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1.
Michael Martin Gary Ichikawa Jon Goetzl Margarita de los Reyes Mark D. Stephenson 《Marine environmental research》1984,11(2):91-110
Resident populations of Mytilus edulis from Tomales and San Francisco Bay, California, were measured for scope of growth, a physiological integration of the energy consumed by individual animals (feeding rate and assimilation efficiency) less the energy lost in metabolic processes (oxygen consumption and ammonia excretion). Scope for growth of mussels was significantly correlated (p≤ 0·05) with feeding rates. There was a significant decline in the scope for growth between the Golden Gate, at the bay's entrance and RedwoodCity in south San Francisco Bay. The scope for growth in resident M. edulis was significantly negatively correlated (p≤ 0·05) with increased environmental concentrations (from transplanted M. californianus body burden data) of the following trace elements and higher molecular weight chlorinated organic compounds: Cr, Cu, Hg (p ≤ 0·01) and Ag, Al, Zn, total chlordanes, and dieldrin. Scope for growth was significantly correlated (p ≤0·05) with body condition index (dry body weight1shell length). 相似文献
2.
M.S Harakeh Aftim Acra May Jurdi Yester Karahagopian 《Marine environmental research》1985,16(1):13-22
The muscle tissue of 266 fish caught along the coast of Lebanon from Beirut to Tyre (85 km) were analysed for total mercury content. The mean levels for the 13 species ranged from 0·028 mg/kg of wet tissue for Siganus rivulatus to 0·0.54 mg/kg for Mullus barbatus. Whereas no significant differences (P < 0·05) in mercury levels were noted between species, in most cases a direct relationship was found between the weight or length of fish of the same species and total mercury content. Similarly, there were no significant differences (P < 0·05) between herbivore and carnivore species, nor between resident and migrant ones. All of the values obtained in the present study fall below the widely accepted limit of 0·5mg/kg of edible tissue. 相似文献
3.
The soft sediment fish communities below 20 m depth were studied at two sites on the west coast of Scotland (Irvine Bay, Firth of Clyde and the Lynn of Lorne) using small meshed beam trawls. In both cases the emphasis was on the small demersal fish (<15 cm) within these communities. The Irvine Bay community was studied between May 1978 and December 1979 and the Lynn of Lorne community between February 1975 and October 1976.Twenty-seven fish species were recorded in Irvine Bay and 32 in the Lynn of Lorne. In both communities four species constituted more than 78% of the total annual abundance, two gobies (Lesueurigobius friesii and Pomatoschistus norvegicus) were high in the dominance ranking for both sites. The species abundance lists were similar for both sites (0·62 level of similarity) but the species lists for each site were different (0·36 level of similarity). The overall mean density of small demersal fish was similar for both sites (Irvine Bay = 0·045 individuals m?2 and the Lynn of Lorne = 0·047 individuals m?2). There were two periods of high abundance for both communities (late autumn to winter and late spring). There was, however, a low repeatability between successive years. The species richness (D) was relatively high (Irvine Bay = 1·5-3·08, Lynn of Lorne = 1·4-3·34) as was the species diversity (H′) (Irvine Bay = 1·17-1·97, Lynn of Lorne = 1·23-1·95). The proportional representation () of each species within the community was greater in Irvine Bay ( = 0·57-0·77) than in the Lynn of Lorne ( = 0·50-0·72). Therefore these two communities of small demersal fish appeared to be similar at the community level but the way in which this was achieved was different. 相似文献
4.
Short-term (6 h) behavioural responses and mortality of Scrobicularia exposed to low concentrations of copper in sea water (31%, S) have been investigated.Scrobicularia can detect copper at a concentration of 0·01 ppm. The initial response is valve closure resulting in a rapid drop in heart rate. In concentrations of 0·05, 0·01 and, to a lesser extent, 0·1 ppm copper added to sea water, the clams begin to interact with the polluted water after 2–3 h. In 0·5 ppm, the valves remain closed and the heart rate is maintained at a low level over the 6-h exposure period.Mortality increases with time in 0·5 ppm copper concentration, reaching 50% in 5–7 days. In 0·05 and 0·01 ppm, no mortality was recorded over this period.There is an increase in mantle cavity water calcium concentration after 6 h in 0·5 ppm, in contrast to 0·1, 0·05 and 0·01 ppm. Aspects of anaerobiosis, accumulation of heavy metals and survival are discussed in relation to the behaviour of Scrobicularia exposed to various copper concentrations. 相似文献
5.
Total mercury concentrations were determined in surficial sediments, eleven species of benthic organisms and six species of fish from Haifa Bay, Israel. The results show that essentially all of the shallow water zone of the Bay receives anthropogenic mercury. A mercury-cell chlor-alkali plant was identified as the source of pollution. Surficial sediments in the vicinity of the plant, containing up to 0·99 μg Hg/g dry weight, were up to 157 times enriched in mercury relative to an unpolluted area. Mercury levels in the benthic organisms reflected the levels in the sediments. Maximal concentrations reaching 38·7 and 18·2 μg Hg/g dry weight were found in the carnivorous gastropod molluscs Arcularia circumcinta and Arcularia gibbosula, respectively. In all fish species, specimens caught in Haifa Bay had higher mercury concentrations in the muscle tissue than specimens caught south of the Bay. A maximal value of 1·66 μg Hg/g wet weight was recorded in Diplodus sargus. 相似文献
6.
Concentrations of zinc, manganese, copper, cadmium, magnesium and iron in three species of red, four species of brown and three species of green macroalgae, and also in sea water have been determined at two localities along the coast of Aqaba. Significant differences in metal concentrations were found between the various species (P<0·01). Similar significant differences were found with regard to different metals (P<0·001). Concentration factors ranged between 102 for Cd and 9·2 × 104 for Fe. The difference in levels of metals between the two localities, however, was not significant (P > 0·05). Of the three groups of algae examined, rhodopytes exhibited the highest concentration power of metals. 相似文献
7.
Ichthyoplankton and microzooplankton were collected twice monthly for one year at a single station in Biscayne Bay, Florida. Based on approximate 10-m3, 333-μm mesh bongo net samples, the mean annual densities were 17·7 m?3 and 1·8 m?3 for fish eggs and larvae, respectively. Ichthyoplankton was most abundant in spring-summer. The most common fish larvae were bay anchovy (Anchoa mitchilli), spotted dragonet (Callionymus pauciradiatus), thread herring (Opisthonema oglinum) and gobies (Gobiidae), which comprised 50% of all larvae collected. A comparison of 35-μm and 333-μm mesh, bongo net collections revealed that mean densities of fish larvae were 8·5 times higher in the smaller mesh. The most abundant microzooplankton, based on 35-μm bongo net collections, were copepod nauplii, <100 μm in width, which averaged 90·41?1 and tintinnids which averaged 168·51?1. The mean density of microzooplankton <100 μm wide, potentially suitable food for first-feeding fish larvae, was 104·91?1, exclusive of tintinnids, and 273·41?1 including tintinninds. Excepting tintinnids, seasonal variability in microzooplankton abundance was low relative to that for ichthyoplankton. High microzooplankton densities, combined with low seasonal variability, indicated that feeding conditions for fish larvae were usually good in Biscayne Bay. Copepods, especially nauplii, were the predominant food of fish larvae (71% of all food items). Only mollusc veliger larvae (18% of all food items) were highly preferred prey but they were a small component of most larval fish diets. Average width of prey eaten by first-feeding larvae was 74 μm. Prey size increased in relation to larval length. 相似文献
8.
The habitat characteristics and spatial segregation of the two common gobies Gobius fallax Sarato, 1889 and Gobius auratus Risso, 1810 were investigated by fish frequency and abundance estimates through visual counts in the northern Adriatic Sea. The latter species is represented by a recently described, unusual colour morph in the northern Adriatic Sea. Gobius fallax was observed at five of the nine locations examined and its abundance did not differ between two of three transect locations at Piran (Slovenia) and at the western coast of Cres (Kvarner region, Croatia). Gobius auratus was not found in the Gulf of Trieste but was present at several Kvarner locations, and co‐occurred with G. fallax at one location at Cres. Both inhabit rocky substrates but they show different preferences for substrate inclinations and bathymetric segregation. Gobius fallax was most frequent between 2 and 8 m depth and was most abundant on substrate inclining less than 30°. Its highest abundance over entire transects was 0.3 indiv.·m?2 but within certain transect sections this increased to 1.25 indiv.·m?2. Gobius auratus attained its highest abundance in depths below 8 m and at substrate inclinations between 30 and 90°. This species attained its highest values at the western coast of Cres, where it reached a maximum of 1.5 indiv.·m?2 over entire transects but even up to 3.0 indiv.·m?2 in certain transect sections. At Krk, the maximum abundance over entire transects was only 0.3 indiv.·m?2. 相似文献
9.
Measurements were made of chlorophyll-a and phaeophytin-a in calcareous sediments along transects off the east coast of Florida (75–190 m) and the west coast of Grand Bahama Island (170–300 m). Solvent partitioning showed that chlorophyll-a concentrations never exceeded 0·1 mg m?2 at either location, most as degradation products. Total pigment concentrations (chlorophyll and phaeopigments) ranged from 0·18–1·83 mg m?2 in sediments off Grand Bahama Island and 2·50 to 20·65 mg m?2 off West Palm Beach. Pigments, expressed per gram dry weight of sediments, increased with depth across the Florida Continental Shelf. This is probably due to differences in sediment character between near-shore and off-shore sediments. 相似文献
10.
The effects of ozone-produced oxidants (OPO) on three developmental stages of the American oyster, Crassostrea virginica, were evaluated. Both straight-hinge (48-h post fertilisation) and setting pediveliger larvae were exposed to a series of OPO concentrations ranging from 0·05 to 0·30 mg/litre OPO (as total residual chlorine) at 25°C for 96 h. Mortality was used as the response parameter and results were quantitatively compared with the effects of chlorine-produced oxidants (CPO) obtained from the literature on these same developmental stages. Adult oysters (2- to 4-year class) were exposed to OPO concentrations ranging from 0·01 to 0·50 mg/litre at 15°C for 5 days and to the same concentration range at 25°C for two consecutive 6-day periods. Shell deposition and faecal matter accumulation were used as the response parameters for this stage.Straight-hinge larvae were significantly more sensitive to OPO than setting pediveliger larvae. Both larval stages were significantly more sensitive to CPO than to OPO. Shell deposition was significantly inhibited at all OPO concentrations for both 15°C and 25°C acclimated adult oysters. No significant differences were found between the shell deposition response of oysters at the two acclimation temperatures. Faecal matter accumulation was significantly reduced at OPO concentrations ≥ 0·05 mg/litre at both 15°C and 25°C. It was significantly (p < 0·05) greater for 25°C acclimated oysters than for 15°C acclimated oysters at OPO concentrations < 0·10 mg/litre but not at higher concentrations. 相似文献
11.
We assessed spatial and temporal variability in the physical environment of a subarctic estuary, and examined concurrent patterns of chlorophyll α abundance (fluorescence), and zooplankton and forage fish community structure. Surveys were conducted in lower Cook Inlet, Alaska, during late July and early August from 1997 through 1999. Principle components analysis (PCA) revealed that spatial heterogeneity in the physical oceanographic environment of lower Cook Inlet could be modeled as three marine-estuarine gradients characterized by temperature, salinity, bottom depth, and turbidity. The gradients persisted from 1997 through 1999, and PCA explained 68% to 92% of the variance in physical oceanography for each gradient-year combination. Correlations between chlorophyll α abundance and distribution and the PCA axes were weak. Chlorophyll was reduced by turbidity, and low levels occurred in areas with high levels of suspended sediments. Detrended correspondence analysis (DCA) was used to order the sample sites based on species composition and to order the zooplankton and forage fish taxa based on similarities among sample sites for each gradient-year. Correlations between the structure of the physical environment (PCA axis 1) and zooplankton community structure (DCA axis 1) were strong (r = 0.43-0.86) in all years for the three marine-estuarine gradients, suggesting that zooplankton community composition was structured by the physical environment. The physical environment (PCA) and forage fish community structure (DCA) were weakly correlated in all years along Gradient 2, defined by halocline intensity and surface temperature and salinity, even though these physical variables were more important for defining zooplankton habitats. However, the physical environment (PCA) and forage fish community structure (DCA) were strongly correlated along the primary marine-estuarine gradient (#1) in 1997 (r = 0.87) and 1998 (r = 0.82). The correlation was poor (r = 0.32) in 1999, when fish community structure changed markedly in lower Cook Inlet. Capelin (Mallotus villosus), walleye pollock (Theragra chalcogramma), and arrowtooth flounder (Atheresthes stomias) were caught farther north than in previous years. Waters were significantly colder and more saline in 1999, a La Niña year, than in other years of the study. Interannual fluctuations in environmental conditions in lower Cook Inlet did not have substantial effects on zooplankton community structure, although abundance of individual taxa varied significantly. The abundance and distribution of chlorophyll α, zooplankton and forage fish were affected much more by spatial variability in physical oceanography than by interannual variability. Our examination of physical-biological linkages in lower Cook Inlet supports the concept of “bottom-up control,” i.e., that variability in the physical environment structures higher trophic-level communities by influencing their distribution and abundance across space. 相似文献
12.
Resuspension of bottom sediments accounted for 69–92% of mean deposition rates (11·6–69·3 gm?2 day?1) measured at 5 sites in the Peel-Harvey Estuarine System, Western Australia. Deposition rates at all but one of the sites were found to be correlated (P<0·05) with a function of wind combining a fetch factor with the number of hours of winds greater than 5 ms?1 weighted by the third power of wind velocity. The exception was the only site with a cover of benthic algae (Cladophora) during the study. Wind-related resuspension greatly affects the forms and amounts of productivity in this system. 相似文献
13.
Ellen E. Deason 《Estuarine, Coastal and Shelf Science》1982,15(2):121-134
Surveys of the distribution, abundance and size of the ctenophore Mnemiopsis leidyi were carried out in Narragansett Bay, R.I. over a 5-year period, 1975–1979. Yearly variations were observed in time of initiation of the ctenophore increase and maximum abundance. Biomass maxima ranged from 0·2 to 3 g dry weight m?3 at Station 2 in lower Narragansett Bay while maximum abundance varied from 20 to 100 animals m?3. Ctenophores less than 1 cm in length generally composed up to 50% of the biomass and 95% of the numerical abundance during the peak of the M. leidyi pulse. During the 1978 maxima and the declining stages of the pulse each year, 100% of the population was composed of small animals. M. leidyi populations increased earlier, reached greater maximum abundances, and were more highly dominated by small animals in the upper bay than toward the mouth of the bay. The averageclearance rate of M. leidyi larvae feeding on A. tonsa at 22°C was 0·36 l mg?1 dry weight day?1, with apparent selection for nauplii relative to copepodites. Predation and excretion rates applied to ctenophore biomass estimated for Narragansett Bay indicated that M. leidyi excretion is minor but predation removed a bay-wide mean of 20% of the zooplankton standing stock daily during August of 1975 and 1976. Variation in M. leidyi predation at Station 2 was inversely related to mean zooplankton biomass during August and September, which increased 4-fold during the 5-year period. 相似文献
14.
Behavioral responses to chemically dechlorinated seawater were studied using two species of marine fish associated with power plant discharge areas off Southern California. Opaleye (Girella nigricans) neither avoided nor were attracted to chlorinated seawater containing 0·1 mg/liter total residual oxidants (TRO) which had been dechlorinated using equimolar or excess sodium thiosulfate. Blue-banded goby (Lythrypnus dalli) did not avoid dechlorinated seawater initially containing 0·1 or 0·9–1·0 mg/liter TRO. Previously it has been shown that opaleye avoided chlorinated seawater with oxidant concentrations of 0·1 mg/liter and blue-banded gobies avoided 0·9–1·0 mg/liter TRO. Elimination of chlorine-produced oxidants by thiosulphate dechlorination resulted in 100% survival in both species. The toxicological implications of exposure to dechlorinated seawater are discussed. 相似文献
15.
In early summer plaice (Pleuronectes platessa L.) in the Clyde Sea Area eat Tellina siphons and spionid palps. As they grow, they take progressively larger siphons, fragments of spionids and some crustaceans. In late summer they eat entire spionids and other sedentary polychaetes. There is no significant predation on fish. The common dab [Limanda limanda (L.)] took a wider range of prey species than the plaice, but also depended mainly on polychaetes, crustaceans and bivalves. Depth distribution may limit both intra- and interspecific competition between these fish and also influence the choice of prey. The results from the main nursery areas of Irvine and Ayr Bays were similar to those from the other bays throughout the Clyde Sea Area and support earlier work at Firemore Bay in north-west Scotland and in the Dutch Wadden Sea.The growth rate of the fish increases during the early summer and may be related to increasing food availability, feeding experience of the fish and longer day length. Growth rate between areas appeared to be correlated with benthic productivity. 0-group plaice in Irvine, Ayr and Firemore Bays grew to different mean lengths by the end of the summer growth season, being 82 mm, 73 mm and 61 mm, respectively, for the period 1972–1974. This agrees with the known differences in standing stocks of intertidal macrobenthos in these bays (17·0, 11·1 and 1·3 g m?2 dry weight, respectively). The significance of this in relation to survival is discussed. Offshore migration of the larger fish in the autumn may result in apparent slowing of growth rates prematurely in inshore areas. The year-class strength depends more on the food availability in the nursery areas than on the number of plaice that settle on the bottom. 相似文献
16.
《Marine environmental research》1987,21(1):49-58
Pink salmon, Oncorhynchus gorbuscha, alevins (5 and 60 days after hatching) were continuously or intermittently exposed for 30 days to the water-soluble fraction (WSF) of Cook Inlet crude oil in fresh water or in a simulated freshwater-seawater cycle. Alevins exposed to 0·7−2·4 mg/liter WSF in the simulated tidal cycle were more sensitive to oil, had reduced yolk reserves, and accumulated more hydrocarbons than did alevins exposed to the same concentrations in fresh water. Alevins in fresh water were more sensitive to continuous than to intermittent exposures. In all exposures, 60-day alevins were more severely affected than were 5-day alevins. 相似文献
17.
Behavioural responses to chlorinated seawater were studied in the laboratory using eight species of fish (topsmelt, Atherinops affinis [Ayres]; pile perch, Rhacochilus vacca [Girard]; señorita, Oxyjulis californica [Günther]; blacksmith, Chromis punctipinnis [Cooper]; northern anchovy, Engraulis mordax [Girard]; opaleye, Girella nigricans [Ayres]; bluebanded goby, Lythrypnus dalli [Gilbert] and mussel blenny, Hypsoblennius jenkinsi Jordan and Evermann) which occur near the Units 7 and 8 discharge of Southern California Edison's Redondo Beach Steam Generating Plant in King Harbor, California, USA. All species except Engraulis demonstrated prolonged avoidance of chlorinated quadrants of the behaviour chamber. The avoidance thresholds were species-specific and species totally avoided estimated total residual oxidant (TRO) concentrations from 0·094 to 0·456 mg/litre. Calculated significant avoidance thresholds averaged 0·066 mg/litre TRO; young Atherinops significantly avoided TRO concentrations as low as 0·028 mg/litre (p < 0·001). The highest avoidance thresholds were exhibited by sedentary species and were modified by the presence of cover inside the behaviour chamber. The avoidance response protected against mortality in all species except Lythrypnus and Engraulis. 相似文献
18.
Gamak Bay is one of the largest aquaculture areas in the South Sea of Korea and exhibits hypoxia conditions during the summer. The harmful effects of hypoxia on aquaculture fish stock have not been elucidated. This study describes the biochemical effects of low levels of dissolved oxygen (DO) on cultivated juvenile Sebastes schlegeli in Gamak Bay. The hypoxia-inducible factor 1α (HIF1α) gene was induced significantly in S. schlegeli collected from low oxygen level areas, which suggests that fluctuations in the DO induces the expression of HIF1α. The level of antioxidant enzyme exhibited significantly higher activities in fish obtained from station F2 in which low levels of DO were shown in 2010 and 2011. The results of this study demonstrate that cultivated S. schlegeli are affected by the low levels of DO in Gamak Bay and superoxide dismutase enzymes operate dependently with HIF1α. The plasma glucose level did not exhibit significant difference in the fish among the sampling stations. We noted that HIF1α and the superoxide dismutase enzymes are useful biomarkers that might enable the detection of otherwise unnoticed hypoxic stress. 相似文献
19.
《Marine environmental research》1987,23(1):49-64
The bivalves Protothaca staminea and Mytilus edulis were exposed to five depths of decomposing bark from an active log transfer facility for 13–96 days in a field experiment at Auke Bay, Alaska. Survival and condition of both species was inversely related to depth and duration of bark coverage. As little as 6 cm of bark reduced survival; survival declined most rapidly between 10 and 15 cm of bark. The depths of bark under which half the animals died after 96 days of exposure were 12·8 ± 1·6 cm for P. staminea and 10·9 ± 1·5 cm for M. edulis. Interstitial water in the bark deposits had low concentrations of dissolved O2 (2·5–5·3 mg/liter) and elevated concentrations of hydrogen sulfide (1·0–8·1 mg/liter total sulfide) and ammonia (46–131 μg-at N/liter) compared to the surface water from the control treatment. Survival of P. staminea and M. edulis was inversely related to concentrations of hydrogen sulfide and ammonia and directly related to dissolved O2 concentrations. 相似文献
20.
Bruce E. Frey G.Fritz Riedel Ann E. Bass Lawrence F. Small 《Estuarine, Coastal and Shelf Science》1983,17(2):181-187
Experiments were conducted in which we tested the effects of hexavalent chromium on both natural assemblages of phytoplankton and cultures of Thalassiosira pseudonana clone 3H. Water was collected from various locations in Yaquina Bay, Oregon, with salinities ranging from 32·5‰ to 0·03‰. A variety of nutrient regimes were tested by adding major nutrients and micro-nutrients, and/or stripping micro-nutrients with activated carbon. In one high salinity experiment, chromium was stimulatory, as were micro-nutrient additions. In other high and medium salinity experiments, chromium was neither stimulatory nor inhibitory, at levels up to 1·9 μ mole l?1 Cr. There was, however, slight inhibition of growth at 19·0 μ mole l?1 Cr, due specifically to inhibition of Skeletonema costatum. In our freshwater experiments, chromium was very inhibitory at 1·9 μ mole l?1 Cr, and slightly inhibitory at 0·19 μ mole l?1 Cr. Species inhibited by chromium were Surirella ovata, Detonula confervacea, and Cyclotella sp. Experiments were conducted with T. pseudonana grown over a wide range of salinities. Chromium was found to be very inhibitory in freshwater and became progressively less toxic as the salinity increased. Most inhibition was neutralized by a salinity of 2·1‰. 相似文献