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1.
基于2003—2018年中分辨率成像光谱仪(moderate-resolution imaging spectroradiometer,MODIS)卫星遥感影像资料,结合2018年春季、夏季和冬季大面站悬浮体取样分析结果,构建了表层悬浮体浓度遥感反演模型;在此基础上,分析了山东半岛东北部海域年际和月份表层悬浮体浓度时空分布规律,探讨了表层悬浮体浓度变化的主控因素和水体结构季节变化及其对悬浮体分布输运的影响。结果表明:山东半岛东北部海域表层悬浮体总体呈近岸高远岸低的分布特征,东部成山头区域悬浮体浓度较高且向海扩散较远,西部威海湾及外侧海域悬浮体浓度较低且扩散范围小于东部。研究区悬浮体浓度季节性变化显著但对应季节年度变化较小,冬季悬浮体浓度达到最大,春秋季次之,夏季最低。研究区春季、秋季和冬季表层悬浮体浓度主要受控于北向风浪和潮流,而夏季悬浮体浓度主要受潮流控制。夏季,温跃层阻碍了悬浮体垂向扩散,导致表层悬浮体浓度极低;冬季,研究区东部成山头附近水平分布的弱温跃层虽然会在一定程度上抑制悬浮体的再悬浮,但再悬浮扩散仍是造成研究区高悬浮体浓度的主要因素。山东半岛东北部存在类似"夏储冬输"的特征,海底沉积物再悬浮物质及成山头附近悬浮体的水平扩散是研究区悬浮体的主要来源。  相似文献   

2.
The data on the isotopic composition of particulate organic carbon (δ13CPOC) in the Caspian Sea water in summer–autumn 2008, 2010, 2012, and 2013 are discussed in the paper. These data allowed as to reveal the predominant genesis of organic carbon in suspended particulate matter of the active seawater layer (from 0 to 40 m). The δ13CPOC =–27‰ (PDB) and δ13CPOC =–20.5‰ (PDB) values were taken as the reference data for terrigenous and planktonogenic organic matter, respectively. Seasonal (early summer, late summer, and autumn) variations in the composition of suspended particulate matter in the active sea layer were revealed. A shift of δ13CPOC towards greater values was seen in autumn (with a slight outburst in the development (bloom) of phytoplankton) in comparison with summer (with large accumulations and an extraordinary phytoplankton bloom confined to the thermocline area). The seasonal dynamics of autochthonous and allochthonous components in the suspended particulate matter of the Middle and Southern Caspian Sea was studied with the use of data on the concentration of particulate matter and chlorophyll a, the phytoplankton biomass and the POC content.  相似文献   

3.
南黄海悬浮体浓度的平面分布特征及其输运规律   总被引：3，自引：1，他引：2  
重点分析和探讨了南黄海悬浮体浓度的平面分布及其水平输运,结果显示悬浮体浓度具有显著的空间区域化分布特征,其与该海域环流场的布局和季节转换存在良好的对应关系,南黄海环流是该海域悬浮体运移的主要动力和控制因素;江苏近岸海域在一年四季均为悬浮体浓度的最高值区,其悬浮体主要来源于潮流和海浪所引起的沉积物再悬浮以及苏北沿岸水的携带和输送,而且夏季悬浮体在该海域的累积还可为冬半年在黄海西部沿岸流作用下将其输运至东南海域提供很好的物源保证;长江口东北部海域在春、夏、秋三季出现东北向扩展的高值区,体现了长江冲淡水的影响;石岛外海在冬、春、秋三季也存在悬浮体浓度高值区,并具有向南黄海中部泥质区扩展的态势,这是鲁北沿岸流将现代黄河物质输运至此的结果。发现调查海域中部表底层在春秋季均存在云团状高值区,而且该海域悬浮体浓度自春季至秋季出现"双峰现象",这与春秋季水华期间浮游植物繁殖所产生的有机碎屑有关,并使作为悬浮体组成的海洋浮游生物有机质向沉积物转移,据此进一步指出这一物源可能对南黄海冷涡泥质区的形成、发育也具有一定的作用,该观点深化了对南黄海中部冷涡泥质区受上层生物活动影响以及泥质区物源的认识。  相似文献   

4.
常规异养细菌监测方法精度高但费时费力且不能连续观测, 而卫星遥感成本低、可以大面积同步、长时间周期观测, 可与常规方法互补。文章利用南海北部10个航次采集的表层异养细菌丰度和卫星遥感反射率, 采用统计回归的方法建立了异养细菌丰度的遥感模型, 其模型决定系数为0.81, 均方根误差为2.44×108个·L-1, 平均相对误差为21%, 具有较好表现。利用该模型估算南海北部表层异养细菌丰度, 结果显示: 从珠江河口到南海北部开阔海域, 异养细菌丰度逐渐减小。夏季河口地区平均异养细菌丰度最高, 春季最低; 近岸海域靠近珠江河口西侧的平均异养细菌丰度高于东侧; 冬季陆架地区平均异养细菌丰度最高, 夏季最低; 开阔海域的异养细菌丰度变化幅度较小。  相似文献   

5.
Particular features of the distribution of the transparency and particulate matter content, their variability, and their interdependence in the surface water layer (0–5 m) over the northwestern shelf and in the adjacent abyssal part of the Black Sea in the summer were considered on the basis of long-term simultaneous optical, biological, and hydrological observations (1979–1993). In the shelf regions with different river discharges and in the waters of the open part of the sea, the distributions of the transparency, the total particulate matter, and its organic components (organic carbon, nitrogen, and chlorophyll a), as well as the relative content of particulate organic carbon in the total amount of the particulate matter and the content of chlorophyll a in the particulate organic carbon, were considered. The distributions of the transparency and particulate matter and their dependence on the water dynamics are in good agreement. It was demonstrated that extreme anthropogenic eutrophication influences the western and northern coastal shelf areas. The water transparency and particulate organic matter distributions in the central shelf area subjected to the influence of transformed river water and the water properties of the southern part of the shelf, which is influenced by the waters of the open sea, were determined according to the particular structure of the phytoplankton, its abundance, and the processes of its production and destruction.  相似文献   

6.
《Marine Chemistry》2001,76(3):189-209
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7.
Studies of the dynamics of the concentration of the suspended particulate matter (SPM) and Corg in the seawater of Chupa Inlet were performed for the three-year period of 2010–2012. In general, the concentration of SPM increased from the spring through the summer, decreased through the autumn period, and declined dramatically in the winter. The ratio of the organic matter in the SPM decreased gradually from the surface water layer to the bottom and averaged 61%. The abiotic factors affecting the SPM concentration and suspended organic matter were studied; the water temperature and tide events were named as the liming ones.  相似文献   

8.
为了研究近岸海带养殖活动对水体光学特性的影响,本文选取山东半岛黑泥湾海域为典型研究区,利用2021年4月和8月在该区的9站同步观测数据,分析其总悬浮颗粒物、藻类颗粒物、非藻类颗粒物以及有色溶解有机物的吸收特性,并计算各组分对总吸收系数的贡献率,同时采用Quasi-analytical algorithm (QAA)算法借助MODIS影像反演了水体总吸收系数,结合实测数据获得了黑泥湾水体吸收特性的季节变化情况。结果表明,有海带养殖季节表层水体藻类颗粒物、非藻类颗粒物、总颗粒物和有色溶解有机物的吸收系数明显大于无海带养殖季节,且春季海带养殖区水体的总吸收系数大于无海带养殖区;海底表层沉积物的再悬浮造成底层吸收系数较大,而在春季成熟期的海带汇聚较大量的有机物质导致中层藻类颗粒物吸收系数相对较高;参考波长向红波移动,QAA_v5算法能够较好地估算该区表层水体吸收系数,且在海带养殖季节水体组分会影响到更长的波段特征。本研究可为深入了解海带养殖对水体各组分浓度和分布、碳循环以及水生生态系统的结构和功能的影响提供参照,并有助于提高近岸水体组分的遥感反演精度。  相似文献   

9.
The distribution of nepheloid layers across the outer shelf and upper continental slope off Namibia was studied during a cruise with R.V. Meteor in late austral summer 2003. Optical measurements, carried out with a transmissometer and a backscattering fluorometer, are correlated with suspended particulate matter (SPM) and particulate organic carbon (POC) values from water sample filtration. Conductivity-temperature-depth and oxygen data are used to relate the nepheloid layers to hydrographic structures. The particle content of surface water at the continental slope is controlled primarily by the offshore extension of highly productive upwelling filaments. A pronounced bottom nepheloid layer (BNL) covers the entire area of study with maximum intensity above the outer shelf and at the shelf break—an area where erosional forces dominate. The detachment of this BNL at the shelf break feeds a major intermediate nepheloid layer (INL) at 25.5°S. This INL is positioned at 250–400 m depth, at the lower boundary of an oxygen minimum zone, and is likely connected to the poleward flow of South Atlantic Central Water (SACW) across the shelf break. Together, these strong subsurface nepheloid layers are indicators of intensive lateral particle transport from the outer shelf towards a depocenter of organic matter on the upper continental slope.  相似文献   

10.
三峡截流后长江口秋季TSM、POC和PN的分布特征   总被引：2，自引：0，他引：2  
基于2004年11—12月长江口56个站位的悬浮体调查资料,分析了长江口区悬浮体总量(TSM)、颗粒有机碳(POC)和颗粒氮(PN)质量浓度的平面分布特征,探讨该区TSM及颗粒有机质的物质来源和三峡截流对长江三角洲的影响。结果表明,表、底层TSM与POC、PN质量浓度之间存在显著的正线性相关关系并都呈现出南高北低的格局,说明了长江悬浮颗粒物入海后主要沿东南方向输运。POC、PN质量分数与POC、PN的质量浓度不同,它们与TSM质量浓度对数有负相关关系。由于河口区底质再悬浮作用显著,TSM和POC、PN质量浓度呈现表层低、底层高的特点。长江口悬浮体主要来自长江径流和底质沉积物的再悬浮。与三峡截流前数据的对比表明,截流对目前长江口区的TSM和POC尚未造成明显的影响。  相似文献   

11.
利用2002—2015年的中等分辨率成像光谱仪(Moderate Resolution Imaging Spectroradiometer, MODIS)第4波段反射率产品对黄、东海边界的悬浮物输运情况进行了分析, 同时利用黄、东海2003年现场实测的悬浮物含量数据和这期间准实时的MODIS影像数据, 建立了基于MODIS第4波段遥感反射率的悬浮物含量遥感反演模型。基于该模型, 反演黄、东海表层悬浮物浓度, 并计算悬浮物扩散面积。利用反演得到的表层悬浮物浓度和悬浮物浓度垂向预测模型, 获取垂直方向上的悬浮物浓度, 同时结合水深、扩散面积数据, 计算特定时刻水体中的悬浮物含量。利用插值方法获得整个输运过程中各时刻水体中的悬浮物的含量, 计算各个时刻悬浮物含量的总和作为悬浮物的输送量。对2002年10月至2003年4月黄海向东海的悬浮输送量进行估算, 估算结果为153Mt。  相似文献   

12.
于2014年夏、秋两季在舟山海域进行了浮游植物拖网采集和环境理化因子测定,共鉴定浮游植物6门92属184种,其中硅藻门127种,甲藻门30种,为调查海域主要浮游植物类群。夏季骨条藻Skeletonema spp.为绝对优势种,秋季优势种由琼氏圆筛藻Coscinodiscus jonesianus、虹彩圆筛藻Coscinodiscus oculus-iridis、蛇目圆筛藻Coscinodiscus argus、星脐圆筛藻Coscinodiscus asteromphalus、骨条藻Skeletonema spp.、尖刺伪菱形藻Pseudo-nitzschia pungens、并基角毛藻Chaetoceros decipiens、伏氏海毛藻Thalassiothrix frauenfeldii及中间肋缝藻Frustulia interposita等9种硅藻构成。调查海域夏季浮游植物平均丰度(1 713.58×104个/m3)高于秋季(1 430.30×104个/m3)。冗余分析表明,温度、盐度、悬浮物、溶解无机磷及溶解无机氮等环境因子对夏、秋两季浮游植物群落影响较大。结合历史数据分析可知,舟山海域近30 a来富营养化程度严重且日益加剧,富营养化指数明显升高;同时浮游植物群落变化也十分显著,主要体现为细胞丰度增加和优势种更替。  相似文献   

13.
The results of the analysis of samples of the Northern Dvina River’s suspended particulate matter obtained by the sedimentation method from large water volumes in the periods of the spring high water and summer low water are presented. By the method of sequential leaching using different reagents, four fractions have been separated: the F1 is the sorbed complex and carbonates, the F2 is the amorphous hydroxides of Fe and Mn, the F3 is the form connected with the organic matter, and the F4 is the residual or silicate-detrital (inert) form. The data have shown that all ten elements determined were grouped with respect to the ratio of the distinguished forms: F4 is the predominant form for Al and Fe (73–88% of all the forms; however, the summer sample contains only 38% of this form of iron, and F2 is the predominant form for this period with 46.6%). As to Mn, the F1, F2, and F4 are nearly equally distributed in the spring high water samples, and only the F3 form is less important (5.4%). In the summer sample, the manganese sorbed complex is predominant (53.5%); for Cu, Ni, Cr, and Co, the inert F4 form is predominant (60–70%) in the sample of the spring suspended matter. The summer low water suspended matter has a lower F4 contribution (25–45%); for Zn, Pb, and Cd, the equal distribution of the forms in the spring samples is typical, while the summer suspended matter differs by the F2 form’s predominance (53–61% for Zn and Pb). The main conclusion from the acquired data is that the geochemical mobility of all the studied elements, except for cadmium, in the summer low water suspended matter is higher than in the spring suspended matter. The more intensive biogeochemical processes in August, the high level of organic matter, and the higher contribution of phytoplankton lead to the intensification of the metals’ geochemical activity in the Northern Dvina suspended matter in the end of the summer compared to the spring high water period when the physical processes are predominant over the biogeochemical ones due to the high speeds of the freshened waters flow.  相似文献   

14.
依据1987年6月、1996年12月、1997年2月和1998年7月在东海北部所取得的悬浮体、温度和盐度资料就该区冬季和夏季的悬浮体分布、影响因素和输运进行了研究,结果表明该区悬浮体分布具有明显的季节性变化,在中、外陆架区悬浮体含量冬季明显高于夏季.悬浮体的分布及输运受到东海环流、风暴和潮流等的影响,其中东海环流的季节性变化是主要影响因素.受台湾暖流的阻隔,冬季和夏季长江入海泥沙在东海基本不能越过124°00'E以东海域.黄海沿岸流携带着老黄河口水下三角洲的再悬浮沉积物向陆架东南扩散,其搬运的量和在中、外陆架区的扩散范围冬季显著大于夏季.在黄海暖流的阻隔下,陆架悬浮体冬季和夏季在32°N断面很少能扩散至126°30'E以东海域.台湾暖流和黑潮爬升水的阻隔作用使得冬季和夏季陆架悬浮体在P-N断面也基本不能扩散至陆架边缘.冬季在东海北部可有部分陆架悬浮体输送到冲绳海槽,但有区域性,其输送的可能位置是在P-N断面以北、32°N断面以南之黄海沿岸流向东南延伸的陆架边缘;夏季陆架悬浮体基本滞留在陆架区.  相似文献   

15.
The concentrations of suspended matter and particulate Cd, Cu, Pb and Zn were determined for 36 samples collected at 6 stations in the Antarctic Ocean during December, 1970 and January, 1971 using membrane filters. The concentration of suspended matter was determined gravimetrically and trace metal levels were determined using anodic stripping voltammetry. For waters deeper than 100 m the concentration of suspended matter was < 100 μg l?1. Concentrations up to 542 μg l?1 were recorded between surface and 100 m. Individual concentrations of the metals were scattered with depth. Average concentrations of particulate metals were: Cd, 3.5 ng l?1; Cu, 100 ng l?1; Pb, 35 ng l?1; and Zn, 230 ng ;l?1 These measurements represent non-steady state conditions of early Antarctic summer as the ice pack disintegrates and biological activity increases.  相似文献   

16.
东海颗粒碳的垂直转移过程   总被引：7，自引：3，他引：7  
在１９９３年和１９９４年两个航次中，利用震动式取样从东海陆架取得３个柱状岩芯样品。对其进行了ＰＯＣ，ＰＩＣ，ＰＯＮ含量和粒度分析，并同其上覆水体的ＰＯＣ，ＰＩＣ以及总颗粒物的垂直通量和悬浮体作了比较。  相似文献   

17.
The objectives of this study were to investigate the seasonality, abundance, sources and bioreactivity of organic matter in the water column of the western Arctic Ocean. The concentrations of particulate and dissolved amino acids and amino sugars, as well as bulk properties of particulate and dissolved organic matter (DOM), were measured in shelf, slope and basin waters collected during the spring and summer of 2002. Particulate organic matter concentrations in shelf waters increased by a factor of 10 between spring and summer. Dissolved organic carbon (DOC) and nitrogen (DON) concentrations exhibited only minor seasonal variations, whereas dissolved amino acid concentrations doubled between spring and summer, and dissolved amino sugars increased by 31% in shelf waters of the Chukchi and Beaufort Seas. Concentrations of DOC did not exhibit a significant seasonal change in surface waters of the Canada Basin, but dissolved amino acid concentrations increased by 45% between spring and summer. No significant seasonal differences were detected in the concentration or composition of DOM in waters below 100 m in depth. Concentrations of particulate and dissolved amino acids and amino sugars were strongly correlated with chlorophyll-a, indicating a plankton source of freshly produced organic matter. The amino acid and amino sugar compositions of freshly produced DOM indicated that a large portion of this material is bioavailable. While freshly produced DOM was found to be relatively bioreactive, preformed DOM in the Arctic appears to be less bioreactive but similar in degradation state to average DOM in the Atlantic and Pacific. These data demonstrate substantial summer production of POM and DOM on the Chukchi and Beaufort shelves that is available for utilization in shelf waters and export to the Canada Basin.  相似文献   

18.
The concentrations of particulate silica and inorganic suspended matter in the surface water of the North Pacific were determined. The concentration of particulate silica depends on latitude, and increases with increasing degree of the north latitude. The concentration of inorganic suspended matter shows a similar distribution pattern, but it is of much smaller magnitude. There exists a high positive correlation between the concentrations of particulate silica and nutrients. On the other hand, a weak negative correlation is found between the concentrations in surface seawater of particulate silica and radioactive 210Pb which originate chiefly from precipitation and dry fallout. This evidence suggests that the particulate silica in the sea is mainly of biogenic origin and the contribution of nonbiogenic silica, i.e., of terrestrial origin, is small.  相似文献   

19.
The distribution of the natural radionuclide 210Po in the water column along a horizontal transect of the continental shelf, slope and deep basin regions of the East Sea (Sea of Japan), a marginal sea of the Northwest Pacific Ocean, was investigated, and its behavior is described here. The settling fluxes of particulate 210Po in the deep basin along with 210Pb, 234Th and biogenic matter were also determined. 210Po inventories in the water column were observed to decrease from winter to summer in all stations, probably due to increased influx of 210Po-poor Kuroshio Water of the Northwest Pacific Ocean during summer. Vertical profiles of dissolved and particulate 210Po along with the settling fluxes of particulate 210Po in the deep basin station have enabled us to evaluate temporal variations and residence times of 210Po. In the slope and basin, activities of dissolved 210Po generally decreased from the surface to the bottom water, with maximum activity just below the subsurface chlorophyll a maximum at 50–75 m depth in spring and summer. These subsurface peaks of dissolved 210Po activity were attributed to the release of 210Po from the decomposition of 210Po-laden biogenic particulate organic matter. In the deep basin, despite the decrease in total mass flux, the sinking flux of particulate 210Po was higher in the deeper trap (2000 m) than in the shallower one (1000 m), probably due to scavenging of dissolved 210Po from the water column during particle descent and/or break-down of 210Po-depleted particulate matter between 1,000 m and 2,000 m depths. In general, the ratios of the particulate phase to the dissolved phase of 210Po (Kd) increased with depth in the slope and basin stations. 210Po removal from the water column appears to depend on the primary productivity in the upper waters. There is an inverse relationship between Kd and suspended particulate matter (SPM) concentration in the water column. From the 210Po activity/chlorophyll a concentration ratios, it appears that sinking particles arriving at 1000 m depth were similar to those in the surface waters.  相似文献   

20.
AVHRR/NOAA-11 satellite images of the C1 (580–680 nm) and C2 (725–1100 nm) channels were used to quantify the suspended particulate matter discharged into the ocean by the Gironde estuary (France). The calibration method is based on a comparison between satellite values (AVHRR reflectances) and suspended particulate matter (SPM) concentrations at the sea surface, measured in situ. To correct the aerosol variations a C1-C2 image subtraction is applied. However, when the SPM concentration is greater than about 15 mg l−1, the C2 channel image is affected by water turbidity and the C1-C2 correction cannot be used. The C1 channel is more sensitive, and we were able to distinguish SPM concentration variations greater than 0.5 mg l−1. A subtraction of two images recorded with a 24 h interval was carried out to evaluate vertical and horizontal fluxes. The residual image shows the quantity of particles leaving the surface layer. To assess horizontal displacements, turbid fronts were mapped by means of an image gradient analysis. Major and minor fronts recorded each day, superimposed to outline displacements (gradients and orientations), were displaced from the Gironde estuary to the West and the Northwest.During the ECOFER cruises (1989–1991), several AVHRR scenes were processed using an atmospheric correction based on the low SPM concentrations (“ocean pixel subtraction”). Generally, surface particulate matter is confined to the inner continental shelf. Higher values were observed during the ECOFER 4 cruise. Suspended particulate matter concentrations with the maximum extension appeared during the ECOFER 1 cruise. Concentrations were very low during the ECOFER 5 cruise, even in the lower estuary. This was due to low summer discharges that occurred during the dry period of 1988–1991 in France. During these surveys, estimated SPM concentrations were less than 1.5 mg l−1 in the ECOFER area.  相似文献   

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