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1.
《Marine pollution bulletin》2009,58(6-12):707-715
Sixteen sediment samples collected from eight transects in a mangrove swamp of the Jiulong River Estuary, Fujian, China were investigated for their content of polycyclic aromatic hydrocarbons (PAHs) and the biodegradation potential of the indigenous microorganisms. The bacterial community structures in the mangrove sediments and in enrichment cultures were also investigated. The results showed that the total PAHs concentration of mangrove sediments ranged from 280 to 1074 ng g−1 dry weight, that the PAHs composition pattern in the mangrove sediments was dominated by high molecular weight PAH components (4–6 rings), and that Benzo[ghi]perylene and Indeno[1,2,3-cd]pyrene were the most dominant at different stations. Abundant PAH-degrading bacteria were found in all the stations, the values of phenanthrene-degrading bacteria ranged from 5.85 × 104 to 7.80 × 105 CFU g−1 dry weight, fluoranthene-degrading bacteria ranged from 5.25 × 104 to 5.79 × 105 CFU g−1 dry weight, pyrene-degrading bacteria ranged from 3.10 × 104 to 6.97 × 105 CFU g−1 dry weight and the benzo(a)pyrene-degrading bacteria ranged from 5.25 × 104 to 7.26 × 105 CFU g−1 dry weight. DGGE analysis of PCR-amplified 16S rDNA gene fragments confirmed that there was a remarkable shift in the composition of the bacterial community due to the addition of the different model PAH compound phenanthrene (three ring PAH), fluoranthene(four ring PAH), pyrene(four ring PAH) and benzo(a)pyrene(five ring PAH) during enrichment batch culture. Eleven strains were obtained with different morphology and different degradation ability. The presence of common bands for microbial species in the cultures and in the native mangrove sediment DNA indicated that these strains could be potential in situ PAH-degraders. 相似文献
2.
Recent studies have shown that polychlorinated biphenyl (PCB) levels are high in coastal sites. Various types of deposition events, including dry deposition, air–water exchange and wet deposition, were analyzed as part of the study to illustrate the pollution level. The atmospheric levels and deposition mechanisms of 82 PCBs were investigated in Mudanya, a coastal city in Turkey. A total of 175 samples and 112 blanks were collected. Air–water exchange and particle phase dry deposition fluxes were 120 ± 90 ng/m2-d and 125 ± 160 ng/m2-d, respectively. The wet-dry deposition sampler (WDDS) consisted of two reservoirs, wet and dry. Collected with the WDDS, the dry deposition flux was 21 ± 20 ng/m2-d, and the wet deposition fluxes (during the rainy period) were 145 ± 130 ng/m2-d and 195 ± 270 ng/m2-d for the dissolved and particulate phases, respectively. Mass transfer coefficients (MTCs), dry deposition velocities and washout ratios were calculated and compared with the literature values. 相似文献
3.
《Marine pollution bulletin》2012,64(5-12):459-463
Seawater samples (including surface water and bottom water) were collected from the Western Taiwan Strait (WTS) during June 24–25, 2009; polycyclic aromatic hydrocarbons (PAHs) in dissolved phase and particulate phase were analyzed, respectively. The results showed that the total concentrations of PAHs in the dissolved phase and particulate phase were ranged from 12.3 to 58.0 ng L−1, and 10.3–45.5 ng L−1, which showed a low-middle contamination level in the China Seas. The spatial variability of PAHs may be related to the complicated currents of WTS, especially the Min-Zhe coastal current. PAHs diagnostic ratios suggested that PAHs mainly originated from the inputs of pyrolytic (combustion) sources, which might be contributed to land-based atmospheric deposition. The particle-water partition coefficients of individual PAH showed that partitions were not correlated with suspended particulate matter content, dissolved organic carbon or salinity, similar to the Yangtze coastal area. 相似文献
4.
《Marine pollution bulletin》2012,64(5-12):417-423
Sediment samples were collected from 12 locations of Kaohsiung Harbor, Taiwan and analyzed for polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations varied from 472 to 16,201 ng g−1 dry weight. The highest PAH concentrations were from the industrial zone docks situated in south Kaohsiung Harbor. Diagnostic ratios showed that the possible source of PAHs in the industrial zone dock could be coal combustion while in the other zones it could be petroleum combustion. The toxic equivalent concentrations (TEQcarc) of PAHs varied from 55 to 1964 ng TEQ g−1 dry weight. Higher total TEQcarc values were found at industrial zone docks (from 1404 to 1964 ng TEQ g−1 dry weight). As compared with the US Sediment Quality Guidelines (SQGs), the observed levels of PAHs at industrial zone docks exceeded the effects range low (ERL), and could thus cause acute biological damage. However, the lower levels of PAHs at the other zones would probably not exert adverse biological effects. 相似文献
5.
《Limnologica》2017
The high plant richness in riparian zones of tropical forest streams and the relationship with an input of organic matter in these streams are not well understood. In this study, we assessed (i) the annual dynamics of inputs of coarse particulate organic matter (CPOM) in a tropical stream; and (ii) the relationship of species richness on riparian vegetation biomass. The fluxes and stock of CPOM inputs (vertical-VI = 512, horizontal-HI = 1912, and terrestrial-TI = 383 g/m2/year) and the benthic stock (BS = 67 g/m2/month) were separated into reproductive parts, vegetative parts and unidentified material. Leaves that entered the stream were identified and found to constitute 64 morphospecies. A positive relationship between species richness and litterfall was detected. The dynamics of CPOM were strongly influenced by rainfall and seasonal events, such as strong winds at the end of the dry season. Leaves contributed most to CPOM dynamics; leaf input was more intense at the end of the dry season (hydric stress) and the start of the rainy season (mechanical removal). Our study show an increase of litter input of CPOM by plant diversity throughout the year. Each riparian plant species contributes uniquely to the availability of energy resources, thus highlighting the importance of plant conservation for maintaining tropical streams functioning. 相似文献
6.
《Marine pollution bulletin》2014,78(1-2):224-229
The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in the sediment from the Hormuz strait, Persian Gulf. The sum of 16 PAHs (ΣPAH) concentrations varied from 72.17 to 277.77 ng g−1 dry weight, with an average value of 131.20 ± 59.29 ng g−1 dry weight. An ecological risk assessment of PAHs, indicated that adverse biological effects caused by acenaphthene and acenaphthylene occasionally may take place in the sediment of Hormuz strait. PAH source identification showed that the PAHs in the sediments come from pyrogenic and mixed origin. Based on classification of pollution levels, sediments from Hormuz strait could be considered as low to moderately polluted with PAHs. 相似文献
7.
《Marine pollution bulletin》2012,64(5-12):528-534
The Salt-water River watershed is one of the major river watersheds in the Kaohsiung City, Taiwan. Water quality and sediment investigation results show that the river water contained high concentrations of organics and ammonia–nitrogen, and sediments contained high concentrations of heavy metals and organic contaminants. The main pollution sources were municipal and industrial wastewaters. Results from the enrichment factor (EF) and geo-accumulation index (Igeo) analyses imply that the sediments can be characterized as heavily polluted in regard to Cd, Cr, Pb, Zn, and Cu. The water quality analysis simulation program (WASP) model was applied for water quality evaluation and carrying capacity calculation. Modeling results show that the daily pollutant inputs were much higher than the calculated carrying capacity (1050 kg day−1 for biochemical oxygen demand and 420 kg day−1 for ammonia–nitrogen). The proposed watershed management strategies included river water dilution, intercepting sewer system construction and sediment dredging. 相似文献
8.
Chloride (Cl−) in urban waterways largely originates from runoff containing deicing salts. Cl− is retained in watersheds after deicing ends, resulting in deleterious effects on aquatic biota. Stormwater management ponds (SWMPs), designed to mitigate ‘flashy’ urban runoff response, are known to impact pollutant transport. However, there is little information on what role SWMPs play in the timing and magnitude of Cl− transport over different timescales. This study quantifies the mass of Cl− retained in two SWMPs over varying timescales. Both ponds are in an urbanizing watershed in south-central Ontario; one drains a commercial area, the other, a residential area. High frequency measurements of water level and specific conductivity, from which flow and Cl− concentration were derived, were taken with sensors at pond inlets and outlets. For one SWMP, data were also collected upstream and downstream of the confluence of the pond outflow and the receiving creek to quantify the in-stream response to Cl−-laden pond outflows. The findings suggest that SWMPs likely play a role in watershed-scale Cl− retention; one SWMP consistently retained Cl− while the other had variable retention and release of Cl−. In the receiving creek, Cl− concentrations downstream of the pond exceeded the acute toxicity threshold for aquatic organisms twice as often as concentrations upstream of the pond, and Cl− pulses corresponded to Cl− release events from the pond. The results of this study suggest that SWMPs concentrate spatially distributed salt inputs and modify the timing and magnitude of their release to receiving streams. Stream reaches that receive water inputs from SWMPs may be more vulnerable to Cl− toxicity than reaches that do not receive flow via SWMPs. The results of this study will help parameterize the role of SWMPs in watershed-scale Cl− transport models and geospatial models of salt vulnerable areas. 相似文献
9.
Most rivers in Italy are segmented by dams that need rehabilitation because of (1) safety requirements by increasingly risk-averse societies, (2) changes in the downstream river and riparian system after dams building, (3) poor initial design at the time of completion and (4) modified priorities of watershed management. Safe design of flood spillways is a major concern, and requires to cope with low frequency flood hazard. One must estimate flood figures with high return periods (R ⩾ 1000–10,000 years) but statistical methods involve large uncertainties because of the short length of the available records. This paper investigates the return period of the design flood of existing spillways RS of large dams in Italy. We used re-normalized flood frequency approach and regionalization using the Generalized Extreme Value distribution. The estimation of the site specific index flood is carried out by simple scaling with basin area at the regional level. The result show that 55% (245) of the 448 examined dams are equipped by spillway with RS > 10,000; and 71% (315) of the dams have RS > 1000. Conversely, 29% (130) of the dams display RS < 1000 years, lower than acceptable hazard. The spillway of 14% (62) of the dams has RS < 100 years, indicating potential exceedance of spillways capacity. Reservoir routing may dampen the outflow hydrograph, but one should carefully account for the need of achieving accurate dam safety assessment of these dams based on site specific investigations, also accounting for global change forcing. 相似文献
10.
《Marine pollution bulletin》2014,78(1-2):77-84
The distributions of 41 polychlorinated biphenyls (PCBs) were determined in the aqueous phase, suspended particulate matter (SPM), and sediment of the Daliao River estuary in Liaodong Bay, Bohai Sea (China). The total PCB concentrations ranged from 5.51 to 40.28 ng L−1 in the surface water, from 6.78 to 66.55 ng L−1 dry weight in the SPM, and from 0.83 to 7.29 ng g−1 dry weight in the sediment. The PCB concentrations in water, SPM, and sediment were moderate relative to those reported for other estuary and marine systems around the world. Sedimentary PCB concentrations decreased offshore due to the active deposition of laterally transported river-borne particles. The predominance of the highly chlorinated congeners for the water, SPM, and sediment samples are an indication of either a lack of degradation or the presence of nearby or recent releases into the environment. 相似文献
11.
The investigation focuses on the analysis of dissolved sulfonamides, tetracyclines, analgesics, anticonvulsants and hormones in surface water. Runoff event and baseflow samples were analysed in two small river catchments of different land use in Luxembourg. For most of the flood events, similar pollutant loads to those transported during 1 day with average baseflow discharge were observed. The maximum contents during flood events and the event mean concentrations are controlled by pre‐event hydro‐climatological conditions. For all substances under investigation, maximum concentrations and event mean concentrations show a decrease with raising antecedent rainfall. In addition, the interstorm and intrastorm variability of the pollutant transport was determined. Runoff generation and corresponding transport of xenobiotic compounds show a complex pattern with many interrelated processes, taking place within bedrock, soil, anthropogenic facilities and channel and in different parts of the basins under investigation. Different sources of pollutants can be identified and related to particular locations in the basin. The influence of the sewer systems is obvious. In the agricultural Mess basin, higher rainfall amounts lead to greater quantities of laterally inflowing soil water with higher concentrations of dissolved oxytetracycline. This originates from veterinary medicines administered to livestock and enters the environment through the application of organic fertilisers, especially by slurry that is applied to the fields. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
12.
Numerical simulation of laboratory experiments in detention pond routing with long rainfall duration
Yao-Ming HONG 《国际泥沙研究》2008,23(3):233-248
This paper establishes a numerical detention pond volume model based on the hydrological continuity equation and the Runge-Kutta numerical method. Experiments for the conditions of both steady and unsteady flow have been used to verify the model. In unsteady flow cases, the outflow hydrograph by numerical simulation are fairly consistent with experimental value. Both experimental and numerical results indicate that wider rectangular sharp-crested weirs or larger rectangular slot tend to induce greater outflow discharges, which undesirably cut down the detention volume. Experiments show that the necessary detention volume of rectangular slot is smaller than that of the rectangular sharp-crested weir for a constant flood peak reduction. That is, the rectangular slot is the recommended outflow device when flood peak reduction is the design criteria. The study also shows that necessary detention volume of the short rainfall duration is less than that of the long rainfall duration under constant allowable maximum discharge. 相似文献
13.
Optical dating of a hyperconcentrated flow deposit on a Yellow River terrace in Hukou,Shaanxi, China
Jia-Fu Zhang Wei-Li Qiu Xiao-Qing Wang Gang Hu Rong-Quan Li Li-Ping Zhou 《Quaternary Geochronology》2010,5(2-3):194-199
A sand layer, interpreted as a hyperconcentrated flow deposit, was found interbedded between loess on a Yellow River terrace in Hukou, Shaanxi, China. The site is known as the Longwangchan Palaeolithic site. The deposits from the terrace were dated using optically stimulated luminescence (OSL). Two samples from the sand layer were dated to 30 ± 2 and 33 ± 3 ka using coarse-grained (CG) quartz, and to 82 ± 7 and 94 ± 5 ka using fine-grained (FG) quartz, respectively. The CG quartz OSL ages are believed to be reliable on the basis of the OSL ages of the bracketing loess samples. The overestimation of the FG quartz OSL ages of the sand samples is explained in terms of hyperconcentrated flow processes during sediment transport and deposition. The large difference between the CG and FG quartz OSL ages of the sand samples helps to better understand the formation of the hyperconcentrated flow deposit. The hyperconcentrated flow deposit in this study indicates an extreme river flood occurring at ～30 ka in this area. In addition, the stone artifacts found in the lower loess layer overlying the bedrock of the terrace were dated to ～47 ka. 相似文献
14.
《Continental Shelf Research》2007,27(3-4):489-505
Sediment accumulation over the past century on the continental shelf near the Po delta varies with distance from the most active distributary channels. Near the Pila and Goro distributaries, sediment accumulation is rapid (1–4 cm yr−1) and occurs in pulses. In these areas, the seabed is dominated by physical sedimentary structures that can be related to flood sedimentation. Between the two distributaries and in the southern portion of the dispersal system, sediment accumulation is slower (rates reach a minimum of 0.23 cm yr−1 at ∼50 km from the Pila mouth) and steady-state, reflecting more continuous dispersal of sediment during non-flood periods. Sedimentary strata in these locations are composed of finer (clayey silt), mottled sediment. The similarity in the spatial distribution of long-term (100-yr) sediment accumulation to deposition resulting from the 2000 flood event suggests that the Po shelf is flood-dominated.About half of the sediment delivered by the Po River on a 100-yr time scale can be accounted for in the seabed deposit within ∼50 km of the Pila mouth. The remaining sediment is likely transported southward by the prevailing circulation, and this sediment coalesces with inputs from the Apennine Rivers. 相似文献
15.
《Marine pollution bulletin》2009,58(6-12):419-424
In 2006, organotins pollution were investigated in the coastal environment of Xiamen, China. Six species of organotin compounds including tributyltin, triphenyltin and their degradation compounds were quantified in the dissolved and particulate phases of the water, and in the sediment using GC-FPD. The concentrations of organotin compounds ranged from 2.2 to 160 ng (Sn) L−1 dissolved in the water, 0.14–6.7 ng (Sn) L−1 in suspended particulate matter and nd ∼ 26 ng (Sn) g−1 (dry weight) in the sediment. The highest concentration of total organotin or tributyltin in water was found in a shipyard and at a station near the inlet of the harbor, indicating fresh inputs of antifouling paints to Xiamen’s coastal environment. Organotin speciation was performed on sediment cores to investigate contamination trends over the past ten years in the harbor. The results of 210Pb dating indicated that Xiamen western harbor suffered contamination during 2000. The environmental behavior of organotins such as the enhancement of the microlayer, partitioning between water/suspended particulate matter and between water/sediment are also discussed in this paper. 相似文献
16.
Ana Cecília Rizzatti de Albergaria-Barbosa Vinicius Faria Patire Satie Taniguchi Wellington Silva Fernandez June Ferraz Dias Márcia Caruso Bícego 《Marine pollution bulletin》2017,114(1):609-614
This work aimed to evaluate the use of Mugil curema as a biomonitor for polycyclic aromatic hydrocarbon (PAH) bioavailability. Fish biliary metabolites from low-contaminated (Cananéia) and contaminated (Santos) Brazilian estuaries were analysed using a high-performance liquid chromatography apparatus coupled to fluorescence detectors connected in a series. In the Cananéia and Santos estuaries, total metabolite levels ranged from 0.85 to 34.4 μg g? 1 of bile and from 4.06 to 528 μg g? 1 of bile, respectively. Metabolite levels were not influenced by feeding status or sexual hormones (p < 0.05), thus suggesting that M. curema is a good biomonitor for PAH bioavailability. In estuarine regions, it is possible to sample both the male and female genders of this species in any reproductive period. 相似文献
17.
《Marine pollution bulletin》2014,78(1-2):110-117
Sea microlayer (SML) and subsurface water (SSW) samples were collected around Xiamen Island to study the enrichment and partitioning of polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations ranged from 93.43 to 411.05 ng L−1 in the SML and 49.29–279.42 ng L−1 in the SSW. Compared with the results of previous studies before pollution control measurements, PAHs levels decreased significantly. The enrichment factors (EFs) of dissolved and particulate PAHs varied from 0.68 to 2.71 and 0.43–3.56. EFs showed the consistent enrichment trends with sites and exhibited different enrichment characteristics between 2 and 3 ring PAHs and 4 ring PAHs. Furthermore, the much higher concentrations of BaP (strong carcinogenicity) were accompanied by higher EFs in the SML samples from the Western Xiamen Harbour, which together indicated the risk of impacts to the fish eggs that usually float on the SML water after exposure to oil spills and combustion, contributed directly by the port and shipping activities. 相似文献
18.
《Marine pollution bulletin》2013,70(1-2):189-194
Irgarol 1051 is a common antifouling biocide and is highly toxic to non-target plant species at low ng/L concentrations. We measured up to 254 ng/L Irgarol in water and up to 9 ng/g dry weight Irgarol in sediments from Southern California recreational marinas. Irgarol’s metabolite, M1, concentrations were up to 62 ng/L in water and 5 ng/g dry weight in sediments. Another antifouling biocide, diuron, reached up to 68 ng/L in water and 4 ng/g dry weight in sediments. The maximum Irgarol concentrations in water were greater than the Irgarol concentration recommended as the plant toxicity benchmark (136 ng/L), suggesting that Irgarol concentrations may be high enough to cause changes in phytoplankton communities in the sampled marinas. Irgarol concentrations measured in sediments were greater than calculated Environmental Risk Limits (ERLs) for Irgarol in sediments (1.4 ng/g). Antifouling pesticide accumulation in sediments may present a potential undetermined risk for benthic organisms. 相似文献
19.
《Marine pollution bulletin》2009,58(6-12):838-845
Environmental impacts of vessels are well documented; Cu pollution as result of Cu based antifouling paints and nutrient pollution (such as N) from marine sewage are two examples of such disturbances. Understanding environmental impacts as well as the use of coastal waterways by recreational vessels is of concern to regulatory authorities, waterway users and local residents. In this study more than 55 aerial surveys were conducted of selected popular anchorages in eastern Moreton Bay, Queensland, Australia. Numbers of recreational vessels at certain times during the year were used in multiple linear regression analyses to develop predictive models for recreational vessel numbers. Over one year approximately 10,000 locally registered recreational craft (>6 m length overall) generated an estimated 59,000 vessel nights. With Cu leaching rates from the literature, and estimates of sewage inputs (assuming little or no use of pump-out facilities), load estimates associated with overnight use of 20 popular anchor sites were calculated as 141 ± 46 kg of Cu and 1.17 ± 0.38 t of nitrogen (N) annually. More importantly, the models showed vessel activity to be highly variable, and focused at peak holiday times, with 14% of vessel activity and associated pollutant loads entering the environment during Christmas and Easter. This study highlighted the inherent difficulties in managing a popular maritime amenity and Marine Parks such as the Moreton Bay Marine Protected Area, Queensland, Australia with its variety of stakeholders and types and intensities of uses. 相似文献
20.
《Limnologica》2017
This study tested the hypothesis that the flood pulse affects the diet composition and the niche breadth of Moenkhausia forestii, a small characid fish inhabiting the littoral zone of lakes. To this end, we compared the diet composition (at the population and individual levels) between hydrological periods (high and low water phases) in a floodplain lake of the Upper Paraná River. PERMANOVA revealed differences in the diet between periods (pseudoF1,38 = 8.5; p < 0.001), with predominant consumption of chironomid larvae and Ephemeroptera (aquatic resources) in the low-water period and an increase in the contribution of terrestrial resources (Hymenoptera, Coleoptera, and Orthoptera) during the high-water period. Based on the PERMDISP results, inter-individual variability in M. forestii diet also differed between periods (F1,38 = 5.80; p = 0.02), with higher values during the high-water period resulting in a dietary niche expansion. During the low-water period, we observed the dominance of chironomid larvae in the diets of most individuals, resulting in lower inter-individual variability and thus narrower niche breadth. The diet of M. forestii was affected by the flood pulse at both the population and individual levels. The most important difference was found in the origin of food items; during the low-water period, the diet consisted mainly of aquatic resources, and during the high-water period, there was a large contribution of terrestrial resources. This variation is related to the increased availability of allochthonous resources in the high period, when terrestrial areas are flooded by the overflow of the river, thereby increasing the input of resources into the aquatic environment. The increased availability of food resources during this period allowed the expansion of the trophic niche of M. forestii, accompanied by the highest richness (19 items) and the highest evenness of food items. Our findings demonstrated that the flood pulse affected the composition of the M. forestii diet at both the population and individual levels. These results support the importance of the flood pulse, which connects aquatic and terrestrial ecosystems, in providing food resources for fish. 相似文献