Study on the forms of nitrogen in the sediments from the Zhejiang offshore

本文应用分级浸取法对浙江近岸海域表层和柱状沉积物中氮的赋存形态研究，探讨了不同形态氮的生物地球化学行为。得到的主要结论包括： 1.浙江近岸海域表层沉积物中，四种形态氮与沉积物的结合强弱顺序为IEF-N＜CF-N＜IMOF-N＜OSF-N，含量大小顺序为OSF-N＞IMOF-N＞IEF-N＞CF-N。各形态氮在时间尺度上对氮循环的绝对贡献大小与其在沉积物中的含量大小相同。 2.对沉积物中影响各种形态氮分布的环境因素的分析表明，沉积物粒度和有机碳含量对不同形态氮的影响较显著；上覆水温度、盐度和NO3-影响IEF-N和OSF-N分布；DO含量是影响OSF-N形成和释放的显著因素；Cu、Pb、Cr...Based on the sequential extract processes, the different forms of nitrogen in the surface and core sediments of Zhejiang offshore and their functions in nitrogen biogeochemical cycling are studied in this thesis. The major conclusions are as follows: 1. The degrees of the four nitrogen forms linking with sediments are different. The sequence is IEF-N＜CF-N＜IMOF-N＜OSF-N, and the sequence of the co...学位：理学硕士院系专业：海洋与环境学院海洋学系_海洋化学学号：2242007115085

Effects of colloid sources and concentrations of colloidal organic carbon on the growth of colloids' own nature bacteria community

利用错流超滤技术分离厦门湾东南部海域、九龙江河口及九龙江水体中的胶体,并利用实验室模拟培养实验研究了胶体的来源和胶体有机碳(COC)浓度对其自身菌群生长的影响.结果表明,不同来源的3种胶体对自身菌群均有不同程度的促进作用,而且其依序为海洋胶体>河口胶体>河流胶体.海洋胶体和河口胶体中自身菌群的相对增长率的平均值y1、y2与CCOC之间呈正相关关系;而河流胶体中自身菌群的平均相对增长率y3与CCOC却呈负相关关系.Colloids were abstracted by cross-flow ultrafiltration technique from Xiamen Bay,Jiulongjiang Estuary and Jiulongjiang River,respectively.The effects of colloids with different sources and different concentrations of colloidal organic carbon(COC)on the growth of colloids' own nature bacteria community were studies.The results showed that the relative increasing rate(Y) of colloids' own nature bacteria community were 44.9%～133.0%,101.1%～210.9% and 47.5%～98.5%,respectively.The average relative increasing rate(Y) were 91.6%,150.9% and 72.8%,respectively.The maximum growth stimulations of colloids' own nature bacteria community for 3 colloids were riverine colloids,marine colloids and estuarine colloids in descending order.The results show that there were positive correlations between the average relative increasing rate(Y) and the concentrations of colloidal organic carbon(COC) for estuarine colloids' own nature bacteria community and for marine colloids' own nature bacteria community.However,the average of relative increasing rate(Y) of the riverine colloids' own nature bacteria community was negatively correlated with the concentrations of colloidal organic carbon(COC).国家教育部高等学校骨干教师计划基金资助项目;国家自然科学基金重大研究计划重大项目(904111016

Geochemical characteristics of nitrogen in the core sediments from Changjiang River Estuary

研究分析了长江口柱状沉积物中氮的赋存形态,并结合沉积速率和有机碳含量分析了氮的迁移转化特征和有机质来源。研究结果表明,有机物与硫化物结合态氮(OSf-n)是柱状样可转化形态氮中的主要赋存形态,碳酸盐结合态氮(Cf-n)含量最低;位于长江口122°E附近测点的各形态氮的垂直分布与122.6°E附近测点的差异明显,受水动力条件和沉积速率等因素影响,122.6°E附近测点的有机氮降解速率常数和各形态氮的埋藏通量均高于122°E附近测点;长江口柱状沉积物中有机氮降解主要发生在沉积物表层和次表层;OC/Tn值的垂直分布变化幅度较大,陆源输入均大于70%。Total nitrogen and its forms in the core sediments from Changjiang River Estuary were studied with sequential extraction method.And combined with the deposition rate and the organic carbon content,the characteristics of its migration and transformation and the sources of organic carbon were also studied.The results show that OSF-N is the main form of transferable nitrogen,and CF-N content is the lowest of the transferable nitrogen in the core sediments.There are evident differences in the vertical distribution of different nitrogen forms in the core sediments of SH3111 station(at 31°N,122°E) from that in SH3110 station(31°N,122.6°E).Affected by the hydrodynamics and the deposition rate,the values of the degradation rate constant of the organic nitrogen and the burial flux of different forms of nitrogen at the SH3110 station are higher than those at the SH3111 station.Degradation of the organic nitrogen occurred mainly in the surface and sub-surface layers of the sediment and the vertical distribution of the OC/TN ratios varies greatly,showing different depositional conditions.The proportions of terrigenous carbon are higher than 70%.环保公益性行业科研专项资助项目(2008467041);浙江省环保厅科研专项资助项目(2008-30

Nitrogen forms and their concentration distribution in surface sediments of Zhejiang offshore

运用分相浸取法分析了浙江近岸海域60个站位的表层沉积物(0~2 CM)中各形态氮的含量和分布.研究结果表明,表层沉积物中总氮(Tn)含量为214.66~861.44 Mg/kg,均值为580.52Mg/kg,位于浅水区的长江口、杭州湾和浙江沿岸的Tn含量低于东部远岸海域;可转化态氮(TTn)含量只占总氮的3.06%~37.24%,有机态和硫化物结合态氮(OSf-n)是沉积物中可转化态氮的主要赋存形态,非转化态氮(nTn)是浙江近岸海域表层沉积物中的优势形态.各站位沉积物中氮在不同提取相中的含量差异较大,与沉积物的陆源输入、沉积物重金属含量、粒径分布及沉积海域的水动力条件等因素有关.Different forms of nitrogen in surface sediments of Zhejiang offshore were studied with sequential extraction method.The result show that total nitrogen concentration in offshore surface sediments of Zhejiang ranged from 214.66 to 861.44 mg/kg with an average 580.52 mg/kg,and the concentration of TN was found higher in the eastern offshore of Zhejiang than Changjiang Estuary,Hangzhou Bay and Zhejiang coastal area.Transferable nitrogen,accounting for least part of total nitrogen,varied from 3.06% to 37.24%.Organic matter-sulfide form(OSF) is the dominant form of transferable nitrogen while non-transferable form is the dominant form in the surface sediments.Distribution of nitrogen forms is controlled by environmental factors,such as terrigenous inputs,grain size,heavy metal contents in surface sediments and hydro-dynamics.国家环保部公益科研专项资助项目(2008467041);浙江省环保厅科研专项资助项目(2008-30

干旱区土地退化监测预警与防治示范

本项目以综合生态系统管理理念为理论指导,创建量化的新疆土地退化监测与评价指标体系、新疆综合生态系统管理信息系统和预警系统,优选出土地退化防治模式,对伊犁河流域的土地退化进行宏观评价。经过6年时间,完成或超额完成了项目任务书拟定的目标和任务,解决了关键技术问题。 主要技术性能指标： 1.新疆土地退化监测与评价指标体系成果报告,提供伊犁河流域土地退化评价状况报告,形成伊犁河流域土地退化评价图(1：100万); 2.建立新疆土地退化(土地荒漠化及土地沙化)管理信息系统(两套),土地退化管理信息系统的应用软件,可推广到西部六省区应用; 3.建立完整的新疆不同土地..