of Jialingjiang River, Tuojiang River, Minjiang River and Wujiang River and provides us both scientific foundation for further study of river sediment changes of the upper reaches of Yangtze River, and measures to control river sedimentation.     

基于自组织竞争网络的黄河和长江物源判别

利用黄河和长江在地质历史时期的沉积物与现代黄河长江沉积物应具有一定的相似性这一原理,＂将今论古＂,以现代黄河和长江入海沉积物中部分常量元素的百分含量作为基准数据建立自组织竞争网络,对来自不同时代的黄河和长江的沉积物进行判别和验证,可靠性达到94.4%,并规定了其相应置信度下的置信区间.以此为基础,对南黄海NT2孔的物质来源进行了判别,结果表明钻孔中0～19.36m、28.07～52.88m深度范围内的沉积物为长江沉积物,19.36～28.07m、52.88～70.28m深度范围内以及表层沉积物为黄河沉积物.     

黄河下游高含沙洪水冲淤特性及其调控对策初探

基于黄河下游实测资料,对高含沙洪水对下游各河段河槽淤积的影响进行了分析,认为来自河口镇至龙门区间的高含沙洪水是造成下游高村以上河段河槽淤积的主要原因,高村以下河段的汛期河槽淤积物甚至全部来自高含沙 洪水.降低含沙量、增大流量和提高细沙比例至70%～80%以上可显著减轻高含沙洪水对河槽的淤积,而这可通过调控水库排沙比来实现.进一步分析了水库排沙比与出库泥沙的含沙量与细沙比例的关系,建议小浪底水库对高含沙洪水的调控要控制其排沙比在50%.在河龙问粗泥沙集中来源区,由于其来水很少、来沙很多,可利用该区"沙随水来"的特点使河龙间洪水就地利用,以减少黄河高含沙洪水产生几率和入黄泥沙量.     

Analysis on river sediment changes of the upper reaches of Yantze River

The sediment load and river sedimentation of the upper reaches of Yangtze River has been undergoing constant changes as complex landform, large mountain area and plentiful precipitation make the drainage area of Yangtze River very vulnerable to water erosion and gravity erosion. Through analyzing the hydrological and sediment load statistics recorded by major hydrological stations along Yangtze River since 1950s, and editing the accumulation graph of annual runoff volume and annual sediment load, we find out that the suspended-sediment of Yangtze river has been decreasing year by year in Wulong Hydrological Station on Wujiang River. Beibei Hydrological Station on Jialingjiang River, Lijiawan Hydrological Station on Tuojiang River and Gaochang Hydrological Station on Minjiang River, Yichang Hydrological Station, Cuntan Hydrological Station along Yangtze River mainstream share the same experience too. But the statistics obtained at Pingshan Hydrological Station on Jinshajiang River shows the sediment load there has increased. Taking ecological construction, hydraulic engineering construction and precipitation changes into consideration, the thesis analyses the causes for the sediment load decrease of Jialingjiang River, Tuojiang River, Minjiang River and Wujiang River and provides us both scientific foundation for further study of river sediment changes of the upper reaches of Yangtze River, and measures to control river sedimentation. Foundation item: Supported by the National Natural Science Foundation of China (50099620) Biography: ZHONG Xiang-hao (1942-), male, researcher, research direction: mountain environment and ecology.     

黄河下游高含沙洪水冲淤特性及其调控对策初探

基于黄河下游实测资料,对高含沙洪水对下游各河段河槽淤积的影响进行了分析,认为来自河口镇至龙门区间的高含沙洪水是造成下游高村以上河段河槽淤积的主要原因,高村以下河段的汛期河槽淤积物甚至全部来自高含沙洪水.降低含沙量、增大流量和提高细沙比例至70%~80%以上均可显著减轻高含沙洪水对河槽的淤积,而这可通过调控水库排沙比来实现.进一步分析了水库排沙比与出库泥沙的含沙量与细沙比例的关系,建议小浪底水库对高含沙洪水的调控要控制其排沙比在50%.在河龙间粗泥沙集中来源区,由于其来水很少、来沙很多,可利用该区"沙随水来"的特点使河龙间洪水就地利用,以减少黄河高含沙洪水产生几率和入黄泥沙量.     

珠江入海泥沙的浓度和成分特征及其沉积扩散趋势

分析了珠江入海泥沙浓度的时空分布及成分特性,探讨了3种动力因素作用下泥沙搬运、沉积、扩散的范围和去向,指出河口海区是珠江入海泥沙沉积的良好环境,雷东环流地区为其向西南扩散、沉积的终极场所。     

长三角小流域AnnAGNPS模型参数敏感性及适用性评价

【目的】研究年度农业非点源污染模型(Annualized agricultural non-point source pollutant loading model,AnnAGNPS)在沛桥河小流域的参数敏感性与适用性,为长三角地区的流域综合管理工作提供数据支撑和科学依据。【方法】以长江中下游水阳江水系沛桥河小流域为研究区,采用差分灵敏度分析(differential sensitivity analysis,DSA)方法进行参数敏感性分析,通过相关系数(R²)、效率系数(E)以及相对误差(E_R)来综合评价模型的适用性。【结果】对研究区径流、总氮与总磷输出模拟最敏感的参数是径流曲线数(CN),对泥沙输出模拟敏感性程度最高的参数是CN、土壤可蚀性因子(K)、水土保持因子(P)与作物管理因子(C),且均呈正相关影响特征。验证期(2015—2018年)汛期与非汛期径流、泥沙、总氮与总磷的相关系数(R²)、效率系数(E)均大于0.80,相对误差(E_R)的绝对值均小于12%;模型对径流与泥沙汛期的模拟精度均高于非汛期,而对总氮与总磷负荷非汛期的模拟精度略高于汛期。【结论】校准后的AnnAGNPS模型应用于沛桥河小流域的模拟效果较好,可用于辅助长三角低山丘陵区农业小流域非点源污染与水土流失管理决策。     

治理黄河泥沙的新途径——小北干流放淤

介绍了黄河泥沙的主要来源及危害,提出了治理黄河泥沙的新举措——小北干流放淤,分析了小北干流放淤的客观性和必要性,指出了小北干流放淤对黄河治理的长远影响。     

人类活动对长江泥沙特性的影响

随着长江流域水资源开发利用程度的提高,长江泥沙特性在一定程度上也发生了变化.为分析水资源开发利用对长江泥沙特性的影响,以长江万县、宜昌、汉口、大通、白河、仙桃6个水文站为研究对象,以丹江口、葛洲坝及三峡水库关闸蓄水时间划分研究阶段,利用各站近50 a的日含沙量资料对比分析了各研究阶段长江年、汛期、非汛期、月输沙量变化特性.结果表明,不同历时的输沙量均呈显著减少趋势.该研究成果为评价人类活动对长江生态系统健康与稳定性的影响提供了参考.     

深圳市大沙河底泥毒物污染特征及对策探讨

运用生物毒性监测方法，对深圳市南山区大沙河底泥毒物污染特征进行了分析，结果表明，大沙河底泥不同程度的受到了毒物污染，底泥毒物污染趋势与水体毒物污染趋势基本一致；还结合化学监测方法，分析了大沙河底泥毒物主要为有机毒物．此外，就大沙河底泥毒物的治理方法提出了自己的见解．     

黄河调水调沙实践

黄河水少沙多,水沙不协调．通过水库联合调度、泥沙扰动和引水控制等手段塑造协调的水沙关系,有利于下游河道减淤甚至冲刷．开展全程原型观测和分析研究,检验调水调沙调控指标的合理性,进一步优化水库调控指标,探索调水调沙生产运用模式,为黄河下游防洪减淤和小浪底水库运行方式提供重要参数和依据．2002-2007年,黄河水利委员会进行了3次黄河调水调沙原型试验和4次调水调沙生产运行,效果显著,成果丰富,取得了巨大社会效益和经济效益．     

长江输沙与河口的冲淤变化关系

以长江宜昌站、汉口站和大通站的径流量、输沙量等水沙特征值以及在崇明东滩上的实测数据为资料来源,探讨了多年来长江口的来水来沙态势,并运用泥沙通量估算方法,推算出近年崇明东滩的年淤涨速度,通过对比发现：近年来长江的径流量未见减少,输沙量却有减少的趋势;潮滩向海淤涨明显减慢．作者对两者之间存在的关系及其原因作了初步探讨,认为潮滩淤涨减慢在很大程度上是由于长江的输沙量减少所致;淤涨减慢的幅度超过了来沙量减少的程度,其重要原因是上游来沙减少的主要是易于沉积的中粗颗粒部分．     

Magnetism parameters characteristics of drilling deposits in Jianghan Plain and indication for forming of the Yangtze River Three Gorges

The forming time of the Yangtze River Three Gorges is considered as one of keys in the research on the Yangtze River, also is one of the most disputed hotspots. In order to solve the difficult problem, the authors adopt the internationally recognized thoughts and methods of substance tracing from source to sink. The lithologic characteristics, magnetic parameters and magnetic mineral characteristics of deposits in 2 bores are analyzed, which are both sampled from the sedimentary center of the Jianghan Plain. The results are as follows： At about 110 m depth of the core, the contents of coarse materials and stable magnetic mineral both increase significantly. Meanwhile, the magnetic susceptibility of sediment, saturation isothermal remanent magnetization and magnetic susceptibility values of anhysteretic remanent magnetism increase suddenly, which all reflect that at about 110 m depth, the important adjustment has appeared in water system of the Jianghan Plain, and the sedimentary environment and material composition have changed greatly. And it may be the horizon where the Yangtze River Three Gorges formed, its forming time reflected by the paleomagnetic dating is between 1.17 and 1.12Ma B.P.     

淮河干流典型污染物时空分布特性分析

针对目前淮河水环境现状及问题,2014—2017年先后7次采集淮河干流(正阳关—老子山)19个断面的上覆水样和沉积物泥样,对上覆水和沉积物中关键污染物指标总磷(TP)及主要重金属(As、Cu、Pb、Zn)含量进行分析,探究淮河干流TP和重金属时空分布特征与主要影响因素,并对各污染物的环境影响效应作出评价。结果表明:11月各污染物含量明显低于6月,水动力过程影响比较大;各污染物质量浓度整体呈现下降趋势,TP和As下降最明显;污染物来源分析显示,沉积物中TP主要受到面源污染影响,重金属污染物主要受点源污染影响;监测区间内淮河沉积物TP和4种重金属含量不具有生态风险。     

黄河沉积物对磷酸盐吸附的固体浓度效应研究

研究黄河沉积物对磷的吸附特征.用修改的Langmuir吸附模型将黄河沉积物对P的吸附数据进行有效拟合,通过吸附实验和模型计算得到描述黄河天然沉积物对P吸附特性的参数值.研究结果表明:黄河沉积物有向上覆水释放磷的倾向;沉积物对磷的吸附存在明显的固体浓度(Cs)效应,吸附滞后角随着Cs的增加而增大,在解吸过程中表现出一定的滞后性,即不可逆性.     

长江口冰后期沉积物的元素组成特征

长江口冰后期钻孔沉积物的元素地球化学研究表明,绝大多数无比民表层沉积物非常接近,反映冰后期沉积物主要来自长江,其它物源及环境变化影响较小,不同沉积环境中一些元素组成会发生变化,尤其是河床相沉积物中过渡金属元素组成化最明显,不同沉积相中稀土元素（ＲＥＥ）绝对质量比虽有差异,但稀土的配分模式很接近,同样反映出冰后期沉积物物质来源的单一。     

松花江吉林市江段江水中多环芳烃来源的研究

为研究松花江吉林市江段中多环芳烃来源,采集了松花江吉林市江段2013年5月(平水期)、2013年8月(丰水期)和2014年1月(枯水期)的江水、沉积物、废水、降尘、降水及地表径流样品,测定了其中16种多环芳烃的含量,利用主成分分析法对降水中多环芳烃的来源进行分析,同时计算松花江吉林市江段中多环芳烃的输入通量。结果表明:江水中多环芳烃来源较为广泛,不同水期江水中多环芳烃来源有一定的差别,但所有水期石油源和交通源均是江水中多环芳烃的主要来源,平水期和丰水期沉积物中PAHs的主要来源是燃烧源,其次是石油源。松花江吉林市江段的多环芳烃最主要是通过上游来水的方式进入到江水中,其它输入方式按输入通量由多到少依次为废水排放、降尘、降水、地表径流。     

南黄海如东近岸海域的沉积物特征与输运趋势

2003年在南黄海如东近岸海域获取了表层底质样397个,进行粒度分析,获取粒度参数．分析结果表明,如东近岸海域的表层沉积物以砂质粉砂和粉砂质砂为主,其物源主要是古长江残留物质,受现代水动力作用改造并掺混一定数量的现代长江入海物质和江苏沿岸侵蚀的物质．采用粒径趋势进行分析,发现该海域深槽中的沉积物主要向外海输运,但在中部海洋沙、太阳沙以西存在一个沉积物汇聚中心．     

湘江四环素及抗性基因含量特征及其季节变化

采用高效液相色谱质谱法分析了湘江长沙河段水体及底泥中4种常见四环素类抗生素的含量特征及其季节变化,并采用实时荧光定量PCR研究了该水域相应的5种代表性抗生素抗性基因(tet A,tet C,tet G,tet M和tet X)的存在及丰度.结果表明,水体中四环素类抗生素的质量浓度均值在16.23~496.73ng·L-1之间,底泥中四环素类抗生素的质量分数为347.77~3 829.75ng·kg-1,易受季节变化影响.5种目标抗性基因在所有样品中均有检出,其中tet A和tet C的绝对拷贝数及相对丰度较高,为湘江长沙河段的优势抗性基因.相关性分析表明:冬季水体中的tet A和tet C含量与底泥中的含量显著相关,几种目标抗生素与抗性基因之间并不存在明显线性关系.