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111.
Municipal solid waste incinerator (MSWI) bottom ash may be used as a road construction material; it potentially contains however a sizable quantity of heavy metals, which under the effect of rainfall infiltration through the road structure can be leached out from the material and infiltrate into the underlying soil. An eco-compatibility assessment of MSWI bottom ash reuse in road construction applications necessitates examining the solubility and retention of heavy metals in road soils. This study is dedicated to Pb transfer, sorption and desorption (NEN 7341 standard test) within various soils. These experiments yield results relative to the interaction between road soils and an MSWI bottom ash leachate representative of a "fresh" product, with a high leaching potential. For the soils investigated, the sorption of lead varies between 90% and 99%. For an extraction at pH 7, Pb release is very low (<2%) for all soils, while at pH 4 leaching varies between 4% and 47%. This work shows that Pb may be fixed by some types of road soil in mostly stable forms. 相似文献
112.
Degradation, bioaccumulation and volatile loss of the 14C-labeled phenylurea herbicide isoproturon (IPU) was examined in a freshwater microcosm with the free floating macrophyte species Lemna minor during a 21-day exposure time. Isoproturon volatilisation was very low with 0.13+/-0.01% of the initially applied herbicide. Only a minor amount of the herbicide was completely metabolised, presumably by rhizosphere microorganisms and released as 14CO2. In total, about 9% isoproturon was removed from the aquatic medium during 21 days. The major portion of the pesticide was removed by bioaccumulation of Lemna minor (5.0+/-0.8%) and the bioconcentration factor (BCF) based on freshweight was 15.8+/-0.2. However, this study indicated a high persistence of IPU in freshwater ecosystems and a potential hazard due to bioaccumulation in non-target species. The novel experimental system of this study, developed for easy use and multiple sampling abilities, enabled quantitatively studying the fate of isoproturon and showed high reproducibility with a mean average (14)C-recovery rate of 97.1+/-0.7%. 相似文献
113.
The potential health risks due to inorganic substances, mainly metals, was evaluated for the two resident marine mammals in Hong Kong, the Indo-Pacific Humpback Dolphin (Sousa chinensis) and the Finless Porpoise (Neophocaena phocaenoides). The stomachs from the carcasses of twelve stranded dolphins and fifteen stranded porpoises were collected and the contents examined. Concentrations of thirteen trace elements (Ag, As, Cd, Co, Cr, Cs, Cu, Hg, Mn, Ni, Se, V and Zn) were determined by inductively coupled plasma mass spectrometer (ICP-MS). An assessment of risks of adverse effects was undertaken using two toxicity guideline values, namely the Reference Dose (RfD), commonly used in human health risk assessment, and the Toxicity Reference Value (TRV), based on terrestrial mammal data. The levels of trace metals in stomach contents of dolphins and porpoises were found to be similar. Risk quotients (RQ) calculated for the trace elements showed that risks to the dolphins and porpoises were generally low and within safe limits using the values based on the TRV, which are less conservative than those based on the RfD values. Using the RfD-based values the risks associated with arsenic, cadmium, chromium, copper, nickel and mercury were comparatively higher. The highest RQ was associated with arsenic, however, most of the arsenic in marine organisms should be in the non-toxic organic form, and thus the calculated risk is likely to be overestimated. 相似文献
114.
T. Lubjuhn Wolfgang Winkel Jörg Thomas Epplen Jörg Brün 《Behavioral ecology and sociobiology》2000,48(1):12-17
One of the most interesting aspects of the mating system of pied flycatchers is the regular occurrence of polygyny. Here we
present data on the reproductive success of polygynously paired pied flycatcher males compared to monogamous males based on
paternity analyses through DNA fingerprinting. Males paired with two females suffered a higher loss in reproductive output
per female compared to monogamous males due to (1) a greater proportion of unhatched eggs in their broods, (2) greater nestling
mortality and (3) a greater probability of being cuckolded. Nevertheless, the number of fledglings was significantly greater
for polygynous males. Based on the number of nestlings that returned for subsequent breeding seasons, however, the reproductive
success of monogamous and polygynous males did not differ significantly. These data raise the question as to why males attempt
polygyny.
Received: 16 August 1999 / Received in revised form: 15 March 2000 / Accepted: 18 March 2000 相似文献
115.
Thomas Eisner Maria Eisner Daniel J. Aneshansley Chia-Li Wu Jerrold Meinwald 《Chemoecology》2000,10(4):211-216
Summary. The mint plant, Teucrium marum (family Labiatae), sometimes called cat thyme, contains two methylcyclopentanoid monoterpenes, dolichodial and teucrein. The former compound is potently anti-insectan. It is repellent to ants (Monomorium pharaonis) and induces preening reflexes in flies (Phormia regina) and cockroaches (Periplaneta americana). Evidence is presented suggesting that dolichodial, which is presumed to be the plant's chief defensive agent, is stored in the tiny epidermal capsules that beset the leaves. It is only when the leaves are injured (and the capsules ruptured) that the leaves become repellent. Teucrein, in contrast, has no anti-insectan potency. It is present predominantly in the leaf buds, unlike dolichodial, which is present mostly in mature leaves. It is argued that teucrein is the storage compound from which dolichodial is generated during leaf development. 相似文献
116.
117.
Eva Haslauer Markus Biberacher Thomas Blaschke 《Journal of Environmental Planning and Management》2016,59(5):866-890
General backcasting as a decision support and planning method starts from desired future states and simulates developments backwards until reaching the present state. Development pathways that reveal steps to be taken to reach a certain future state, and milestones that serve as interim goals, are created during the process. Backcasting has hitherto only been applied in workshops or as a theoretical framework and no spatially explicit backcasting model has previously been established. This paper presents the development of a spatially explicit backcasting model. The proposed model first creates a future scenario utilizing an agent-based model and then simulates backwards. It is implemented using the programming language Python. The model has been applied to a case study for sustainable land-use planning in Salzburg, Austria. The results of the model run show a successful backcasting of land-use classes from a future state back to the present, in 10 year time steps. 相似文献
118.
Thomas Hartmann 《Journal of Environmental Planning and Management》2016,59(2):360-377
In response to the extreme flood events of recent decades, the European Union has released the Floods Directive (2007/60/EC), which requires the creation of flood risk management plans. These plans do not yet exist in practice, as water management agencies have until 2015 to put them into action. This contribution will discuss two questions regarding the European flood risk management plan: First, how is the new instrument integrated into the various member states, particularly with respect to the scenario approach? Second, how prepared are the institutions for the collaborative planning paradigm of the flood risk management plan, particularly with respect to the river basin districts approach? Citing examples from France, Germany, the Netherlands, and Great Britain, this paper offers both a pessimistic and an optimistic perspective on the implementation of the new flood risk management instrument. 相似文献
119.
Thomas Zobel 《Journal of Environmental Planning and Management》2016,59(4):587-606
The debate concerning the environmental effectiveness of environmental management systems (EMS) based on ISO 14001 is still open and scholars have called for further studies that can explain the contrasting evidence in previous research. As a response, this study aims to contribute knowledge about the effects of ISO 14001-based EMS by presenting fact-based environmental data. The study focuses on changes in performance over a period of 12 years and includes both firms with an EMS (66 firms) and firms without one (50 firms). Consideration is given to the improvement efforts in the firms before EMS adoption making it possible to neutralize any selection effects where better environmental performance precedes ISO 14001 adoption. Analysis has been carried out using statistical methods for six different environmental areas. No statistically significant differences between certified and non-certified firms concerning the change in the rate of improvement could be found in any of the six areas. However, it can be suspected that EMS adoption has positive effects on energy use and waste production whereas the non-adopting firms seem to perform better concerning air emissions. These mixed results mirrors previous research, which is rather worrying considering the worldwide popularity of EMS based on ISO 14001 in industry. 相似文献
120.