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1.
研究了胶体磷在河口海区随盐度变化的趋势,并将其与颗粒态、真溶解态磷随盐度的变化趋势进行对比,分析胶体态磷在河口的行为与颗粒态磷和真溶解态磷二者的异同.探讨磷在颗粒相,胶体相和真溶液相之间的分配及其与悬浮颗粒物浓度的关系,研究胶体磷在河口海区中的迁移转化作用.研究结果表明,胶体相中总磷、有机磷和活性磷浓度由河端向海端降低,表明陆源输入是其主要来源.胶体有机磷占总磷比例随盐度增加而下降,表明有机磷受胶体去除过程的影响较明显,胶体磷在河口海区的浓度变化趋势及胶体中有机磷和活性磷的比例都与真溶解相接近而与颗粒相差别较大.  相似文献   

2.
长江口夏季水体磷的形态分布特征及影响因素   总被引:2,自引:0,他引:2  
根据2006年7月至9月"海监49号"科学考察船夏季航次的调查数据,分析了长江口及邻近海域水体中磷形态的平面分布特征及其影响因素,结果表明,调查海域水体各种形态磷平均浓度均为底层高于表层,并呈现出由河口向邻近海域降低的趋势.杭州湾及最大混浊带部分区域水体中以颗粒态磷为主,且颗粒态无机磷为磷的主要存在形态;长江口门及江苏东部近海区域水体中以溶解态磷为主,溶解态无机磷为磷的主要存在形态;舟山群岛东部外海区表层水体以溶解态磷为主,溶解态有机磷为磷的主要存在形态,而底层水体中溶解态磷浓度略高于颗粒态磷,以溶解态无机磷为磷的主要存在形态.水体中颗粒态无机磷与颗粒态有机磷、颗粒总磷与总磷、总磷与悬浮颗粒物均呈非常显著的正相关,说明悬浮颗粒物是颗粒态磷的主要影响因素.调查海域外海区域绝大部分站位水体中溶解态无机磷表层浓度接近或小于浮游植物生长限制的动力学最低阈值,是磷限制或潜在的磷限制区域.  相似文献   

3.
1987年3月至1988年12月笔者在九龙江口、厦门西海域调查了颗粒态磷(PP)、溶解无机磷(DIP)、溶解有机磷(DOP)、总磷(TP)及其他水化学要素。研究结果表明,九龙江水携带入海的磷大部分以颗粒态存在,DOP占有相当的比例。各种形态磷的分布有明显的区域性差异。在河水海水混合过程中,PP发生明显转移,在S=15~20水域,达最低值。悬浮颗粒物上吸附的磷在盐度增大时解吸是DIP随S增大而增大的主要原因。该海区生物必需的磷主要不是来自九龙江水的供给,而是从海区磷的再生、转化中得到补充。  相似文献   

4.
1987年3月至1988年12月笔者在九龙江口、厦门西海域调查了颗粒态磷(PP)、溶解无机磷(DIP)、溶解有机磷(DOP)、总磷(TP)及其他水化学要素.研究结果表明,九龙江水携带入海的磷大部分以颗粒态存在,DOP占有相当的比例.各种形态磷的分布有明显的区域性差异.在河水海水混合过程中,PP发生明显转移,在S=15~20水域,达最低值.悬浮颗粒物上吸附的磷在盐度增大时解吸是DIP随S增大而增大的主要原因.该海区生物必需的磷主要不是来自九龙江水的供给,而是从海区磷的再生、转化中得到补充.  相似文献   

5.
利用切向超滤技术分离和提取九龙江口水体中溶解相(粒径0.45μm)、胶体相(分子量 1 k Da,粒径0.45μm)和真溶解相(分子量1 k Da)的活性磷酸盐(SRP)和溶解态总磷(DTP),初步探讨了不同相中各形态磷的环境化学行为。研究表明,切向超滤过程的SRP和DTP系统空白分别为ND~0.001 mg/dm~3和ND~0.005 mg/dm~3,均未高于方法检出限;样品质量回收率为92.3%~100.0%,满足80.0%~120.0%质量技术要求。真溶解相中SRP、溶解态有机磷(DOP)和DTP占溶解相比例为65.3%~92.3%,存在形式以真溶解相为主;胶体相中SRP、DOP和DTP的含量分别为0.13~4.19、3.25~19.20μg/dm~3和3.39~23.40μg/dm~3,占溶解相比例为1.2%~17.0%;真溶解相和溶解相中的各形态磷含量主要受陆源输入控制。  相似文献   

6.
九龙江口水体中1995年磷的转移   总被引:1,自引:0,他引:1  
1995年3个航次的调查研究结果表明,九龙江口水体总磷含量受悬浮物含量控制,在S<5的低盐度区,悬浮泥沙和磷产生明显的絮凝沉降,在S>5时,它们的迁移接近于理想混合。溶解磷的河口转移与其在河流端的浓度密切相关。当河端浓度低时,磷略呈溶出现象;而河端浓度高时则接近于理想混合过程。估算得出九龙江河流总磷的平均入海通量为2.9×103t/a,其中溶解磷和颗粒磷各占一半左右。  相似文献   

7.
九龙江口海域中磷的化学形态分布   总被引:4,自引:0,他引:4  
根据1987年3月至1988年12月笔者在九龙江口,厦门西海域的调查研究资料,着重讨论颗粒态磷,溶解态无机磷,溶解态有机磷,总磷等各种形态磷的含量分布,季节变化,及其与叶绿素,总悬浮物量等其他要素的关系。  相似文献   

8.
北部湾北部沉积物中磷的地球化学行为研究   总被引:1,自引:0,他引:1  
对2006年7月北部湾北部海区调查过程中采集的表层沉积物运用SEDEX方法进行了系统的总磷及其磷赋存形态分析.把磷(P)分为6种赋存形态:弱吸附态(Ads-P)、铁结合态(Fe-P)、自生磷灰石及钙结合态(Ca-P)、碎屑态(De-P)、有机态(OPS)及硅酸盐态(SIF-P).结合上覆水的环境参数,讨论了磷的地球化学行为特征.研究表明,沉积物是上覆水体颗粒磷(PP)的汇,而不是上覆水体溶解态总磷(DTP)的源,沉积物中的P具有保守性;TPS、Fe-P和OPs具有亲大陆性;盐度(S)是影响Fe-P、OPS、SIF-P的含量变化的重要因子;Ca-P、De-P、SIF-P是沉积物中的"惰性磷",Ads-P、Fe-P、OPS为沉积物中的"活性磷";海区P的主要循环路径可以描述为:PP (←→)OPS→SIF-P →Fe-P→IPS.  相似文献   

9.
利用2008年秋季胶州湾两个航次的调查结果,对该海域营养盐等生源要素的分布特征进行了分析,并通过相关性分析及陆海同步调查数据对其来源做了初步探讨.结果表明,胶州湾秋季两个航次的叶绿素、营养盐、化学需氧量、温度、光照、盐度、溶解氧等各调查要素相应的平面分布趋势基本相同,除盐度和温度外均表现出由河口向离岸逐渐降低的趋势.秋季可能成为胶州湾浮游植物生长限制因子的要素与叶绿素 a 相关性强弱顺序如下(“**”和“*”分别代表置信水平 P=0.01和 P=0.05):活性磷酸盐:0.889(**)、溶解无机氮:0.724(**)、溶解有机氮:0.549(**)、溶解有机磷:0.523(**)、颗粒态氮:0.474(**)、温度:–0.696(**)、活性硅酸盐:0.410(*)、颗粒态磷:–0.191、浊度:–0.096.由相关性分析结果及陆海同步调查结果可初步得出与叶绿素 a 相关性较强的各要素来源如下:化学需氧量、盐度、溶解无机氮、活性磷酸盐、溶解有机氮、溶解有机磷具有明显的陆源输入特征,颗粒态氮以浮游植物新陈代谢产生为主.  相似文献   

10.
长江口及其邻近海域磷的分布变化特征   总被引:5,自引:0,他引:5       下载免费PDF全文
根据2004年4个航次的调查资料,研究了长江河口内及其临近海域磷酸盐和总磷的分布变化特征。结果表明,磷酸盐和总磷的浓度分布都是河口附近高,外海低,但其最大值不在河口内,而在口门外。河口内磷酸盐秋、冬季浓度高,春、夏季低;总磷夏、秋季浓度高,春季和冬季低。口门外磷酸盐和总磷浓度分布都是冬、夏季高,春、秋季低。磷酸盐夏季浓度变化大,分层明显,冬季变化小,垂直分布均匀。总磷春季表、底层浓度接近,其余季节表层都低于底层。通过磷酸盐和总磷与盐度、悬浮体的相关关系研究表明,磷酸盐在河口转移过程中,还受到生物活动、水体垂直对流以及缓冲作用等多种因素的影响。总磷在很大程度上受颗粒磷的控制。  相似文献   

11.
Study of colloidal phosphorus variation in estuary with salinity   总被引:1,自引:0,他引:1  
The variation of colloidal phosphorus with salinity in estuary was studied in this paper, which was compared with those of particle and truly dissolved phosphorus with the purpose of ˉnding out the similarities and di?erences between their behaviors in the estuary. Distribution patterns of phospho- rus in particle, colloidal and truly dissolved phase at di?erent salinities and their relationships with suspended particulate matter were also studied to understand the transformation and transporta- tion of colloidal phosphorus in estuarine area. The result showed that the concentrations of total colloidal phosphorus, organic colloidal phosphorus and inorganic colloidall phosphate all descended from river-end to sea-end, illustrating their terrigenous source. Ratios of organic to total colloidal phosphorus decreased with salinity's increment, indicating that organic phosphorus was in°uenced by scavenging process of colloid more signiˉcantly as compared with inorganic phosphate. Both of the phosphorus variation tendencies and the proportion between organic and inorganic phosphorus in colloidal phase was similar with that in truly dissolved phase while di?erent from that in particle phase.  相似文献   

12.
A series of experiments was conducted to evaluate the appropriateness of cross-flow ultrafiltration (CFUF) techniques for the determination of the phase speciation of monomethyl mercury (MeHg) in natural waters. Spiral-wound cartridge (Amicon S1Y1) and Miniplate (Amicon) were evaluated for their nominal molecular weight cut-offs of 1 and 10 kDa, respectively. The ultrafiltration behavior of standard macromolecules showed that the permeation of high molecular weight (HMW) organic macromolecules was not significant when a concentration factor (CF)>15 was used. The retention of low molecular weight (LMW) molecules was significant, especially at a low CF<5, suggesting that the use of a high CF (15) will minimize the retention of LMW molecules. Sorptive losses of MeHg in the solution phase to the 1 kDa membrane were negligible, but MeHg bound to HMW macromolecules was still retained (20%), even with a preconditioned membrane. The mass balance recovery of MeHg during ultrafiltration averaged 101±15% (n=7) and 105±14% (n=5) for the 1 and 10 kDa membranes, respectively. Sample storage over 24 h caused significant coagulation (47%) of the <10 kDa MeHg into the 10 kDa–0.45 μm colloidal or the particulate MeHg pool. The 1 kDa–0.45 μm colloidal MeHg in Galveston Bay and the Trinity River water samples accounted for 40–48% of the filter-passing MeHg, although the most abundant fraction (52–60%) of MeHg was the truly dissolved fraction (<1 kDa). The partition coefficient between the colloidal (1 kDa–0.45 μm) and truly dissolved MeHg (average log KC=5.2) was higher than the partition coefficient based on particle/filter-passing (average log KD=4.6) or particle/truly dissolved MeHg (average log KP=4.8), suggesting that MeHg has stronger affinity for natural colloids than macroparticulate materials (>0.45 μm).  相似文献   

13.
根据1992年12月(冬季)和1993年7月(夏季)对大鹏澳海域24h定点连续观测和夏季大面调查,统计了该海域各种形态磷的变化范围和平均含量;计算了各种形态磷分别占总磷(TP)和总溶解磷(TDP)的百分比;讨论了各种形态磷之间的相互关系;分析了影响TP和TDP分布的环境因素。  相似文献   

14.
利用切向超滤(cross-flow ultrafiltration)技术对海水中胶体有机碳(COC)和真溶解有机碳(UOC)进行了分离,并分别用高温燃烧法和紫外/过硫酸钾法对胶体有机碳和真溶解有机碳进行了测定。测定结果表明,切向超滤能定量分离海水中的胶体有机碳,高温燃烧法和紫外/过硫酸钾法对胶体有机碳和真溶解有机碳的测定结果没有明显的系统误差,表明这两种方法的氧化效率基本相同,胶体粒子的存在,对紫外/过硫酸钾法的氧化效率没有显着影响。  相似文献   

15.
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium ( 〈 0.4 μm) exis- ted in the low molecular mass fraction ( 〈 10 000 u), and the colloidal uranium-238 (10 000 u -0.4 μm) only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases ( 〉 0.4 μm), the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows: 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows : 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value (1.0). The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic  相似文献   

16.
溶解态磷在海洋微藻碱性磷酸酶活力变化中的调控作用   总被引:19,自引:2,他引:17  
在实验室批量培养条件下,测定了海洋微藻培养体系中碱性磷酸酶活力(APA)和各形态溶解磷的动态变化,分析了二者之间的关系.结果表明,在批量培养过程中,APA的动态变化呈"S"形曲线,各形态溶解磷在其变化过程中所起的调控作用不同,介质中溶解无机磷和小分子溶解有机磷的浓度是激发APA发生变化的主要调控因子,大分子溶解有机磷的浓度对APA的作用不明显,但APA的增大可加速微藻利用大分子溶解有机磷的速率.微藻的种类和丰度不影响APA的动态变化形式及其调控机理.  相似文献   

17.
The phase partitioning of 234Th between dissolved (<10-kiloDalton, kD), colloidal (10 kD—0.4 μm), and particulate (⩾0.5 μm) matter across a horizontal transect, from a coastal station to the deep Canada Basin, and a vertical profile in the deep Canada Basin of the western Arctic Ocean was investigated. Concentrations of suspended particulate matter (SPM), dissolved, colloidal and particulate organic carbon, particulate organic nitrogen and nutrients (silicate, phosphate and nitrate) were also measured to assess transport and scavenging processes.Total 234Th (colloidal+particulate+dissolved) indicated deficiencies relative to secular equilibrium with its parent, 238U in the upper 100 m, which suggests active scavenging of 234Th onto particle surfaces. In contrast, at depths >200 m, general equilibrium existed between total 234Th and 238U. The inventory of SPM and the specific activity of particulate 234Th in the Canada Basin was about an order of magnitude higher than the profile reported for the Alpha Ridge ice camp station. This higher concentration of SPM in the southwestern Canada Basin is likely derived from ice-rafted sedimentary particles. Inventories of nutrients, and dissolved organic carbon and nitrogen in the upper 100 m of the Canada Basin are comparable to the other estimates for the central Arctic Ocean. Comparison of the mass concentrations of colloidal and filter-retained particulate matter as well as the activity of 234Th in these phases indicates that only a very small component of the colloidal material is actively involved in Th scavenging. Lower values of the conditional partition coefficient between the colloidal and dissolved phase indicate that the Arctic colloids are less reactive than colloidal material from other regions. The conditional partition coefficient between the filter-retained and dissolved phases (Kf) is generally higher than that for other regions, which is attributed to the higher complexation capacity of glacio-marine sedimentary particles in these waters. The 234Th-derived export of POC for the shelf and deep Canada Basin ranges between 5.6 and 6.5 mmol m−2 d−1, and is in agreement with other estimates reported for the central Arctic Ocean and Beaufort Sea.  相似文献   

18.
夏季辽河口各形态营养盐的河口混合行为   总被引:6,自引:0,他引:6  
利用2009 年7 月对辽河口水域航次的调查结果, 对该水域营养盐的形态和分布特征进行了探讨,并对其主要控制过程进行了讨论。结果表明: 辽河口水域营养盐的变化范围较大。磷主要以磷酸盐的形式存在, 其余依次是颗粒态磷PP、溶解有机磷DOP, 三者含量相差不大; 氮主要以硝酸盐的形式存在, 其余依次是溶解有机氮DON、颗粒...  相似文献   

19.
Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UV irradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus determination methods presently. The compounds used for the phosphorus recovery test were categorized into three groups according to their chemical structure. It was found that low power UV irradiation can decompose P-O-C or P-C bonds efficiently but may be inefficient for P-O-P bonds. Heating-bath in acid condition is useful for decomposing P-O-P bonds. Using the continuous flow analysis system (Auto-analyzer Ⅱ), UV digestion and heating-bath, series experiments were carried out based on the above analysis. Eleven model compounds were employed for the phosphorus recovery test and the factors influencing the decomposition efficiency of dissolved compounds containing phosphorus were clarified. Finally, the optimal design for determination of dissolved total phosphorus in seawater based on the routine continuous flow analysis system was presented. For the organic mono-phosphate, the recovery is more than 90% and a recovery of 33%~51% was obtained for inorganic or organic polyphosphates. Up to now, this is the highest decomposition efficiency for dissolved phosphorus based on the continuous flow analysis system.  相似文献   

20.
在实验室内模拟研究了沙海蜇消亡过程中氮与磷的释放特征。模拟结果表明:沙海蜇消亡过程中向水体释放氮、磷可分为两个阶段,且氮的释放速率比磷高一个数量级。在沙海蜇消亡的初期阶段,水体中溶解态氮、磷和总氮、总磷的浓度迅速增高,氮可以达到其消亡过程中的最高浓度;在后期阶段,水体中溶解态氮和总氮的浓度不断下降,但水体中的磷在这一阶段达到消亡过程中的最高浓度碱性条件有利于氮的释放,酸性条件有利于磷的释放;盐度越高氮与磷的释放速率越小;温度对氮、磷的释放影响不大;水体中氮与磷含量越高,沙海蜇消亡的速度越慢,而且氮的浓度越高,氮与磷释放到水体中的速率就越慢。  相似文献   

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