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1.
以地处贵州中部的红枫湖水库为研究区,2010年的ALOS影像为基础,利用B3、B4(三波段和四波段)的乘积影像研究红枫湖水库库区表面的叶绿素a分布情况。结果表明,库区水体叶绿素a浓度在空间分布上呈现自三岔河入水口到北湖逐渐降低,沿岸边向湖中心逐渐降低的态势。探讨了适宜该库区的水体叶绿素a的提取方法,并引入基于费歇尔准则的最优分割算法,利用计算机编程实现了该库区叶绿素a分布水平的最优分划。这一系列针对该库区水体叶绿素a提取、分析和监测的优化方法,对该水源地的污染监测和库区的生态治理有一定的参考价值。  相似文献   

2.
巢湖入湖河流沉积物中有机磷的形态分级研究   总被引:2,自引:0,他引:2  
为识别巢湖流域污染物的特征、来源及其沉积物有机磷各形态分布与富营养化的关系,测定了7条巢湖入湖河流沉积物中有机磷各形态的含量,分析不同污染类型人湖河流沉积物中有机磷各形态分布的差异及与其他因素间的相关性。研究发现,不同污染类型人湖河流沉积物中水土保持控制型河流沉积物中有机磷各组分的相对含量顺序为残渣态Po〉富里酸-Po〉HCl-Po〉胡敏酸-Po〉NaHCO3-Po,平均的相对比例为7.5:3.1:1.9:1.5:1.0,而城市污染控制型和面源污染控制型河流沉积物中有机磷各组分的相对含量顺序恰好相同,面源污染控制型河流沉积物Po各形态含量低于城市污染控制型和水土保持控制型河流。中活性P。和OM、TP、Pi、Po、TN、NaHCO3-Pi、NaOH—Pi呈正相关,非活性Po与Po、NaOH-Pi呈显著正相关关系,反映了中活性Po很容易转化为生物可利用磷和非活性Po,且非活性Po仍然具有潜在的生物活性。  相似文献   

3.
巢湖入湖河流沉积物中有机磷的形态分级研究   总被引:2,自引:0,他引:2  
为识别巢湖流域污染物的特征、来源及其沉积物有机磷各形态分布与富营养化的关系,测定了7条巢湖入湖河流沉积物中有机磷各形态的含量,分析不同污染类型入湖河流沉积物中有机磷各形态分布的差异及与其他因素间的相关性。研究发现,不同污染类型入湖河流沉积物中水土保持控制型河流沉积物中有机磷各组分的相对含量顺序为残渣态Po >富里酸-Po >HCl-Po >胡敏酸-Po >NaHCO3-Po,平均的相对比例为7.5:3.1:1.9:1.5:1.0,而城市污染控制型和面源污染控制型河流沉积物中有机磷各组分的相对含量顺序恰好相同,面源污染控制型河流沉积物Po各形态含量低于城市污染控制型和水土保持控制型河流。中活性Po和OM、TP、Pi、Po、TN、NaHCO3-Pi、NaOH-Pi呈正相关,非活性Po与Po、NaOH-Pi呈显著正相关关系,反映了中活性Po很容易转化为生物可利用磷和非活性Po,且非活性Po仍然具有潜在的生物活性。  相似文献   

4.
The spatial distribution and bioaccumulation of organochlorine pesticides (OCPs) in surface sediments and benthic organisms from Taihu Lake were studied. OCPs were detected in all sediment samples with total concentrations ranging from 4.22 to 461 ng g−1 dry weight (dw). The ratios of certain metabolites to their parent compounds indicated there are still new inputs of parent DDT (dichlorodiphenyltrichloroethane) to Taihu Lake, while the highest residues of HCHs (hexachlorocyclohexanes) mainly came from earlier usage and fresh γ-HCH (lindane). No positive correlation was found between the distribution of OCPs and organic matter contents in sediments. Concentrations of OCPs and lipids in typical large benthic organisms, Bellamya aeruginosa (B. aeruginosa) and Corbicula fluminea (C. fluminea), increased with body weight. HCHs, DDTs, chlordanes and heptachlors were the dominant compounds detected in organisms and C. fluminea accumulated much more OCP than B. aeruginosa. Higher values of biota-sediment accumulation factor (BSAF) were detected in C. fluminea, which was both affected by biological characteristics of the organisms and physicochemical properties of the compounds.  相似文献   

5.
红枫湖是贵阳市重要的生活饮用水源地,20世纪90年代末期水体污染严重。从2008年开始进行综合治理,2011年起进入治理成效阶段。为了对治理成效期的水质状况有全面了解,为进一步污染治理和生态调控提供科学依据和对策,利用富营养化指数法和主成分分析方法对2011—2013年水体富营养化状态特征进行研究分析。结果表明:(1)在监测期,红枫湖始终保持中营养状态不变,但呈现逐年减弱的趋势,水质达标率逐年升高。(2)全湖的综合营养状态指数存在明显的时空异质性。(3)影响红枫湖水体质量的主控因子为叶绿素a、pH、透明度、总磷和高锰酸盐指数,总氮对其影响不显著。(4)在下一步治理中,继续加强外源性治理的同时,须加强水体内源性污染的治理工作,促进水质进一步好转。  相似文献   

6.
- Goal, Scope, Background. Lake Skadar is the largest lake in Balkan Peninsula, located on the Montenegro-Albanian border. The unique features of the lake and wide range of endemic and rare or endangered plant and animal species resulted in the classification of the Skadar as a wetland site of international significance. In spite of its importance the Lake is influenced by inflowing waters from river Morača and other regional rivers contaminated by the industry, municipal and agricultural activities in the area. Therefore, the Lake has been subject of various physical, chemical, biological and toxicological examinations. However, community-level analyses are most relevant to assess the effect of stressors on aquatic ecosystems. In the present study bacterial community structure among differently polluted sites of the lake was compared by genetic fingerprinting technique. Methods Water and sediment samples were collected from five differently polluted sampling sites on the Lake Skadar in spring and autumn of the same year. The bacterial community structure in the samples was characterized and compared by temporal temperature gel electrophoresis (TTGE) analysis of polymerase chain reaction-amplified bacterial 16S rRNA genes. Results and Discussion The TTGE analysis resulted in many distinguishable and reproducible band patterns, allowing reliable comparison of bacterial communities among sampling sites. Results on the bacterial community structure revealed that three of the selected locations can be considered as sites that have not shown any pollution degradation determined by our method, due to similar structure of bacterial community in the sediment samples. On the other hand, significant shifts in bacterial community structure in the mouth of the river Morača and Plavnica were shown. Since the results coincide with some of the bioassays and chemical analysis performed previously, the changes in bacterial community structure are explained as an effect of antropogenic pollution on the lake ecosystem by waters of river Morača and stream Plavnica. Conclusion The TTGE has proven to be an efficient and reliable method to monitor bacterial dynamics and community shifts in aquatic environment, especially in the sediments. Within the variety of environmental quality assessments the use of TTGE analyses of bacterial community is strongly recommended, particularly as an initial investigation. However, in any conclusion on the state of the environment, the TTGE results should be combined to some other biological, chemical and hydrological data. Recommendation and Outlook Since prokaryotes are a crucial group of organisms in the biosphere, the ecosystem function studies are largely based on bacterial communities. Therefore, bacterial community structure analysis should be a part of an integrated weight of evidence approach in pollution assessment. In case of Triad approach, consisting of chemical analyses, bioassays, and community studies in the field, the TTGE bacterial community structure analyses should be placed in the later Triad leg. In comparison to other community studies, based on various biotic indices, the TTGE bacterial community analysis has proven to be very sensitive, reliable and less time consuming.  相似文献   

7.
Li W  Shi Y  Gao L  Liu J  Cai Y 《Chemosphere》2012,89(11):1307-1315
This study investigated the presence and distribution of 22 antibiotics, including eight quinolones, nine sulfonamides and five macrolides, in the water, sediments, and biota samples from Baiyangdian Lake, China. A total of 132 samples were collected in 2008 and 2010, and laboratory analyses revealed that antibiotics were widely distributed in the lake. Sulfonamides were the dominant antibiotics in the water (0.86-1563 ng L−1), while quinolones were prominent in sediments (65.5-1166 μg kg−1) and aquatic plants (8.37-6532 μg kg−1). Quinolones (17.8-167 μg kg−1) and macrolides [from below detection limit (BDL) to 182 μg kg−1] were often found in aquatic animals and birds. Salvinia natans exhibited the highest bioaccumulation capability for quinolones among three species of aquatic plants. Geographical differences of antibiotic concentrations were greatly due to anthropogenic activities. Sewage discharged from Baoding City was likely the main source of antibiotics in the lake. Risk assessment of antibiotics on aquatic organisms suggested that algae and aquatic plants might be at risk in surface water, while animals were likely not at risk.  相似文献   

8.
The mercury distribution and speciation in the water column were investigated from November 2003 to September 2004. The distribution and concentrations of total mercury (THg) and particulate mercury (PHg) showed that algae had a large capacity to bind mercury in late spring (e.g. in May). It is shown that dissolved gaseous mercury (DGM) concentrations may also be affected by algae activities. The MeHg profile in the water column at a highly eutrophied site in Hongfeng Reservoir demonstrated that most of the MeHg was produced in the hypolimnion, whereas the MeHg profile pattern at another site with less eutrophication indicated that MeHg in water was largely ascribed to release from sediment. In September, the outflow of the reservoir was enriched with MeHg, which was 5.5 times higher than that in the inflows. The discharge of MeHg-concentrated water from the anoxic hypolimnion in the reservoir may pose a risk to downstream fauna.  相似文献   

9.
巢湖表层沉积物中重金属的分布特征及其污染评价   总被引:13,自引:1,他引:13  
以巢湖表层沉积物为研究对象,利用BCR连续提取法研究了沉积物中Cr、Co、Ni、Cu、Cd、Zn、V和Pb等8种重金属元素的分布特征,同时运用潜在风险指数法和地累积指数法综合评价了巢湖沉积物中重金属的生态风险。结果表明,巢湖沉积物中的重金属含量在空间上表现出东西高、中间低的分布特征。巢湖表层沉积物中Cr、Co、Ni、V和Cu 5种重金属都主要以残渣态为主,Zn和Cd主要以弱酸提取态为主,Pb以可还原态为主,同时,Co和Cu 2种元素的可交换态及可还原态含量占有较高比例,具有潜在危害性。相关性分析显示,Cr、Cu、Pb、Ni、Zn和Cd 6种重金属元素的来源和分布可能具有相似性,Co和V 2种重金属元素具有相似的地球化学行为且其主要来源可能与其他几种重金属不同。潜在生态风险指数评价结果表明,巢湖表层沉积物中8种重金属元素构成的生态危害顺序为:Cd>Pb>Co>Cu>Ni>Zn>V>Cr,Cd具有高的生态危害等级,其他7种重金属元素均为低生态危害等级。地累积指数法评价结果表明:巢湖沉积物重金属元素的富集程度为Cd>Zn>Pb>Co>Cu>V>Ni>Cr,Cr属于清洁级别,Co、Cu、V和Ni处于轻度污染水平,Zn和Pb处于偏中度污染,Cd达到了重污染水平。  相似文献   

10.
Thevenon F  Adatte T  Wildi W  Poté J 《Chemosphere》2012,86(5):468-476
This study investigates faecal indicator bacteria (FIB), multiple antibiotic resistant (MAR), and antibiotic resistance genes (ARGs), of sediment profiles from different parts of Lake Geneva (Switzerland) over the last decades. MARs consist to expose culturable Escherichia coli (EC) and Enterococcus (ENT) to mixed five antibiotics including Ampicillin, Tetracycline, Amoxicillin, Chloramphenicol and Erythromycin. Culture-independent is performed to assess the distribution of ARGs responsible for, β-lactams (blaTEM; Amoxicillin/Ampicillin), Streptomycin/Spectinomycin (aadA), Tetracycline (tet) Chloramphenicol (cmlA) and Vancomycin (van). Bacterial cultures reveal that in the sediments deposited following eutrophication of Lake Geneva in the 1970s, the percentage of MARs to five antibiotics varied from 0.12% to 4.6% and 0.016% to 11.6% of total culturable EC and ENT, respectively. In these organic-rich bacteria-contaminated sediments, the blaTEM resistant of FIB varied from 22% to 48% and 16% to 37% for EC and ENT respectively, whereas the positive PCR assays responsible for tested ARGs were observed for EC, ENT, and total DNA from all samples. The aadA resistance gene was amplified for all the sediment samples, including those not influenced by WWTP effluent water. Our results demonstrate that bacteria MARs and ARGs highly increased in the sediments contaminated with WWTP effluent following the cultural eutrophication of Lake Geneva. Hence, the human-induced changing limnological conditions highly enhanced the sediment microbial activity, and therein the spreading of antibiotic resistant bacteria and genes in this aquatic environment used to supply drinking water in a highly populated area. Furthermore, the presence of the antibiotic resistance gene aadA in all the studied samples points out a regional dissemination of this emerging contaminant in freshwater sediments since at least the late nineteenth century.  相似文献   

11.
以新型赤泥基多孔陶瓷滤球(porous ceramic filter material,PCFM)颗粒为吸附剂,采用动态和静态吸附实验相结合的实验方法研究了PCFM颗粒对沉积物磷的吸附性能。动态吸附实验结果表明,影响PCFM颗粒除磷效果的主要因素有投加量、反应时间、上覆水体pH值和环境温度,最佳吸附反应条件为PCFM投加量8 g,反应时间12 h,上覆水体pH=12,环境温度为50℃。静态吸附实验结果表明,随着反应时间的延长,PCFM对沉积物五种形态磷吸附在12 d左右接近或达到了吸附平衡,此时TP、OP、IP、Fe/Al-P和Ca-P的去除量分别为245.89、69.86、155.25、195.22和-49.01 mg·kg-1。可见PCFM对沉积物磷的吸附性能较好,可进一步应用于富营养化湖泊沉积物磷控制。  相似文献   

12.
A 5.3 m sediment core and soil samples were taken from Diss Mere and its catchment. The sediment core was dated and Hg analysed on the sediment and soil samples. The Hg record of the sediment core shows that Diss Mere has been contaminated for the past thousand years and the historical trends in sediment contamination are in good agreement with the development of the weaving industry in Diss and hemp cultivation in the region. Mercury contamination in Diss Mere has been significant and reached a peak in the mid-19th century with sediment Hg concentrations over 50 μg g−1. Elevated Hg concentrations were also found in contemporary soils in residential areas with former industrial land use. Although local hemp cultivation and the traditional weaving industry were abandoned a hundred years ago, Hg contamination caused by these activities still exists in the catchment, and affects the lake.  相似文献   

13.
Atmospheric phosphorus in the northern part of Lake Taihu, China   总被引:1,自引:0,他引:1  
Luo J  Wang X  Yang H  Yu JZ  Yang L  Qin B 《Chemosphere》2011,84(6):785-791
  相似文献   

14.
Phosphine migration at the water-air interface in Lake Taihu, China   总被引:1,自引:0,他引:1  
Han C  Geng J  Zhang J  Wang X  Gao S 《Chemosphere》2011,82(6):935-939
The diurnal atmospheric phosphine (PH3) concentrations and fluxes at the water-air interface in Lake Taihu were reported. The results showed that the PH3 flux at the water-air interface ranged from −69.9 ± 29.7 to 121 ± 42 ng m−2 h−1, with a mean flux of 14.4 ± 22.5 ng m−2 h−1. The fluxes were both negative and positive during the diurnal period, indicating that the lake can act as a sink and a source of PH3. In addition, the PH3 fluxes were positively correlated with water temperature, total soluble phosphorus and soluble reactive phosphorus, while they were negatively correlated with water redox potential. A similar diurnal variation curve of atmospheric PH3 concentrations was observed during all four seasons, with the maximum level occurring in early morning and the minimum appearing around midday. These findings suggest that light plays an important role in the elimination of atmospheric PH3. A significant positive correlation was also found between air temperature and atmospheric PH3 concentration. The mean flux of PH3 in Lake Taihu was higher than in other reported wetlands, with an estimated annual emission of PH3 to the atmosphere of 2.94 × 105 g y−1.  相似文献   

15.
湖北网湖位于长江中游,与长江干流相通,研究其沉积物中重金属分布特征及生态风险评价对长江经济带水质安全和水污染治理具有重要的意义。分析了网湖20个样点0~25 cm深度沉积物中As、Hg、Cu、Zn、Cd、Pb、Cr等7种重金属的质量分数和空间分布特征,利用相关分析和主成分分析探讨了表层沉积物中重金属的来源,并利用地累积指数法、潜在生态风险指数法和一致性沉积物质量基准进行重金属污染评价。结果表明:As、Hg、Cu、Zn、Cd、Pb、Cr等7种重金属的平均质量分数分别为37.5、0.137、108、123、0.283、37.8、108 mg·kg−1。与长江流域其他重要湖泊如巢湖、太湖等相比,网湖沉积物重金属含量处于较高水平。Pearson相关性分析表明,As、Zn、Cd两两之间呈极显著正相关 (p<0.01),这说明其具有同源性,分析主要来自于农业源;Cu和Pb之间也呈极显著正相关 (p<0.01),分析主要来源于交通运输污染源。重金属污染评价结果表明,沉积物整体受到极严重的重金属污染和很强的潜在生态危害,入湖区附近相对较严重,需及时防控和治理。一致性沉积物质量基准评价结果显示,Zn、Cd、Hg和Pb引发生物毒性的概率低于25%,As、Cu和Cr有25%~75%的概率产生有害生物效应。  相似文献   

16.
Organochlorine pesticides were determined in water and sediment samples collected from the littoral zone of Lake Prespa, as well as from its three main tributaries (the rivers Golema, Brajcinska and Kranska), during the period 2004 to 2006. In addition, muscle tissue samples of barbus fish (Barbus prespensis Karaman, 1928) collected from the littoral zone of Lake Prespa were also analysed. The obtained results give an overview of the contamination levels of these problematic compounds at their potential sources in the river mouths, in the potentially affected, species-rich littoral section of the lake and in the muscle tissue of one selected fish species, collected near the rivers’ deltas. Special attention was paid to the presence of some DDT metabolites (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′–DDE); (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (p,p′–DDD) and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p′–DDT). The extraction of pesticides from water samples was done by liquid-liquid partition in dichloromethane. For the sediment and fish tissue we used solid-liquid extraction. The extracted residues were analyzed on a gas chromatograph equipped with an electron capture detector (GC-ECD). The results of the respective studies indicated the presence of DDT metabolic forms in the samples of the three analysed matrixes. The highest levels of presence for these pollutants were found in the muscle tissue of the fish samples. The total DDTs content in the analysed muscle tissue samples range from 11.67 to 13.58 μg kg?1of fresh tissue. The average total DDTs content for the sediment samples were within the range of 2.32 to 4.17 μg kg?1 of dry sediment. Higher DDT metabolites content were found in the sediments collected from the rivers than in the samples from the littoral zone. The lowest average total concentrations of DDTs, on the other hand, were recorded in the water samples and ranged between 0.036 and 0.057 μg L?1. The obtained results indicated that the dominant metabolic form in the samples of the three investigated matrixes (water, sediment and fish tissue) from Lake Prespa was p,p′-DDE. There was a very good linear correlation in this study between the content of DDT's (total DDT metabolites) detected and the percentage of total organic material in the sediment. The detected concentrations are clearly below the toxicity thresholds; consequently, severe effects on the endemic species of Lake Prespa are not very likely.  相似文献   

17.
选取贵州草海重污染湖区,利用改性粘土钝化剂开展底泥原位钝化技术示范,对示范区内外主要水质参数、浮游生物和底栖动物等进行了对比监测与研究。结果表明:示范工程实施一年后钝化区水体氨氮(NH3-N)和总磷(TP)含量分别降低至对照区的29%和23%,水体溶解氧含量达9 mg·L-1以上,透明度显著增加;钝化区水体藻类总丰度降低40%以上,蓝藻所占比例大幅下降;钝化区沉水植物生长繁茂,水体自净功能明显增强,已形成草型清水生态系统。钝化区与对照区水体浮游动物、底栖水生生物种群及丰度无显著变化,表明钝化剂未对动物生长造成不良影响;原位钝化技术具有快速提升水体透明度和溶解氧含量、抑制底泥污染物释放、降低水体营养盐含量及抑制藻类生长等特点,且实施方便、成本低廉,在湖泊底泥污染治理和水体富营养化防治领域具有广阔应用前景。  相似文献   

18.
Liu X  Xu L  Chen Q  Sun L  Wang Y  Yan H  Liu Y  Luo Y  Huang J 《Chemosphere》2012,87(5):549-556
We collected three ornithogenic coral sand sedimentary profiles from Jinyin Island, Jinqing Island and Guangjin Island of Yongle archipelago, South China Sea and reconstructed the deposition flux of anthropogenic Hg over the past 700 years in the study area. On the whole, the anthropogenic Hg flux is relatively low; it remained at a low level before the Industrial Revolution with a small peak at about 1450-1550 AD, which may record the enhanced metallurgy activity in Ming Dynasty of China. During the 20th century, the deposition flux of anthropogenic Hg increased rapidly, but two troughs occurred during the periods around 1940s and 1970s, corresponding to the economic depression caused by World War II, Civil War in China (1945-1949), and the Culture Revolution (1966-1976) in China. Since the 1970s the deposition flux of anthropogenic Hg has been persistently increasing, apparently the result of fast economic development in East and Southeast Asia countries around South China Sea.  相似文献   

19.
杨昆  潘梅娥  杨荣  宋毅  孟超 《环境工程学报》2016,10(10):5407-5412
当前滇池水污染的治理措施主要关注农业面源污染和城市生活污水,忽视了城市化过程中不透水表面带来的城市面源污染问题。采用基于遥感、GIS的生态环境影响评估模型,分析了滇池流域不透水表面的水环境效应。结果表明:不透水表面面积增加可导致流域地表径流量增加以及水质下降,进而导致流域水环境问题日益严重;当子流域不透水表面覆盖率(ISC)控制在0%~8%时,流域水环境状况良好;当ISC增长到8%~23%时,流域水环境受到影响;超过23%时,将形成不可逆转的水体污染,流域水环境严重退化。根据滇池17个子流域的不透水表面覆盖率大小,提出了滇池流域的子流域分类规划与治理思路,详细列出了分类治理的具体措施。  相似文献   

20.
Sediment cores taken from Taihu Lake, East China were analyzed for polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polybrominated biphenyl ethers (PBDEs). The results showed a general sharp increase of HCH, DDT, PAH and PBDE concentrations in the surface layers, corresponding to a sedimentation time of 1980 and 1990 onward in the Meiliang Bay and Xukou Bay, respectively. The source of PAHs has largely transferred from petrogenic to pyrogenic origin, and good relationships were observed between sediment PAH concentrations and the regional gross domestic product. The sharp increase of DDTs in recent years may be related to the mobilization and migration of these chemicals from surface soil to lake sediment, as a result of enhanced soil run-off due to large scale land transform, as well as the contribution of current usage of dicofol and DDT-containing anti-fouling paints.  相似文献   

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