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901.
Microcosm experiments to control anaerobic redox conditions when studying the fate of organic micropollutants in aquifer material 总被引:1,自引:0,他引:1
902.
Plant communities in relation to flooding and soil contamination in a lowland Rhine River floodplain
Schipper AM Lotterman K Leuven RS Ragas AM de Kroon H Hendriks AJ 《Environmental pollution (Barking, Essex : 1987)》2011,159(1):182-189
Using canonical correspondence analysis (CCA), relationships were investigated between plant species composition and flooding characteristics, heavy metal contamination and soil properties in a lowland floodplain of the Rhine River. Floodplain elevation and yearly average flooding duration turned out to be more important for explaining variation in plant species composition than soil heavy metal contamination. Nevertheless, plant species richness and diversity showed a significant decrease with the level of contamination. As single heavy metal concentrations seemed mostly too low for causing phytotoxic effects in plants, this trend is possibly explained by additive effects of multiple contaminants or by the concomitant influences of contamination and non-chemical stressors like flooding. These results suggest that impacts of soil contamination on plants in floodplains could be larger than expected from mere soil concentrations. In general, these findings emphasize the relevance of analyzing effects of toxic substances in concert with the effects of other relevant stressors. 相似文献
903.
Kros J Frumau KF Hensen A de Vries W 《Environmental pollution (Barking, Essex : 1987)》2011,159(11):3171-3182
The integrated modelling system INITIATOR was applied to a landscape in the northern part of the Netherlands to assess current nitrogen fluxes to air and water and the impact of various agricultural measures on these fluxes, using spatially explicit input data on animal numbers, land use, agricultural management, meteorology and soil. Average model results on NH3 deposition and N concentrations in surface water appear to be comparable to observations, but the deviation can be large at local scale, despite the use of high resolution data. Evaluated measures include: air scrubbers reducing NH3 emissions from poultry and pig housing systems, low protein feeding, reduced fertilizer amounts and low-emission stables for cattle. Low protein feeding and restrictive fertilizer application had the largest effect on both N inputs and N losses, resulting in N deposition reductions on Natura 2000 sites of 10% and 12%, respectively. 相似文献
904.
Farm, land, and soil nitrogen budgets for agriculture in Europe calculated with CAPRI 总被引:3,自引:0,他引:3
Leip A Britz W Weiss F de Vries W 《Environmental pollution (Barking, Essex : 1987)》2011,159(11):3243-3253
We calculated farm, land, and soil N-budgets for countries in Europe and the EU27 as a whole using the agro-economic model CAPRI. For EU27, N-surplus is 55 kg N ha−1 yr−1 in a soil budget and 65 kg N2O–N ha−1 yr−1 and 67 kg N ha−1 yr−1 in land and farm budgets, respectively. NUE is 31% for the farm budget, 60% for the land budget and 63% for the soil budget. NS values are mainly related to the excretion (farm budget) and application (soil and land budget) of manure per hectare of total agricultural land. On the other hand, NUE is best explained by the specialization of the agricultural system toward animal production (farm NUE) or the share of imported feedstuff (soil NUE). Total N input, intensive farming, and the specialization to animal production are found to be the main drivers for a high NS and low NUE. 相似文献
905.
We modelled the combined effects of past and expected future changes in climate and nitrogen deposition on tree carbon sequestration by European forests for the period 1900-2050. Two scenarios for deposition (current legislation and maximum technically feasible reductions) and two climate scenarios (no change and SRES A1 scenario) were used. Furthermore, the possible limitation of forest growth by calcium, magnesium, potassium and phosphorus is investigated. The area and age structure of the forests was assumed to stay constant to observations during the period 1970-1990. Under these assumptions, the simulations show that the change in forest growth and carbon sequestration in the past is dominated by changes in nitrogen deposition, while climate change is the major driver for future carbon sequestration. However, its impact is reduced by nitrogen availability. Furthermore, limitations in base cations, especially magnesium, and in phosphorus may significantly affect predicted growth in the future. 相似文献
906.
Faulkner WB Downey D Giles DK Capareda SC 《Journal of the Air & Waste Management Association (1995)》2011,61(4):409-417
Almond harvest accounts for substantial PM10 (particulate matter [PM] < or =10 microm in nominal aerodynamic diameter) emissions in California each harvest season. This paper evaluates the effects of using reduced-pass sweepers and lower harvester separation fan speeds (930 rpm) on lowering PM emissions from almond harvesting operations. In-canopy measurements of PM concentrations were collected along with PM concentration measurements at the orchard boundary; these were used in conjunction with on-site meteorological data and inverse dispersion modeling to back-calculate emission rates from the measured concentrations. The harvester discharge plume was measured as a function of visible plume opacity during conditioning operations. Reduced-pass sweeping showed the potential for reducing PM emissions, but results were confounded because of differences in orchard maturity and irrigation methods. Fuel consumption and sweeping time per unit area were reduced when comparing a reduced-pass sweeper to a conventional sweeper. Reducing the separation fan speed from 1080 to 930 rpm led to reductions in PM emissions. In general, foreign matter levels within harvested product were nominally affected by separation fan speed in the south (less mature) orchard; however, in samples conditioned using the lower fan speed from the north (more mature) orchard, these levels were unacceptable. 相似文献
907.
Mehmet Berkun Egemen Aras Tugce Anılan 《Journal of Material Cycles and Waste Management》2011,13(4):305-313
As an economically developing country, Turkey has very well operated integrated solid waste management applications structured
on modern facilities, besides over 2,000 scattered open dump areas in the country. Integrated waste management applications
seem eligible for the metropolitan cities like Istanbul and Izmit (Kocaeli). Attempts have not been encouraging for the scattered
regional settlements using central storage sites due to financial shortages and received rejections from nearby settlements.
Small-scale compact solid waste management systems with materials recycling and composting can be more suitable alternatives
in the small-scale regional settlements. The major constituents of municipal solid waste are organic in nature and approximately
a quarter of municipal solid waste is recyclable. Although paper, including cardboard, is the main constituent, the composition
of recyclable waste varies strongly by the source or the type of collection point. Solid wastes need primary treatment in
order to be suitable for incineration and composting. Turkey needs to give more emphasis on the usage of modern solid waste
removal technologies to overcome the overgrowing solid waste disposal problems. 相似文献
908.
The circular economy has been developing rapidly in recent years in China. A legislative system has been created to provide
legal protection for the development of a circular economy, including a series of price and tax measures in the waste management
area. These measures form the basic foundation for promoting better waste management under the circular economic model. Many
challenges, however, remain. For instance, the legal system needs to incorporate more sophisticated science, and China lacks
key waste treatment technology that could support the further development of a circular economy. There is also a need to educate
the public about the concept of the circular economy and its benefits. Specific suggestions are made for the development and
implementation of the circular economic model. 相似文献
909.
Hisanori Watanabe Hidekichi Yoshino 《Journal of Material Cycles and Waste Management》2011,13(2):113-117
Since hydrogen is a renewable energy source, biohydrogen has been researched in recent years. However, data on hydrogen fermentation
by a leachate from a waste landfill as inoculum are scarce. We investigated hydrogen production using a leachate from an industrial
waste landfill in Kanagawa Prefecture. The results showed no methane gas production, and the leachate was a suitable inoculum
for hydrogen fermentation. The maximum H2 yield was 2.67 mol of H2 per mol of carbohydrate added, obtained at 30°C and an initial pH of 7. The acetate and butyrate production was significant
when the H2 yield was higher. Oxidation–reduction potential analysis of the culture suggested that hydrogen-producing bacteria in the
leachate were facultative anaerobic. Scanning electron microscope observations revealed that the hydrogen-producing bacteria
comprised bacilli about 2 μm in length. 相似文献
910.
Shinsuke Iijima Morito Nakamura Akira Yokoi Mitsuhiro Kubota Liwei Huang Hitoki Matsuda 《Journal of Material Cycles and Waste Management》2011,13(3):206-212
For an effective decomposition and removal of organic halogenated compounds, a packed-bed non-thermal plasma reactor with
in situ absorption of the resulting halogenated products by alkaline sorbent incorporated was proposed. In the plasma reactor,
α-Al2O3 particles of 1 and 3 mm (mean particle diameter) were packed as solid dielectric medium to enhance the plasma power density
in the reactor. Further, alkaline sorbent of Ca(OH)2 was doped onto the surface of α-Al2O3 particles, in order to remove halogenated products by in situ absorption with Ca(OH)2. A high-voltage and high-frequency pulsed power of −15 to 15 kV and 1 kHz was applied to the wire electrode of the plasma
reactor by means of a DC power source. In the present study, as the sample of an organic halogenated compound that is most
popularly used, we selected dichloromethane (CH2Cl2), and 500 ppm of the initial concentration of CH2Cl2 was fed into the reactor accompanied by air at a fixed flow rate of 500 × 10−6 m3 min−1 at room temperature. As a result, it was recognized that the amount of CH2Cl2 decomposed by non-thermal plasma in an α-Al2O3 particle bed increased with an increase in plasma input power. The ratio of decomposition of CH2Cl2 was almost 100% at 13 kV of electric power and 1 kHz frequency, and CO2, CH3Cl, COCl2, HCl, and Cl2 were observed as the major reaction products. On the other hand, when CH2Cl2 was introduced into the plasma reactor where α-Al2O3 particles doped with Ca(OH)2 were packed, the ratio of decomposition of CH2Cl2 became higher, compared to the case that α-Al2O3 particles were not doped with Ca(OH)2. Moreover, there were no halogenated by-product gases detected in the outlet gas from the reactor. As the solid reaction
products, CaClOH and Ca(ClO)2·4H2O were detected on Ca(OH)2 by X-ray diffraction. From these findings, it was recognized that CH2Cl2 was decomposed more effectively without producing unwanted harmful halogenated by-products in the proposed non-thermal plasma
reactor where α-Al2O3 particles doped with Ca(OH)2 sorbent were packed. 相似文献