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801.
802.
A. D. Pokarzhevskii N. M. Van Straalen Zh. V. Filimonova A. S. Zaitsev R. O. Butovskii 《Russian Journal of Ecology》2000,31(3):190-197
Studies on the ecotoxicology of soil organisms have led to the revision of views on the trophic structure of ecosystems. It
was found that the microbial link is obligatory and controls the migration of toxicants and their effects in the food chain.
Differences in effects are accounted for by both the physiological stability of organisms and their affliation with relatively
independent and biogeochemically closed ecosystems differing in their spatiotemporal scales. The latter form a hierarchical
three-level structure: ecosystems of unicellular organisms—ecosystems of small multicellular organisms—the ecosystem of large
multicellular organisms, or of biogeocenosis. Trophic networks within the structure are united by ecosystemophagy as the type
of feeding of large multicellular organisms, and this accounts for the importance of the latter as indicators of long-term
changes in a biogeocenosis. 相似文献
803.
Tadesse Getahun Mulat Gebrehiwot Argaw Ambelu Tom Van Gerven Bart Van der Bruggen 《Environmental monitoring and assessment》2014,186(7):4637-4646
The objective of this study was to estimate the potential of organic municipal solid waste generated in an urban setting in a tropical climate to produce biogas. Five different categories of wastes were considered: fruit waste, food waste, yard waste, paper waste, and mixed waste. These fractions were assessed for their efficiency for biogas production in a laboratory-scale batch digester for a total period of 8 weeks at a temperature of 15–30 °C. During this period, fruit waste, food waste, yard waste, paper waste, and mixed waste were observed to produce 0.15, 0.17, 0.10, 0.08, and 0.15 m3 of biogas per kilogram of volatile solids, respectively. The biogas produced and caloric value of each feedstock was in the range of 1.25?×?10?3 m3 (17 kWh)/cap/day (paper waste) to 15?×?10?3 m3 (170 kWh)/cap/day (mixed waste). Paper waste produced the least (<1×10?3(<17.8 kWh)/cap/day), and mixed waste produced the highest methane yield (10?×?10?3 m3 (178 kWh)/cap/day). Thus, mixed waste was found to be more efficient than other feedstocks for biogas and methane production; this was mainly related to the better C/N ratio in mixed waste. Taking the total waste production in Jimma into account, the total mixed organic solid waste could produce 865?×?103 m3 (5.4 m3/capita) of biogas or 537?×?103 m3 (3.4 m3/capita) of methane per year. The total caloric value of methane production potential from mixed organic municipal solid waste was many times higher than the total energy requirement of the area. 相似文献
804.
Nguyen Van Hop Hoang Thi Quynh Dieu Nguyen Hai Phong 《Environmental monitoring and assessment》2017,189(6):299
The concentrations of seven toxic metals (cadmium (Cd), nickel (Ni), chromium (Cr), arsenic (As), lead (Pb), copper (Cu), and zinc (Zn)) were determined in sediments and the soft tissues of a bivalve species (Meretrix lyrata) collected from the Tien Estuary in Tien Giang Province, South Vietnam. The total metal concentrations in sediments (mg/kg dry weight) increased as Cd (0.06) < Cu (5.0) < Pb (13.9) < As (16.3) < Ni (24) < Cr (50) < Zn (62). Speciation analysis revealed that these metals existed mainly in the residual fraction (43–94%), followed by the Fe-Mn oxide-bound (5–35%) and organic/sulfide-bound (0.6–9.2%) fractions. The metal concentrations in M. lyrata (mg/kg dry weight) were in the ranges of 1.3–1.9 (Cd), 1.5–2.8 (Ni), 1.8–3.4 (Cr), 11–16 (As), 0.3–0.6 (Pb), 6.9–8.7 (Cu), and 95–128 (Zn), which are safe for human consumption. The order of the mean biota-sediment accumulation factor (BSAF) of the metals in the non-residual fractions of the sediment for M. lyrata was Cd > Cu > As > Zn > Cr > Ni > Pb. The Risk Assessment Codes (RACs) suggest that the highest mobility of Cd (with RAC = 37%) poses greater environmental risk to aquatic biota. Correlation analysis results show that M. lyrata can be used as a biomonitor of Cd and Cu pollution in the exchangeable, acid-soluble, and non-residual sediment fractions. 相似文献
805.
Geological CO2 capture and storage (CCS) is among the main near-term contenders for addressing the problem of global climate change. Even
in a baseline scenario, with no comprehensive international climate policy, a moderate level of CCS technology is expected
to be deployed, given the economic benefits associated with enhanced oil and gas recovery. With stringent climate change control,
CCS technologies will probably be installed on an industrial scale. Geologically stored CO2, however, may leak back to the atmosphere, which could render CCS ineffective as climate change reduction option. This article
presents a long-term energy scenario study for Europe, in which we assess the significance for climate policy making of leakage
of CO2 artificially stored in underground geological formations. A detailed sensitivity analysis is performed for the CO2 leakage rate with the bottom-up energy systems model MARKAL, enriched for this purpose with a large set of CO2 capture technologies (in the power sector, industry, and for the production of hydrogen) and storage options (among which
enhanced oil and gas recovery, enhanced coal bed methane recovery, depleted fossil fuel fields, and aquifers). Through a series
of model runs, we confirm that a leakage rate of 0.1%/year seems acceptable for CCS to constitute a meaningful climate change
mitigation option, whereas one of 1%/year is not. CCS is essentially no option to achieve CO2 emission reductions when the leakage rate is as high as 1%/year, so more reductions need to be achieved through the use of
renewables or nuclear power, or in sectors like industry and transport. We calculate that under strict climate control policy,
the cumulative captured and geologically stored CO2 by 2100 in the electricity sector, when the leakage rate is 0.1%/year, amounts to about 45,000 MtCO2. Only a little over 10,000 MtCO2 cumulative power-generation-related emissions are captured and stored underground by the end of the century when the leakage
rate is 1%/year. Overall marginal CO2 abatement costs increase from a few €/tCO2 today to well over 150 €/tCO2 in 2100, under an atmospheric CO2 concentration constraint of 550 ppmv. Carbon costs in 2100 turn out to be about 40 €/tCO2 higher when the annual leakage rate is 1%/year in comparison to when there is no CO2 leakage. Irrespective of whether CCS deployment is affected by gradual CO2 seepage, the annual welfare loss in Europe induced by the implementation of policies preventing “dangerous anthropogenic
interference with the climate system” (under our assumption, implying a climate stabilisation target of 550 ppmv CO2 concentration) remains below 0.5% of GDP during the entire century.
相似文献
Koen SmekensEmail: |
806.
M. M. Lyons P. Aas J. D. Pakulski L. Van Waasbergen R. V. Miller D. L. Mitchell W. H. Jeffrey 《Marine Biology》1998,130(3):537-543
Ultraviolet radiation (UVR) has been implicated in coral-bleaching processes and UVR may create stress to marine organisms
by damage to DNA. Absorption of energy from UVB (280 to 320 nm) induces direct damage to DNA via cyclobutane pyrimidine dimer
photoproduct-formation. We examined the extent of DNA damage created by UVR in coral reef microbial communities and whether
the coral-surface microlayer (CSM) provides protection from UVR to the microorganisms found there. Diel patterns and depth
profiles of UVR effects were examined in coral mucus (coral-surface microlayer, CSM) from Montastraea faveolata and Colpophyllia natans, and water-column samples of similar depths. UV-induced photodamage was determined using a radioimmunoassay specific for
cyclobutane pyrimidine dimers (thymine dimers). Significant photodamage was detected in water-column and CSM samples, although
the level of damage in CSM samples was consistently lower than in water-column samples collected from the same depth, suggesting
the presence of photoprotective mechanisms within the CSM. Diel patterns of photodamage were detected in both water-column
and CSM samples, but peak damage occurred earlier in the day for the CSM samples, suggesting differences in damage and repair
kinetics between the water column and CSM. The results suggest that microorganisms within the CSM are afforded some protection
from UVR stress and that changes in the amount of DNA damage in these organisms may be an indicator of changing UVR stress
to corals.
Received: 10 January 1997 / Accepted: 15 September 1997 相似文献
807.
Patterson PH Adrizal A Hulet RM Bates RM Myers CA Martin GP Shockey RL van der Grinten M 《Journal of environmental science and health. Part. B》2008,43(2):199-204
This study sought to evaluate the potential of trees planted around commercial poultry farms to trap ammonia (NH(3)), the gas of greatest environmental concern to the poultry industry. Four plant species (Norway spruce, Spike hybrid poplar, Streamco willow, and hybrid willow) were planted on eight commercial farms from 2003 to 2004. Because temperature (T) can be a stressor for trees, T was monitored in 2005 with data loggers among the trees in front of the exhaust fans (11.4 to 17.7 m) and at a control distance away from the fans (48 m) during all four seasons in Pennsylvania. Norway spruce (Picea abies) foliage samples were taken in August 2005 from one turkey and two layer farms for dry matter (DM) and nitrogen (N) analysis. The two layer farms had both Norway spruce and Spike hybrid poplar (Populus deltoides x Populus nigra) plantings sampled as well allowing comparisons of species and the effect of plant location near the fans versus a control distance away. Proximity to the fans had a clear effect on spruce foliar N with greater concentrations downwind of the fans than at control distances (3.03 vs. 1.88%; P < or = 0.0005). Plant location was again a significant factor for foliar N of both poplar and spruce on the two farms with both species showing greater N adjacent to the fans compared to the controls (3.75 vs. 2.32%; P < or = 0.0001). Pooled foliar DM of both plants was also greater among those near the fans (56.17, fan vs. 44.67%, control; P < or = 0.005). Species differences were also significant showing the potential of poplar to retain greater foliar N than spruce (3.52 vs. 2.55%; P < or = 0.001) with less DM (46.00 vs. 54.83%; P < or = 0.05) in a vegetative buffer setting. The results indicated plants were not stressed by the T near exhaust fans with mean seasonal T (13.04 vs. 13.03 degrees C, respectively) not significantly different from controls. This suggested poultry house exhaust air among the trees near the fans would not result in dormancy stressors on the plants compared to controls away from the fans. 相似文献
808.
Zusammenfassung
Hintergrund und Ziel Die Exposition gentechnisch ver?nderter Kulturpflanzen erfordert die Beobachtung ihrer Umweltwirkungen. Ziel der Beitragsserie
über die Beobachtung ?kologischer Wirkungen von GVO ist es, den hierzu erreichten Stand der Wissenschaft vorzustellen. Da
bei einem Bundesl?nder und ggf. europ?ische Staaten übergreifenden Monitoring besonders auf methodisch vergleichbare und r?umlich
aussagekr?ftige Daten zu achten ist, werden in diesem einführenden Beitrag wissenschaftstheoretische und statistische Grundlagen
des Monitoring sowie die Standardisierung der Beobachtungsverfahren behandelt.
Schwerpunkte Im Mittelpunkt stehen zun?chst ?kologische Anforderungen an das GVO-Monitoring. Um mit GVO ggf. zusammenh?ngende Umweltver?nderungen
ermitteln zu k?nnen, ist eine Eingliederung in bestehende Umweltbeobachtungsprogramme erforderlich. GVO-Exposition und-Wirkung
sind aufeinander bezogen über die Organisationsstufen ?kologischer Systeme hinweg zu erfassen. Ein effizientes und suffizientes
Monitoring bedarf eines wissenschaftstheoretisch und statistisch soliden Designs. Deshalb werden einem weiteren Schwerpunkt
dieses Beitrags wissenschaftstheoretische Grundlagen der Hypothesenbildung und-prüfung behandelt. Hierfür bedarf es Daten,
die mehreren, im Einzelnen behandelten Qualit?tskriterien entsprechen müssen. Eines dieser Kriterien ist die r?umliche und
zeitliche Verallgemeinerungsf?higkeit der Monitoring-Befunde, die in dem dritten Schwerpunkt des Beitrags dargestellt wird.
Schlussfolgerungen Für die Prüfung von Hypothesen über Umweltfolgen von GVO sind konsequent ?kosystemforschung und Monitoring eng miteinander
zu vernetzen. Denn sie erfüllen komplement?re Funktionen, die für das Monitoring der Umweltwirkungen von GVO von gro?er praktischer
und wissenschaftlicher Bedeutung sind.
Empfehlungen Das GVO-Monitoring sollte in bestehende Programme der ?kosystemforschung und der Umweltbeobachtung eingebettet werden und
die ?kologischen Organisationsstufen sowie GVO-Exposition und-Wirkung einschlie?en. Die Lokalisierung der Messorte sollte
die erwartete Exposition oder Wirkung berücksichtigen.
Perspektiven Weitere Beitr?ge dieser Serie werden die Messplanung, das Pollenmonitoring und die r?umliche Verallgemeinerung von Ergebnissen
standortspezifischer Messungen oder Modellierungen behandeln.
Environmental monitoring of ecological impacts of GMOs
Goal, Scope and Background The release of genetically modified organisms (GMOs) may result in ecological impacts to be monitored. This series presents the state-of-art concerning the environmental monitoring of ecological impacts of GMOs. Since this monitoring is conducted by several authorities, the methodical comparability and spatial validity of the monitoring data is crucial. Thus, the respective fundamentals of philosophy of science and of statistics as well as the methodical standardisation form the focus of this article. Main Features At first, the monitoring requirements will be described from the viewpoint of ecology. Consequently, the GMO monitoring needs to be integrated into existing programmes. Exposure and effects of GMOs have to be monitored across the hierarchy of ecological organisation. For monitoring to be efficient and sufficient, the design must be founded in terms of philosophy of science and statistics. Hence the fundamentals concerning the verification of hypotheses represent another feature of this article. The data used for the verification of hypotheses must comply with quality criteria. One of these criteria is the spatial and temporal extrapolation of the monitoring results, which is the third feature in this introductory article. Conclusions The evaluation of hypotheses on GMO impacts requires the linkage to ecosystems research and environmental monitoring. These both are, in terms of methodology, complementary and of significant technical and scientific value for GMO monitoring. Recommendations GMO-monitoring should closely be connected with ecosystems research and environmental monitoring. The levels of ecological organisation should be covered as well as the exposure and the effects of GMOs. The expected GMO exposure and effects should be considered by localising the monitoring sites. Perspectives Further articles of this series will deal with network designing, GMO pollen monitoring and extrapolation of site-specific measurements and modelling results.相似文献
809.
A.H.W. Beusen A.F. Bouwman P.S.C. Heuberger G. Van Drecht K.W. Van Der Hoek 《Atmospheric environment (Oxford, England : 1994)》2008,42(24):6067-6077
Here we present an uncertainty analysis of NH3 emissions from agricultural production systems based on a global NH3 emission inventory with a 5×5 min resolution. Of all results the mean is given with a range (10% and 90% percentile). The uncertainty range for the global NH3 emission from agricultural systems is 27–38 (with a mean of 32) Tg NH3-N yr−1, N fertilizer use contributing 10–12 (11) Tg yr−1 and livestock production 16–27 (21) Tg yr−1. Most of the emissions from livestock production come from animal houses and storage systems (31–55%); smaller contributions come from the spreading of animal manure (23–38%) and grazing animals (17–37%). This uncertainty analysis allows for identifying and improving those input parameters with a major influence on the results. The most important determinants of the uncertainty related to the global agricultural NH3 emission comprise four parameters (N excretion rates, NH3 emission rates for manure in animal houses and storage, the fraction of the time that ruminants graze and the fraction of non-agricultural use of manure) specific to mixed and landless systems, and total animal stocks. Nitrogen excretion rates and NH3 emission rates from animal houses and storage systems are shown consistently to be the most important parameters in most parts of the world. Input parameters for pastoral systems are less relevant. However, there are clear differences between world regions and individual countries, reflecting the differences in livestock production systems. 相似文献
810.
Sampling method, storage and pretreatment of sediment affect AVS concentrations with consequences for bioassay responses 总被引:1,自引:0,他引:1
De Lange HJ Van Griethuysen C Koelmans AA 《Environmental pollution (Barking, Essex : 1987)》2008,151(1):243-251
Sediment treatment and sediment storage may alter sediment toxicity, and consequently biotic response. Purpose of our study was to combine these three aspects (treatment-toxicity-biotic response) in one integrated approach. We used Acid Volatile Sulfide (AVS) concentrations as a proxy of the disturbance of the sediment. AVS and Simultaneously Extracted Metal (SEM) concentrations were compared to bioassay responses with the freshwater benthic macroinvertebrate Asellus aquaticus. Storage conditions and sediment treatment affected AVS but not SEM levels. AVS can be used as a proxy for sediment disturbance. The best way to pretreat the sediment for use in a bioassay in order to maintain initial AVS conditions was to sample the sediment with an Ekman grab, immediately store it in a jar without headspace, and freeze it as soon as possible. In a survey using seven different sediments, bioassay responses of A. aquaticus were correlated with SEM and AVS characteristics. 相似文献