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1.
Fecal indicator bacteria (FIB) were measured approximately 5 days a week in ankle-depth water at 19 surfzone stations along Huntington Beach and Newport Beach, California, from 1998 to the end of 2003. These sampling periods span the time before and after treated sewage effluent, discharged into the coastal ocean from the local outfall, was disinfected. Bacterial samples were also taken in the vicinity of the outfall during the pre- and post-disinfection periods. Our analysis of the results from both data sets suggest that land-based sources, rather than the local outfall, were the source of the FIB responsible for the frequent closures and postings of local beaches in the summers of 2001 and 2002. Because the annual cycle is the dominant frequency in the fecal and total coliform data sets at most sampling stations, we infer that sources associated with local runoff were responsible for the majority of coliform contamination along wide stretches of the beach. The dominant fortnightly cycle in enterococci at many surfzone sampling stations suggests that the source for these relatively frequent bacteria contamination events in summer is related to the wetting and draining of the land due to the large tidal excursions found during spring tides. Along the most frequently closed section of the beach at stations 3N-15N, the fortnightly cycle is dominant in all FIBs. The strikingly different spatial and spectral patterns found in coliform and in enterococci suggest the presence of different sources, at least for large sections of beach. The presence of a relatively large enterococci fortnightly cycle along the beaches near Newport Harbor indicates that contamination sources similar to those found off Huntington Beach are present, though not at high enough levels to close the Newport beaches. 相似文献
2.
秦山核电站邻近水域大肠菌群和粪大肠菌群的分布 总被引：1，自引：0，他引：1
本文对秦山核电站邻近水域表层海水中大肠菌群和粪大肠菌群的分布作了春、夏、秋、冬四季的初步调查分析。结果表明,大肠菌群和粪大肠菌群的分布范围为0～3500个/dm~3,并在一年四季中都能检出大肠菌群和粪大肠菌群。其分布趋势为沿岸高于外侧,退潮大于涨潮,南部多于北部。细菌的数量随水温、盐度、潮汐等环境因子的变化而变化。 相似文献
3.
Hueiwang Anna C. Jeng Andrew J. Englande Reda M. Bakeer Henry B. Bradford 《Estuarine, Coastal and Shelf Science》2005,63(4):513-526
Urban stormwater runoff could contribute to the deterioration of water quality of a receiving water body. In this research, field studies and laboratory experiments were conducted to assess the microbial contamination resulting from urban stormwater runoff into the Lake Pontchartrain estuary. Fecal coliform, Escherichia coli and enterococci were used as indicator organisms. The specific objectives of the research were to examine the distribution of the indicator organisms in different environmental elements (water column, suspended particles and sediment) and to further investigate the mechanisms related to their fate. Results of the research indicated satisfactory water quality at the study sites during dry weather periods. However, a significant increase was observed in the concentrations of the indicator organisms in the water columns and sediment at specific study sites following a given stormwater event. Three to seven days were needed for the elevated indicator organisms to return back to their background levels in the water column and sediment, respectively. The mechanism of sedimentation contributed to a reduction in the microbial concentration in the water column, as the indicator organisms were found to attach to the suspended particles in the stormwater. The percentage of fecal coliform, E. coli and enterococci attached to the suspended particles was found to be within the range of 9.8–27.5%, 21.8–30.4%, and 8.4–11.5% of the total indicator organisms in the stormwater loaded into the estuary, respectively. About 75–80% of the total indicator organisms remained free-floating for some distance in the water column before dying off. 相似文献
4.
中国重点海水浴场中粪肠球菌和主要肠道病毒的调查研究 总被引：1，自引：0，他引：1
本文调查了中国十大典型海水浴场,旨在监测人类肠道病毒在海水浴场的发生情况,并且找出表面海水中肠道病毒的存在与传统的粪便污染指示物一粪大肠菌群是否存在关系,如果存在,是什么关系。分别采用常规的平板计数法和RT-PCR技术对粪大肠菌群和人类致病性的主要肠道病毒（甲肝病毒、轮状病毒、脊髓灰质炎病毒）进行了检测。结果显示,在2... 相似文献
5.
大肠菌群寄居于人和其他温血动物的肠道之中，是其粪便中的主要细菌，应用大肠菌群作为饮用水的卫生质量和是否受粪便污染的指示生物，已有较长历史。目前已逐渐建立起一整套比较成熟的确定样品中大肠菌群密度的方法，这些方法已公认为对不同用途水的卫生质量进行细菌学检验的标准方法( A. P. H. A., A. W.W. A. & W. P. C. F，1971)。
大量调查研究结果表明，生活污水中存在着数量惊人的肠道类细菌。这些肠道类细菌随污水进入海洋后，由于环境条件的骤然改变，以及海洋微生物的拮抗作用和抗菌素的产生，它们会在短时间内大量死亡(Jones, 1971; Lessard & Sieburth, 1983；钱振儒、张景镛，1985a, 1985b)。然而，仍有一定数量的肠道类细菌能在海水里存活一段时间，特别是在有机物质含量丰富的污染海水中，其存活时间更长些(薛廷耀，1962)。
所以，在海洋环境污染的监测和评价中，尤其对河口近岸水域以及养殖水体、海水浴场的污染监测和评价时，把海水的大肠菌群密度作为一项监测和评价项目，不仅是可能的，而且也是必要的。为此，世界多数国家己作了明确规定，一般海水每升水样中大肠菌群数不得超过10000个(此标准也适用于与人体直接接触的浴场海水)，而养殖水体则每升不得超过700个。我国也作了同样的规定。但是在我国海洋环境污染监测和评价的实际工作中，运用生物监测手段的工作，包括大肠菌群的监测，不仅做得不多，而且尚未受到普遍重视。
本文是1984年海河口区有机污染现状调查和评价中有关大肠菌群数量分布及其与水域有机污染程度相关分析的总结，试图通过海河口区这一典型实例，来论证大肠菌群作为河口海域有机污染的指示生物是完全可行的。 相似文献
6.
黄河口悬浮泥沙时空动态及其驱动机制 总被引：1，自引：1，他引：0
受径流输沙、风浪、潮汐等影响,河口近岸海域悬浮泥沙具有显著的时空变化。本文基于小时分辨率的GOCI遥感影像,利用最优遥感反演算法,结合空间分析和统计方法,深入研究黄河口及邻近海域悬沙时空动态特征及驱动机制。结果表明,径流输沙对悬沙浓度的影响以河口近岸区为主,高径流输沙对悬沙浓度分布影响可达距岸约20 km,并向孤东近岸方向扩散。大风可引起清水沟老河口区泥沙强烈再悬浮,形成高浓度悬沙区。涨落潮对小时尺度的悬沙浓度影响显著,并影响悬沙的南北扩散。大潮悬沙浓度变化和扩散范围均大于小潮,潮流流速不同是造成该差异的主要原因。水深与悬沙浓度之间存在较明显的负相关关系,根据不同驱动因素的差异,悬沙浓度随着水深的增加呈现出指数型、幂函数型、线性3种关系。 相似文献
7.
The New Zealand Waters Pollution Regulations 1963, referring to recreational water to which the public can gain access, states that the “coliform bacteria content shall not consistently exceed 1,000/100 ml”. This standard is now under revision, and the suggested new standard is a median faecal coliform index of 200/100 ml with a maximum value not exceeding 400/100 ml. Recent literature supports the use of faecal coliform sub‐group bacteria as the best indicator of faecal pollution and reference is made to the membership of this sub‐group. Inherent inaccuracies of the Most Probable Number (MPN) method of assessing bacterial populations are pointed out, such as experimental variations with different cultural media, and possible errors in interpretation of results. In North America, there is evidence that an MPN for the total coliform group of 1000/100 ml indicates a faecal coliform sub‐group MPN of 200/100 ml, and epidemiological experience supports these values as standards. We tabulate and discuss evidence that the usual ratio of faecal coliforms : coliform group bacteria is typically 1 : 1 in fresh and marine waters of the Wellington region, and that a more attainable standard would be 500 faecal coliforms/100 ml. In ratios quoted in this paper, ‘coliform group’ means the remainder of the coliform group excluding faecal coliforms. The World Health Organisation (1963) definition, of the entire group of coliforms, is not intended. The ratio is different in other parts of New Zealand; in Auckland, for example, the ratio is close to that found in the United States. 相似文献
8.
收集2000—2018 年福建近岸海域224 次赤潮事件资料，通过综合分析结果表明：2000—2018 年福建近岸海域赤潮发现数量和面积分别占全国的17.3%和6.1%。2015—2018 年相对于2000—2004、2005—2009、2010—2014 年赤潮年均发现数量和面积有明显下降。赤潮发现月份和空间特征明显，5—6 月为高发期；宁德、福州、平潭、厦门、泉州海域是赤潮高发区；4 个时间段比较宁德和厦门海域年均发现赤潮数量下降明显，平潭海域略微下降，泉州海域增加。由甲藻门生物引发的赤潮数量、面积和损失均最高，诱发赤潮的生物类群存在南北差异，有毒赤潮占总赤潮数量的14.3%。根据提出的赤潮等级划分标准，福建近岸海域以小型赤潮为主。建议在宁德至平潭近岸海域、泉州近岸海域加强赤潮立体化监测系统的建设，5—6 月为监测的关键时期。 相似文献
9.
胶州湾是我国沿海的一个重要港湾,长期以来对其进行了较多的调查研究工作。大港验潮站自1926年起开始观测(1936-1946年曾中断),目前已积累了44年的长期水位资料。山角底验潮站自1967年开始观测,也积累了16年的水位资料。我们还系统地搜集了我所1958-1959年在薛家岛、东洋嘴、团岛、麦岛、大公岛分别进行的四个月、两个月及半个月的观测资料,以及山东海洋学院1975年在红岛船厂(阴岛)、黄岛客运码头分别进行的三个月及两个月的水位观测资料和团岛湾、后岔湾、大石头等地的潮汐调和常数。此外,我们还搜集了胶州湾及其附近海区共二十三个测站的海流连续观测资料,其中十九个站的资料是由我所在1957-1959年观测的,三个站是1982年“全国海岸带调查”中测得的,另一个站是华东水利学院提供的资料。这些测站,除六个站为一昼夜连续观测外,其余十七个站均为二昼夜以上连续观测(有一个站为十五昼夜连续观测)。观测站位见图1。
我们把搜集到的这些潮汐、潮流资料进行了调和分析,得到了各主要分潮的调和常数及潮汐、潮流特征值。本文以此为基础,结合实测资料,分析了胶州湾潮汐、潮流的基本特征。 相似文献
10.
The Changjiang River diluted water(CDW) spreads into the East China Sea(ECS) primarily in a plume pattern,although in some years, low-salinity water lenses(LSWLs) detach from the main body of the CDW. In-situ observations indicate that in August 2006, a LSWL detached from the main body of the CDW near the river mouth.In this paper, the effects of winds, tides, baroclinity and upwelling on LSWLs are explored with a threedimensional model. The results show that:(1) winds play a crucial role in these detachment events because windinduced northerly Eulerian residual currents impose an uneven force on the CDW and cut it off, thus forming a LSWL;(2) upwelling carries high-salinity water from the lower layer to the upper layer, truncating the low-salinity water tongue vertically, which is conducive to the detachment and maintenance of LSWLs; and(3) upwelling during the evolution of a LSWL is caused by the combined effects of winds and tides. The influences of windinduced upwelling are mainly near the shore, whereas the upwelling along the 30 m isobath is predominantly affected by tides, with the effect increasing from neap tide to spring tide. 相似文献
11.
Joanna Burger 《Estuarine, Coastal and Shelf Science》1983,16(2):191-216
The distribution and abundance of gulls were examined at Jamaica Bay Wildlife Refuge (New York) from 31 May 1978 to 31 May 1979. Gulls were found to be affected by tidal, temporal and weather-related factors. The distribution of gulls was affected primarily by tidal factors on the bay, and by temporal (seasonal, circadian) and weather-related factors on the freshwater ponds. The most important weather-related factors were temperature, wind velocity and wind direction. Herring (L. argentatus), great black-backed (L. fuscus) and ring-billed gulls (L. delawarensis) fed on the bay at low tides, and used the ponds at high tide. Laughing gulls (L. atricilla) fed on the bay at low tide and on rising tides. Herring and great black-backed gulls were present all year, but were most abundant in the winter, ring-billed gulls were abundant in spring and early fall, and laughing gulls were present in the summer following the breeding season but were absent in winter. Gulls used the ponds during high velocity, north winds, when they usually rested or preened. Multiple regression models were used to determine the factors explaining the variability in the numbers of gulls. Temporal variables were important contributors to accounting for the variability in the numbers of great black-backed and herring gulls only; tidal variables were significant for great black-backed and herring gulls on the bay, and for ring-billed and laughing gulls on all areas; and weather variables were significant for all species. 相似文献
12.
We have examined the vertical distributions of planktonic bivalve larvae, particularly the clam Ruditapes philippinarum and the mussel Musculista senhousia which are common and abundant on tidal flats of eastern Ariake Bay, southern Japan. Submersible pumping gear was used to
take samples at 2 stations every 2 hours during the spring tide over a whole tidal cycle and/or through daytime and nighttime.
Water samples were pumped up from 3 to 5 depths from the surface to sea bottom. Regardless of tidal cycles, D-shaped larvae
were concentrated near the surface, while umbo larvae were found at the surface to intermediate depths. On average, these
larval densities were significantly higher at the station close to the shore than the offshore station, with no significant
difference between daytime and nighttime and between flood and ebb tides at each station. The velocity and direction of water
movement at both stations revealed remarkable difference between the surface and bottom waters. The larvae at the surface
may quickly disperse and be transported elsewhere, while those in water close to the sea bottom may tend to be retained. 相似文献
13.
Ecosystem management and decision making process are dependent of a good knowledge of ecosystem functioning. Conceptual models allow knowledge organization through representation of relationships between variables and processes, facilitating management decisions. In this study, spatial and temporal characterization of key environmental variables, as well as relationships between them, was studied aiming the design of a conceptual model of the Douro estuary. This temperate mesotidal estuary is limited upstream by a hydroelectric power dam that controls freshwater inflow and prevents the propagation of the tide upstream, which, in turn, influences water circulation and biogeochemical dynamics of the system. During one year, from December 2002 to December 2003, water column data were collected monthly at 10 stations along the estuary, during ebb and flood tides. Spatial and temporal variability of water column salinity, temperature, nutrients, phytoplankton biomass, total particulate matter (TPM), phytoplankton primary production (PP), faecal coliform bacteria (FC) and community respiration (CR) were analysed. Salinity stratification was assessed by means of the Estuary Number (Ne) and variation of this index as well as other key characteristics with river flow was analysed. Freshwater discharge controlled salinity stratification and freshwater residence time. Ne indicated that the Douro was stratified for river flows <300 m3 s−1, and freshwater residence time was >1 day for the same conditions. A decaying exponential relationship between PP and river flow was found, whereas nitrate and TPM increased logarithmically and linearly, respectively, with river flow. Regarding spatial distribution, nitrate and PP decreased downstream, showing that the river was a source of nutrients and phytoplankton, while the opposite trend was found for TPM, FC, ammonium and CR. The latter increase was probably due to untreated sewage discharge in the urbanized middle and lower estuarine stretches. Reduction of nitrate coming from the watershed and of bacterial contamination in the urban stretches of this highly modified water body, according to the European Water Framework Directive, emerges as the main water quality issues for this estuarine ecosystem. 相似文献
14.
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15.
Underwater video reveals decreased activity of rocky intertidal snails during high tides and cooler days 
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下载免费PDF全文 Nearly all of our understanding of rocky inter‐tidal ecology comes from studies conducted at low tide. To study inter‐tidal organisms at high tide, we anchored waterproof digital GoPro® video cameras in wave‐exposed tidepools and recorded the daytime movements of the black turban snail, Tegula funebralis, over the tidal cycle between May and August 2012 near Bodega Bay, California. Overall, snails moved more quickly and presumably foraged more during low tides and on days with warmer air and perhaps water temperatures. This is similar to other ectotherms that exhibit increased metabolic rates, movement and foraging in warmer conditions. Snails also moved less during flood and high tides, may have moved downward in tidepools at flood tides, and showed evidence of reduced activity on days with larger waves. This inactivity and refuge seeking may have been a strategy to avoid dislodgment by waves. Analysis of snail trajectories showed foraging bouts indicated by alternating zig‐zagging and straight movement. There was no effect of temperature, wave height, or tidal phase on distribution of snail turning angles, suggesting that they may have foraged consistently but moved faster during warm conditions and low tides, thereby grazing a larger area. This is one of few direct recordings of inter‐tidal organisms on wave‐exposed rocky shores during high tide. The methods used here are easily transferable to other studies, which are needed to increase our understanding of behaviors that structure rocky shore communities during high tide. 相似文献
16.
文章采用三维海洋模式MITgcm, 对印度尼西亚海(简称印尼海)内潮的生成和传播过程进行了研究。研究结果表明: 1)苏拉威西海和西北太平洋地区的内潮呈现明显的全日潮信号; 望加锡海峡、翁拜海峡、东北印度洋、帝汶海等站位的内潮呈现明显的半日潮信号; 2)印尼海区内潮的标准化振幅在苏拉威西海、望加锡海峡、翁拜海峡、马鲁古海、班达海、东北印度洋和西北太平洋地区均在温跃层附近达到最大, 约为20~40m; 在帝汶海地区在水深200m附近达到最大, 约为25~30m; 3)桑岭、斯兰海、翁拜海峡和帝汶海是主要的内潮生成区域, 内潮能通量达40kW·m-1; 4)苏禄海的内潮能量主要来自于局地正压潮的转化, 苏拉威西海和班达海的内潮能量则主要来自外部的传入。 相似文献
17.
Young Baek Son Joji Ishizaka Jong-Chul Jeong Hyun-Choel Kim Taehee Lee 《Ocean Science Journal》2011,46(4):239-263
To distinguish true red tide water (particularly Cochlodinium polykrikoides blooms) from non-red tide water (false satellite high chlorophyll water) in the South Sea of Korea, we developed a systematic
classification method using spectral information from MODIS level products and applied it to five different harmful algal
bloom events. Red tide and nonred tide waters were classified based on four different criteria. The first step revealed that
the radiance peaks of potential red tide water occurred at 555 and 678 nm. The second step separated optically different waters
that were influenced by relatively low and high contributions of colored dissolved organic matter (CDOM) (including detritus)
to chlorophyll. The third and fourth steps discriminated red tide water from non-red tide water based on the blue-to-green
ratio in areas with lower and higher contributions of CDOM to chlorophyll, respectively. After applying the red tide classification
(using the four criteria), the spectral response of the red tide water, which is influenced by pigment concentration, showed
different slopes for the blue and green bands (lower slope at blue bands and higher slope at green bands). The opposite result
was found for non-red tide water, due to decreasing phytoplankton absorption and increasing detritus/CDOM absorption at blue
bands. The results were well matched with the discoloration of water (blue to dark red/brown) and delineated the areal coverage
of C. polykrikoides blooms, revealing the nature of spatial and temporal variations in red tides. This simple spectral classification method
led to increase user accuracy for C. polykrikoides and non-red tide blooms (>46% and >97%) and provided a more reliable and robust identification of red tides over a wide range
of oceanic environments than was possible using chlorophyll a concentration, chlorophyll anomaly, fluorescence analysis, or proposed red tide detection algorithms. 相似文献
18.
Robert J. Wilcock John W. Nagels Harvey J. E. Rodda Michael B. O'Connor Bruce S. Thorrold James W. Barnett 《新西兰海洋与淡水研究杂志》2013,47(4):683-696
A small stream in a predominantly dairying catchment in the Waikato region of New Zealand was monitored for 2 years at three sites. Total nitrogen (TN) concentrations were up to 7.09 g m‐3 in winter, with the bulk comprising nitrate nitrogen (NO‐ 3‐N). During summer NO‐ 3‐N was near zero and TN mostly comprised organic nitrogen. Maximum concentrations of total phosphorus (TP) and dissolved reactive phosphorus (DRP) were 1.64 and 0.555 g m‐3, respectively, and peaks coincided with spring and autumn applications of phosphorus fertiliser. Ammoniacal nitrogen concentrations exceeded 1 g m‐3 on several occasions and mean concentrations at the three sites were 0.165–0.272 g m‐3. Faecal coliform and enterococci bacteria concentrations were 64–26000 and 7–23000 cfu per 100 ml, respectively. Specific yields of TN and NO‐ 3‐N (35.3 and 30.7 kg ha yr‐1, respectively) were much greater than any previously reported for New Zealand pasture catchments, whereas TP and DRP yields (1.16 and 0.54 kg ha yr‐1, respectively) were more in accord with other studies. Greater use of land treatment of liquid wastes will reduce stream inputs of faecal organisms, NH4‐N and P. 相似文献
19.
Jan Svejkovsky Nikolay P. Nezlin Neomi M. Mustain Jamie B. Kum 《Estuarine, Coastal and Shelf Science》2010
Spatial–temporal characteristics and environmental factors regulating the behavior of stormwater runoff from the Tijuana River in southern California were analyzed utilizing very high resolution aerial imagery, and time-coincident environmental and bacterial sampling data. Thirty nine multispectral aerial images with 2.1-m spatial resolution were collected after major rainstorms during 2003–2008. Utilizing differences in color reflectance characteristics, the ocean surface was classified into non-plume waters and three components of the runoff plume reflecting differences in age and suspended sediment concentrations. Tijuana River discharge rate was the primary factor regulating the size of the freshest plume component and its shorelong extensions to the north and south. Wave direction was found to affect the shorelong distribution of the shoreline-connected fresh plume components much more strongly than wind direction. Wave-driven sediment resuspension also significantly contributed to the size of the oldest plume component. Surf zone bacterial samples collected near the time of each image acquisition were used to evaluate the contamination characteristics of each plume component. The bacterial contamination of the freshest plume waters was very high (100% of surf zone samples exceeded California standards), but the oldest plume areas were heterogeneous, including both polluted and clean waters. The aerial imagery archive allowed study of river runoff characteristics on a plume component level, not previously done with coarser satellite images. Our findings suggest that high resolution imaging can quickly identify the spatial extents of the most polluted runoff but cannot be relied upon to always identify the entire polluted area. Our results also indicate that wave-driven transport is important in distributing the most contaminated plume areas along the shoreline. 相似文献
20.
In order to determine the temporal and spatial variations of nutrient profiles in the shallow pore water columns (upper 30
cm depth) of intertidal sandflats, we measured the salinity and nutrient concentrations in pore water and seawater at various
coastal environments along the southern coast of Korea. In the intertidal zone, salinity and nutrient concentrations in pore
water showed marked vertical changes with depth, owing to the active exchange between the pore water and overlying seawater,
while they are temporally more stable and vertically constant in the sublittoral zone. In some cases, the advective flow of
fresh groundwater caused strong vertical gradients of salinity and nutrients in the upper 10 cm depth of surface sediments,
indicating the active mixing of the fresher groundwater with overlying seawater. Such upper pore water column profiles clearly
signified the temporal fluctuation of lower-salinity and higher-Si seawater intrusion into pore water in an intertidal sandflat
near the mouth of an estuary. We also observed a semimonthly fluctuation of pore water nutrients due to spring-neap tide associated
recirculation of seawater through the upper sediments. Our study shows that the exchange of water and nutrients between shallow
pore water and overlying seawater is most active in the upper 20 cm layer of intertidal sandflats, due to physical forces
such as tides, wave set-up, and density-thermal gradient. 相似文献