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1.
在IONESS系统中浮游介形类的昼夜垂直移动 总被引：1，自引：0，他引：1
根据IONESS系统对浮游动物的分层采样结果,研究浮游介形动物的昼夜垂直移动.浮游介形类存在着整个类群的昼夜垂直移动,白天其丰度最大值记录于200～300m层,并往上层水域递减,而夜间则明显往上层密集,丰度最大值提升至50～100m层;就物种多样性而言,由于工作水层(0～1000m)以深水层的众多种类于夜间上升至1000m以浅水层,导致工作水层内总种数由白天的49种剧增至夜间的78种,增幅达60%,各分层的种类数都有较明显的增加,750～1000m层的增幅最大,达150%,其次为50～100m层(增幅达125%);各种浮游介形类有不同的昼夜垂直移动模式,但绝大多数种类属于夜间上升型,少数种类属于不敏感类型,极少数种类却具夜间下降的移动特点.浮游介形类虽具明显的昼夜垂直移动,但这一变动往往局限于一定水深范围,从而反映出介形类的层状分布特点,可划分为广深分布型、上层分布型、中层分布型和下层分布型. 相似文献
2.
台湾南湾区秋末冬初海樽类的种类组成和数量分布 总被引：6，自引：0，他引：6
根据2001年11月2--3日和12月8--10日在台湾南湾12个测站分别用2种圆锥形浮游生物网(长180cm，网口直径45cm，网目333μm或200μm)采集表层和底层的浮游动物样品，分析了南湾浮游海樽类的种类组成和数量分布，其鉴定海樽类16利，其中7种为台湾周围海域新记录。东方双尾纽鳃樽和小齿海樽为优势种。南湾海樽类的种类数及个体数量均以12月多于11月。讨论了水文条件与海樽类时空分布的关系，认为外海高盐水团足南湾冬季海樽类生态特征的主要制约因子。典型的高温高盐种大西洋火体虫、长吻纽鳃樽、安纽鳃樽、多手纽鳃樽、书氏纽鳃樽、羽环纽鳃樽和斑点纽鳃樽等可以作为外海高温高盐水入侵南湾的指标种。与邻近海域比较，秋冬季南湾与台湾岛以东海域海樽类的区系特征比与台湾海峡和南海北部更加相似。 相似文献
3.
三亚湾浮游动物的昼夜垂直移动 总被引：4，自引：0，他引：4
1998年11月和1999年1、4、8月在三亚湾(109°28′6″E,18°13′36″N;水深约15m)进行了24h的浮游动物昼夜连续分层采样。结果表明,浮游动物的昼夜垂直移动季节变化显著,春季在中上层(0—10m)分布,夏季营显著的白天下降、夜晚上升的移动。三亚湾浮游动物的昼夜垂直移动可划分为移动显著和不显著两大类型,前者又可划分为白天下降、夜晚上升,白天上升、夜晚下降,傍晚和清晨上升、白天和夜晚下降3种类型;后者又可划分为中上层分布和各水层均匀分布2种类型。此外,有些种类的昼夜垂直移动无明显的规律。光照是影响浮游动物昼夜垂直移动的重要因素。浮游植物密度与浮游动物的昼夜垂直移动关系不密切。夏季浮游动物的大型种类肥胖箭虫(Sagittaenflata)、亚强次真哲水蚤(Subeucalanussubcrassus)可以穿越温跃层的上界而进入表层。浮游动物昼夜垂直移动的幅度不但与种类的个体大小有关,而且也与水深和种类的习性有关。 相似文献
4.
2013-09利用船载Simrad EK60科学鱼探仪(38kHz)对南海深海声学散射层进行了连续监测,并结合变水层拖网采样分析了其垂直分布和昼夜变化。结果表明,南海深海存在2个明显的声学散射层,特征深度分别为0~100m和350~700m,并且2个散射层间存在较为明显的昼夜垂直移动现象。其随时间变化情况为:16∶00-19∶00,350~700m散射层中的部分生物逐渐向上移动到0~100m散射层;04∶00-07∶00,这部分上升的生物又逐渐移回至350~700m散射层。变水层拖网采样结果发现,白天0~100m散射层内渔获物数量较少,夜间0~100m散射层内渔获物较多,验证了声学映像所检测到的2个散射层间确实存在昼夜移动的现象。 相似文献
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南沙群岛海区毛颚动物的昼夜垂直移动 总被引：10，自引：2，他引：10
对1997年11月和1999年4月、7月在南沙群岛海区3个昼夜连续测站采集的毛颚动物样品进行了研究。结果表明，这些水域的毛颚动物的昼夜垂直移动可以划分为3个类型：种类作显著移动，不作显著移动和仅在夜晚移动。作为昼夜垂直移动显著的种类，又可以把它们划分为：（1）种类在整个水柱移动；（2）种类在上层（0－60m）移动；（3）种类在中层（60－100m）移动。作为昼夜垂直移动不明显的种类，又可以把它们分为：（1）种类分布在于上层（0－60m）。（2）种类分布于底层（100－200m）。种类在白天下降或附着在海底物体上，仅在夜晚移动。光照，水温，食物和种类特征是影响本水域毛颚动物昼夜垂直移动的重要因素。 相似文献
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北黄海海樽类的种类组成和分布特征 总被引：1，自引：0，他引：1
《中国海洋大学学报(自然科学版)》2015,(6)
为研究北黄海海樽类的群落特征,根据2006—2007年北黄海(36.95°N~39.66°N,120.95°E~124.02°E)海域4个季节的海洋调查资料,分析了北黄海海樽类的种类组成、数量变化、分布特征及其与环境的关系。结果显示:北黄海共记录到浮游海樽类4种,其中春季1种,夏季3种,秋季1种,冬季在北黄海未记录到海樽类。梭形纽鳃樽(Salpafusiformis)在春季和夏季两个季节都有出现,分布区主要位于黄海中部,且夏季大于春季,两季节的平均丰度分别为5.2和2.5ind/m3。贝环纽鳃樽(Cyclosalpa bakeri)仅在夏季出现,分布在黄海冷水团区,平均丰度仅为0.1ind/m3。软拟海樽(Dolioetta gegenbauri)仅在夏季1个站位出现,丰度仅为0.2ind/m3。暖水种小齿海樽(Doliolum denticulatum)是秋季北黄海唯一记录到的海樽类,分布几乎遍及整个研究水域,并具有很高的丰度,平均丰度为34.4ind/m3。典型的暖水种小齿海樽在北黄海的大量出现并成为浮游动物的优势种可能是温带水域的海洋生态系统对全球变暖的响应信号。 相似文献
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运用荧光显微技术分析北黄海夏季浮游病毒的分布 总被引：3，自引：1，他引：2
运用荧光显微技术(Epifluorescence Microscopy,EFM),对2006年夏季北黄海水域31个站点的病毒丰度进行了检测,对浮游病毒丰度在水平分布,垂直分布和昼夜变化上进行了探讨.北黄海水域浮游病毒直接检测量(Virus Direct Count,VDC)为(1.58×106～1.38×107)/mL,平均为5.86×106/mL.在水平分布上,表层、30 m和底层水在辽东半岛头部附近出现了病毒较高区域,近海水域的病毒丰度较中部水域高(P＜0.05).在垂直分布上,表层浮游病毒丰度高于30 m水层和底层(P＜0.05).在昼夜变化上,表层水体中浮游病毒量有明显的变化,10 m水层和30 m水层的病毒丰度昼夜变化较明显,底层病毒丰度昼夜趋势平缓.利用多元相关分析可知,北黄海夏季浮游病毒丰度与站位总水深(P＜0.01)和盐度(P＜0.05)成一定的负相关性,与温度无明显相关性(P＞0.05). 相似文献
9.
北黄海典型水域春夏季浮游植物的昼夜变化 总被引：1，自引：0，他引：1
根据黄海西北部2006年夏季3个连续站和2007年春季1个连续站垂直分层拖网的调查资料,研究了黄海西北部典型海区浮游植物的昼夜垂直变化.夏季共检出浮游植物79种,主要优势种为旋链角毛藻Chaetoceros curvisetus、梭角藻Ceratium fusus、三角角藻Ceratium tripos和具槽帕拉藻Paralia sulcata;春季检出51种,主要优势种为浮动弯角藻Eucampia zodiacus、具槽帕拉藻和尖刺伪菱形藻Pseudo-nitzschia pungens.夏季L01站受潮汐的影响各水层低潮期浮游植物细胞丰度高于高潮期,垂直分布趋势为表层细胞丰度最高,底层最低.而由于底栖硅藻的细胞再悬浮作用夏季L02、L03站和春季L02站底层细胞丰度高于表层,但各水层细胞丰度的昼夜变化相对较平缓. 相似文献
10.
东海浮游动物昼夜垂直移动的初步研究 总被引：12，自引：0，他引：12
于 1 994年 4月 (春季 )和 1 1月 (秋季 )在东海 41 0站 ( 1 2 4°5 9′E ,2 9°32′N ,水深 85m)对浮游动物的昼夜垂直移动变化规律进行 2 4h定点连续观测。结果表明 ,春季和秋季浮游动物总数量的昼夜垂直移动变化均不明显 ,其数量主要分布在 0— 1 0m的表层水域 ;在桡足类的优势种中 ,个体较大的中华哲水蚤第V期和成体、精致真刺水蚤 ,以及磷虾类的中华假磷虾和太平洋磷虾等 ,其昼夜垂直移动比较明显。而一些个体较小的种类 ,如小拟哲水蚤、近缘大眼剑水蚤和其他种类的幼体、被囊类的优势种长尾住囊虫等 ,无论是在春季还是在秋季 ,它们的昼夜垂直移动均不明显 ,主要集中在 0— 1 0m的表层水域 相似文献
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A 30-month time series of mean volume backscattering strength (MVBS) data obtained from moored acoustic Doppler current profilers (ADCPs) is used to analyze the evolution of vertically migrating scattering layers and their seasonal and annual variability in the Arabian and Oman Seas. Substantial diel vertical migration (DVM) is observed almost every day at all three mooring sites. Two daytime layers (Layers D1 and D2) and one nighttime layer (Layer E1) are typically present. The greatest biomass is observed near the surface during the night in Layer E1 and at depth between 250 and 450 m during the daytime in Layer D2. All layers are deepest during the spring inter-monsoon and shallowest during the summer/fall southwest monsoon (SWM). Seasonal modulation of the D2 biomass change is evident in our high-resolution data. The lowest biomass in D2 is measured in the early summer (May or June) followed by a rapid biomass increase during the SWM (June–November) until the biomass reaches a maximum at the end of the SWM season. Short-period oscillations in D2 biomass are often seen with periods ranging from days to one month. Occasionally, a lower nighttime layer E2 is formed between 180 and 270 m, mostly near the time of full moons. The upper daytime layer D1 is centered at 200 m and densely concentrated. It is only formed during the winter northeast monsoon (NEM) and the spring inter-monsoon. The influence of physical processes on layer distribution is also investigated. Interestingly, the two daytime layers are found to be formed at the two boundaries of the Persian Gulf outflow water (PGW) and follow the seasonal depth change of the PGW. The timing of the DVM and the formation, persistence, decay and reformation of the deep scattering layers seem to be governed by light, both solar and lunar. The scattering strength, the layer depth and the layer thickness are likewise closely related to the Moon phase at night. Cloud coverage, the isotherm and the isohaline also appear to affect the distribution and depth of the scattering layers. The continuous multiple-year acoustic data from ADCPs allow us, for the first time, to study the seasonal and annual variations of scattering layers in this region. 相似文献
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Using the hydroacoustic method with a 200 kHz scientific echo sounding system,the diel vertical migration(DVM) of the sound-scattering layer(SSL) in the Yellow Sea Bottom Cold Water(YSBCW) of the southeastern Yellow Sea was studied in April(spring) and August(summer) of 2010 and 2011.For each survey,13–27 hours of acoustic data were continuously collected at a stationary station.The acoustic volume scattering strength(Sv) data were analyzed with temperature profile data.In the spring of both 2010 and 2011,the SSL clearly showed the vertical migration throughout the entire water column,moving from the surface layer at night to near the bottom during the day.Conductivity,temperature,and depth data indicated that the entire water column was well mixed with low temperature of about 8 C.However,the SSL showed different patterns in the summers of 2010 and 2011.In the summer of 2010(28 C at the surface),the SSL migrated to near the bottom during the day,but there were two SSLs above and below the thermocline at depth of 10–30 m at night.In the summer of 2011(20 C at the surface),the SSL extended throughout the entire water column at night,possibly owing to an abrupt change in sea weather conditions caused by the passage of a Typhoon Muifa over the study area.It was concluded that the DVM patterns in summer in the YSBCW area may be greatly influenced by a strengthened or weakened thermocline. 相似文献
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Diel Vertical Migration of the Marine Cladoceran Podon Leuckarti: Variations with Reproductive Stage
Diel vertical migration (DVM) of the marine cladoceran Podon leuckarti was investigated with reference to their reproductive stages and size. Males and females, except for gamogenic females with an advanced resting egg (GA), aggregated at the near-bottom layer or at the surface during the day and dispersed into the water column at night. Both the near-bottom aggregation and the surface aggregation during daytime are suggested to be behavior that reduces the predation risk from visual predators. However, GA aggregated in the near-bottom layer during daytime and avoided the surface layer. The near-bottom aggregation might be more effective behavior for GAs to reduce risk of visual predation than the surface aggregation because of the conspicuous resting egg they carried. These results show that carrying an advanced resting egg influenced the DVM of P. leuckarti. 相似文献
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Acoustic volume backscattering strength data were collected and Conductivity Temperature Depth (CTD) measur e m e n t s were
conducted in the southern Yellow Sea in summer 2005 and 2006. The high temporal and vertical resolution acoustic data measured
with a 307 kHz Acoustic Doppler Current Profiler (ADCP) and a 250 kHz acoustic Doppler profile (ADP) had dominant diel variation,
which resulted from vertical migration of sound scatterers. Some scatterers congregating in the bottom layer in the daytime
migrated upward at dusk, and migrated downward into the bottom layer at dawn. The migration speeds were estimated. More than
33 days data show that the diel migration varies with time. The feature of migration measured with ADCP and ADP is consistent
to some extent with what is described in the study on vertical migration of zooplankton in the southern Yellow Sea with conventional
net samples. 相似文献
15.
To understand the effects of the Yellow Sea Cold Bottom Water(YSCBW)on the diel vertical migration(DVM)of the copepod Calanus sinicus,we surveyed vertical distribution of C.sinicus at a fixed station in the Yellow Sea before(spring)and during(summer)formation of the YSCBW.Cold water(<10 C)was observed in the bottom layer when the water column was thermally stratified in summer,but the water column was thermally well-mixed in spring 2010.Samples were collected from five different layers at 3-h intervals using an opening-closing net.Adult females(1–155 ind./m3)showed a clear normal DVM pattern throughout the entire water column in spring,whereas adult males did not migrate.DVM of copepodite V(CV)individuals was not clear,but the maximum abundance of CI–CIV occurred consistently in the upper 10–20 m layer,where there was a high concentration of chlorophyll-a(Chl-a)(0.49–1.19μg/L).In summer,weak DVM was limited to cold waters beneath the thermocline for adult females(<30 ind./m3),but not for adult males.The maximum abundance of CI–CIV also occurred consistently in the subsurface layer(20–40 m)together with high concentrations of Chl-a(0.81–2.36μg/L).CV individuals(1–272 ind./m3)moved slightly upward nocturnally to the near-surface layer(10–20 m),where the average temperature was 25.74 C,but they were not found in the surface layer(0–10 m;28.31 C).These results indicate that the existence of the YSBCW affected food availability at depth and the vertical temperature distribution,leading to variation in the amplitude and shape of stage-specific vertical distributions(CI to adults)in C.sinicus before and during the formation of cold waters in the Yellow Sea during the study period. 相似文献
16.
Acoustic Doppler current profiler （ADCP） receives echoes from sound scatterers, then their speed is calcu- lated by the Doppler effect. In the open ocean, most of these backscatterers are from the plankton. The sound scatterers descend down to depth at around dawn, their mean speed is 2.9 cm/s, then they ascend up to the surface layer at around dusk with a mean speed of 2.1 cm/s, in the Luzon Strait. The descending speed is faster, which suggests that this zooplankton population may accelerate its downward migration under the action of the gravity. The vertical distribution of a mean volume backscattering strength （MVB- S） in the nighttime has two peaks, which locate near the upper and lower boundary layers of halocline, respectively. However, the backscatterers only aggregate near the surface layer in the daytime. The diel ver- tical migration （DVM） of sound scatterers has several characteristic patterns, it is stronger in summer, but weaker in winter, and the maximum peak occurs in September. The DVM occurrence is synchronous with the seawater temperature increasing at around dawn and dusk, it may affect the ocean mixing and water stratification, 相似文献
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利用深海潜标所搭载的声学多普勒流速剖面仪(acoustic doppler current profiler,ADCP)得到的后向散射强度Sv,研究了黑潮-亲潮混合区浮游动物的垂向分布、其昼夜垂直迁移(diel vertical migration;DVM)的基本特征、多时间尺度变化及对反气旋式中尺度暖涡的响应.结果表... 相似文献
19.
北太平洋亚热带环流区与西太平洋暖池区浮游动物群落垂直分布的差异及其对碳通量的意义 总被引：1，自引：0，他引：1
The mesozooplankton in both epipelagic and mesopelagic zones is essentially important for the study of ecosystem and biological carbon pump. Previous studies showed that the diel vertical migration(DVM) pattern of mesozooplankton varied among ecosystems. However, that pattern was largely unknown in the Western Pacific Warm Pool(WPWP). The vertical distribution, DVM and community structure of mesozooplankton from the surface to 1 000 m were compared at Stas JL7K(WPWP) and MA(North Pacific Subtropical Gyre, NPSG). Two sites showed similarly low biomass in both epipelagic and mesopelagic zones, which were in accordance with oligotrophic conditions of these two ecosystems. Stronger DVM(night/day ratio) was found at JL7K(1.31) than that at MA(1.09) on surface 0–100 m, and an obvious night increase of mesopelagic biomass was observed at JL7K, which was probably due to migrators from bathypelagic zone. Active carbon flux by DVM of zooplankton was estimated to be 0.23 mmol/(m2·d) at JL7K and 0.16 mmol/(m~2·d) at MA. The community structure analysis showed that calanoid copepods, cnidarians and appendicularians were the main contributors to DVM of mesozooplankton at both sites. We also compared the present result with previous studies of the two ecosystems,and suggested that the DVM of mesozooplankton was more homogeneous within the WPWP and more variable within the NPSG, though both ecosystems showed typically extremely oligotrophic conditions. The different diel vertical migration strength of mesozooplankton between NPSG and WPWP implied different efficiency of carbon pump in these two ecosystems. 相似文献