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1.
透明胞外聚合颗粒物(TEP)具有高黏性、低密度和高碳氮比等特性,在颗粒有机物的聚集以及食物网循环中发挥着重要作用。为了解近岸海域TEP的分布动力学规律与机制,本文对温州近海夏秋季节水体中透明胞外聚合颗粒物的分布进行调查,并结合多项环境要素的主成分分析与相关性分析,探究了浙江南部近岸海域TEP分布的影响因素。结果显示,温州近海TEP秋季平均含量明显高于夏季,夏季TEP分布变化主要受陆地径流(瓯江)作用影响,而秋季主要受闽浙沿岸流影响。受沿岸流影响,秋季TEP的主要来源可能是其他海域以及底层颗粒物再悬浮。此外,由浮游植物释放的TEP对夏季的POC贡献最大,而秋季外源性TEP对POC的贡献较夏季有所升高。  相似文献   

2.
磷元素是海洋基础营养盐之一,其赋存形态及分布直接影响海区的初级生产力,是海洋生物地球化学循环的重要驱动力。但大河河口与近海等重要的水生关键带水动力循环过程复杂,导致悬浮颗粒物(SPM )中磷元素的赋存形态和分布特征变化多端,亟须深入研究。根据2016年春季(4?5月)、夏季(7月)和秋季(9?10月)对浙江近岸海域的调查结果,本研究分析了浙江近岸海域SPM中总磷(TPP)、无机磷(PIP)和有机磷(POP)的含量水平、空间分布特征和影响因素。结果表明,浙江近岸海域SPM中TPP含量范围为0.13~66.13 μmol/L,均值为3.35 μmol/L;PIP含量范围为0.03~34.19 μmol/L,均值为1.97 μmol/L;POP含量范围为0.06~31.94 μmol/L,均值为1.39 μmol/L。PIP是浙江近岸海域水体中TPP的主要存在形式,占52.3%。春季浙江近岸海域表层TPP含量占总磷(TP)含量的19.3%~97.7%。春、秋季的SPM中,TPP、PIP和POP含量空间分布相似,均呈现由内湾向外海逐渐降低的变化趋势。PIP、POP与SPM呈显著的正相关性,表现出高SPM含量的海区有着较高的颗粒态磷含量,说明其受陆源输入的影响。春季盐度大于28且SPM含量小于20 mg/L的外侧远海海域,POP与Chl a的相关系数和斜率均明显高于PIP与Chl a的相关系数和斜率,说明该区域浮游植物是POP的主要贡献来源。  相似文献   

3.
舒逸  张桂成  孙军 《海洋学报》2018,40(8):110-119
透明胞外聚合颗粒物(TEP)是凝聚网的重要组成部分甚至核心,在微尺度范围上形成了水环境结构的重要梯度,对于元素地球化学生物循环、碳沉降以及食物网有着举足轻重的作用。本文研究了东海典型断面PN透明胞外聚合颗粒物的分布特征及来源。结果表明:东海典型断面PN透明胞外聚合颗粒物含量介于28~376 μg Xeq./L之间,平均值为(115±67)μg Xeq./L;呈现出明显的夏季 > 冬季 > 秋季 > 春季的季节变化特征以及近岸 > 外海和底层 > 表层的分布趋势。通过对比透明胞外聚合颗粒物分布趋势和硅藻、甲藻分布趋势以及统计分析得出,东海典型断面PN透明胞外聚合颗粒物主要来源于硅藻,甲藻贡献不大;而外海TEP的来源可能主要由超微型浮游植物贡献。  相似文献   

4.
2013年夏季黄、渤海颗粒有机碳分布及来源分析   总被引:3,自引:3,他引:0  
本文根据2013年夏季黄、渤海海域航次获得的颗粒有机碳(particulate organic carbon, POC)、叶绿素a(chlorophyll a, Chl a)和总悬浮颗粒物(total suspended particles, TSP)数据,结合同步获得的水文环境参数,综合探讨该区夏季POC时空分布特征,以及在不同温盐深水团中POC的主要影响因素。结果表明:在整个研究区POC的浓度范围为102.3~1850.0 μg/L,平均值为(383.7±269.6) μg/L,分布呈现出近岸高、远海低、表层低、底层高的特征。苏北外浅滩海域和北黄海东北区域的10 m层和底层为POC高值区,苏北外海域受到陆源输入、沿岸流混合作用和浮游植物光合作用的影响,POC上下混合均匀且浓度高;南黄海中部因受黄海环流的影响,水体中浮游植物生产力水平低,POC浓度较低。在垂直分布上,近岸海域受陆源输入和再悬浮影响POC浓度高,上下混合均匀;在南黄海和北黄海中部受到黄海环流和黄海冷水团的控制,浮游植物生产力水平低,POC浓度低。对不同温盐水团中POC的影响因素分析发现,在高温低盐水团中,POC受浮游植物初级生产和陆源输入的共同影响;在温盐适中区真光层海水中,浮游植物的初级生产是POC的主要来源;底层的冷水团区,POC主要来源为上层海水中颗粒物的沉降和底层再悬浮作用。  相似文献   

5.
夏季珠江口透明胞外聚合颗粒物分布特征   总被引:3,自引:0,他引:3       下载免费PDF全文
本文研究夏季珠江口透明胞外聚合颗粒物(TEP)含量以及分布特征.结果表明,珠江口TEP含量(以黄原胶物质的量计算,下同)范围在85.0-1234.9μg·L-1之间,平均值为690.9μg·L-1.表层和底层TEP均值分别为562.3μg·L-1和778.2μg·L-1,大部分站位表层TEP含量略低于底层.TEP在表层分布自上游至下游逐渐递增,而向外海以及人海口东西两侧延伸逐渐降低.内河口为底层TEP含量高值区,虎门附近S3站TEP含量最高.TEP与不同粒径浮游植物叶绿素a的相关性分析表明微型浮游植物(粒径3-20μm)可能对珠江口TEP贡献较大.珠江口TEP/Ch1a比值与活性硅酸盐、硝酸盐、铵盐和总磷浓度呈现负相关性;表层TEP/Ch1a比值与盐度呈现正相关性,这表明盐度和营养盐可能是影响TEP含量的重要因素.  相似文献   

6.
方涛  刘凯  冯志华  李游 《海洋科学》2019,43(12):67-73
2017年4月作者对海州湾临洪河口海域16个站位的常规理化因子以及浮游植物粒级结构进行了采样和分析,结果表明:调查海域盐度和温度均值分别为35.2和11.2℃,均由近岸到外海逐渐增大;悬浮物质量浓度在3.4 mg/L~137.6 mg/L变化,均值为22.8 mg/L,由近岸到外海逐渐减少,水体逐渐清澈; pH均值为8.29,近岸低,外海高; DO均值为9.8 mg/L, COD在0.34 mg/L~6.55 mg/L变化,均值为3.42mg/L,DO和COD分布规律不明显;浮游植物粒级组成以微型与小型浮游植物为主,其叶绿素a质量浓度平均值与范围分别为1.48μg/L(0.68μg/L~3.13μg/L)、9.14μg/L(2.69μg/L~25.50μg/L),且呈现自沿岸河口向外海逐渐递减的趋势;而微微型浮游植物叶绿素a质量浓度平均值仅为0.27μg/L,且分布较不规律;小型浮游植物对浮游植物总生物量的贡献率最大,高达83.89%,微型及微微型浮游植物的贡献率分别为13.60%和2.52%;在相关性分析中,各项环境因子对小型浮游植物的分布有较大的影响,其中悬浮物、pH与小型浮游植物叶绿素a浓度表现出显著相关(P0.05),溶解氧、盐度与小型浮游植物叶绿素a质量浓度呈极显著相关(P0.01),微型、微微型浮游植物的分布与各项环境因子的相关性不明显。  相似文献   

7.
为更清楚了解浙东海域浮游植物的初级生产力情况,于2006年8月(夏季)和2007年1月(冬季)在浙东海域28°00′~30°00′N、122°00′~127°30′E设置了3条调查断面,共布设25个观测站位,现场采用荧光连续法对叶绿素a进行测定,初步研究了该海域叶绿素a的空间分布特征,并探讨了水体温度、营养盐和浊度对叶绿素a分布的影响。结果表明:夏季,叶绿素a分布趋势为近岸(平均质量浓度为2.01μg/L)>外海(平均质量浓度为0.52μg/L),其主要垂直分布类型为递增型、递减型和单峰型;冬季,叶绿素a分布趋势为外海(平均质量浓度为0.50μg/L)>近岸(平均质量浓度为0.33μg/L),主要垂直分布类型为递增型、均匀型、单峰型和双峰型。夏季调查海域浮游植物叶绿素a平均质量浓度为0.93μg/L,明显高于冬季(0.46μg/L)。温度、营养盐和浊度是影响研究区夏、冬季叶绿素a分布的主要环境因子。  相似文献   

8.
大亚湾海域尿素与浮游生物脲酶活性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
于2010~2011年间分4个季节,对大亚湾海域尿素浓度及浮游生物的脲酶活性开展调查研究,结合相关理化环境及生物因子,分析大亚湾海域尿素的可利用性及其对浮游植物群落演替的影响。结果表明,海区尿素浓度变化范围为0.81~8.54μmol N·L-1,夏季尿素含量最高,达4.32±1.65μmol N·L-1;冬季含量最低,为1.57±0.49μmol N·L-1。夏、秋季节有很多站位尿素水平甚至超过溶解无机氮(dissolved inorganic nitrogen,DIN)含量1~3倍,表明尿素是大亚湾海域浮游植物生长不可忽略的重要氮源。较高水平的尿素主要分布在养殖区和靠近陆地的近岸海域。浮游生物脲酶活性在秋季最高,平均达61.0±33.6nmol N·L-1·h-1,冬、春季脲酶活性常低于检出限。在秋季,浮游生物脲酶活性与甲藻密度密切相关。脲酶已被证明是大洋中浮游植物水解尿素的最主要途径,因此尿素可能在一定程度上影响大亚湾甲藻等浮游植物的生长。  相似文献   

9.
北白令海透明胞外聚合颗粒物的含量与来源   总被引:2,自引:1,他引:1  
透明胞外聚合颗粒物(TEP)是海水中大量存在的黏性颗粒物质,它对于海洋颗粒物的聚集、有机碳的埋藏、食物网物质的传递、痕量金属的清除与迁出等均起着重要作用。本研究开展了夏季北白令海陆架、陆坡和海盆区透明胞外聚合颗粒物含量和分布的研究。结果表明,北白令海TEP含量介于34~628 mg/m3(Xeq)之间,其中陆架、陆坡和海盆区TEP的平均含量分别为240, 145和83 mg/m3(Xeq),整体呈现由陆架向外海降低的趋势。在陆坡和海盆区,TEP含量随着深度的增加而降低,但在陆架近底层水中,观察到TEP高含量的特征,与近底层水高的TSM, POC相对应。TEP与荧光强度、TSM、POC等的关系分析显示,研究海域TEP存在两个来源,其一为海洋上层水体的浮游生物,其主要贡献于陆架上层、陆坡和海盆水体;其二为陆架沉积物的底栖生物,其通过沉积物再悬浮贡献于陆架近底层水。  相似文献   

10.
碱性磷酸酶活性(alkaline phosphatase activity, APA)是海洋研究中用于反映浮游植物磷限制状态的重要指标。在长江口等“氮过剩”海域,磷是控制海域初级生产力水平的主要因子,然而,磷限制的范围常常难以界定,当前对不同粒级浮游植物的磷限制效应所知甚少。该文根据2020年夏季长江口航次资料,给出了海洋表层各粒级浮游植物(Net:≥20 μm;Nano:2~20 μm;Pico:0.8~2 μm)APA、浮游细菌APA(0.2~0.8 μm)和溶解态APA(<0.2 μm)的空间分布特征,并分析了APA与环境要素间的相关性。结果显示,各粒级浮游植物APA均与无机磷酸盐浓度(dissolved inorganic phosphate, DIP)呈显著负相关,这表明DIP浓度是影响浮游植物APA分布的主要因素。在平面分布上,各粒级浮游植物APA在近口门的光限制区均较低,且呈现自口门向外逐渐升高的趋势,与DIP的分布特征相反。Net和Nano级APA[平均值分别为 (40.28±32.35) nmol/(L·h)和(52.38±34.78) nmol/(L·h)]显著高于Pico级APA[平均值为(28.43±20.23) nmol/(L·h)],这表明大粒级浮游植物可能更易受DIP下降的影响。该研究中,诱导浮游植物APA快速升高的DIP浓度为0.159 μmol/L,与近岸区磷限制经验阈值相接近。该研究揭示了夏季不同粒级浮游植物对长江口磷分布的响应特征,有助于理解长江口初级生产过程的环境调控机制。  相似文献   

11.
根据闽东海洋环境监测中心2004年-2006年阂东沿岸生态调查的资料,分析和研究了闽东沿岸浮游植物的生态特征.共鉴定出浮游植物的种类3个门39属共134种,其中硅藻门的种类占总种数的80%,为该调查海域主要门类.主要优势种是中肋骨条藻(Skeletonema costatum)、旋链角毛藻(Chaetoceros curvisetus)、尖刺拟菱形藻(Pseudo—nitzschia pungens)和丹麦细柱藻(Leptocylindrus danicus)等.浮游植物的丰度分布,呈现由调查海域东北侧向西南侧、由近岸向远岸减少的空间特征,夏季高、春季低的季节变化特点,并且有逐年减少的年际变化趋势.本调查海域浮游植物多样性指数较高,群落较稳定.  相似文献   

12.
通过对2010/2011年夏季南极长城湾叶绿素a浓度和海流等环境参数的传感器连续观测;研究其时空变化特征及海流对浮游植物生物量的影响。结果表明;12.9 m水层叶绿素a浓度从12月中旬开始增长;直至2月上旬开始维持相对稳定;期间出现两个高值点(2.74 μg/L和3.76 μg/L)。叶绿素a浓度表现出了24 h周期变化特征;每日叶绿素a浓度最高值出现在正午前后时段的概率要高于其他时段。表层海水受西北风影响;流速较大;约为60~100 cm/s;中层和底层水体流速较小;约为10 cm/s。表层的风海流使海水在长城湾发生辐散;下层海水向上涌升;驱动了水体的垂直交换。长城湾与麦克斯韦尔湾存在水体交换;水体主要从中层进入湾内;从表层输出。长城湾的叶绿素a浓度与流速呈显著负相关;表明低流速环境有利于长城湾浮游植物的生长。  相似文献   

13.
Complex physical, chemical and biological interactions off the Korean coast created several striking patterns in the phytoplankton blooms, which became conspicuous during the measurements of ocean color from space. This study concentrated on analyzing the spatial and temporal aspects of phytoplankton chlorophyll variability in these areas using an integrated dataset from a Sea-viewing Wide Field-of-view Sensor (SeaWiFS), Advanced Very High Resolution (AVHRR) sensor, and Conductivity Temperature Depth (CTD) sensor. The results showed that chlorophyll concentrations were elevated in coastal and open ocean regions, with strong summer and fall blooms, which appeared to spread out in most of the enclosed bays and neighboring waters due to certain oceanographic processes. The chlorophyll concentration was observed to range between 3 and 54 mg m-3 inside Jin-hae Bay and adjacent coastal bays and 0.5 and 8 mg m-3 in the southeast sea offshore waters, this gradual decrease towards oceanic waters suggested physical transports of phytoplankton blooms from the shallow shelves to slope waters through the influence of the Tsushima Warm Current (TWC) along the Tsushima Strait. Horizontal distribution of potential temperature (θ) and salinity (S) of water off the southeastern coast exhibited cold and low saline surface water (θ<19°C; S<32.4) and warm and high saline subsurface water (θ>12°C; S>34.4) at 75dBar, corroborating TWC intrusion along the Tsushima Strait. An eastward branch of this current was called the East Korean Warm Current (EKWC), tracked with the help of CTD data and satellite-derived sea surface temperature, which often influenced the dynamics of mesoscale anticyclonic eddy fields off the Korean east coast during the summer season. The process of such mesoscale anticyclonic eddy features might have produced interior upwelling that could have shoaled and steepened the nutricline, enhancing phytoplankton population by advection or diffusion of nutrients in the vicinity of Ulleungdo in the East Sea.  相似文献   

14.
春、秋季南黄海浮游纤毛虫丰度及生物量的分布差异   总被引:1,自引:0,他引:1  
Seasonal variation of marine plankton spatial distribution is important in understanding the biological processes in the ocean.In this study,we studied spatial distribution of planktonic ciliate abundance and biomass in the central deep area(station depth greater than 60 m) and the coastal shallow area(station depth less than 60 m) of the southern Yellow Sea(32°–36.5°N,121°–125°E) in spring(April) and autumn(October–November) of 2006.Our results showed that both ciliate abundance and biomass in the surface waters were higher in spring((1 490±2 336)ind./L;(4.11±7.81) μg/L) than in autumn((972±823) ind./L;(1.11±1.18) μg/L,calculated by carbon).Ciliate abundance and biomass in the surface waters of the coastal shallow area were similar in spring and autumn.However,in the central deep area,those values were much higher in spring((1 878±2 893) ind./L;(5.99±10.10)μg/L) than in autumn((738±373) ind./L;(0.74±0.76) μg/L).High values of ciliate abundance and biomass occurred in the central deep area in spring and in the coastal shallow area in autumn.Mixotrophic ciliate Laboea strobila was abundant in the central deep area in spring,when a phytoplankton bloom occurred.However,in autumn,L.strobila was abundant in the coastal shallow area.Boreal tintinnid Ptychocyli obtusa was found in spring.Both L.strobila and P.obtusa were concentrated in the surface waters when their abundance was more than 1 000 ind./L.Peaks of these species were in the subsurface waters when their abundance was less than 400 ind./L.This study showed that both high abundance and biomass of ciliates occurred in different areas in southern Yellow Sea seasonally.  相似文献   

15.
We examined bacterioplankton biomass and heterotrophic production (BHP) during summer stratification in the northwestern Mediterranean in four successive stratification seasons (June–July of 1993–1996). Values of phytoplankton biomass and primary production were determined simultaneously so that the data sets for autotrophic and heterotrophic microbial plankton could be compared. Three standard stations were set along a transect from Barcelona to the channel between Mallorca and Menorca, representing coastally influenced shelf waters, frontal waters over the slope front, and open sea waters. Conversion factors from 3H-leucine incorporation to BHP were empirically determined and varied between 0.29 and 3.25 kg C mol-1. Bacterial biomass values were among the lowest found in any marine environment. BHP values (between 0.02 and 2.5 μg C L-1 d-1) were larger than those of low nutrient low chlorophyll areas such as the Sargasso Sea and lower than those from high nutrient low chlorophyll areas such as the equatorial Pacific. Growth rates of bacterioplankton were highest at the slope front (0.20 d-1) and lowest at the open sea station (0.04 d-1). Phytoplankton growth rates were similar at the three stations (∼0.50 d-1). Integrated values of bacterioplankton biomass, BHP and bacterial growth rates did not show significant differences among years, but differences between the three stations were clearly significant. Phytoplankton biomass, primary production, and phytoplankton growth rates did not show significant differences either with year or with station. As a consequence the bacterioplankton to phytoplankton biomass (BB/BPHY) and production (BHP/PP) ratios varied from the coastal to the open sea stations. The BB/BPHY ratio was 0.98 at the coast and ∼0.70 at the other two stations. These ratios are similar to those found in other oligotrophic marine environments. The BHP/PP ratio was 0.83 at the coast, 0.36 at the slope and 0.09 at the open sea station. The last value is also similar to values found in other oligotrophic marine environments. Vertical distribution of these ratios was also examined.The comparison of microbial parameters at the three stations indicates a different kind of relationship between bacterioplankton and phytoplankton in oligotrophic open sea waters and in coastal, nutrient-richer waters. According to such parameters and to the values of the BB/BPHY and BHP/PP ratios, open waters in the northwestern Mediterranean (despite their relatively short distance from the shore) were intermediate between the extremely oligotrophic waters of the eastern Mediterranean or the Sargasso Sea and the more productive waters of the equatorial Pacific.  相似文献   

16.
Coastal marine environments are important links between the continents and the open ocean. The coast off Mangalore forms part of the upwelling zone along the southeastern Arabian Sea. The temperature, salinity, density, dissolved oxygen and stable oxygen isotope ratio (δ18O) of surface waters as well as those of bottom waters off coastal Mangalore were studied every month from October 2010 to May 2011. The coastal waters were stratified in October and November due to precipitation and runoff. The region was characterised by upwelled bottom waters in October, whereas the region exhibited a temperature inversion in November. The surface and bottom waters presented almost uniform properties from December until April. The coastal waters were observed to be most dense in January and May. Comparatively cold and poorly oxygenated bottom waters during the May sampling indicated the onset of upwelling along the region. δ18O of the coastal waters successfully documented the observed variations in the hydrographical characteristics of the Mangalore coast during the monthly sampling period. We also noted that the monthly variability in the properties of the coastal waters of Mangalore was related to the hydrographical characteristics of the adjacent open ocean inferred from satellite-derived surface winds, sea surface height anomaly data and sea surface temperatures.  相似文献   

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