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1.
Four coastal ecosystems with contrasting characteristics were sampled in Costa Rica (2000-2002). Oil pollution status, expressed as the fraction of dissolved/dispersed petroleum hydrocarbons related to chrysene equivalents, was determined by the molecular fluorescence analytical technique. A total of 130 water samples were taken, from the Caribbean (Moín Bay), and from the Pacific (Bahía Culebra, Gulf of Nicoya and Dulce Gulf). On one occasion, seven samples along the Puntarenas estuary were also analysed. In Moín the mean and standard deviation were 0.10 microg x L(-1) +/- 0.18 micro x L(-1), ranging from non detectable (nd) to 0.65 microg x L(-1). For the Pacific ecosystems the total range was from nd to 0.37 microg x L(-1). In Bahia Culebra no fluorescence signals were obtained. In the Gulf of Nicoya the mean and standard deviation were 0.04 microg x L(-1) +/- 0.09 microg x L(-1), from nd to 0.33 microg x L(-1). Values in Dulce Gulf were 0.05 microg x L(-1) +/- 0.11 microg x L(-1), from nd to 0.37 microg x L(-1). Along the Puntarenas estuary the range was 0.17 to 5.91 microg x L(-1), with a mean of 1.21 microg x L(-1) and a standard deviation of +/- 2.10 microg x L(-1). The four coastal ecosystems had concentrations below the 10 microg x L(-1) limit for polluted oceanic areas. The Puntarenas estuary reflects the influence of antropogenic activities from and around the City of Puntarenas. These levels are considered low for inshore waters.  相似文献   

2.
This paper describes the initial investigation of PCB concentrations in four geographical regions (three on the Pacific and one in the Caribbean) of coastal Costa Rica: Bahia Culebra, Golfo Dulce, Golfo de Nicoya, and Limón. Overall total concentrations of PCB were low in all areas except around the port of Golfito (Golfo Dulce). Overall average concentration is 2.80 ng/g dw, with a standard deviation of 2.75. The low concentration could be due to lack of contamination or the subsequent degradation in the warm climate, or the low sorptive capacity of the sediment. Further investigation is ongoing.  相似文献   

3.
Few papers concerning seagrasses of the eastern Pacific have been published. This paper presents the first ecological data on the seagrass, Ruppia maritima, from a non-lagoonal setting in the eastern Pacific. A 5000 m2 patch formed by R. maritima, at Playa Iguanita, Bahía Culebra, Pacific coast of Costa Rica was studied. Plant density and leaf length of R. maritima were determined along two transects on different dates. Above and below ground biomass were calculated along one transect. Plant density ranged from 1590 to 8630 individuals m(-2) along the two transects, with means of 5990 +/- 1636 and 6100 +/- 1876 plants m(-2) for transect 1 and 2, respectively. Longest leaf length per plant varied between 0.5 and 23.0 cm. Leaf biomass (LB) ranged from 10 to 97 gm(-2), and root-rhizome biomass (RB) from 31 to 411 gm(-2), resulting in RB:LB ratios of 3.07 to 15.27. Total biomass at Bahía Culebra was lower than at tropical lagoons on the Pacific coast of Mexico, but higher than in the Gulf of Mexico. The below ground: above ground biomass ratio was much higher at Bahía Culebra than at other sites on the Pacific coast of Mexico and the Gulf of Mexico. Another seagrass present at Bahía Culebra was Halophila baillonii, with low densities on the deepest section of the patch. At least 44 invertebrate species associated with the seagrass bed have also been identified. The patch at Playa Iguanita and other sites within Bahía Culebra, as well as their associated organisms, disappeared after a severe storm in June 1996. No seagrasses have been found in the area or in any other location on the Pacific coast of Costa Rica since then.  相似文献   

4.
The studies on marine copepods of Costa Rica started in the 1990’s and focused on the largest coastal-estuarine systems in the country, particularly along the Pacific coast. Diversity is widely variable among these systems: 40 species have been recorded in the Culebra Bay influenced by upwelling, northern Pacific coast, only 12 in the Gulf of Nicoya estuarine system, and 38 in Golfo Dulce, an anoxic basin in the southern Pacific coast of the country. Freshwater environments of Costa Rica are known to harbor a moderate diversity of continental copepods (25 species), which includes 6 calanoids, 17 cyclopoids and only two harpacticoids. Of the +100 freshwater species recorded in Central America, six are known only from Costa Rica, and one appears to be endemic to this country. The freshwater copepod fauna of Costa Rica is clearly the best known in Central America. Overall, six of the 10 orders of Copepoda are reported from Costa Rica. A previous summary by 2001 of the free-living copepod diversity in the country included 80 marine species (67 pelagic, 13 benthic). By 2009, the number of marine species increased to 209: 164 from the Pacific (49% of the copepod fauna from the Eastern Tropical Pacific) and 45 from the Caribbean coast (8% of species known from the Caribbean Basin). Both the Caribbean and Pacific species lists are growing. Additional collections of copepods at Cocos Island, an oceanic island 530 km away of the Pacific coast, have revealed many new records, including five new marine species from Costa Rica. Currently, the known diversity of marine copepods of Costa Rica is still in development and represents up to 52.6% of the total marine microcrustaceans recorded in the country. Future sampling and taxonomic efforts in the marine habitats should emphasize oceanic environments including deep waters but also littoral communities. Several Costa Rican records of freshwater copepods are likely to represent undescribed species. Also, the biogeographic relevance of the inland copepod fauna of Costa Rica requires more detailed surveys.  相似文献   

5.
The proximity of coral reefs to areas of present and future coastal development in Costa Rica highlights the need for assessing environmental conditions important to maintaining healthy corals. In January 1997 a survey of light penetration, inorganic nutrient concentrations, temperature, and salinity was conducted in the patch reefs of Bahía Culebra (Pacific Ocean) and on the Caribbean coast in the fringing reef at Parque Nacional Cahuita and near Limón. Temperature was 28 degrees C at all sites, and salinity ranged from 33 to 36 psu. Light attenuation coefficients ranged from 0.12 to 0.29 m(-1) in reef areas. Seawater nutrient concentrations were within the range of concentrations reported for tropical reef waters; combined NO3- and NO2- and PO4(3-) were each below 1 microM. NH4+ ranged from 0.2 to 7 microM, representing a significant source of nitrogen. The ratio of total dissolved inorganic nitrogen to phosphate averaged 27 for all reef waters. The high nitrate (3.6 microM) and light attenuation (0.95 m(-1)) values from the surface waters of the La Estrella plume (Caribbean coast) show that this river represents a significant source of nitrogen and light attenuation for the neighboring reefs at Cahuita. This survey provides a useful baseline for future studies, which should monitor these important coastal coral reef areas during both wet and dry seasons.  相似文献   

6.
Parallel to a zooplankton study (1999-2000) observations were made (from an inflatable boat), on the presence of dolphins along a transect (-8 km long) on the axis of Culebra Bay (24 km2), Gulf of Papagayo, Pacific coast of Costa Rica. Dolphins were found during 20 of the 31 boat surveys conducted. The only species of cetacean found in the bay was Stenella attenuata, the spotted dolphin. These sightings were more frequent during the rainy season, particularly during the month of May of both years. The presence of S. attenuata in Culebra Bay might be associated to the abundances of fish and mollusks (their presumed prey: for example, squids), as evidenced by fishery statistics available for this zone of the Pacific coast of Costa Rica.  相似文献   

7.
Thirty-one sediment samples collected from 1996-2003 from the Gulf of Nicoya estuary on the northwestern coast of Costa Rica, have been obtained for PCB analyses. This is part of the first study to evaluate the PCB contamination in coastal Costa Rica. Overall, the concentrations are low, especially when compared to sediments from more temperate climates and/or sediments from more heavily industrialized areas. Values average less than 3 ng/g dw sediment, however, a few samples contained up to 7 ng/g dw sediment. Sediments with the highest concentrations were located in the Punta Morales area, where muds were sampled from among mangrove roots. The Puntarenas samples had surprisingly low PCB concentrations, likely due to their sandy lithology. The congener distribution within the majority of the samples showed signs of either recent sources or lack of degradation. However, a few sites, specifically some of the inter-gulf islands and more remote samples had congener distributions indicative of airborne contaminants and/or degradation. Considering the presence of airborne PCBs in the Gulf of Papagayo to the north, the lack of airborne PCBs and more varied congener distribution in the Gulf of Nicoya estuary was surprising.  相似文献   

8.
The Gulf of Paria receives heavy metal input from urban runoff, industrial and agricultural activity, sewage and domestic wastes: both from the west coast and from inland areas of Trinidad. Non-residual concentrations of nine metals, as well as total mercury concentrations, were used to determine spatial distributions of heavy metals in sediments in the Gulf of Paria. Surficial sediment samples were collected at 37 stations, which included the mouths of 11 major rivers that flow into the Gulf of Paria. Stations were sampled twice during the wet season (July 1998 and November/ December 1998) and twice during the dry season (March 1999 and April 1999). Sediments were analyzed for aluminium (Al), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni), zinc (Zn) and mercury (Hg). Total Organic Carbon (TOC) and grain size analyses were also performed on the sediments. Principal component analysis showed that sediments from river mouths subject to greatest land use and anthropogenic input, were distinct from other sediments in the Gulf of Paria. This was due to higher Pb, Zn, Cu and Hg concentrations (3.53-73.30 microg g(-1), 45.8-313.9 microg g(-1), 8.43-39.71 microg g(-1) and 0.03-0.10 microg g(-1), respectively). Sediments further from the coast were also distinct due to their higher Al, Fe, Cr and Mn concentrations (1.37-3.16 mg g(-1), 9.51-18.91 mg g(-1) , 17.22-28.41 microg g(-1) and 323.6-1,564.2 microg g(-1), respectively). Cd and Pb were higher in the wet season while Ni was higher in the dry season. Pb, Zn, Cu and Hg were correlated with each other and with TOC. Correlation was also observed between Al, Fe, Cr, Mn and Ni. Al, Fe, Cr and Mn were correlated with percentage clay in sediments. The results suggest that Pb, Zn, Cu and Hg are preferentially removed by organic matter, which settles at the river-mouths, while Al, Fe, Cr, Mn, and Ni become associated with clay minerals and are transported away from the coast.  相似文献   

9.
Twenty-nine marine sediment samples collected from 1996 through 2002 from the Golfo Dulce embayment of Costa Rica were analyzed for PCB concentrations. The Esquinas River and Rincon Bay in the northern and western part of the gulf had relatively low overall concentrations of PCBs, with no samples having greater than 2.1 microg/g dw sediment. The Port of Golfito had the highest overall concentrations, ranging up to 15.7 microg/g dw sediment. These samples were also dominated by higher chlorinated congeners. Samples from the deeper (> 100 m) waters in the northern part of the gulf, as well as within the sediment plume from the Rio Coto Colorado had intermediate values. Within the Rio Coto Colorado sediment plume the concentrations did decrease with increasing depth and the congeners showed a shift towards less chlorinated congeners with depth. However, the deep northern basin had some of the highest PCB concentrations and the shift towards less chlorinated congeners was not apparent or significant. Whether the anoxic conditions that exist in the deep waters are capable of initiating dechlorination is still unknown. Overall, the data from Golfo Dulce show moderate PCB contamination, despite the pristine nature of the gulf and surrounding lands.  相似文献   

10.
The variability of Fe, Mn, Zn, Cu, Pb, Cd, and Ni concentrations was studied in soft tissues of the common mytilid mollusk Septifer bilocularis collected in May 2013 at the coral reefs along the entire Vietnamese coast from the Gulf of Siam to Ha Long Bay. The salinity, suspended solids, and nutrients were determined during the sampling; these hydrochemical characteristics of the surrounding waters were controlled by the river runoff and the content of chlorophyll a. The concentration of Mn in the mollusk S. bilocularis was elevated under the river runoff effect. However, concentrations of Cd and Zn in S. bilocularis were the lowest within the areas of river influence and increased in waters of central Vietnam and the Gulf of Siam, where upwellings are an important driving force. A comparison of our data with those obtained for Mytilidae from other regions showed that the mussel S. bilocularis can be recommended for biomonitoring of the concentrations of trace metals in the waters of coral ecosystems along the Vietnam coast.  相似文献   

11.
12.
The Gulf of Paria is bordered by both Trinidad and Venezuela, from which various metallic pollutants and other contaminants can originate. The Gulf is still a significant source of fish, crabs and shellfish for human consumption to both countries, where concerns over the quality of this marine environment have been long expressed but never properly addressed. In addition, the circulatory current patterns in the Gulf ensure that contaminants originating from either country are likely to affect both countries eventually. Heavy metals were determined in oysters (Crassostrea rhizophorae and C. virginica), green mussels (Perna viridis) and sediments from the Gulf of Paria. Samples were obtained at four sites in Trinidad and three sites in Venezuela in the Gulf of Paria, in addition to comparative samples collected from three sites on the north coast of Venezuela. Edible tissues of twelve shellfish from each location were blended and aliquots digested with concentrated nitric acid, for extraction of cadmium, chromium, copper, lead, nickel and zinc. The solutions were analysed by flame atomic absorption spectroscopy. Mercury was extracted with a mixture of nitric, hydrochloric and sulphuric acids and determined by cold vapour atomic absorption. Sediments were oven-dried at 60'C, before being similarly extracted. Results showed that mercury in sediments at all sites in Trinidad and Venezuela exceeded NOAA and Canadian sediment quality guidelines, while cadmium, copper, nickel, lead and zinc also exceeded these guidelines at several sites. Heavy metal levels in oysters and green mussels varied widely with location. However, oysters from the Gulf of Paria contained significantly higher mean levels of cadmium, copper, nickel and zinc than those from the north coast of Venezuela, but this difference was not apparent in mussels. Cadmium, mercury and zinc in sediments were significantly correlated with those of mussels, but not of oysters, in which copper and zinc at several sites in the Gulf of Paria exceeded local maximum permissible levels (Cu = 20 microg g(-1) wet wt; Zn = 50 microg g(-1) wet wt) for human consumption. These findings indicate that while mussels may be better biological indicators of heavy metal pollution in sediments than oysters, the latter may provide copper and zinc contamination. Further research is needed to determine the most appropriate biological indicators of heavy metal and other pollutants in the local marine environment and to develop protocols for their use.  相似文献   

13.
Among the many ecosystem services provided by mangrove ecosystems, their role in carbon (C) sequestration and storage is quite high compared to other tropical forests. Mangrove forests occupy less than 1 % of tropical forested areas but account for approximately 3 % of global carbon sequestration by tropical forests. Yet there remain many areas where little data on the size and variation of mangrove C stocks exist. To address this gap and examine the range of C stocks in mangroves at landscape scales, we quantified C stocks of Honduran mangroves along the Pacific and Caribbean coasts and the Bay Islands. We also examined differences in ecosystem C stocks due to size and structure of mangrove vegetation found in Honduras. Ecosystem C stocks ranged from 570 Mg C ha?1 in the Pacific coast to ~1000 Mg C ha?1 in Caribbean coast and the Bay Islands. Ecosystem C stocks on the basis of mangrove structure were 1200, 800 and 900 Mg C ha?1, in low, medium and tall mangroves, respectively. We did not find significant differences in ecosystem C stocks on the basis of location (Pacific coast, Caribbean coast and Bay Islands) or mangrove type (low, medium and tall). Mangrove soils represented the single largest pool of total C in these ecosystems, with 87, 81 and 94 % at the Pacific coast, Caribbean coast and the Bay Islands, respectively. While there were no significant differences in total ecosystem stocks among mangrove types, there were differences in where carbon is stored. Mangrove soils among low, medium and tall mangroves contained 99, 93 and 80 % of the total ecosystem C stocks. In addition, we found a small yet significant negative correlation between vegetation C pools and pore water salinity and pH at the sampled sites. Conversion of mangroves into other land use types such as aquaculture or agriculture could result in loses of these soil C reserves due to mineralization and oxidation. Coupled with their other ecosystem services, an understanding of the size of mangrove ecosystem C stocks underscores their values in the formulation of conservation and climate change mitigation strategies in Central America.  相似文献   

14.
Superficial seawater temperature (SST) and at two depths (7 and 12 m) were measured non-continuously during the study of the corals and coral reefs of Culebra Bay (1993-1996). SST showed seasonal variations of approximately 4 degrees C. The highest average temperatures (27.0 +/- 0.1, range 23-29 degrees C) were during the rainy season from May to November and the lowest (22.9 +/- 0.3 degrees C, 15.5-29 degrees C) during the dry season from December to April. Cold fronts with 2-3 degrees C differences in SST frequently pass into the bay and remain there for several hours according to the tidal cycles. Differences of approximately 3 degrees C between SST and the bottom (5-10 m depth) were usually found, particularly at locations where bottom topography and tidal circulation produced tidal bores. The average temperatures recorded by data loggers placed at 7 and 12 m depth on a coral reef at the outer shores of Culebra Bay, were 27.1 +/- 0.02 degrees C (20.5-31.6 degrees C) and 25.8 +/- 0.04 (9.9-31.5 degrees C) respectively. The seasonal pattern of higher and lower temperatures corresponds respectively to the rainy and dry season of the northern Pacific coast of Costa Rica. Water temperature at 12 m was < 14 degrees C for some hours during an upwelling event whilst minimum temperatures at 7 m were > or = 22 degrees C. Negative temperature anomalies coincided with an increase of the NE-E winds intensity and there is a lunar and tidal component which influence diumal variations of temperature. These results suggest that coral reefs built by branching species (e.g. Pocillopora spp.) in Culebra Bay could be limited by both the influence of cold fronts and by seasonal upwellings which affect negatively those coral species, as reported for other locations in the tropical eastern Pacific.  相似文献   

15.
The concentrations of copper, molybdenum and zinc were measured in the liver of normal grazing sheep and lambs from Eastern Norway, and in sheep dead of chronic copper poisoning. The following mean values were found: Normal sheep: 173 ± 130 μg Gu/g wet weight, 1.0 ±0.3 μg Mo/g, and 49 ± 10 μg Zn/g; lambs: 129 ± 59 μg Gu/g, 0.9 ± 0.3 μg Mo/g, and 46 ±9 μg Zn/g; sheep dead of copper poisoning: 429 ± 249 μg Gu/g, 0.4 ± 0.1 μg Mo/g, and 43 ± 2d μg Zn/g. Sheep with low liver copper (Gu < 10 μg/g) were also analyzed for molybdenum and zinc, with the following results: 1.0 ± 0.2 μg Mo/g, and 45 ± 8 μg Zn/g wet weight. The differences in liver copper between all the groups, and the differences in molybdenum concentrations between the normal sheep and the lambs and between the normal sheep and the poisoned sheep were significant (P < 0.001). No significant correlations between liver copper/liver molybdenum or liver copper/liver zinc were detected.  相似文献   

16.
Six weak whooper swans (Cygnus cygnus) and two weak tundra swans (Cygnus columbianus) were found at Swamp Miyajima (Hokkaido, Japan) in May 1998. Anorexia, depression, green watery feces, pale conjunctiva, and anemia were observed. Radiographs showed from six to 38 suspected lead pellets in the gizzard. Blood lead concentrations were 2.5-6.7 microg/g (mean+/-SD=4.6+/-1.14 microg/g) on day 1. After blood collection, the birds were treated with calcium disodium ethylenediaminetetraacetate (CaEDTA) given intravenously and force fed. Despite treatment, seven birds died the next day. Green, bile-stained livers and pale or green kidneys were observed on necropsy. Microscopically, bile pigment was widespread in the liver and acid-fast intranuclear inclusion bodies were observed in renal tubular epithelium. Lead concentrations in livers and kidneys were 14.0-30.4 microg/g and 30.2-122 microg/g wet weight, respectively. Only one bird survived and this whooper swan continued to be treated with CaEDTA and activated charcoal. No lead shot was observed in the proventriculus and gizzard by radiography on day 64 and the blood lead concentration decreased from 2.9 microg/g to 0.09 microg/g during that same period. After 4 mo of rehabilitation, the whooper swan was returned to the wild. Lead intoxication continues to be a problem at Swamp Miyajima.  相似文献   

17.
A severe outbreak of Paralytic Shellfish Poisoning (PSP) occurred in Manzanillo and Guayacán, northwestern coast of Margarita Island, Venezuela, between August and October 1991. A bloom of dinoflagellates including Prorocentrum gracile, Gymnodinium catenatum and Alexandrium tamarense seemed to be responsible for this outbreak. Levels of PSP toxins in mussels (Perna perna) exceeded the international safety limit of saxitoxin, 80 microg STX/100 microg meat. PSP toxin values varied between 2548 and 115 microg STX/100 g meat in Manzanillo, and between 1422 and 86 microg STX/100 g meat in Guayacán. At both locations, the highest levels were detected in August, when 24 patients exhibited typical symptoms of PSP toxicity after consuming cooked mussels (16 required hospitalization). A high pressure liquid chromatographic (HPLC) procedure was recently used on the 1991 samples. The major toxin detected in samples of both locations was decarbamoyl saxitoxin (dcSTX), but low concentrations of saxitoxin were also found in Manzanillo samples. Gonyautoxins GTX1, GTX2 and GTX3 were detected only at Guayacán, while in both locations, decarbamoylgonyatouxin (dcGTX2,3) toxins were detected. These findings represent the first time that causative toxins of PSP in Venezuela have been chemically identified, and confirm the presence of dcSTX and dcGTX in mussels from the Caribbean Sea. The presence of dcSTX and dcGTX in shellfish is indicative that Gymnodinium catenatum was a causative organism for outbreak of PSP.  相似文献   

18.
This is the first record of the dinoflagellate Lingulodinium polyedrum in a red tide bloom in the North Pacific coast of Costa Rica. The sample was collected on April 2000 at Culebra Bay, Gulf of Papagayo, from a patch of aproximatly 2000 m2, which produced a red discoloration of the water and a peculiar strong odor. This species produces spherical hypnocysts that may remain for decades when dark or anoxic conditions are present; L. polyedrum had been associated with the production of paralyzing toxins such as saxitoxins and yessotoxins. A second smaller patch was observed close Panama beach, into the bay, where we found seven puffer fish (Diodontidae) and two lobsters dead in the sand. It is important to develop a monitoring program to identify seasonal behavior of this species and ameliorate its impact on coastal human communities.  相似文献   

19.
This report is part of a series that summarizes the species and localities of Costa Rican marine taxa. A review of the literature on copepods, both pelagic and benthic for the Pacific and Caribbean coast of Costa Rica, includes eighty species. Sixty seven pelagic species have been found, distributed between sixteen calanoid, one cyclopoid, three harparticoid and four poecilostomatoid families. Moreover, thirteen benthonic species distributed into six families, all harparticoids, are reported. Among the pelagic families, Pontellidae has six species, while Paracalanidae and Eucalanidae had five each. Other families, like Calanidae, Pseudodiaptomidae and Acartiidae had four species and most families only one. Forty five species are reported only for the Pacific coast, thirteen for the Caribbean coast, only nine species occurred in both coasts; being a direct consequence of the more intensive research effort in the Pacific. Pelagic copepod biodiversity reflects different oceanographic conditions in both coasts. Typical estuarine species were found in the lower region of the Gulf of Nicoya, while a mixture of estuarine and oceanic species were found in Golfo Dulce. Diversity in the Caribbean, specially at the Cahuita coral reef is lower in comparison with the copepod diversity found in other regions in the Caribbean sea. This may be due to the high sediment resuspension rate characteristic of the Cahuita coral reef, which could affect the reproduction of many holozooplankters, specially copepods. Although sixty seven pelagic copepod species appears to be in low numbers, in terms of specific biodiversity it is as high when compared to numbers found in other tropical areas. Thirteen species are reported in the literature, all harparticoids. Five species, three sub-species and one genera were new to science. Balacopsylla is reported for the first time from a neotropical regions, while the genus Karllangia, represented by two coexisting species in the Caribbean coast, belong to a few circumtropical-subtropical genera. The most diverse family was Tetragonicipitidae. This is the first effort to summarize the available information about the biodiversity of marine copepods for Costa Rica's coasts.  相似文献   

20.
Gymnodinium bloom events are of concern, since they produce toxins, which have unfavorable consequences to marine ecosystems, human health and the economy. This report describes the physico-chemical conditions that were present during the algal bloom event on May 2010 in Bahía Manzanillo and Bahía Santiago, Colima, Mexico. For this, seawater nutrient analysis, phytoplankton counts, identification, and toxicity tests were undertaken. Nutrients in seawater were determined using colorimetric techniques, the higher concentrations (8.88 microM DIN, 0.78 microM PO4 and 24.34 microM SiO2) were related with upwelling waters that promoted the algal bloom that began after registering the year lowest sea-surface temperature, favoring the rapid growth of G. catenatum (up to 1.02 x 10(7) cells/L). Phytoplankton counting was carried out using sedimentation chambers and cells enumerated on appropriated area. The bloom persisted in the bays for approximately two weeks and was associated with toxicity (determined with HPLC) in local oysters (1525.8 microg STXeq/100g), and in phytoplankton (10.9 pg STXeq/cells) samples. Strong variations in cell toxicity (1.4 to 10.9pg STXeq/cells), most likely reflected the availability of inorganic nutrients. The toxin profile of the phytoplankton samples consisted of 11 toxins and resembled those recorded for several strains of G. catenatum isolated from other coastal areas of Mexico.  相似文献   

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