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1.
Jakarta is a booming coastal megacity in Indonesia with over 10 million inhabitants. The rivers flowing through the city district receive enormous amounts of untreated wastewaters from households and industries and discharge high pollutant loads into Jakarta Bay. Applying a screening approach for the identification of characteristic site-specific and harmful organic contaminants, we frequently found the insect repellent N,N-diethyl-m-toluamide (DEET) in river water and seawater samples from Jakarta. The compound was previously reported as persistent aquatic contaminant in industrial countries, and we present here the first data set from a tropical megacity. Concentrations in river water and seawater from Jakarta were exceptionally high, up to 24,000 ng L?1, and exceeded by far all published concentrations in surface waters worldwide. We explained this with massive usage of the compound, lack of wastewater treatment and low average river flow as compared to rivers in other tropical megacities. The usage and properties of DEET indicate its suitability as molecular marker of municipal wastewaters. Such markers are useful to trace emissions from specific pollution sources in aquatic systems as a basis for the investigation of related impacts. We show here that DEET is in particular useful to trace the long-range distribution of municipal wastewaters in tropical freshwater and coastal systems. This application is of great value for tracing such inputs in tropical coastal habitats which are sensitive to changing water quality like coral reefs. This assists to uncover whether specific conditions in these systems could be related to pollutant inputs from land.  相似文献   

2.
Spatial variation in the epilithic algal matrix (EAM) cryptofauna was investigated at three locations on the Great Barrier Reef: two inner shelf—Orpheus Island and the Turtle Island group—and a mid-shelf location, Lizard Island. Although the EAM appears to be a relatively simple and consistent habitat, significant differences in cryptofaunal assemblages were found between locations. EAM assemblages from Orpheus Island were markedly different. This appears to be a function of the sediment profile characteristics (grain size >60 µm) at Orpheus Island, as many cryptofaunal taxa displayed positive relationships with sediment volume. However, sediment volumes did not differ significantly between the three locations, highlighting the possibility of cyclonic activity affecting the sediment profile at Orpheus Island in the months preceding the study, in addition to the nutrient input from major terrigenous sources. The results of this study show that EAM cryptofaunal assemblages are not uniform across the Great Barrier Reef and suggest that dissolved nutrients, sediment loads and distance from river systems may be significant drivers of cryptobenthic faunal compositions.  相似文献   

3.
Lipid class profiles and total fatty acid composition of particulate matter were studied in the northeast Atlantic during the spring bloom and fall. Eddies of known physical and chemical properties were sampled at different depths. HPLC pigment data were used to characterize the phytoplankton communities. In spring, a dominance of prymnesiophytes was recorded at all depths, while in fall prochlorophytes dominated near the surface and prymnesiophytes only at deep chlorophyll maximum. Lipid classes included triglycerides, sterols, glycolipids and phospholipids. A differential relationship between phytoplankton abundance and lipid accumulation was observed: spring lipid concentrations were positively related to phytoplankton biomass, while fall particulate lipid did not show any relationship. The main feature was a northward increase in lipid concentrations unrelated to the mesoscale hydrological structures. Polar lipids dominated over neutral acyl-glycerols with phospholipids dominating over glycolipids in spring, while glycolipids dominated in fall. This resulted from different nutrient availability with a dominance of flagellates associated with mesotrophy in spring and of picophytoplankton associated with oligotrophy in fall. In terms of fatty acids, factorial correspondence analyses illustrate the influence of seasonally changing assemblages: (1) in spring, the main source of variability was the bloom with an opposition between bloom sites characterized by n-3 and n-6 PUFA, and more detrital deep samples characterized by saturated, monoenoic and branched acids; (2) fall fatty acid profiles were similar at all depths and very close to those observed for spring deep samples. Comparison of pigment and fatty acids using redundancy analysis suggested that pelagophytes were linked to saturated and branched acids. It also showed that prymnesiophytes and prochlorophytes were significantly associated with n-6 and n-3 PUFA. The spring period illustrated the complexity of these relationships with dinoflagellates and prymnesiophytes linked with n-3 PUFA, diatoms linked with palmitoleic and myristic acids, and pelagophytes linked with n-6 PUFA and higher-chain-length monoenes.  相似文献   

4.
P. Dustan 《Marine Biology》1975,33(2):101-107
The in-situ growth rate of the reef coral Montastrea annularis on a reef at Jamaica, W. Indies was determined for a 1-year period using Alizarin Red-S staining techniques. Growth rate is correlated with water depth and growth form. The flattened growth form of M. annularis allows for continued rapid increase in colony surface area at low light intensities. The geomorphology of Jamaican reefs may in part be controlled by the population ecology of M. annularis.  相似文献   

5.
Habitat destruction leading to increased fragmentation is detrimental to species by reducing population size and genetic diversity and by restraining population connectivity. However, little is known about the effects of naturally fragmented habitats on wild populations, especially when it comes to marine benthic invertebrates with long pelagic larval duration. In this framework, we investigated the connectivity and genetic diversity variation among nine wild populations of the black-lipped pearl oyster, Pinctada margaritifera, throughout French Polynesia using ten microsatellite DNA markers. Despite the naturally fragmented habitat (South Pacific oceanic islands), we found high values of genetic diversity and population admixture, indicating connectivity at small and large spatial scales within sampled sites of the Tuamotu, and between the Society and Tuamotu Archipelagos. In the meantime, habitat geomorphology increased genetic drift in populations occurring in small, closed lagoons. Significant genetic structure not correlated to geographic distance was detected mainly between closed and open lagoons. The Marquesas Islands hosted the most divergent populations, likely a result of vicariance. Our results also highlight that migration patterns among lagoons are not symmetrical. Altogether, the general pattern of gene flow, nonsymmetrical migration rates among populations, absence of isolation by distance and absence of recent extinction events found in our study strongly suggest that P. margaritifera populations of French Polynesia follow an asymmetrical island model of dispersal.  相似文献   

6.
Abnormal processes of calcification, such as regenerating lesions and neoplasia, situated near the tips(<25 cm) of colonies of Acropora palmata (Lamarck) suppressed normal linear growth. Branches having neoplasia at a larger distance from the tip do not grow significantly differently from controls. This indicates a functional minimal area in terms of energy supply. Neoplasia are pure aragonite and have the same coenosteal structure as regenerative skeletal material. Regeneration of tissue as well as tissue+skeleton lesions involves the simultaneous formation of tissue and regenerative skeleton, trapping foreign material under the regenerated surface. Recovery of a damaged surface slows down with time and this may, in other coral species, result in permanent lesions. A. palmata recovered from all lesions (n=32) within 80 d and appears to be a superior regenerator among Caribbean corals. This is consistent with other life-history characteristics of this highly specialized coral species.  相似文献   

7.
8.
Hierarchical modeling of abundance in space or time using closed-population mark-recapture under heterogeneity (model \(\hbox {M}_{\text {h}}\) ) presents two challenges: (i) finding a flexible likelihood in which abundance appears as an explicit parameter and (ii) fitting the hierarchical model for abundance. The first challenge arises because abundance not only indexes the population size, it also determines the dimension of the capture probabilities in heterogeneity models. A common approach is to use data augmentation to include these capture probabilities directly into the likelihood and fit the model using Bayesian inference via Markov chain Monte Carlo (MCMC). Two such examples of this approach are (i) explicit trans-dimensional MCMC, and (ii) superpopulation data augmentation. The superpopulation approach has the advantage of simple specification that is easily implemented in BUGS and related software. However, it reparameterizes the model so that abundance is no longer included, except as a derived quantity. This is a drawback when hierarchical models for abundance, or related parameters, are desired. Here, we analytically compare the two approaches and show that they are more closely related than might appear superficially. We exploit this relationship to specify the model in a way that allows us to include abundance as a parameter and that facilitates hierarchical modeling using readily available software such as BUGS. We use this approach to model trends in grizzly bear abundance in Yellowstone National Park from 1986 to 1998.  相似文献   

9.
Phosphorus (P) is both a nutrient and a pollutant. For instance, excess P induces water eutrophication followed by death of fishes and other water life. Determination of organic P content in sediments is therefore important to study P cycling and environmental pollution. The most widely used method to determine organic P in sediments is NaOH–EDTA extraction followed by 31P-NMR detection. However, some organic P compounds are difficult to extract using NaOH–EDTA due to the low solubility, thus can not be detected by 31P NMR. Here, we used foam separation to determine organic P in sediment of North Canal of Tianjin City, China. Organic P was first enriched using foam separation coupled with NaOH extraction. The enriched organic P was then analyzed with 31P NMR. The results showed that, compared with the traditional extraction method, foam separation coupled with NaOH extraction enriched more P compound because 31P NMR detected an extra signal of teichoic acid at chemical shift 1.14. This teichoic acid signal was not detected in the extract prepared using only NaOH–EDTA. Our finding demonstrates that determination using foam separation followed by 31P NMR is feasible.  相似文献   

10.
Many studies comparing the behaviour of individuals of different genders or species showed that animal body mass and forage quality/quantity are key elements of the foraging ecology of herbivores. Since body mass could also influence the animal’s sensitivity to predation risk, its vigilance behaviour should consequently be affected. Alpine ibex (Capra ibex) is characterised by a strong dimorphism among males of different ages, thus representing an ideal case study for testing the Jarman-Bell principle, avoiding possibly misleading effects resulting from the comparison between different species or genders. We analysed the fine-scale foraging behaviour of male ibex in order to assess the effect of body mass and the effects of vegetation quality/quantity on both foraging and vigilance behaviour. Our results showed that smaller males were more selective than larger ones, on account of their lower capability of digesting plant. Smaller males scanned the environment more frequently than larger ones. Male ibex grazed more selectively in sites with high quality forage and their bite rate increased as forage biomass decreased. Vigilance frequency increased with increasing forage biomass as, under these circumstances, ibex are able to prolong anti-predator vigilance while chewing bites that have already been cropped. Our findings highlight the effects of body mass per se on both foraging and anti-predator behaviours in herbivores, thus supporting the Jarman-Bell principle. Foraging can arguably be considered a very flexible behaviour with high evolutionary relevance as it enables herbivores to optimally adjust their total energy intake under varying conditions of food resources.  相似文献   

11.
Our understanding of the reproductive biology of corals from the Mexican southeastern Pacific is limited, and consequently, the role of reproduction in structuring coral communities is unclear. As a first attempt to understand the importance of sexual reproduction in structuring and maintaining of the coral communities from this region, we documented the reproductive cycles over 2 years (2003–2004) in three main reef-building corals species in the region. Pocillopora damicornis was shown to be hermaphroditic with asynchronous gamete development observed only in 2004; P. gigantea was characterized as both gonochoric and cosexually hermaphroditic. Absence of mature gametes was documented in both species, and an observation may be attributed to the 2003 El Niño Southern Oscillation event, which may have inhibited reproductive maturation via thermal stress. Porites panamensis was gonochoric with asynchronous development, and planulae were generally brooded. The presence of mature gametes and planulae in P. panamensis polyps suggests that this species is an important contributor to local and, likely, regional recruitment of this species. Further research should seek to identify important source populations for these coral recruits and document the exchange of larvae between coral populations of the Mexican Pacific.  相似文献   

12.
13.
B. Czeczuga 《Marine Biology》1972,13(2):124-126
Investigations have been carried out on the carotenoids in Anemonia sulcata (Pennant) and Actinia equina (L.) (Coelenterata: Anthozoa) from the Adriatic Sea. The presence of the carotenoids was determined by means of columnar and thin-layer chromatography. The following carotenoids were found: Anemonia sulcata: β-carotene, lutein-like (epoxy and free) and astaxanthin; Actinia equina: α-carotene, β-carotene, actinioerythrin, lutein-like (?) and astaxanthin (ester and free).  相似文献   

14.
Environmental conditions greatly impact the dynamics of host–pathogen relationships, affecting outbreaks and emergence of new diseases. In corals, epizootics have been a main contributor to the decline of reef ecosystems and rising sea surface temperatures associated with climate change are thought to exacerbate virulence of pathogens and/or compromise the immune responses of coral hosts. Among pathogens strategies, protease secretion is a common virulence factor that promotes colonization of the host. As such, protease inhibitors play an invaluable role to the host for protection against pathogen invasion. This study describes changes in activity of proteases secreted by the fungal pathogen, Aspergillus sydowii, and protease inhibitors of Gorgonia ventalina under ambient and elevated temperatures and health conditions (disease and healthy). G. ventalina colonies were collected from Florida Keys, Florida (24° 34.138N, 81° 22.905W) or La Parguera, Puerto Rico (17° 56.091N, 67° 02.577W) in 2007 and 2012, respectively. At elevated temperatures, protease activity was significantly higher than at ambient temperatures in A. sydowii. Temperature stress did not induce a change in protease inhibitor activity, but in healthy G. ventalina colonies, inhibitor activity against proteases was higher than in diseased individuals. Healthy colonies appear capable of resisting proteolytic activity, but diseased individuals are still likely affected by pathogen infections. These data suggest that rising sea surface temperatures due to climate change may increase levels of virulence (protease activity) of A. sydowii, while immunity (protease inhibitor) of G. ventalina may not be affected.  相似文献   

15.
Gobiid fishes of the genus Gobiodon live in strong association with certain reef-building corals that vary considerably in size and architecture. These fishes hence are excellent model systems for studying evolutionary adaption to specific microhabitats. Using a sample of Gobiodon histrio and G. rivulatus and their most important host corals (Acropora digitifera and A. gemmifera) from the northern Red Sea, we assess (1) how corals that are occupied by gobies differ in their architecture from colonies that are not occupied and (2) how fish body shape is associated with the architecture of their host coral. Fish body shape was assessed by geometric morphometric techniques. Coral measurements included colony size, branch length (BL), and interbranch as well as branch tip distance of adjacent branches, for which we applied a new and non-destructive measurement technique based on casts of two-component epoxy resin. The most important factor influencing the occupation of corals was a BL of more than 5 cm. The distance between coral branches was clearly related to the width of the fishes and hence constrained overall fish size. G. histrio and G. rivulatus differ in adult body shape as well in their allometric development of lateral body compression, resulting in different maximum body sizes attainable in the restricted interbranch space of corals. The strong dependence of coral-associated fishes on large coral colonies with specific architectures increases the extinction risk of fishes within deteriorating coral reefs.  相似文献   

16.
Epizoic worms were found to occur on certain coral colonies from reefs off the coast of Eilat (Red Sea). We identified 14 coral species infested by acoelomorph worms at a depth range of 2–50 m. The host corals were all zooxanthellate and included both massive and branching stony corals and a soft coral. Worms from all hosts were identified as belonging to the genus Waminoa and contained two distinct algal symbionts differing in size. The smaller one was identified as Symbiodinium sp. and the larger one is presumed to belong to the genus Amphidinium. Worm-infested colonies of the soft coral, Stereonephthya cundabiluensis, lacked a mucus layer and exhibited distinct cell microvilli, a phenotype not present in colonies lacking Waminoa sp. In most cases, both cnidarian and Acoelomorph hosts displayed high specificity for genetically distinctive Symbiodinium spp. These observations show that the epizoic worms do not acquire their symbionts from the “host” coral.  相似文献   

17.
Three procedures for the extraction of coral lipids were compared and a rapid and effective method for future use is suggested. This method was used to measure the lipid content of the branching coral Porites porites (Pallas) and the massive corals Montastrea annularis (Ellis and Solander) and Siderastrea siderea (Ellis and Solander) during July and August 1991. P. porites and M. annularis were sampled on two fringing reefs, each characterised by different water quality affecting light transmission, and at depths of down to 30 m on a barrier reef on the west coast of the island. m. annularis contained, on average, 29% of dry weight as lipid, and there were no significant differences in lipid levels between corals sampled on either fringing reef at 3 and 6 m, or between fringing reefs and the barrier reef at 13, 20 or 30 m depth. Five samples were also taken from a single massive colony of S. siderea at 3 m on a fringing reef and at 13, 20 and 30 m depth on the barrier reef. Values for lipid ranged from 26 to 35% of dry tissue weight. P. porites from 3 and 6 m depth on both fringing reefs contained the same amount of lipid (11% of dry tissue weight). However, at 13 m depth on the barrier reef this coral contained significantly less lipid (8.5% of dry tissue weight). This difference may be attributable to a higher nutritional intake by P. porites on the fringing reefs.  相似文献   

18.
This is the first quantitative study on the prevalence of epizoic Waminoa sp. acoel worms and their association with corals in the Wakatobi Marine National Park (WMNP), South-East Sulawesi, Indonesia. Three replicate transects were laid on the reef crest, flat and slope at six sites in 2006 and eight sites in 2007. Four of the sites were common in both years. In total 69 transects were surveyed in 2006, and 87 transects in 2007. A total of 4.8% of all observed hard corals were associated with acoel worms in 2006 and 2.6% of hard and soft corals in 2007. Acoels were present on 16 and 21 of the coral taxa studied in 2006 and 2007 respectively. The worms were strongly associated with the azooxanthellate coral Tubastrea spp. and were rare or absent on the most abundant coral genera Montipora and Porites. The mean number of corals having acoels was highest on reef slopes, whereas acoels were virtually absent on reef flats. Corals that had a high and a medium cover of worms were more common in 2007 than in 2006. No significant trend in the adaptation of the zooxanthellae of Waminoa sp. to different depths at different sites was revealed. The impact of the worm on the coral is unknown, but high numbers may have a shading effect and a negative impact on the coral’s photophysiology. This acoel merits more study of its life cycle, its photophysiology, and its impact on its host corals. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

19.
Coral reef lagoons are generally regarded as zones of net heterotrophy reliant on organic detritus generated in more productive parts of the reef system, such as the seaward reef flat. The abundance and biomass of sediment infauna were measured seasonally for one year (1986) within the lagoon of Davies Reef, central Great Barrier Reef, to test the hypothesis that macrofaunal biomass and production of coral reef lagoons would decrease with distance from the reef flat and would change seasonally. In general, there were no simple relationships between infaunal standing stock or production and distance from the reef flat or season. Bioturbation by callianassid shrimps negatively affected the abundance of smaller infauna, suggesting a community limited by biogenic disturbance rather than by supply of organic material. Polychaetes and crustaceans were dominant amongst the smaller infauna (0.5 to 2mm) while larger animals (> 2 mm) were mostly polychaetes and molluscs. Mean biomass of infauna at both sites and all seasons was 3 181 mg C m?2. The smaller animals (0.5 to 2 mm) contributed about 40% of total macrofaunal respiration and production although they represented only 15% of the total macrofaunal biomass. The biomass of macrofauna was about equal to that of the bacteria and meiofauna, while respiration represented 10 to 20% of total community respiration. Consumption by macrofauna accounts for only 3 to 11% of total organic inputs to sediment, with a further 14 to 17% being lost by macrofaunal respiration.  相似文献   

20.
Laboratory 45Ca-incorporation rates in hermatypic coral skeletons have previously been used successfully as an index of physiological function. This laboratory method would become more meanigful if it also provided an absolute measure of coral growth rates. In two coral species, Porites compressa and Pocillopora damicornis, 45Ca incorporation rates were obtained from short (0.5 h) laboratory incubations using apical (determined as fast growing) portions of freshly collected coral branches. 45Ca exchange across the coenosarc was not significant and not corrected for, whereas diurnal fluctuation in 45Ca in Pocillopora damicornis was significant and a necessary correction. A calculated surface area is used to express calcification rate. Typical growth rates calculated from the 45Ca-incorporation rates were 20 and 6 mm/year for Porites compressa and Pocillopora damicornis, respectively. These rates are considerably higher than those previously obtained in the laboratory, and compare favorably with field growth rates — 24 and 14 mm/year, respectively.  相似文献   

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