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941.
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
942.
Emmanuel Kumi Albert A. Arhin Thomas Yeboah 《Environment, Development and Sustainability》2014,16(3):539-554
The Rio+20 summit of the United Nations in Brazil in 2012 committed governments to formulate a set of sustainable development goals (SDGs) that would be integrated into the Millennium Development Goals (MDGs) following its expiration in 2015. This decision has pushed sustainable development agenda into the limelight of development once again. Meanwhile, we note that the development agenda of many developing countries has been dominated by neoliberal orientation driven by market reforms, social inequality, and a move towards enhancing the economic competitiveness of the supply side of the economy. In this paper, we discuss the relationship between neoliberal economic agenda and sustainable development. We do so by examining how neoliberal policies of privatisation, trade liberalisation and reduction in governments spending stand to affect the attainment of sustainable development ideals and their implications on the post-2015 Sustainable Development Goals. The paper then suggests that relying solely on the mechanisms of the market in governing and allocating environmental resources is necessarily insufficient and problematic and therefore calls for a new approach—one which goes beyond just recognising the interdependency among social, environmental and economic goals and places issues of equity and addressing unfavourable power relations at the centre of interventions aimed at achieving the ideals of sustainable development. 相似文献
943.
Consideration is given to changes in the vegetation and climatic conditions on the eastern slope of the Northern Urals in the second half of the Holocene as reconstructed on the basis of integrated palynological, botanical, paleocarpological, and radiocarbon analysis of material from a peat bog section in the floodplain of the Loz’va River. The results show that the northern taiga zone of the study region in the period between approximately 5000 and 700 years BP was occupied by forests of southern taiga facies, as the climate was significantly warmer than it is today. 相似文献
944.
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
945.
L. Kos K. Michalska J. Perkowski 《Environmental science and pollution research international》2014,21(21):12223-12232
The aim of our studies was to determine the efficiency of decomposition of non-ionic surfactant by the Fenton method in the presence of iron nanocompounds and to compare it with the classical Fenton method. The subject of studies was water solutions of non-ionic detergent Tergitol TMN-10 used in textile industry. Water solutions of the surfactant were subjected to treatment by the classical Fenton method and to treatment in the presence of iron nanocompounds. In the samples of liquid solutions containing the surfactant, chemical oxygen demand (COD) and total organic carbon (TOC) were determined. The Fenton process was optimized based on studies of the effect of compounds used in the treatment, doses of iron and nanoiron, hydrogen peroxide and pH of the solution on surfactant decomposition. Iron oxide nanopowder catalyzed the process of detergent decomposition, increasing its efficiency and the degree of mineralization. It was found that the efficiency of the surfactant decomposition in the process with the use of iron nanocompounds was by 10 to 30 % higher than that in the classical method. The amounts of formed deposits were also several times smaller. 相似文献
946.
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
947.
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
948.
Zeynep Kılıç Orhan Atakol Sümer Aras Demet Cansaran-Duman Pelin Çelikkol 《Journal of the Air & Waste Management Association (1995)》2014,64(1):115-123
The biosorption characteristics of Cu(II) ions from aqueous solution using Lobaria pulmonaria (L.) Hoffm. biomass were investigated. The biosorption efficiency of Cu(II) onto biomass was significantly influenced by the operating parameters. The maximum biosorption efficiency of L. pulmonaria was 65.3% at 10 mg/L initial metal concentration for 5 g/L lichen biomass dosage. The biosorption of Cu(II) ions onto biomass fits the Langmuir isotherm model and the pseudo-second-order kinetic model well. The thermodynamic parameters indicate the feasibility and exothermic and spontaneous nature of the biosorption. The effective desorption achieved with HCl was 96%. Information on the nature of possible interactions between the functional groups of the L. pulmonaria biomass and Cu(II) ions was obtained via Fourier transform infrared (FTIR) spectroscopy. The results indicated that the carboxyl (–COOH) and hydroxyl (–OH) groups of the biomass were mainly involved in the biosorption of Cu(II) onto L. pulmonaria biomass. The L. pulmonaria is a promising biosorbent for Cu(II) ions because of its availability, low cost, and high metal biosorption and desorption capacities.
Implications: Lobaria pulmonaria is a promising biosorbent for Cu(II) ions because of its availability, low cost, and high metal biosorption and desorption capacities. To the best of our knowledge, this is the first paper on the biosorption Cu by L. pulmonaria. 相似文献
949.
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
950.
Souzana Achilleos John S. Evans Panayiotis K. Yiallouros Savvas Kleanthous Joel Schwartz Petros Koutrakis 《Journal of the Air & Waste Management Association (1995)》2014,64(12):1352-1360
Air quality in Cyprus is influenced by both local and transported pollution, including desert dust storms. We examined PM10 concentration data collected in Nicosia (urban representative) from April 1, 1993, through December 11, 2008, and in Ayia Marina (rural background representative) from January 1, 1999, through December 31, 2008. Measurements were conducted using a Tapered Element Oscillating Micro-balance (TEOM). PM10 concentrations, meteorological records, and satellite data were used to identify dust storm days. We investigated long-term trends using a Generalized Additive Model (GAM) after controlling for day of week, month, temperature, wind speed, and relative humidity. In Nicosia, annual PM10 concentrations ranged from 50.4 to 63.8 μg/m3 and exceeded the EU annual standard limit enacted in 2005 of 40 μg/m3 every year. A large, statistically significant impact of urban sources (defined as the difference between urban and background levels) was seen in Nicosia over the period 2000–2008, and was highest during traffic hours, weekdays, cold months, and low wind conditions. Our estimate of the mean (standard error) contribution of urban sources to the daily ambient PM10 was 24.0 (0.4) μg/m3. The study of yearly trends showed that PM10 levels in Nicosia decreased from 59.4 μg/m3 in 1993 to 49.0 μg/m3 in 2008, probably in part as a result of traffic emission control policies in Cyprus. In Ayia Marina, annual concentrations ranged from 27.3 to 35.6 μg/m3, and no obvious time trends were observed. The levels measured at the Cyprus background site are comparable to background concentrations reported in other Eastern Mediterranean countries. Average daily PM10 concentrations during desert dust storms were around 100 μg/m3 since 2000 and much higher in earlier years. Despite the large impact of dust storms and their increasing frequency over time, dust storms were responsible for a small fraction of the exceedances of the daily PM10 limit.
ImplicationsThis paper examines PM10 concentrations in Nicosia, Cyprus, from 1993 to 2008. The decrease in PM10 levels in Nicosia suggests that the implementation of traffic emission control policies in Cyprus has been effective. However, particle levels still exceeded the European Union annual standard, and dust storms were responsible for a small fraction of the daily PM10 limit exceedances. Other natural particles that are not assessed in this study, such as resuspended soil and sea salt, may be responsible in part for the high particle levels. 相似文献