冬季黄、东海一断面表层砂壳纤毛虫群落

于2012年11月18日至12月21日,在黄、东海沿从南向北(26~36°N)一个断面24个站采样调查了表层(4 m)砂壳纤毛虫群落。共发现砂壳纤毛虫17属,32种。各站砂壳纤毛虫种丰富度为2~15种,砂壳纤毛虫总丰度为2 478~88 550个/m3。整个断面优势种为筒状拟铃虫、白领细壳虫、小领细壳虫和钝囊坎虫。巴西拟铃虫仅出现在青岛近岸(24号站),但丰度很高(10 960个/m3)。砂壳纤毛虫种类多样性从南向北降低,从近岸向远岸增加,黏着壳的比例在近岸水浅处较多,在水深大于50 m的站位,透明壳所占比例大大增加。不同种类的砂壳纤毛虫有着不同的分布区域,根据分布区域的不同,可分为南方种,北方种和广布种等。聚类分析结果显示,调查区的砂壳纤毛虫可以分为3个群落。     

春季和夏季渤海湾近岸海域大型砂壳纤毛虫的群落结构

为了解渤海湾砂壳纤毛虫丰度、生物量及种类组成,于2011年春季和夏季在渤海湾天津近岸海域进行砂壳纤毛虫群落的采样调查。两个季节砂壳纤毛虫丰度、生物量、优势种及群落结构均有显著的不同。春季砂壳纤毛虫丰度的范围为0~1608个/L,生物量为0.00~20.03μg/L;夏季砂壳纤毛虫丰度的范围为2~313个/L,生物量为0.03~4.04μg/L。共鉴定出砂壳纤毛虫5属15种,其中拟铃虫属(Tintinnopsis)种类最多。春季的主要优势种为运动类铃虫(Codonellopsis mobilis,优势度为0.79),夏季的主要优势种为斯氏拟铃虫(Tintinnopsis schotti,优势度为0.28)和诺氏薄铃虫(Leprotintinnus nordqvisti,优势度为0.28)。春季砂壳纤毛虫群落的物种丰富度、Shannon指数和Pielou指数均明显低于夏季。     

天津大神堂海域人工鱼礁区砂壳纤毛虫群落的季节变化

于2015年夏季、秋季和2016年春季在天津大神堂海域人工鱼礁区进行砂壳纤毛虫群落的调查。3个季节共鉴定出砂壳纤毛虫10属31种,拟铃虫属（Tintinnopsis）种类最多,夏季砂壳纤毛虫种类最多。砂壳纤毛虫丰度、生物量和群落多样性指数存在明显的季节差异。砂壳纤毛虫丰度夏季最高[（379±355）个/L],秋季最低[（173±190）个/L];生物量夏季最高[（2.74±2.82）μg C/L],秋季最低[（0.23±0.21）μg C/L]。砂壳纤毛虫壳的平均口径夏季最大[（49.64±6.90）μm],秋季最小（26.76±4.55 μm）。砂壳纤毛虫群落Shannon多样性指数夏季最高（2.025±0.574）,春季最低（0.922±0.437）;Pielou均匀度指数秋季最高（0.682±0.276）,春季最低（0.448±0.266）。春季鱼礁区和对照区砂壳纤毛虫优势种存在差异,夏季和秋季鱼礁区和对照区砂壳纤毛虫优势种相同;3个季节鱼礁区第Ⅰ优势种的优势度均明显高于对照区。3个季节鱼礁区砂壳纤毛虫丰度和生物量均高于对照区,这可能是由于投礁后砂壳纤毛虫的适口饵料——nano-浮游植物丰度增加导致;3个季节鱼礁区Shannon多样性指数和Pielou均匀度指数均低于对照区,可能是因为本次调查是在投礁1~2 a后开展的,时间较短,鱼礁区砂壳纤毛虫群落尚不稳定,鱼礁区独特生态系统的变化尚需更长的时间来进行跟踪监测。     

热带西太平洋砂壳纤毛虫的多样性

为了探明热带西太平洋海区砂壳纤毛虫的多样性、垂直分布及纬向变化,我们于2012年11-12月在该海区四个断面采集了0-200 m的水样。共检出砂壳纤毛虫39属124种,多数种类喜好生活在表层和次表层。砂壳纤毛虫种丰富度、丰度以及多样性指数的高值主要出现在比叶绿素浓度最大值稍浅的位置,与温度和叶绿素浓度显著正相关,与盐度和采样深度显著负相关。多数优势种与环境因子间的相关性不显著。热带西太平洋海区砂壳纤毛虫多样性极高,各站种丰富度在25-52之间。在从表层至75 m处的多数采样点香农指数均大于3。该海区砂壳纤毛虫冗余种的比例很高,占砂壳纤毛虫总种类数的87.90%,贡献了砂壳纤毛虫60.38%的丰度,表明热带西太平洋海区砂壳纤毛虫群落对饵料组成和摄食压力改变的应对能力很强,稳定性很高。     

方斑东风螺养殖方式的初步研究

2003年5～11月,水温24．5～32℃,pH8．1～8．3,盐度21．2～32．0时,在湛江市东海岛分别利用室内水泥池、对虾高位池、自然海区砂滩以及水泥沉箱进行了方斑东风螺(Babylonia areolate Larnarck)人工养殖方式的研究。试验结果表明,方斑东风螺养殖的合适密度为：室内水泥池300～400个／m^2高位池和天然海区砂滩100～200个／m^2,水泥沉箱0．63m^3 200～250个／箱;方斑东风螺最佳饵料为蟹类,其次为虾类,然后是鱼类。经过3个月的人工养殖,生长最快的方斑东风螺由平均壳高0．7cm长至4．8cm。     

黑潮及相邻海域表层砂壳纤毛虫分布模式:以夏季黄海、东海至西太平洋断面为例

2019年夏季对沿黄、东海至西太平洋跨越黑潮一个断面(122°E～145°E)的表层砂壳纤毛虫群落进行调查,研究了黑潮中砂壳纤毛虫与相邻水体的差异.根据水文环境及各站位所处的空间位置,我们将研究区域划分为大洋边缘区域、黑潮区域和大洋区域.各站位砂壳纤毛虫的丰度范围为3.95～31.94 ind·L–1,种丰富度范围为6...     

南海北部大型砂壳纤毛虫的水平分布

2007年10月在南海北部设置13个断面(82个站位), 调查大型网采(孔径76 mm)砂壳纤毛虫的丰度、生物量和种丰富度.调查发现砂壳纤毛虫7属, 22种, 南海新纪录7种;其中Tintinnopsis(拟铃虫)最多, 共10种, Codonellopsis(类铃虫)次之, 共6种.砂壳纤毛虫总丰度为0-41 768ind·m-3, 平均为(2 851±7 244)ind·m-3, 生物量为0-609.92mg·m-3(以碳含量计算,下同),平均为(42.75±110.80)mg·m-3;76.83%站位的砂壳纤毛虫丰度低于 1 000ind·m-3.砂壳纤毛虫生物量与丰度分布的总体趋势为近岸高且站位间差异大, 远洋低且站位间差异小.所采集种类集中分布于雷州半岛以东的近岸浅水区, 此区水文状况为高温低盐, 高叶绿素a浓度(Chl a);不同种的分布规律不同, 多呈斑块状分布.各站位种的丰富度为0-12, 水平分布呈现近岸高远岸低的规律;砂壳纤毛虫的丰度、生物量以及种丰富度与Chl a浓度均为正相关关系;Tintinnopsis schotti和Tintinnopsis radix为优势种.     

桑沟湾浮游纤毛虫丰度和生物量分布的季节变化

于2011年4、8、10月及2012年1月对桑沟湾进行了浮游纤毛虫丰度和生物量的季节调查。纤毛虫的平均丰度为(7 552±10 979)个/L,范围为408~61 667个/L;纤毛虫的平均生物量(以碳计)为(4.79±5.77)μg/L,范围为0.35~33.09 μg/L。无壳纤毛虫丰度和生物量主要分布在湾内,湾中和湾外丰度相对较低;砂壳纤毛虫丰度和生物量在盐度较高的海区总体较高,呈现朝向外海分布的趋势。纤毛虫丰度和生物量的高值区春季主要出现在湾的西北,夏季向湾中部迁移,秋季主要出现在湾的西南,冬季主要出现在湾的西部,高值区随季节大致呈顺时针迁移的趋势。纤毛虫的丰度春季最高,冬季最低;生物量夏季最高,冬季最低。无壳纤毛虫夏季粒级较大,冬季粒级较小;砂壳纤毛虫壳的平均口径夏季较大,秋季较小。共鉴定出砂壳纤毛虫8属27种,其中拟铃虫属(Tintinnopsis)种数最多。砂壳纤毛虫在纤毛虫总丰度中的比例平均为16.3%±21.9%,夏季最高(36.3%±27.8%),冬季最低(4.9%±5.9%)。纤毛虫丰度与温度、盐度、Chl a浓度及微微型真核浮游生物丰度均没有明显的相关性,但与蓝细菌及异养细菌丰度呈显著的正相关关系。     

渤海微型浮游动物及其对浮游植物的摄食压力

１９９７年６月在渤海的５个站位采样分析了微型浮游动物的空间分布,用稀释法研究了浮游植物的生长率和微型浮游动物对浮游植物的摄食压力。结果表明,所研究的微型浮游动物主要是砂壳纤毛虫和桡足类幼虫。Ｃｏｄｏｎｅｌｌｏｐｓｉｓ ｓｐｐ．是砂壳纤毛虫的绝对优势种,只在１、３、５号站有分布。表层分布为：１号站９８１ｉｎｄ／Ｌ、５号站２００ｉｎｄ／Ｌ、３号站３０ｉｎｄ／Ｌ;垂直分布为上层多、下层少。桡足类幼虫密度     

胶州湾桡足类幼虫和浮游生纤毛虫的丰度与生物量

1997年9月，12月，1998年2月，4月，8月，11月以及1999年2月和5大以胶州湾采集桡足类幼虫和浮游生纤毛虫的样品，样品用Lugol‘s试剂固定（最后浓度1％），用显微镜计数桡足类幼虫和浮游生纤毛虫的丰度，并计算总生物量（表层生物量和水体生物量）。桡足类幼虫，无壳纤毛虫和砂壳纤毛虫的最大丰度分别为850ind/L(1998年8月），21300ind/L(1998年8月）和172ind／L(1999年5），表层的总丰度为10－22630ind/L，平均分布湾内比湾外多，表层纤毛虫和桡足类幼虫的总生物量为0．10－380.27ugC/L，水体的生物量为0．20－1426.02mgC/m^2.     

Variability in low tide populations of tuatua,Paphies donacina,in Pegasus Bay,Canterbury, New Zealand

Paphies donacina (Spengler, 1793) populations were surveyed at 11 low tide sites on surf beaches along Pegasus Bay, Canterbury, New Zealand, during summer 1998. Random sampling was not feasible. At the non‐random sites chosen the average number of tuatua per 5 m of shoreline ranged between 0.1 and 62. Total wet weight biomass m^‐2 was highest at the southern sites in the Bay. There were site‐related differences in length frequency distributions of tuatua populations. Northern populations included a wide length range and southern populations were dominated by larger bivalves. Average shell length increased significantly with distance south, being close to 40 mm at Waikuku and 80 mm at Taylors Mistake. The shell length: width and weight relationships were similar for tuatua collected over the whole geographic range. Average dry weight condition index varied significantly between sites (ANOVA F= 23.3, d.f. = 10, 329) depending on the length distribution of the contributing population. Where populations included a wide length range the condition index was positively correlated with shell length but in populations dominated by larger bivalves there was either no relationship or a negative relationship with shell length. Juvenile tuatua were found at average densities between 81 and 1200 m^‐2 at all sites except Taylors Mistake. The mean length of recruits ranged from 2.2 to 3.1 mm and shell length was independent of both juvenile and adult density. These results are discussed in relation to the environmental and other factors thought to influence population structure and recruitment of tuatua in Pegasus Bay.     

Distribution, abundance, and growth of larval tautog, Tautoga onitis, in Buzzards Bay, Massachusetts, USA

Tautog, Tautoga onitis, is an abundant species of fish in estuaries of the northeastern United States. Planktonic tautog larvae are abundant in summer in these estuaries, but there is little information on rates of growth of tautog larvae feeding on natural assemblages of food in the plankton. We examined abundance and growth of larval tautog and environmental factors during weekly sampling at three sites along a nearshore‐to‐offshore transect in Buzzards Bay, Massachusetts, USA during summer 1994. This is the first study of a robust sample size (336 larvae) to estimate growth rates of field‐caught planktonic tautog larvae feeding on natural diets, using the otolith daily‐growth‐increment method. The study was over the entire summer period when tautog larvae were in the plankton. The sampling sites contrasted in several environmental variables including temperature, dissolved oxygen (DO), and chlorophyll a concentration. There was a temporal progression in the abundance of tautog larvae over the summer, in relation to location and temperature. Tautog larvae were first present nearshore, with a pronounced peak in abundance occurring at the nearshore sites during the last 2 weeks in June. Larvae were absent at this time further offshore. From late June through August, larval abundance progressively decreased nearshore, but increased offshore although never approaching the abundance levels observed at the nearshore sites. The distribution and abundance of tautog larvae appeared to be related to a nearshore‐to‐offshore seasonal warming trend and a nearshore decrease in DO. Otoliths from 336 larvae ranging from 2.3 to 7.7 mm standard length had otolith increment counts ranging from 0 to 19 increments. Growth of larval tautog was estimated at 0.23 mm·day^?1, and length of larvae prior to first increment formation was estimated at 2.8 mm indicating that first increment formation occurs 3–4 days after hatching at 2.2 mm. Despite spatial and temporal differences in environmental factors, there were no significant differences in growth rates at any of three given sites over time, or between sites. Because larval presence only occurred at a narrow range of temperature (17–23.5 °C) and DO (6.5–9.3 mg·l^?1), in situ differences in growth did not appear to be because of differences in larval distribution and abundance patterns relative to these parameters.     

Cadmium,cobalt, copper,iron, lead,nickel and zinc in Indian Ocean water

Results of trace-metal analyses of water samples obtained during a cruise with the Soviet R.V. “Akademik Kurchatov” in the Indian Ocean are presented. The determinations were performed on board with atomic absorption spectrophotometry after a two-stage dithiocarbamate—Freon extraction procedure. Trace-metal concentrations found are in the same range as those found recently for similar open-ocean areas by other workers. The values for lead and zinc are probably high due to contamination. Vertical profiles indicate biogenic processes as controlling factors for the increase of cadmium, copper and nickel concentrations with depth. Iron shows an irregular depth distribution as a result of large random variations in concentration.     

Arsenic,barium, germanium,tin, dimethylsulfide and nutrient biogeochemistry in Charlotte Harbor,Florida, a phosphorus-enriched estuary

Concentrations of dissolved nutrients (NO₃, PO₄, Si), germanium species, arsenic species, tin, barium, dimethylsulfide and related parameters were measured along the salinity gradient in Charlotte Harbor. Phosphate enrichment from the phosphate industry on the Peace River promotes a productive diatom bloom near the river mouth where NO₃ and Si are completely consumed. Inorganic germanium is completely depleted in this bloom by uptake into biogenic opal. The $\text{Ge}\text{Si}$ ratio taken up by diatoms is about 0·7 × 10^?6, the same as that provided by the river flux, confirming that siliceous organisms incorporate germanium as an accidental trace replacement for silica. Monomethylgermanium and dimethylgermanium concentrations are undetectable in the Peace River, and increase linearly with increasing salinity to the seawater end of the bay, suggesting that these organogermanium species behave conservatively in estuaries, and are neither produced nor consumed during estuarine biogenic opal formation or dissolution. Inorganic arsenic displays slight removal in the bloom. Monomethylarsenic is produced both in the bloom and in mid-estuary, while dimethylarsenic is conservative in the bloom but produced in mid-estuary. The total production of methylarsenicals within the bay approximately balances the removal of inorganic arsenic, suggesting that most biological arsenic uptake in the estuary is biomethylated and released to the water column. Dimethylsulfide increases with increasing salinity in the estuary and shows evidence of removal, probably both by degassing and by microbial consumption. An input of DMS is observed in the central estuary. The behavior of total dissolvable tin shows no biological activity in the bloom or in mid-estuary, but does display a low-salinity input signal that parallels dissolved organic material, perhaps suggesting an association between tin and DOM. Barium displays dramatic input behavior at mid-salinities, probably due to slow release from clays deposited in the harbor after catastrophic phosphate slime spills into the Peace River.     

Fisheries privatization,social transitions,and well-being in Kodiak,Alaska

Scholars and fishermen alike view the privatization of fishing rights as a fundamental driver of social change in fishing communities. This article presents the results of a mixed-methods ethnographic study in Kodiak, Alaska, exploring how fisheries privatization processes remake fishery systems. Findings from this study suggest that a diverse range of fishery participants share core values about the social dimensions of fishery systems. Support or opposition to past privatization processes tended to be articulated in reference to how these core values (e.g., hard work, opportunity, and fairness) were perceived to have been strengthened or eroded by such processes. Data from this study suggest that while still widespread in the Kodiak fishing community, core social values in fishing may be changing as a result of privatization processes. Although ethnographic and survey data showed a range of perspectives on the effects of privatization on fishing and the Kodiak community, study participants tended to talk about privatization as a significant change that had divisive, negative impacts in the community. Crew members and the next generation of fishermen were identified as disproportionately affected by privatization processes. Ethnographic data detail important shifts in the power, status, and livelihoods of crew members. Nearly all Kodiak fishery participants interviewed expressed concern about the future of fisheries access in the community for the next generation, in large part because of the substantial financial barriers to entry generated by privatization of fisheries access. Many discussed the need for more entry-level opportunities necessary for access in all fisheries.     

Determination of Na,K, Mg,Ca, Fe,and Mn in organic particulate matter in seawater by atomic absorption

A method for the determination by atomic absorption spectrophotometry of six major inorganic components of the organic particulate matter in seawater is described. Particles were formed by shaking aliquots of filtered seawater. The yield of aggregates varied greatly in replicate samples. The major factors in the variability of the analyses are the high and variable filter blank values for the elements of interest.     

Submerged vegetation of Lakes Sumner,Marion, Katrine,Taylor, and Sheppard in Canterbury,New Zealand

The submerged vegetation of Lakes Sumner, Marion, Katrine, Taylor, and Sheppard was surveyed in May 1987. These high‐altitude lakes lie at c. 600 m a.s.l., within the largely unmodified upper Hurunui catchment. Submerged vegetation was diverse and included numerous short shallow‐water species, dense swards of Isoetes alpinus, low covers of taller native vascular plants, and charophyte meadows beyond the depth limit of vascular plants to a maximum of 15 m. A sparse deepwater bryophyte community was observed from 11 to 32 m depth in Lake Sumner. Displacement of native vegetation by dense growths of the adventive oxygen weed Elodea canadensis over mid‐depths of 3–6 m was noted in all lakes, except Lake Marion.     

Abundance, Biomass, Production and Trophic Roles of Micro- and Net-Zooplankton in Ise Bay, Central Japan, in Winter

We investigated the geographical variations in abundance and biomass of the major taxonomic groups of micro- and net-zooplankton along a transect through Ise Bay, central Japan, and neighboring Pacific Ocean in February 1995. The results were used to estimate their secondary and tertiary production rates and assess their trophic roles in this eutrophic embayment in winter. Ise Bay nourished a much higher biomass of both micro- and net-zooplankton (mean: 3.79 and 13.9 mg C m^–3, respectively) than the offshore area (mean: 0.76 and 4.47 mg C m^–3, respectively). In the bay, tintinnid ciliates, naked ciliates and copepod nauplii accounted for, on average, 69, 18 and 13% of the microzooplankton biomass, respectively. Of net-zooplankton biomass, copepods (i.e. Acartia, Calanus, Centropages, Microsetella and Paracalanus) formed the majority (mean: 63%). Average secondary production rates of micro- and net-zooplankton in the bay were 1.19 and 1.87 mg C m^–3d^–1 (or 23.1 and 36.4 mg C m^–2d^–1), respectively, and average tertiary production rate of net-zooplankton was 0.75 mg C m^–3d^–1 (or 14.6 mg C m^–2d^–1). Available data approximated average phytoplankton primary production rate as 1000 mg C m^–2d^–1 during our study period. The transfer efficiency from primary production to zooplankton secondary production was 6.0%, and the efficiency from secondary production to tertiary production was 25%. The amount of food required to support the zooplankton secondary production corresponded to 18% of the phytoplankton primary production or only 1.7% of the phytoplankton biomass, demonstrating that the grazing impact of herbivorous zooplankton was minor in Ise Bay in winter.     

The behavior of Zn,Cd, Cu,Ni, Co,Fe, and Mn in anoxic baltic waters

In June 1981, dissolved Zn, Cd, Cu, Ni, Co, Fe, and Mn were determined from two detailed profiles in anoxic Baltic waters (with extra data for Fe and Mn from August 1979). Dramatic changes across the O₂H₂S interface occur in the abundances of Cu, Co, Fe, and Mn (by factors of ?100). The concentrations of Zn, Cd, and Ni at the redox front decrease by factors between 3 to 5.Equilibrium calculations are presented for varying concentrations of hydrogen sulfide and compared with the field data. The study strongly supports the assumption that the solubility of Zn, Cd, Cu, and Ni is greatly enhanced and controlled by the formation of bisulfide and(or) polysulfide complexes. Differences between predicted and measured concentrations of these elements are mainly evident at lower ΣH₂S concentrations.Cobalt proved to be very mobile in anoxic regions, and the results indicate that the concentrations are limited by CoS precipitation. The iron (Fe²⁺) and manganese (Mn²⁺) distribution in sulfide-containing waters is controlled by total flux from sediment-water interfaces rather than by equilibrium concentrations of their solid phases (FeS and MnCO₃). The concentrations of these metals are therefore expected to increase with prolonged stagnation periods in the basin.