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591.
S. Chidambaram R. Thilagavathi C. Thivya U. Karmegam M. V. Prasanna AL. Ramanathan K. Tirumalesh P. Sasidhar 《Environment, Development and Sustainability》2017,19(3):1015-1040
The occurrence of arsenic in drinking water and its detrimental effects have drawn much attention in recent years. Several studies have been conducted in the deltaic plains of River Ganga, NE part of the India, and in other countries, but no systematic study was conducted in South India on occurrence of arsenic in groundwater. The main aim of this study is to determine the level of arsenic in groundwater and to understand the relation with other geochemical parameters of groundwater in the south-eastern coastal aquifer at Kalpakkam region, India. This region is represented by three different lithologies, viz. charnockites, flood plain alluvium and marine alluvium. Twenty-nine representative samples of groundwater were collected and analysed for major ions, metals and isotopes such as 2H and 18O. In addition, geophysical method was also attempted to understand the subsurface condition. The spatial variation in arsenic (As) indicates that higher concentration was observed around the landfill sites and irrigated regions, which was supported by geochemical, statistical and isotopic inferences. The variation in the As with depth, lithology and sources has been clearly brought out. Though the values of As does not exceed the drinking water permissible limit (10 mg/l), it has reached a near permissible level of 8.7 ppb. Hence, it is essential to understand the geochemical behaviour of As for a proper future management of the water resource in the study area. 相似文献
592.
I. V. Seryodkin V. A. Zaitsev Yu. K. Petrunenko D. A. Maksimova D. G. Miquelle 《Russian Journal of Ecology》2017,48(4):372-376
The role of the Siberian musk deer in the diets of the Amur tiger, brown bear, and Asian black bear has been studied in the Sikhote-Alin State Biosphere Reserve in 1992 to 2016. Information has been collected from 763 tiger feeding sites, and the contents of tiger feces have been analyzed. Radiotelemetry has been used to evaluate tiger–musk deer relationships. The musk deer accounted for 0.26% of all animal species found to be eaten by the tiger. Musk deer remains in feces of the tiger, brown bear, and Asian black bear occurred with frequencies of 1.3, 0.2, and 0.3%, respectively. A case of musk deer avoiding the presence of brown bear is described. 相似文献
593.
V. A. Terekhova V. K. Shitikov A. E. Ivanova K. A. Kydralieva 《Russian Journal of Ecology》2017,48(5):417-424
A methodology of substantiating the ecological risk of technogenic soil pollution has been described according to the results of bioindication using microfungal communities. At the first state, the values of the factors under which the frequency of each species is maximal were estimated using ordination methods. The statistical distribution of the species sensitivity was simulated according to these data. The methodology was illustrated using the results of analysis of the toxicity of soil samples from uranium mine dumps (the village of Kadzhi-Sai, Kyrgyzstan). The preliminary estimates of the critical values of six soil pollution indices that provide the defined allowable probability of the ecological risk have been given. 相似文献
594.
595.
Flora of the still unchanged or slightly modified floodplains is particularly valuable. Such are the natural, periodically flooded riparian ecosystems within the Mid-Pripyat river valley in Belarus. Distinctive elements of that area are ‘periodic islands’, which arise from the most elevated parts of the riverbed during flooding and have a specific microtopography. The aim of the research was to recognize floristic composition and ecological conditions of the ‘islands.’ Noted plants were mainly photophilous, by clearly varied in soil moisture, acidity and fertility requirements. 相似文献
596.
The relationship between the principle of free trade and nature conservation is one of the most acute and multifaceted problems in international business. The diversity of WTO activities implies the necessity of interdisciplinary studies utilizing the expertise and experience of specialists in international law and ecologists. In this paper, provisions of the WTO set of agreements and procedures for dispute settlement within the WTO framework are considered as applied to environmental protection. 相似文献
597.
Sebastian Hudjetz Henning Herrmann Catrina Cofalla Markus Brinkmann Ulrike Kammann Andreas Schäffer Holger Schüttrumpf Henner Hollert 《Environmental science and pollution research international》2014,21(24):13744-13757
There is a consensus within the scientific community that sediments act as a long-term sink for a variety of organic and inorganic pollutants, which, however, can re-enter the water column upon resuspension of deposited material under certain hydraulic conditions such as flood events. Within the implementation of the European Water Framework Directive, it is important to understand the potential short- and long-term impact of suspended particulate matter (SPM)-associated contaminants on aquatic organisms as well as the related uptake mechanisms for a sound risk assessment. To elucidate the effects of sediment-bound organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), rainbow trout (Oncorhynchus mykiss) were exposed to three resuspended natural sediments with different contamination levels. Physicochemical parameters including dissolved oxygen concentration, pH and temperature, total PAH concentration in sediments and SPM as well as different biomarkers of exposure in fish (7-ethoxyresorufin O-deethylase activity, biliary PAH metabolites, micronuclei, and lipid peroxidation) were measured following seven days of exposure within an annular flume, a device to assess erosion and deposition processes of cohesive sediment. Concentrations of PAHs in SPM remained constant and represented the different contamination levels in the un-suspended sediments. Significant differences in bile metabolite concentrations as well as in 7-ethoxyresorufin O-deethylase induction compared to control experiments (untreated animals and animals that were exposed in the annular flume without sediment) were observed for all exposure scenarios. The ratio between 1-hydroxypyrene in bile from fish exposed to the three different contamination levels was 1.0:3.6:10.7 and correlated well with (1) the ratio of pyrene concentrations in corresponding sediments which was 1.0:3.1:12.7 and (2) with the ratio of particle-bound pyrene in SPM which was 1.0:2.7:11.7. In contrast, hepatic lipid peroxidation and micronuclei formation represented the different contamination levels less conclusive. The results of this study clearly demonstrate that firmly bound PAH from aged sediments can become bioaccessible upon resuspension under flood-like conditions and are readily absorbed by aquatic organisms such as rainbow trout. Associated short-term effects were clearly documented and possible adverse long-term impacts due to genotoxicity are likely to follow. 相似文献
598.
Y. Schneider M. Beier K.-H. Rosenwinkel 《Environmental science and pollution research international》2014,21(20):12099-12108
Nitrous oxide (N2O), a strong greenhouse gas, can be produced by ammonium-oxidizing bacteria (AOB) as a by-product of ammonium oxidation and can potentially be formed in all types of nitrification processes. However, partial nitritation has been reported to cause significantly higher N2O emissions than complete nitrification. In the study presented here, the mechanisms and factors that drive N2O formation by AOB were investigated with respect to different operational strategies to achieve nitrite accumulation base on combined evaluation of oxygen uptake rate (OUR) and N2O formation rate. On the one hand, N2O formation during partial nitritation and nitrification in a continuously stirred tank reactor (CSTR) with continuous aerobic conditions was observed. On the other hand, the effect of intermittent aeration on N2O formation during nitrification was investigated. The presence of nitrite, the extend of sludge-specific ammonium loading, low oxygen concentration, and transition from aerobic to anoxic conditions significantly increased N2O formation in this reactor independently from each other, indicating that different formation pathways, supposedly via nitrite or hydroxylamine, were active. 相似文献
599.
Liina Kanarbik Irina Blinova Mariliis Sihtmäe Kai Künnis-Beres Anne Kahru 《Environmental science and pollution research international》2014,21(19):11320-11330
Estonia is currently one of the leading producers of shale oils in the world. Increased production, transportation and use of shale oils entail risks of environmental contamination. This paper studies the behaviour of two shale fuel oils (SFOs)—‘VKG D’ and ‘VKG sweet’—in different soil matrices under natural climatic conditions. Dynamics of SFOs’ hydrocarbons (C10–C40), 16 PAHs, and a number of soil heterotrophic bacteria in oil-spiked soils was investigated during the long-term (1 year) outdoor experiment. In parallel, toxicity of aqueous leachates of oil-spiked soils to aquatic organisms (crustaceans Daphnia magna and Thamnocephalus platyurus and marine bacteria Vibrio fischeri) and terrestrial plants (Sinapis alba and Hordeum vulgare) was evaluated. Our data showed that in temperate climate conditions, the degradation of SFOs in the oil-contaminated soils was very slow: after 1 year of treatment, the decrease of total hydrocarbons’ content in the soil did not exceed 25 %. In spite of the comparable chemical composition of the two studied SFOs, the VKG sweet posed higher hazard to the environment than the heavier fraction (VKG D) due to its higher mobility in the soil as well as higher toxicity to aquatic and terrestrial species. Our study demonstrated that the correlation between chemical parameters (such as total hydrocarbons or total PAHs) widely used for the evaluation of the soil pollution levels and corresponding toxicity to aquatic and terrestrial organisms was weak. 相似文献
600.
Major ionic compositions of fine particulate matter in an animal feeding operation facility and its vicinity 总被引:1,自引:0,他引:1
Qian-Feng Li Zifei Liu R.K.M. Jayanty Sanjay B. Shah Peter Bloomfield 《Journal of the Air & Waste Management Association (1995)》2014,64(11):1279-1287
Animal feeding operations (AFOs) produce particulate matter (PM) and gaseous pollutants. Investigation of the chemical composition of PM2.5 inside and in the local vicinity of AFOs can help to understand the impact of the AFO emissions on ambient secondary PM formation. This study was conducted on a commercial egg production farm in North Carolina. Samples of PM2.5 were collected from five stations, with one located in an egg production house and the other four located in the vicinity of the farm along four wind directions. The major ions of NH4+, Na+, K+, SO42?, Cl?, and NO3? were analyzed using ion chromatography (IC). In the house, the mostly abundant ions were SO42?, Cl?, and K+. At ambient stations, SO42?, and NH4+ were the two most abundant ions. In the house, NH4+, SO42?, and NO3? accounted for only 10% of the PM2.5 mass; at ambient locations, NH4+, SO42?, and NO3? accounted for 36–41% of the PM2.5 mass. In the house, NH4+ had small seasonal variations indicating that gas-phase NH3 was not the only major force driving its gas–particle partitioning. At the ambient stations, NH4+ had the highest concentrations in summer. In the house, K+, Na+, and Cl? were highly correlated with each other. In ambient locations, SO42? and NH4+ had a strong correlation, whereas in the house, SO42? and NH4+ had a very weak correlation. Ambient temperature and solar radiation were positively correlated with NH4+ and SO42?. This study suggests that secondary PM formation inside the animal house was not an important source of PM2.5. In the vicinity, NH3 emissions had greater impact on PM2.5 formation.
ImplicationsThe chemical composition of PM2.5 inside and in the local vicinity of AFOs showed the impact of the AFO emissions on ambient secondary PM2.5 formation, and the fate and transport of air pollutants associated with AFOs. The results may help to manage in-house animal facility air quality, and to develop regional air quality control strategies and policies, especially in animal agriculture-concentrated areas. 相似文献